Originally posted by Bob 256 What you say about using longer wavelength cutoff filters with a 590nm converted camera is true. The reason for doing the full spectrum conversion is that it allows one to still use the camera for regular use with a UV/IR reject filter on the lens and it also allows UV photography if one so desires. Also, if just IR illumination is used (e.g. surveillance photography) there is a slight gain in the camera sensitivity because the 590nm filter in the camera is eliminated (no filter over the lens is needed since all the illumination is in the IR range).
Yes, both of those options are very niche IMHO which is why I said they are "for some specialized application" but technically you are absolutely spot-on.
Quote: The context of the "clip-in filters" was for lenses that couldn't accommodate over the lens (front) filters which is the case with some ultra-wides and others. Then, the only option is a behind the lens filter (or in some cases, a very large front filter in a mount),
And I think that is not necessarily true. Once you have decided on a wavelength, a sensor conversion to that particular wavelength allows you to use all of your lenses without front filter at that specific wavelength and some lenses which do take filters at any given (longer) wavelength as well through the use of screw-in filters. As I have no noticed, some UWAs don't do all that well in infrared to begin with. I had high hopes for my Sigma 8-16 (which indeed does not take filters) but it failed the cut miserably. The 8mm fisheye does a little better (and also does not take a filter) but the Tamron 10-24 and the DA16-85 really perform OK under infrared light and both take reasonably-sized filters (77mm and 72mm respectively so a step-down ring is also quite possible).
Quote: ...and I agree that "clip-in" filters aren't the best option. Gel filters are best and they are so thin, they don't have significant issues with reflection or optical path lengthening, and degrade the image very little. When I use these, it's with a specific lens that is already prepped with the filter, so it takes no longer to install that lens on the camera than any other.
That is an interesting use case indeed, never had a chance to use gel filters myself. If I read between your lines, I should probably stay away from them, fumbly-fingered as I am
Price comparison:
I see a complete set of STC 590,720, 850 and IR/UV-cut clip-ins costs $370 - even if I ignore shipping costs, import would add on 21% VAT and clearance handling charges. Total would end up somewhere around the €470. I would probably only do that if I'd have converted my main body (KP) to infrared instead of having bought a converted K-5. For that amount, I can buy an additional preconverted K-5 with a different IR sensor filter than the one I already have or buy about 5 large diameter IR filters.
So, marketing aside, these clip-ins seem to have a very specific and narrow use case scenario with a questionable CBA. It's great to have that option but it seems absolute overkill for most. But I may be totally wrong of course, no idea how others tend to evaluate their use case.