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How to remove the IR cut-filter from the Olympus 2040




Be sure to read my modding disclaimer here before proceeding.


Before you start disassembling your Olympus, you should make sure you find a suitable replacement glass for the filter. Why? Because without a parallel plate replacing the filter, your camera will be very near-sighted. How much you ask?

This was shot with focus set to infinity!

To understand what influence the plate has, you might want to visit http://www.haw-hamburg.de/~schramm/lehre/physik/phys_1/maple/html/goptik16.html. It is german, but the pictures speak for themselves.
Ok, now that it is clear that we need a replacement, what dimensions should it have?
The filter I had in my 2040 had dimensions (updated): 9.925mmx8.925mmx2.775mm (Charles measured his to be 2.87mm thick)
I am sure that there are specialist companies which can produce glass in any dimension. However, I have no idea what it costs! Luckily, a small shop close to my university sells material for chemistry and biology. They had a high-grade microscope slide / object holder. This glass is of high quality (very parallel) and very cheap, less than 1 Dollar / Euro per carrier plate. It was about 0.1mm too thin (2.65mm) but it works. Problem here is that the glass is not coated which may result in flair showing or chromatic aberrations increasing. Also, the glass is just clear. It has no colour tint as the filter we are about to remove. This can partially be dealt with via white balance correction and post-processing.
If/When I find another possibility that's closer to the original glass, I'll post it here. If you know such a possibility: Please contact me!


If you can obtain a piece of glass with nearly correct thickness but too large in the other dimensions, do not despair! Use a good glass cutter and first cut a strip of glass as long as your raw plate is wide and a bit wider than the original plate. Now cut this strip again to a dimension once again a bit larger than the original.

Here is what I recommend:
  1. scribe line 1
  2. scribe line 2
  3. carefully break the glass along line 1
  4. carefully break the glass along line 2
To achieve better matching to the original, use a mini power drill (like a Dremel) and under running water sand away the excessive material. Hold everything in a way that the water spills away from you. Reason: The water carries very tiny pieces of glass with it. So you must use eye protection! If you don't do it under or even in water, the very fine glass dust will be all over you and your room, this is even worse.
If you scratch the glass, start over again, it is not worth inserting a damaged glass into your camera. If you feel safe that your camera will not collect dust, you can first remove the IR filter from it and then constantly compare the new glass to the filter. Otherwise, you'll need a pretty good vernier caliper to be sure that your new glass will fit the dimensions you obtain from me or another source.
Then slightly round the edges under running water with a piece of water-proof sanding paper. Just so much that they are not too sharp.

Please have a look at Don Ellis' excellent guide to glass replacement! www.kleptography.com/notes-irconvert.htm before starting.

For disassembly follow the instructions on my disassembly page. However, if you "only" want to remove the IR blocking filter, there is no need to remove the rear panel. When you have reached the CCD sensor, take out the filter. Replace it with the piece of glass you just made. Avoid any finger prints and dust as well as static electricity biult-up!
Then put everything back together. If anything does not fit, don't force it. Make sure that no cables are trapped between the housing halves. Don't forget to reinsert any doors and hinges that might have fallen out.
Now put batteries and a SmartMedia card in and that's it:
You just built your very own Olympus C-x0y0IR!
You may now go hunting invisible light!

Final remarks:
If you have read my (or anyone else's) introduction to infrared photography you know by now that IR light can contaminate your visible light photos. Although my white balance comparison showed that you can get quite good results with custom white balance on at least my 2040IR, there is no denying that this contamination is there. So what to do if you want to photograph visible light?
There are aftermarket hot-mirror and IR cut-filters available. They screw onto your lens thread just as normal filters do. They are for example available from Heliopan. However, these filters usually have no colour tint. This means that becausde we have removed this cyan glass, the colours are off. Either use manual white balance or -much better- a corrective filter. www.Schott.de offers several glasses that might work as does www.edmundoptics.com. Sadly, the only one I know to work is the X-NiteCC1 sold by www.maxmax.com in only a few selected sizes.

Perhaps you already know that each colour of light as slightly different behaviour when it comes to refraction. If you ever heared of chromatic aberrations: This is caused by this phenomenon. However, most lenses are corrected to remedy this problem by using ED glass. However, as normal cameras only see very little IR light, there is no need for the manufacturer to correct the lens for IR light. The further you wander into IR regions, the more problems will show. There are a few dedicated IR lenses out there for use on SLR cameras. They are corrected for example from 400nm to 1000nm (blue to infrared). Some SLR lenses have a red dot on the focus ring. This is the IR sharpness point or whatever it is called. IR light focusses behind the film plan (or CCD chip) when capturing IR light with a normal lens. By focussing "in front of infinity" this problem can be solved relatively easy but not as perfect as with dedicated IR lenses.

So, how strong is the Olympus IR cut-filter anyway?
See here:
  
Left one visible light with my standard 2020, right one with 715nm IR pass filter, using my Olympus 2040IR.
Pretty impressive, isn't it?

For more IR cut-filter comparisons, visit my page about my Minolta dimage D7 conversion.

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