Digital Still Cameras

We have point and shoot as well as Digital Single Lens Reflex (DSRL) cameras. We have three types of camera conversions. Depending on the camera model, different conversions are options.

UV+IR+Visible: The stock camera IR Cut Filter (ICF) and Anti Aliasing (AA) filter assembly, if applicable, is removed. A new clear optical window made from Schott WG280 is installed with the same refractive index. This special optical window is required else Auto Focus (AF) would not work. The camera will see from about 340nm to 1200nm which is the limit of the silicone used in the image sensors. We typically call the UV+IR+Visible coversions IR+Visible because the UV range is fairly narrow (350nm to 400nm) in comparison to the visible (400nm to 700nm) and IR range (700nm to 1200nm). New cameras that have Live View and Live View with AF are interesting because it means you can focus manually using the LCD screen whien using a filter that blocks visible light such as our UV pass or IR pass filters. Cameras like the Canon 450D that have Live View with a special AF mode using the image sensor can also AF when using a visible light blocking filter.

IR-Only: The camera is restricted to only seeing IR. A 715nm or 830nm IR filter replaces the stock ICF and AA filter assembly. Typically, IR-Only is used by a DLSR user who wants to be able to see through their lens normally yet have the camera take an IR picture. AF and Auto Exposure (AE) are compensated so that the DLSR user can shoot like normal. We can make some point and shoot cameras into IR-Only. With an IR-Only camera, you also have the option of using a more restrictive IR filter to get a more dramatic IR effect. However, when using an external IR filter on a DLSR, you will not be able to see through the camera and AF and AE won't work.

IR-Only 715nm. This is the most common conversion. At 715nm, the camera sees the about the same amount of IR light in outdoor sunlight as a stock camera sees visible light. If a stock camera can take a picture at 1/500 at F6.0 than a IR-Only 715nm will also shot at about 1/500 at F6.0. At 715nm, there are significant differences between the red channel and the blue and green. This means there are more creative options for IR color effects at 715nm such as the red-blue color channel swap that results in blue skies with white clouds and trees.

IR-Only 830nm. The 830nm is an interesting option for those who want a more intense IR effect and want a strictly black and white picture. After setting a custom white balance and/or equalizing color channel levels, the image will be almost completely black and white. One cost of an 830nm conversion is that you will lose 2 to 2.5 stops of exposure. You will have to set the exposure compensation on the camera for proper AE.

HR Visible: Only currently available on select DSLR cameras, the ICF and AA assembly is removed. A new ICF is installed because the stock ICF is cemented to the AA. The new ICF blocks IR light. By getting rid of the AA filter, also known as the Blur Filter, camera sharpness is enhanced by about 30% typically. The drawback on an HR camera is greater potential for moire patterns. The details on why the manufacturers put in a blur filter are technical, but, basically it has to do with digitally sampling an analog signal (Nyquist Theorem). The manufacturers are not willing to completely eliminate moire patterns because this would require a minimum 50% blur filter. So instead, they make a compromise which varies by camera model, but is often about a 30% blur. Interestingly, there is a digital camera being made that has no AA for this very reason - the Leica D8. When Shutterbug tested this camera in the spring of 2007, they found the sharpness on the 10 megapixel D8 was about the same as the Canon 5D which has 12.8 megapixels. This is pretty much in line with our observation of a 30% blur filter.

Which camera is the best for me or which one performs best?

We often get asked this question. The answer is not the simple because we need to know more about how you want to use the camera and how much you are comfortable spending. Do you already have an investment in DSLR lenses? Do you want a dedicated IR-Only body which is simple to use or would you like a more complex UV+IR+Visible DLSR. Or do you want a simple point and shoot camera that you can use like a normal camera or IR camera by changing the filters on the front?

All the camera sensors, CCD and CMOS, are based on silicone so they all have the same basic sensitivity to IR. However, the larger sensors have a greater surface area to gather photons so they have less noise and better IR sensitivity. Despite Canon's assertions otherwise, we have noticed a significant drop off in sensitivity from the Canon 300D to 350D to 400D. Those three cameras have the same sized sensor. The 300D has 6 megapixels in the same space as the 400D which has 10.1 megapixels. On our standardized tests, using the same lens and calibrated light box, we see shutter speeds of 1/60 second on the 300D and 1/30 sec on the 400D.

If you are trying to save money, a point and shoot IR+Visible+UV camera is probably the best choice. Since the point and shoot cameras have an Electronic Viewfinder (EVF) and use the image sensor for previewing the image, what you see is what you get. If you are shooting landscapes and want to use a DSLR with the least headache to take an IR picture, then a dedicated IR-Only DSLR camera is probably the best choice. If you want maximum flexibility to use your camera for Ultraviolet, Visible and IR work and are willing to pay the costs for extra filters and camera setup time, the an UV+Visible+IR conversion is the best choice.

Will my IR camera take a black & white or color picture?

It depends. These converted cameras do not know they have been converted. For all the camera knows, it is taking a normal color picture. Keep in mind that the reason these cameras can take a picture in the infrared is that the red, blue and green color dyes on the image sensor also happen to transmit light in the infrared. If you look at the blue dye light transmission curve, you will see the curve opens up in the blue and blocks out green and red. Then in the IR, the blue dye happens to open up again. The same thing happens to different degrees for the red and green dyes. This is why the manufactures have to put in an ICF in the camera. If they didn't, the camera wouldn't know if it was looking at blue light or where the blue dye happens to open up in the IR.

An IR-Only camera still thinks it is taking a normal color picture. If the camera White Balance (WB) is set to automatic, the camera will have a very red or purple looking image because the red dye is the most open to IR. If your camera can set a custom white balance using a white card, you will get a mostly monochrome image. Best results are going to be by shooting in RAW and then doing your color to B&W conversion in post processing software like Photoshop. There are many different techniques for IR post processing. We often see the red and blue channels switched so that sky are blue. Another technique is to throw out the blue channel because it is the least open to IR and hence the noisiest. Another neat trick is to use a IR+Visible camera to take a normal picture and an IR picture of the same scene. Then convert the IR picture to black and white and layer it behind the color picture. Set the transparency of the color layer to 30% and the IR picture will have the effect of creating dramatic highlights. Another interesting trick is to create various colored files in Photoshop, copy them onto a memory card, and use them to set different white balances.

Some common techniques can be seen at

A great tutorial on IR post processing is Andy William's technique at http://dgrin.smugmug.com/gallery/1111417

A good source for IR photography and post processing is from Lloyd Chambers at http://diglloyd.com/diglloyd/infos/GuideToDigitalInfrared/index.html

Please choose the camera from the list on the left.

Send mail to webmaster@maxmax.com with questions or comments about this web site. Last modified: August 25, 2008

Send mail to webmaster@maxmax.com with questions or comments about this web site.
Last modified: August 25, 2008