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07-06-2022, 12:01 PM   #16
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QuoteOriginally posted by Wheatfield Quote
Interestingly enough, there isn't a whole lot of visual difference between an image shot with an IR converted camera and a software conversion from a non converted camera. They aren't the same, but the effect, visually, is.
You mention "software conversion". Are you referring to the Pentax camera IR filter option in the B&W jpeg style?

07-06-2022, 12:12 PM   #17
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QuoteOriginally posted by biz-engineer Quote
You mention "software conversion". Are you referring to the Pentax camera IR filter option in the B&W jpeg style?
Photoshop. Feed it an out of camera raw image and hit convert. IIRC, it even gives a few options for the filter wavelength it is emulating.
I'm sure it would gag a purist, but for those who are just going for artistic effect it's fine.
07-06-2022, 09:49 PM   #18
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QuoteOriginally posted by Wheatfield Quote
I'm sure it would gag a purist, but for those who are just going for artistic effect it's fine.
I use Pentax IR option in B&W, I like the effect, but I don't like the very noisy skies. I don't know why, but IR skies are very noisy OOC. I've tried to emulate IR with SP10, but it's not quite as good as the software filter in Pentax K1. And I don't want to convert my K1 just for IR. So, I was thinking of buying an IR filter (~150 euro for 100mm square IR 720 filter), but I was concerned with sharpness of images when using an IR 720 filter without converted camera.
07-07-2022, 09:23 AM - 1 Like   #19
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QuoteOriginally posted by biz-engineer Quote
I use Pentax IR option in B&W, I like the effect, but I don't like the very noisy skies. I don't know why, but IR skies are very noisy OOC. I've tried to emulate IR with SP10, but it's not quite as good as the software filter in Pentax K1. And I don't want to convert my K1 just for IR. So, I was thinking of buying an IR filter (~150 euro for 100mm square IR 720 filter), but I was concerned with sharpness of images when using an IR 720 filter without converted camera.
I don't do infrared in any amount, I really consider it to be more gimmick than anything else, hence, I suppose, my satisfaction with software conversions in Photoshop. For me infrared is in the same category as making huge prints, in that if the image isn't strong enough to stand on it's own, make it look important.



07-07-2022, 09:50 AM - 1 Like   #20
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Apparently, older DSLRs do better with a lens filter. They are more sensitive to IR. Later models had better IR blocking. Good for IQ but not for special use cases like this.

Ideally, you want a body with a CCD sensor. The Pentax *istD line comes to mind. They are dirt cheap these days.

I have to admit that I have a *istDL and an IR filter that has seen little use. Time to get it out and try it again. My initial efforts were not great.

Here is one I made earlier. In practice, it is quite fiddly. First of all, forget about auto focus. Even manual focus is difficult with the filter on. I set the camera on a tripod, focused and reset to the IR marking on my old school lens. In this case it was an SMC Pentax 50mm f/1.4 I think (but my memory is a little fuzzy on it). I then put the filter in place and tried a few exposures until I found that that worked, more or less - in this case 1/6 sec, ISO 400 and f/11. One could pre-focus, I guess, but I have not tried it yet.

07-07-2022, 10:10 AM - 2 Likes   #21
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I agree in that IR seems to be a gimmick, best used sparsely. For now I'm having fun with my converted K-5 (until the gimmick wears off a little I guess).
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07-07-2022, 11:05 AM   #22
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QuoteOriginally posted by newmikey Quote
I agree in that IR seems to be a gimmick, best used sparsely. For now I'm having fun with my converted K-5 (until the gimmick wears off a little I guess).
Colour infrared seems to be something Photoshop doesn't have an emulation for. OTOH, when I think colour infrared I think of the old Ektachrome infrared and it's orange coloured foliage.

07-08-2022, 08:39 AM - 3 Likes   #23
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True IR photography records things that are otherwise not seen. Running a normal image through some software chicanery is just not the same thing.
07-08-2022, 09:30 AM   #24
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QuoteOriginally posted by Wasp Quote
True IR photography records things that are otherwise not seen. Running a normal image through some software chicanery is just not the same thing.
In this case if it looks like a duck and quacks, it doesn't really matter if it's a cormorant.
07-29-2022, 06:06 PM - 1 Like   #25
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I had trouble getting sharp photos with filters on a standard camera setup, so I bought a second-hand Fujifilm X-A3 with full spectrum conversion. This means that I now have full access to any IR, UV or other images, depending what filter I screw onto the camera. I also have the same model camera unconverted, so I could do some comparisons if I wanted, but the converted camera is just so easy. The advantages of the converted camera are the obvious - like being able to shoot handheld at 1/200s instead of 10 seconds - and three others that really help with IR photography:
1. I can leave the white balance at the same setting
2. Autofocus and focus peaking both work very well and are reliable with the Fuji kit lenses and with vintage MF lenses
3. The EVF is much more useable.

The camera arrived a few days ago, and I am housebound in CoVid isolation, but I have a window I can view both vegetation and sky. Here is one of the first five shots I took without even looking at the camera settings, handheld through that window with my Super-Takumar 24mm f3.5 and a 680nm filter. This jpeg has been converted to high-contrast B&W using Photos (the trivial software in Windows) built-in function. The image is sharp enough to surprise me after weeks of experimenting with filters on my unconverted X-A3.

So now I have a 24MP IR camera which gives great shots and is easy to use. I have two filters, 720nm and 680nm, and I will also play with a 25A red filter. Next step will be to get suitable processing software - probably Raw Therapee, and watch all the Rob Shea videos on youtube to start on color-swapping.

In summary answer to the original question: yes an unconverted camera can give good quality images if you are well set up and know how your lenses work with the IR filter, but a converted camera is incredibly easy to use and has a massively-higher success rate.
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08-02-2022, 10:28 PM   #26
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QuoteOriginally posted by Gary H Perth Quote
This means that I now have full access to any IR, UV or other images, depending what filter I screw onto the camera.
I am sure your converted camera was not modified in such an extend to allow UV photography at its max (<400 nm), because infrared conversions are done without replacing sensor's own protective glass that absorbs UV (especially UV-C and UV-B region).
On the other hand you need special lenses for UV photography, because ordinary lenses have anti-UV coatings.
IMO "Full spectrum" conversion in most cases is VIS+IR conversion.
08-03-2022, 05:48 AM   #27
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QuoteOriginally posted by Medex Quote
I am sure your converted camera was not modified in such an extend to allow UV photography at its max (<400 nm), because infrared conversions are done without replacing sensor's own protective glass that absorbs UV (especially UV-C and UV-B region).
On the other hand you need special lenses for UV photography, because ordinary lenses have anti-UV coatings.
IMO "Full spectrum" conversion in most cases is VIS+IR conversion.
My conversion is a Kolari-Vision, which is marketed as being able to deliver UV photography when combined with both a suitable lens and a UV-pass filter. It'll be a long time before I venture into UV, I have too much to learn on IR first. Way in the future!

But here is a quote from their website on UV work: Our filter has a 50% transmission peak at 365nm, and >25% transmission between 340-380 for high total light transmission.
08-03-2022, 10:59 PM   #28
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QuoteOriginally posted by Gary H Perth Quote
My conversion is a Kolari-Vision, which is marketed as being able to deliver UV photography when combined with both a suitable lens and a UV-pass filter. It'll be a long time before I venture into UV, I have too much to learn on IR first. Way in the future!

But here is a quote from their website on UV work: Our filter has a 50% transmission peak at 365nm, and >25% transmission between 340-380 for high total light transmission.
315-400 nm is UV-A region. 50 percent transmission (at 365 nm) is very low.
I would possibly use this Schott N-WG280 glass for full spectrum - transmission at least 90 percent in 300-2700 nm
https://productimages.edmundoptics.eu/8776.PNG
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