Thanks Andy.
Before starting with the B+W 091 Dark Red filter which I have confirmed as 0% at 600nm, 50% at 620nm, I thought I would go for broke and try the Hoya R72 on the D2X.
To give some understanding of probs I would have with the D2X this is what Bjørn Rørslett says of using it for IR
" You should not do IR with D2X. Simple message, simple remedy: Just don't do it. There are so much more satisfying approaches to digital IR than those available with D2X. On the other hand, the low sensitiivty to IR implies you may get less problems with skin tones, which are unduly susceptible to excessive IR. "
Finding an acceptable exposure took no time at all as I added 3 stops to the D100 mark. Settled on ISO800 - 4secs - f8.
Initially I set WB to Auto and the image is very red, and although I converted this to a B&W easily, I have been playing with various options for a Custom WB. Time taken out to find my manual and actually read it.
With the D100 I found far better results were obtainable with Custom WB taken from sunlit grass. The D2X set to the same gives reasonable results, but after the simple route processing as mentioned in post 44 I had to remove a blue cast and tweek it in curves. Left and right edges of the frame taken with the 35mm lens had to be cropped as they have an odd look. The 20mm lens that is brill on the D2x in visible light, and excellent on the D100 in visible and IR, suffered significant probs in bright areas at the edge of the frame on the D2X in IR. Enough not to use it for these experiments.
Attatched is the first false colour image from the D2X. The fence which came out light brown on the D100 is not so good and shows the blue cast well.
Next up I will add a polariser which on the D100 removes most of the false colour leaving a near B&W image.
Don
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