Taken in Saltsjöbaden, Stockholm, Sweden using Nikon D70s and Nikkor AF 50/1.8D. Post processed in Adobe Lightroom.

One of the greatest things with a SLR type camera is that it is possible to control the focus in the picture. This area is known as the DOF or the Depth-of-Field, or the Depth of Focus. This the space in a picture where things are in focus. In front of the DOF is the near out of focus field and beyond is the far out of focus field. There are certain things that controls this field and this article will describe them and how you can use them to improve your pictures. Without going into the actual optics, I will try to explain how to achieve the desired DOF and what it can be used for.

What affects DOF?

The DOF is actually the part of an image that is in focus. Any lens have a certain volume where things are percieved to be in focus and this volume or field of focus is referred to as the DOF. There are several factors that influences this, one of the most important factors is the aperture setting of the camera.

The aperture

The aperture controls how much light that falls into the camera at a given moment, it is a diaphragm in most cameras it is located inside the lens or just behind it, in the SLR type cameras it is located in the detacheable lens that is part of a camera system.

The aperture can generally be set in several steps. Earlier lenses permitted a limited number of steps but modern lenses and digital cameras permits the aperture almost always to be set in steps of 1/3 of a EV. The aperture is expressed as a ratio between the focal length and the diameter of the diaphragm and therefore it is written as f / 5.6 for example.

Cheaper lenses have a more narrow range of apertures than more expensive lenses, this means you can “open up” the aperture more on the expensive end, this is sometimes called “fast” lens (because they give shorter shutter times for the same scene during same conditions as a less expensive lens does) or more “sensitive”.

If you are using a good lens and you are setting it to the  lowest f-stop permitted then you will have the most narrow DOF that this lens can produce. This is a start and a setting you might want to use during low light conditions but remember that your shallow DOF can make it difficult to get the full scene in sharp focus.

The focal length

The focal length plays together with the aperture of course as we have already talked about. The focal length is what you “zoom” to when you zoom, or the fixed focal lenght of your prime lens. The smaller the focal length, the wider the field of view and the deeper the DOF becomes.

The greater the focal length, the more you “zoom in” the shallower the DOF becomes.

The focus point

The focus point is the last part of our equation. The closer to you the focus point lies the shallower the DOF is. The further away you focus the deeper the DOF will become.

It is all about rations between these three, the aperture, the focal length and the distance of the focus point. If you want to create a shallow DOF you should open the aperture, zoom is as much as possible, go close as much as possible and then focus closely.

Remember also that most of your DOF is behind the point of focus, when you focus on somethin the DOF arranges so that you have 1/3 of the range in front of your focal point and 2/3 behind it. Make use of this!

Portraits

This is used in portrait photography to create a sense of depth in the image. Typically you see the model in sharp focus and the background cast in blurriness, this is due to using the DOF properly.

Portrait optics are usually in the range of 90-135 mm focal range and can often be used with an aperture up to f / 2,8 which allows the photographer good control over the DOF and to photograph in the low light of dawn and sunset.

Hyperfocal charts

Finally

These are the things that affects your DOF:

• Focal length
• Aperture setting f / x
• Distance to focus point

When you focus on something the DOF extends 2/3 beyond that point and 1/3 in front of it.

Battery Charge

Table is given for 20°C.
Adjust table with 0.022V/°C when deviating from this temperature.

Unloading-end: 11.8V, charge with 13.2-14.4V. Battery will start gassing at 14.4V (do not exceed). Continuus preservation charge max 13.2V. Float charge; 13.4V for gelled electrolyte, 13.5V for AGM (Absorbed Glass Mat) and 13.8V for flooded cells.

Precision of charge voltage is critical to keep sulfatisation at a minimum. An error of 5% may be enough to reduce life substantially.

A newly charged battery will quickly drop to 13.2V and then slowly settle at 12.6V. After full charge let battery rest 20 hours before measuring open circuit voltage. There might be residual surface charges on the conductor plates otherwise.

Equalization charge – maximum 2 hours at 15V. Make sure ventilation is good and battery temperature is constanly monitored.

On this page are lots of various collected nice to know things as well as a swedish style sheet and two templates, one for technical documentation and one for writing a business-like commercial letter. Tills sist så har min sida åter öppnats om typsättningsspråket LaTeX där det finns en massa tips och tricks för den som fortfarande ägnar sig åt detta. Jag ser fortfarande dagligen folk som länkar till den gamla sidan så genom att ge den nya samma URL hoppas jag att ni hittar tillbaka igen.

På denna sida finns en massa olika saker som jag samlat på mig genom åren och det inkluderar också ett svenst stylesheet för typsättning av svenska dokument, en mall för teknisk dokumentation samt en mall för att skriva brev. ]]> http://www.ichimusai.org/2009/11/02/latex-page-re-opened/feed/ 0 http://www.ichimusai.org/2009/04/05/learning-from-the-masters/ http://www.ichimusai.org/2009/04/05/learning-from-the-masters/#comments Sat, 04 Apr 2009 22:50:24 +0000 Ichimusai http://www.ichimusai.org/?p=2025 A little while ago I found this excellent blog on Nikonians by Martin Turner. He writes about how the classic potratit painters worked and how we can improved our portrait photography by learning from these masters. He has written several very interesting blog posts on this subjects and I felt like commenting on them myself.

In his first post also titled “Learning about portraits from the masters” he discusses the context of the portrait more than the actual technique to pain or photograph. A portrait is supposed to say something about the person being portrayed and therefore it is important to not lose context and pay some attention to the surroundings of the person, the positioning of the subject, any other props or objects in the picture should have meaning and add to the portrait and not detract from the person being potrayed. I think this is an important lesson and something that is easily forgotten.

In his second post he speaks about differential focus something that has been used by painters for a long time and photographers using a telephoto lens, wide open aperture and focusing as close as possible to re-create. Of course post processing can also be used to achive this and there are more than one way of doing nice differential focussing on a subject.

For a portrait we want the eyes to be sharp, then the mouth and the hair are also important — putting too much fuzziness on the hair makes things look strange and the eyes and mouth are what we as humans focus mostly on when we are viewing a portrait of someone else. An excellent example about this is the painting of a Genoese nobleman painted by Bernardo Strozzi in oil on canvas.

Another thing that he notices are also that backgrounds in paintins are almost always very dark. Almost to the point of being black but never completely black there is always some texture to them but in a very subtle way and the idea of isolating the person from the background is very evident.

Today in photography we often use light backgrounds, even white overexposed so called high key shots which usually means you put 4 times as much light on the background as you do on the subject. Makes it easy to cut out in photoshop and re-arrange in a different background but I get a feeling there is a reason that portrait painters never used such backgrounds.

He also talkes a lot about skin details and softening of the skin in portrait. This was done by painters also using selective focussing techniques when painting but this is also likely down to that our minds generally don’t remember much skin details, we focus on the areas around the eyes and mouth and we tent not to remember too much on other details.

The rest of the posts are also interesting but his number 2 post was the best one so far in my opinion.

You can find Martin Turners Nikonian blog here if you want to read more, and I hope you will because it is very interesting to read his articles!

I am a guy who like walking in the woods, hiking, trekking and just generally being outdoor when possible especially in the summer time. I try to make at least a few day trips and if possible an overnight in a tent as well every summer as a minimum, it is something special when you are cooking in the wilderness, sleeping in a tent and generally having to struggle a little more than you normally do every day to and from work. If nothing else you appreciate a nice bed when you come home again

On top of that I am an unchangeable gadget-guy, and I really enjoy knowing the altitude I am on right now, the bearing I am walking in, my position, the time, when the sun rises and sets on the latitude that I am right now and many other things. So my latest addition to things I won’t leave home without now is a Suunto Core wristwatch.

This little gem can do a lot of things and it is a watch specially designed for outdoorsmanship more than anything else. This is not the first “trekker’s watch” I have owned, I also have an “Origo” watch but after a particularly rough outing in the United Arab Emirates a couple of years ago the altimeter broke on that one. So I have decided to get myself a new watch and now I recently bought it.

The Suunto Core watch keeps two times, good for traveling and it has what you expect from a modern digital watch, countdown (99 min max) and works wel as a stopwatch (24 h max). On top of that you can program it with the closest city and it will show the time the sun rises and sets for the date, something that changes drastically right now, the day becomes longer with about 6 minutes every day now and the nights shorter here in Stockholm.

The watch also contains three interesting functions for the hiker not normally found on wrist watches and they are altimeter that shows how high over the sea you are at the moment, barometer showing the air pressure (sea level equivalent) and an electronic compass.

Suunto Core, outdoors sportswatch

The altimeter and barometer are actually two faces of the same coin here. You can select the profile yourself, if you want the watch to be in altimeter mode when you climb, then you can set it to barometric mode when you stop for the night and the watch will tell you the air pressure and assume that you are staying on the same level. You can not get both at the same time though because both the barometer and the altimeter works from the same air pressure sensor. If you climb a mountain the air pressure lowers with every meter you climb, the watch senses this change in air pressure and can therefore know how many meters you have scaled. In barometric mode you fix the altitude and the watch instead registers the changes in air pressure that preceeds an oncoming storm or weather front.

The watch can automatically shift between altimeter and barometer mode, it understands when you start climbing because the air pressure shifts too fast and then it switches to altimeter. If you stay it will after 12 minutes of no change in the altitude (or very small changes) shift back to barometric mode. Brilliant. Over a full days walking around I generally don’t have to recalibrate it for more than 20-40 meters error by the end of the day.

In barometric mode it can also tell you if there is a sudden drop in air pressure. This might signify an oncoming sqall or storm and you can set an audible and visible alarm on the watch to go off if this happens. There is also a 24 hour trend graph that will show you the changes in barometric pressure over the last day and night. There is also an arrow indicator showing you if the air pressure is stable, tends to rise, tends to drop and the attitude for the last 3 and 6 hours. Great for checking if the current weather is stable. I have observed the barometric pressure alarm go off twice. In both accounts it started snowing heavily hours later so I believe it is working pretty well!

The last function of the pressure gauge is the “snorkeling feature” where it can tell you when you snorcle in the hot waters of the Maldives or some other nice place how deep you have been as maximum and how deep you are now. Not quite a diving instrument (watch should not be submerged more than 10 meters really) but it is still a pretty fun feature.

A logging function can be used to keep track of your climbing and descending over time if you want. It will log the altitude and the current time as often as you want and you may also save the log for a later review. You can also set a reference altitude and the watch will show you how much above or below your reference you currenly are.

You can also have it show accumulated inclines declines, something that I thought was pretty neat in a ski slope…

There is also a temperature measurement but since the watch is warmed by your arm it generally does not show air temperature. If you take your watch of and leave it for 30 minutes or so it should give you a pretty good temperature reading though. The temperature is also necessary for the accuracy of the air pressure measurement.

The compass is great, works well but uses battery more than other thngs and because of this the watch will turn it off after one minute of operation; you will then have to press a button to turn it on again for another minute. If you have the backlight lit during compas operation it will flash as it goes dark for each measurement that is done – about 2 per second. The compass can be set to try to stay in a certain direction, it will show with arrows how much in error your current direction is and point you in the right direction and the precision is actually pretty good in the woods. Calibration is simple, turn it on, slowly spin a full circle clockwise and it will recalibrate itself. In urban environment there are sometimes problems where there are heavy electrical machinery and other ferro-magnetic materials at work that will confuse it – try looking at it while a metro train in the underground drives past… but most of the time it can be used there as well.

All in all I really love this watch. I recommend it for everyone who loves to be outdoors, hiking, fishing, hunting, climbing, skiing… this is for you!

I rate it 5/5.

2.6GHz Spectrum Sweden

Duplex distance for FDD bands are 120 MHz. Uplink covers UARFCN 12500-12850 and downlink is 13100-13450 and the TDD band is 12850-13100.

The 50 MHz TDD band in the middle between UL/DL portions of the FDD band is thought to be used for Wimax in the future. Intel Capital Corporation will probably work together with some operator to provide WiMax coverage in this band.

I have gotten a few questions on how to set the camera up for good night shots and there is really nothing to it this is what I normally do is very simple things. If you check your camera manual you should be able to follow the same settings.

Here is an example of a night shot that I have taken with my old Nikon D70s:

Nikon D70s, Taken from the roof top of the old tax building in the south end of stockholm using a tripod and long exposure. 30 second exposure and f/20.

Equipment

The most important tool of night photography is the tripod. If you do not have one, or can not take one to the place you wish to shoot from, then you should seriously consider again if it is not possible. Perhaps you can get someone to help you with it if the problem is carrying it. Perhaps you can get one of these small tripods or perhaps a gorillapod to use instead?

Bangkok, handheld D70s in the night

Another useful item is the bean bag which is basically a fabric bag which has been filled to 2/3rds with rice, small beans or some other such useful type of grain. This bag is great because you can use it anywhere, it forms an cushions your camera nicely and it will help you also with macro photography. You need usually two bean bags, one under your camera house, the other under your lens as support.

The next very useful item is the remote release for the shutter. If you don’t want to invest in a remote shutter release cable or IR remote for your camera you can use the timer on the camera to delay the actual photo taking between 5-20 seconds. This is because you want the camera to take the picture and be completely shake free. If you are using a cable release then make sure it is not tight when you shoot so you are pulling the camera. Using the IR remote is usually never a problem, but does require batteries and they don’t work with all cameras. Almost all cameras have the timer though and putting that on say 10 seconds delay is usually quite enough to make sure the camera is not shaking when the picture is taking.

Camera settings

If you are using a digital SLR camera (dSLR) then you should also consider the mirror lock-up mode that many cameras have now. The mirror when it moves produce vibrations and they can be very difficult to get rid of especially if your shutter time is in the region of 1/30 s down to 2 s. The remote release or timer release does not help here. So if your camera do not have this feature try to avoid this region of shutter times completely to avoid the mirror slap to shake the camera and thereby produce a blurry picture.

City hall in Banja Luka

The ISO setting on the camera should be the setting that produce minimum noise. This is usually the lowest ISO setting on the camera although in some cases the camera sensor can be optimized for a slightly higher ISO as the premium in regard to noise. On the Nikon D300 for example the recommended lowest setting is ISO 200 although the camera can go -1 EV down from this (one full stop) that means ISO 100 the manual actually state the quality of the photos are usually better at ISO 200. Consult your manual. Always turn off the auto iso mode because otherwise the camera will increase the ISO setting automatically when it sees your dark frame when you are trying to take a picture.

Never use high ISO if you can avoid it. The pictures will be noisy and or grainy. However if you don’t have the tripod or just want to experiment you can set the ISO to whatever you want and have a blast. Here is an example of handheld shooting in the middle of the night with very high sensitivity on the camera, ISO 3200 which does produce quite a bit of noise but in this case it was not too bad for the picture since it was quite foggy anyway:

Handheld shot using high ISO 3200 on a D300. Lens was Nikkor AF-S DX VR 16-85/3.5-5.6 G ED-IF

Turn off Active D-Lighting or high dynamic range if your camera has such features. They are designed to “compress” the dynamics in the image by increasing the luminance in the dark parts and decreasing it in the highlights. The decreasing of highlights is not bad for this but the lifting of the shadows does produce a fair amount of extra noise. Make sure these features are turned off before you go shooting in the dark your you may be very disappointed with your camera.

The glass obelisk in the middle of Stockholm City. A bench was used as a support instead of a tripod, but it was not enought so the ISO was raised also. On the D70s you can see that it causes a lot of noise.

Use a sensible aperture, something like f/8 is usually great, it gives you a good depth of field DOF or focus depth to work with and it allows you to take pictures that are sharp from a few meters away all to infinity. So even if you miss the focus slightly your pictures will still be sharp.

Use spot focusing on a single point and pre-focus before you actually take the shot. Use the autofocus if it works, with some cameras it can be difficult to get it working well in darkness, but there is usualluy some contrasts the camera can work with. Then flip the focus to manual so it will not auto-focus at all then then use the time or cable release to take the picture. The reason for this is to avoid that the camera starts “hunting” for focus and misses what you are trying to photograph or get a very bad out of focus picture.

Use sensible focal lengths. Usually you can leave the 600 mm behind, somewhere from 12-300 mm is your useful focal range when working in the darkness. Wide angles can be effective, so can telephoto lenses but they are more difficult due to their extension and heavy weight. You need a very good tripod to use a 300 mm in the night with 15 seconds shutter time.

I also recommend that you take fresh batteries, at least here in Sweden it is getting rather cold at night and batteries that are not fresh may stop working suddenly when the temperature drops. Charge everything during the day before you go on a night shoot.

Set the camera to aperture priority mode (A) and then select an aperture somewhere around f/8 is a good starting point for most night shots. A too wide aperture and you will get a very shallow focus field which means that you have to work hard to get the focus where you want it, the cameras autofocus is often wrong in bad light.

Winter night shot. Using tripod. The weird colours in the sky are reflected sodium lights from the near by highway.

Set the camera to single shot mode. With the exposures you may expect it just don’t make sense to set the camera to continuous shooting mode.

Use raw mode. This helps a lot, whatever mistake you do you have a much better chance of fixing it if you shoot raw and use your cameras software to convert that into whatever format you are happy with using. Lots of post processing software from the free Picasa program to the more expensive Adobe Lightroom can also read and use camera raw files directly from the most well known brands!

If you have various settings on your raw, use raw without compression (or non-destructive compression) and the highest bit rate you can afford.

Summary

Camera settings

• White balance to auto or to daylight neutral. You may experiment with this because neon lights have very different light temperatures.
• Use the mirror lock-up mode when available, especially if you are shooting in the 1/30 – 2 s range.
• ISO 200 – Auto ISO must be turned OFF, or the camera will try to increase the ISO automatically.
• Turn off Active D-Lighting and other such features
• Use only RAW, set it to 14 bits and no compression if you can
• Single shot mode
• Aperture priority (A) mode with f/8 or a similar aperture. Useful apertures range from f/4 to about f/11 in most cases.

Equipment

• Tripod – your important tool, bean bags or similar
• Cable release or IR release

• Continuous shooting (Ch or continuous high)
• Tracking autofocus
• Aperture priority
• ISO200
• Center focus
• Matrix metering
• White balance daylight/cloudy
• RAW format

Here are my arguments for each of these settings.

Continuous shooting this is great because if something happens unexpectedly you just point and keep shooting frame after frame and you might get that special picture even if you was not ready to compose and wait for the moment. Things happens fast in the street so be prepared. A useful lens to have mounted is a superzoom, 18-200 mm or similar, they give you great range and can handle almost any urban situation. The drawback is of course that superzooms are a compromise and may lack sharpness for example.

Tracking autofocus this means the camera keeps focussing all the time even if you keep shooting frame after frame. This is good for tracking moving objects but you have to be aware where the focus points are in your frame. On Nikon cameras this is AF-C (Autofocus continuous). Single time focusing is called AF-S.

Aperture priority or the “A” mode on the camera. This allows you to select the aperture for best depth of field and focus and the camera will automatically pick the apropriate shutter time for a good exposure. This means you don’t have to worry about the exposure and you still maintain a high level of control. Most lenses are sharpest when they are stopped down 2-3 steps. For most this means that f/5.6 – f/11 is probably the best choice in broad daylight. As your light diminish, keep shooting but open the aperture to f/3.5 or f/2.8 or even further if your lens supports it! Most superzooms can not open byond 3.5 at their broad end and 5.6 at their far end.

ISO200 this is a good setting because it minimises the noise from the sensor. If the light conditions are low, raise it but do it with caution since it can produce severely grainy images. Some cameras are much better than others though, you may want to experiment with this. But if your light conditions do not require it—keep your ISO low.

Center focus is preferred because thats where you aim. Use the AF-L (autofocus lock) button to lock if you wish to recompose. The reason center focus is so nice is that if something happens quickly you tract it the focus system has a better chance of concentrating on the object you are tracking. On Nikon cameras the 21 point focus system is great. On the older models as the D70 that has a very limited number of focus points use the single center dot.

Matrix metering means the camera is ready for most light conditions. Activate the “highlight” function on your display to see if the metering has overexposed the picture, then use the exposure compensation setting +/- to change, recompose and take another shot. Using spot metering it may be very difficult to get the right exposure when there are multiple light sources as it generally is in the city. Centre weighted can sometimes be useful but most of the time matric metering is the best.

White balance does not matter too much if you are shooting RAW which you should be anyway… you can always correct this afterwards in your post processing because RAW files keep the sensor data as it was while JPEG will apply the white balance to the final picture. If you are shooting JPEG then set your WB accordinly, if you are shooting RAW you may do so but auto is usually fine as well.

RAW format is great because it allows you to adjust exposure and white balance with the maximum dynamics in the picture. In RAW you can easily correct 1 EV underexposure but if you attempt to do this on a JPEG the picture usually does not fare well.

JPEG format is not listed above but still very useful in certain situations… There is one time I will flip to JPEG when shooting street phot and that is when I will be taking long series of pictures of some event such as marathon runners or similar. The reason is that when I shoot RAW my camera buffer overloads after a few pictures and the camera can not fire as rapidly as in the beginning because it has to wait for the memory card to “swallow” all the data. Since JPEG images are pre-compressed before they are written to the memory card they are smaller and thus allows me to shoot very long series of pictures before the camera memory buffer is full and it starts to “stutter”. Don’t forget to set it back to RAW when you are done!

If you are not familiar with these topics, then it would be better if you familiarized yourself with them before. There are a number of articles you can find that will take you through this of course.

What is infrared light?

Infrared light is light that has a frequency that is lower than the visible light in the spectrum. We can also say that the wavelength is longer than the visible light. Infrared light have various properties that are different from visible light and it reflects and refracts different from visible light through the camera lens.

Here is a diagram that shows how the infrared spectrum relates to the visible light spectrum. In this article we will only be talking about photographing in the infrared spectrum that is close to visible light, between 1200-730 nm roughly. Infrared photography in this aspect is not to be confused with heat signature cameras and systems such as FLIR (example below) which are used for example to detect body heat. There is also the “far infrared spectrum” said to have medicinal use and influence for example the production of vitamin D in the skin of humans and a few other species.

Radation in the thermal heat range and the far IR range does not really affect the result of IR photography as we have limited our reception range to the near visible light IR spectrum. The sensors in a digital camera is also not very sensitive in ranges under 1000 nm so it makes little sense trying.

This shows the spectrum of electromagnetic radiation. Source: Wikipedia Commons.

Looking at the picture above we can see that the visible light spectrum ranges from around 730 nm to about 370 nm. Above we have X-ray and gamma rays, nasty stuff to us humans but below is the infrared portion of the band.

Thermal Image of a Dog. Source: Wikipedia Commons.

Here to the left is a picture taken with a different technology (FLIR) that captures the heat radiated from a body.

We can here see the lighter areas correspond to hotter parts of the animal. This is a technique that is quite often used for tecnhical purposes such as trying to find leaks in insulations and heat pipes and similar.

This is known as thermal imaging but is the area around 100 µm and photographic sensors for normal cameras don’t work well in this range. This is however what most people think about first when subjected to the term “infrared photography” and it is important to distinguish between the two.

So the infrared spectrum we are interested in lies between the lowest portion of the visible light spectrum around 730 nm and down to perhaps something like 1200 nm. This light comes normally from very “hot” sources, such as the sun, or a light bulb perhaps.

Those of you who are physiscists may remember the black body radiation formula and put it to use here

In this picture it is possible to see the difference between the visible light spectrum and the IR spectrum. The left hand picture is shot with infrared filter and the right hand side is a normal visible light picture that has been shot in B&W

What is needed for digial infrared photography?

You need a digital camera, preferably an SLR type camera because we will be attachning an IR filter to the camera lens. Some point and shoot cameras also allow you to attach filters and should work similarly as the digital SLR type cameras.

Different cameras have different sensitivity for IR in their sensors. Some cameras will therefore need much longer exposure times than other cameras, and the results may be quite differnet depending on choice of IR filter and camera type.

This photograph shows what happens when a digital sensor photographs something with such an intense IR radiation that it overloads the sensor.

You will need a tripod to mount the camera on because a normal digital camera has a sensor that is so sensitive to IR light that the camera is equipped with an IR blocking filter just in front of the sensor.

This blocking filter is there so that IR will not disturb the normal function of the camera sensor. If a digital camera IR filter is saturated with IR so that some of it gets through and starts interfering with the normal imaging processing then we may get something like the photo to the left.

If you look at it you can see that the cinders are not in the correct colour, the sensor chip is “blooming” because of the extreme infrared radiation from this and if the camera did not have this IR blocking filter then any picture in daylight would suffer from the same problem.

What we will do now is to take a filter that blocks visible light and allows IR to pass through. This filter will be mounted on the camera lens and then even if the camera has an IR blocking filter we will increase exposure until we get a reasonable image.

We may expect exposure times between 5 seconds up to several minuted depending on factors such as, sensor sensitivity in the infrared range, the IR blocking filters effectiveness in the camera, camera ISO setting, type of IR filter being used on the lens.

To summarize, this is what is needed for digital infrared photography:

• Camera with lens suitable for landscape photography, a nice wide angle is a good starting point.
• An infrared filter. They are usually something like €60 and upwards depending on quality and the exact type.
• A tripod to mount the camera on because of the long shutter time.

How to set the camera up for IR photography

First of all there are a few things you need to know about IR light in order to set the camera up properly. IR light is not visible so it means you must actually work in the dark so to speak. When the IR filter is mounted on your camera you can not see anything through the viewfinder of the SLR camera.

If you have a live-view on your camera you might actually see something, it depends on how sensitive your sensor is to infrared light. An un-modified camera blocks most of the infrared light on the sensor with a blue filter so the levels reaching the  sensor is very low for this reason.

Tripod

Shooting IR with a camera that has not been modified for IR photography only needs to be put on a tripod or similar. You are looking at exposure times from seconds up to minutes even and this is not really something even the best would attempt hand-held.

A good steady tripod is therefore recommended and you should also consider having a remote shutter release connected to the camera. There are good IR remotes and there are also tethered release cables that are very useful. This way you do not have to touch the camera at all when exposing the picture.

If you do not have a remote release then you can use the camera self-timer. Set it for about five seconds, that shoud do the trick. Then when you press the shutter, the camera will wait five seconds, allowing the vibrations from your touch to subside before the shutter actually opens. Hence sharper prictures.

Mirror slap vibrations is not normally a problem with shutter times in the range of several seconds. The reason for this is that the vibration rings out so quickly that it will subside in the first 5% or so of the exposure, then for the remaining 90% the rig will be steady so it will not show much in the final picture. Mirror slap is mostly a problem with shutter times around 1/15 – 1/2 second.

Manual mode

You need to work most cameras in manual mode for this time since metering and autofocus will not work properly. You will have to rely on the histogram to make the exposure correct. Read more about the histogram here.

A starting point for my D70s in manual mode and nice sunshine is generally f/8 and 10s exposure time.  Then I check the histogram, determine how much under/over-exposure there is, adjust the exposure time to compensate and take a new picture.

Most of the time the second or third picture is dead on!

Getting it sharp

You will also need to know that your lenses focuses differently in IR compared to visible light. This used to be widely recognised and prime lenses had usually markings showing where the IR offset was. Take for example this lens, it is the Nikkor AF 50/1.8D lens which is a favourite for sharpness and good quality. This lens have a hyperfocal marking for f/11 and f/22 and it has a line to show where the current focus is set. On the side of this line is a small dot, this dot signifies the corresponding focal point in infrared!

To focus this lens in infrared you can focus it in visible light, check where the line is aligned with and then manually turn it so that the dot is aligned where the line used to be. Now you have achieved the same focus in the infrared wavelengths.

Since most lenses do not come with this feature these days – most of them have no hyperfocal mark and zoom lenses normally only got distance markings which generally only are correct at one focal length. So in order to focus properly we have to focus the lens either manually or find some way to make sure that we are in the focal range. To do this we can use a hyperfocal chart and focus manually, something that requires a bit of practice (and knowledge about hyperfocal charts and how they are calculated).

The second way is to use an aperture that gives a very deep focus. Using an aperture of f/8 or f/11 should be quite enough for most lenses. This means we can focus the lens before we mount the filter, then when the filter is mounted we leave it focused in visible light and because of the large focus depth we can assume that most of our picture in the infrared will be in focus anyway.

This trick is pretty good with wide-angle lenses and up to say 70mm focal length or so, after that you will have to experiment with manual focus since f/11 may not be enough. Going to a higher f-stop such as f/22 or f/32 can be done of course but there are limits to this because of the extreme shutter times you will have to endure. Most digital cameras don’t like more than a couple of minutes of exposure time, their sensors goes hot and starts showing hot pixels.

Infrared focus index

Some lenses have an infrared index mark on them. Today this is becoming rarer, but most older lenses do have this mark and if you look on your focusing scale you might be able to locate it. It is usually a line or dot in a different colour next to the normal focusing mark.

Lens with IR focusing mark. It is the round dot to the left of the normal focus line here. Most lenses focus closer in IR than in visible light. This is the Nikkor AF 50/1.8D lens, a very good choice for IR photography actually.

If you are using a zoom lens there is usually no IR index on the more modern lenses although some older lenses can have IR index markings for their shortest and longest focal length. When the lens is zoomed to something in between you will have to guess and estimate the actual focus point.

This is usually not a problem unless you are shooting the lens wide open. For example my 18-200/3.5-5.6 lens is pretty sharp no matter where the focus is set at the 18 mm end most of the time. When using this I just dial in f/8 in the aperture and I get pretty sharp pictures in IR as well.

If you want to experiment you can take a series of pictures with slight adjustment to the focus in between. This way you will be able to find the sweet spot for your lens at infinity for example and at a certain focal distance.

The IR index changes when you zoom the lens. If you find the sweet spot somewhere to the left of the normal focus at 20 mm then when you zoom it to 200 mm it may be very much different.

How to take the picture

Here is a procedure on what I do when I take the picture:

• Put the camera on the tripod.
• Set the camera to RAW mode. You will be needing to adjust the white balance in the post processing and this is best done in RAW mode.
• Dial in APERTURE priority mode and set the aperture to what you consider useful, something like f/8 or f/11 on a sunny day should be fine. The aperture mode is usually referred to as “aperture priority” on Nikon cameras and have the “A” symbol. Canon cameras usually have the “Av” marking instead.
• Compose your picture carefully and focus. You can use autofocus if you want.
• Put the focus switch to manual mode (otherwise the camera may try to re-focus after you put the IR filter on it).
• Take one picture without the filter.
• Switch to manual mode, this is usually marked as “M” on most cameras. Now we can set both aperture and shutter time manually. Leave the aperture at the same as you had before.
• Set exposure time to something around 10 seconds.
• Take a picture.
• View the histogram, if the picture is underexposed, increase the exposure time, one EV underexposure is double the time one EV overexposure is half the time.
• Take another picture and repeat until you have found a good exposure for your picture.

It is not so difficult once you have practiced a few times and it becomes a second nature. But remember to turn off autofocus or else the camera may start “hunting” for focus once you press the shutter release half-way down when you have mounted the IR filter on your lens. This will of course result in a very blurry picture.

Sorunda Church photographed in infrared. Slight colorization in the post processing.

When to use Infrared photography?

IR phtotography is at its best when there is an abundance of sunshine around. This will really bring out the special IR effect when using the IR filter as well as shorten the exposure times (unless you have a proper modified IR camera).

Normal visible light photography is usually best in the mornings and evenings as the sunlight comes from the side and lower at the horizon rather than shining straight down from above creating very harsh conditions.

But now you can use these times of the day since the light mid-day is perfect for IR photography and it makes it stand out. The contrasts is not a problem for IR the same as for normal photography in the same way.

Sometimes infrared gives very unexpected results. Take a look at this picture here:

This is an example of the IR effects that we can see. Her clothes here is actually black but not in the IR spectrum. A black sweather with white print, black track pants and a backpack that is black and rust red.

What to photograph

Green plants becomes white in IR so they are quite interesting and really bring out that special IR effect that you are looking for. Whater becomes very dark and moody, the sky is dark but clouds are very bright and because of this you can compose a lot of mood in the picture by using the following elements:

• Trees and foliage
• Water streams
• Clear skies
• Clear skies with a bit of cloud
• Stone walls, buildings, ruins

If the sky is grey and cloudy the IR effect will not be as pronounced but that does not mean that you can do it. Au contraire my friends, you should experiment. Winter landscapes and snow can be very effectful as well.

I have also found that stone buildings such as old churches, ruins and so on are very interesting to use for IR photography. Experiment and please leave feedback here on what you think about it!

Photographs in nature and in the city scape will be quite different in IR than in visible light so experiment with both there are many many interesting things to take pictures of.

You can also use IR photography indoors but the exposure times can easily be several minutes unless you are using a converted camera. This picture is a picture that I took in my kitchen where the exposure time was about 2 minutes and the only thing lighting the scene was actually a lamp in the window.

My kitchen in Infrared. Check out the plant in the window where you really can see the IR effect.

The post processing

The post processing of the images is a bit of a trick. Depending on what software you are using you may have to work to set the white balance right.

Infrared pictures straight out of the camera have very weird colours usually in the red end of the spectrum and in order to have colourized IR pictures you may have to set the white balance manually.

I am using Adobe Lightroom to post process my pictures and I have to set a custom white balance that is very cold, around 2000 K or so. Some softwares may not be able to go this low so you will have to work with this.

If you are shooting and going for B&W IR photos then this is not a problem since you can just filter the photo to B&W later as you want and it will be great, you then don’t have to worry about the white balance at all.

Unprocessed IR picture. This is straight from the camera (just converted from RAW to JPEG format for the web)

Infrared with whitebalance adjusted. Here the WB has been adjusted to around 3000 K. You can now see there are some variances in the red and blue parts of the spectrum here. I have deliberately not postprocessed the picture further.

Black and White IR. Here I have also neutralized the colours by shifting the green/purple balance and the result is an "almost B&W" rendition.

In this picture I have preserved some colour and enhanced it by increasing the saturation many times. It does give me a feeling of nuclear disaster or something... what do you think?

Convert your camera

If you are serious about infrared photography and wish to pursue this you can have your digital camera converted for IR photography alone. This means that the IR blocking filter inside on top of the sensor is removed and replaced by a filter that blocks visible light.

The advantage here is that you may still compose your pictures as normal, looking through the viewfinder now works as before, you can focus and work around most obstacles here and then when you press the shutter release you get and infrared photograph instead of the normal one.

Shutter times wiht this solution will be similar to normal visible light shutter times and you can use the camera’s noramal metering. You will have to dial-in some exposure compensation however, perhaps -1.5EV or something similar but that is not terribly different to visible light photography!

The back side is of course that your camera can then not be used for normal light photography.

And the focusing mechanism of the camera still works in visible light which means that you still have to take care of the focus offset. The focal point of the camera can be adjusted but only to a certain extent because different lenses at different focal lengths have different IR focus index points means that there is no simple fix that will work for all lenses at all focal lengths.

One of the best camera fixers out there is actually LifePixel [lifepixel.com] who can convert your camera or sell you a conversion kit if you are handy enought to do the conversion yourself. For less than $200 you can have a new hotmirror filter installed in your camera and then take IR pictures free-hand. Lots of people buy a spare body from Ebay or similar places (A D70 is a great camera for IR by the way) and have it converted while they keep their main camera unconverted.

I will be converting my camera when I invest in a new camera house.

Some more pictures

Here are some pictures that I have taken and I like. They have all been taken with a Nikon D70s and B&W 87C infrared filter. This filter removes all visible light and actually the top part of the near visible light spectrum also of the IR. This means that if you want to take IR pictures with more colour you should rather get a Hoya R72 filter or similar that works from 720 nm and down to about 1000 nm. This filter starts at around 830 nm and thus is better suited for B&W IR photography.

Lake muskan. This photograph has been post processed with a bit of colour added to it.

Grödinge Church in Infrared.

Railroad being built close to Segersäng train station in Stockholm. This is a combination of IR and visible light.

Church in Sorunda in IR

Stones in Ängsjö by the waterline. Because of the long exposure the water becomes very very nice...

Sundbyberg City. Infrared plus natural light in combination. A calm very serene picture emerges.

Flickr Refer Comment

This script allows you to put a small signature when commenting pictures that tells the people where you found the picture. It is a very nice feature and tells people where you are finding their pictures when you comment them – which group, if you are reading through RSS aggregator, in your friends and family collections and so on.

Flickr Buddy Icon Reply

This script allows you to reply with a buddy icon and / or name so that people know who you are responding to when making a follow up comment. Lovely script!

Flickr – Multi Group Sender

This script allows you to pick from a list all the groups you wish to send a photo to. Normally you have to pick one group at a time and from the organiser you can only send a nuber of photos to one group at a time but with this you can send one photo to several groups at the same time.

In order to use any of them you must first install Greasmonkey, a scripting add-on for Firefox that also can be gotten to work with Internet Explorer.

This article will start off on the D70s camera that I have, but should work very similar on most Nikon digital bodies. It may also be the same for Canon and other brands although I have not verified it. If you know, please leave a comment to this effect!

Most people are probably aware that in the camera CSM menu item #15 you can control what this button actually does. The obvious choices here are the following:

• Lock exposure and auto-focus at the same time (AF/AE mode)
• Lock only auto-focus (AF mode)
• Lock only exposure (AE mode)

What people generally do not know is that there are two more modes that are very useful in certain situations. These modes are:

• Auto focus ON mode (AF-ON mode)
• Flash metering off mode (FV mode)

They are not so well described in the manual and so you may want to practice a bit with using them! The rest of this article is to describe some situations where they are quite useful:

Auto-focus mode

This moves the autofocus from the half-way pressed shutter release button to the AE-L/AF-L button on the back side of the camera. Why do you want that?

There are several situations when this is handy. If you have pre-focused the camera and don’t want it to change focus you can prefocus with the AE-L/AF-L button and then keep pressing the shutter release. If you press it half-way the camera will meter but not refocus.

In the menu this is called AF-ON (auto focus ON).

With lenses that have VR (vibration reduction) pressing the shutter half-way engages the VR function (when it is turned on). This function draws lots of juice from the camera battery so it is a good thing to not engage when not needed. If you are using the AE-L/AF-L button for focus then you have managed to separate focus function from metering and VR function and thus you can use the auto-focus happily without using the power for the VR of the lens (and withoug having to turn it off on the lens side-button meanin that if you want to take the shot you can just do so, the lens and camera is ready).

Premetered Flash mode

This is even less obvious for most people. Have you ever used the Nikon i-TTL system to take flash shots of your pets? Then you know that the camera sends out a pre-flash to meter on just before the main flash is sent out. This makes cats and dogs and other animals with good reflexes to close their eyes and you end up with a picture that’s not so good.

If you scroll down the menu you will find an entry there that say FV-Lock. The way this works is ingenious. By pressing the AE-L/AF-L button you can control the pre-flash used to meter before the main flash is used. So this is what you will do:

1. Frame and compose your shot carefully
2. Focus automatically or manually as you prefer
3. Press the AE-L/AF-L button, the flash will flash and the camera will meter and remember the flash value.
4. Now, wait till the right moment and take the picture. The flash will go off without pre-flash and you will have a perfect picture of your pets!

This is also very useful when working with still pictures, it saves energy in the flash head and especially when working with a flash through an umbrella that means you may go much further on one set of batteries!

Remember that you need to do another pre-flash when you re-compose the picture, change angles or anything else that affects the light in the picture!

One of the most useful features of the digital camera is the histogram. This is a diagram that shows how you shot was exposed after you take it. It is invaluable to avoid over- and under exposure, but also when shooting in manual mode because just looking at the LCD is most of the time very difficult to see exactly how the exposure works.

How to find the histogram

This is different on different cameras. You may have to consult your manual. On most NIkon digital bodies you can do the following. Take a picture and press the “view” button so that it shows on the LCD. Then use the 4-way button, keep pressing the “right” on this button and it will cycle through various modes showing different information. When you see the following you have found the histogram:

What the histogram shows

D70 Histogram Page

As you can see the histogram shows the distribution of dark and light pixels in the picture. Some camera models has separate histograms for red, blue and green. My D70s has a single histogram showing the combination of these colours.

Notice the vertical red lines in the histogram? They are “f/stop” indicators. An f/stop is a doubling or a halving of the light that comes in to the camera. Looking at this histogram you can see that we are exposing pretty well. If the yellow curve is squashed to the left hand side it means that the picture is under exposed. If the histogram is squashed into the right hand side then you are over exposing the picture and need to decrease the shutter time or stopping down the aperture a bit.

How to compensate when you read the histogram

The way it is organized is that usually three “ticks” of the wheels that controls exposure / aperture is equal to the distance between two red bars. If you want to move your exposure curve up one “f/stop” (or 1EV which is a terminology I like better, it is the same thing, EV means Exposure Value).

If your histogram shows 1 EV underexposure then you can compensate by either

• Increasing the shutter time 3 “steps”, this should double the exposure time, for example if your exposure time is 1/250 s then 3 steps longer means 1/125 s.
• Opening your aperture, this means lowering the f/stop value, if your aperture is f/8 then three steps down is f/5,6.

There is also a third way to compensate for under exposed pictures. You can increase the ISO setting of your camera. The D70 camera normally works at an ISO setting of 200. Increasing this to 400 represents 1 EV also. Increasing to 800 is 2 EV.

How to work in manual mode

Start by setting reasonable settings. On a sunny day you may wish to start with say f/8 and 1/500s. When you look in to the view finder there is a coarse over/under exposure meter. It looks a little like this:

 3     2      1    + 0 -    1      2     3
< | | || | | || | | || | | || | | || | | >

There is a bar that shows how your current setting reflects the cameras own meter. If the bar is growing to the left (+) then you are over-exposing. Rotate your thumb or index finger wheel to change the shutter time or aperture until you are close to the middle (0) where exposure is judged to be correct by the camera. The numbers above the bar indicated EV or f/stops.

Take a picture.

Then take a peek at the histogram. How does it look? Does it look nice and centered or is is definitely sqashed to the left or right? If it seems that the exposure is wrong, try to judge by the red vertical lines how much. Then decide if you want to compensate by using shutter speed, aperture or changing the ISO setting.

When you have found the right settings this way take the picture you want. After each exposure check the histogram, compensate as you go, keep shooting. This way you have full control over the exposure in the camera.

This may take some practicing to get used to and to understand properly but after a while it will become second nature to you.

When to use manual metering

If you wish to take infrared pictures then you must practice this because with the IR filter on the camera it is not possible for the camera meter to work properly and this means that you can not use the cameras automatic metering. And because in difficult conditions when you are shooting the camera normal exposure compensation functions may be wrong, manual whooting will give you better pictures once you are used to it.

The only drawback here is that it may take a few seconds for you to find the correct setting for a certain scene to photograph. So if you are shooting some action shots you may be better of using the camera own metering.