Thats cool that they make the a350 external filter. You are right about the custom white balancing in RAW, I was unable to do this on the cameras I tried because they were point and shoots that only shoot JPG. The issue I ran into was that the tiffen hot mirror was not even close to the cameras internal filter, and no amount of white balancing in camera would ever recreate correct color for visible light, but if you had manual control in a RAW editor you could probably get it right.
The one possibility for a combo camera would be if Sony offers a RAW capable camera (hopefully interchangeable lens as well) that has Nightshot. With the Sony H50, it was possible to disable the normal function of nightshot with a firmware hack, and then you could flip the internal hot mirror in any mode of the camera and shoot some fairly nice IR photos.
Personally, I find it easier to switch lenses than filters - they are easier to hold on to and harder to get scratches on IMO, so I like to avoid using my external filters when I dont need them.
The one scenario I could see my self using a "full spectrum" cam with external filters would be if I needed to pack light and thought theres a possibility I will want to shoot IR on occasion, but I think I would still prefer having two separate cameras if at all possible. You know, you could fit two NEX-5's and all 3 NEX lenses in the same space as 1 a700 and 2 lenses
On one hand, it would be really great if a manufacturer offered an IR camera, but then again, it might make IR a lot less of a niche. Most people appreciate what can be done with IR to some extent, but few people are willing to buy a camera and "sacrifice" it for IR only shooting. It is an expensive and scary prospect for sure, not knowing if you will even enjoy shooting IR, or whether results from that particular camera will be any good until its too late. I kind of like the fact that not many people shoot IR, and for pro IR photographers, this is advantageous too.
I bought my a350 knowing that I was going to convert it to IR, even though my main camera at the time was the a100. Looking back, I wish I would have waited until they slashed prices on the a700 last year and had one of those converted for about the same total cost as the a350. Thats not to say I'm unhappy with the a350, the a700 is just a big step up from it.
It is great to see more people converting a-mount cameras.
Anyhow, enough rambling from me!
Greg
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