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Author Topic: IR filter choice  (Read 602 times)

bwana

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IR filter choice
« on: January 12, 2020, 05:32:42 pm »

Has anyone experienced 'lesser' quality IR filters - fotga, Tiffen($19) vs Hoya($38) vs B&W($75)?
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smthopr

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Re: IR filter choice
« Reply #1 on: January 14, 2020, 01:06:22 pm »

Has anyone experienced 'lesser' quality IR filters - fotga, Tiffen($19) vs Hoya($38) vs B&W($75)?
Do you really mean "IR" or do you mean "UV"?  There's a big difference.  Maybe if you say why you want the filter, that would be helpful.
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rdonson

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Re: IR filter choice
« Reply #2 on: January 14, 2020, 05:12:11 pm »

are you only interested in screw in filters?

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Ron

smthopr

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Re: IR filter choice
« Reply #3 on: January 14, 2020, 08:07:53 pm »

Do you really mean "IR" or do you mean "UV"?  There's a big difference.  Maybe if you say why you want the filter, that would be helpful.

I'll just add this:  People often use UV filters to "protect the lens" rather than really alter the image.

IR filtration becomes important when using heavy ND filters on digital cameras.  If the IR is not reduced, it will contaminate the image when using heavy ND filters such as 6 or 10 stop filters.

I will say that I've used the Breakthrough IR/ND filters with good results and not too much color cast.  I've used, older Tiffen IR/ND filters for motion picture work that had a very significant ugly yellow cast and I would avoid these.

If you're just looking for UV filters, I suspect any good quality filter will be fine.
On the other hand, good IR/ND filters can be quite a bit more expensive, but necessary.  I had found the Breakthrough filters by doing some googling and reading tests and reviews online.
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bwana

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Re: IR filter choice
« Reply #4 on: January 15, 2020, 11:38:24 am »

I have an ir modified Fuji (integral filter removed) and I want a deep ir filter (pass wavelengths >790 only) in the old Days I used an 87b (wratten?) but now with the trans sensor as well as the potential issue of unwanted reflections, I donít know if the expensive multi coated b&w makes much difference.
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smthopr

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Re: IR filter choice
« Reply #5 on: January 15, 2020, 01:15:04 pm »

I have an ir modified Fuji (integral filter removed) and I want a deep ir filter (pass wavelengths >790 only) in the old Days I used an 87b (wratten?) but now with the trans sensor as well as the potential issue of unwanted reflections, I donít know if the expensive multi coated b&w makes much difference.
Ah, this is an interesting project!

I would think you would want a filter with good coating to minimize flare and reflections.  The difficult part will be how well the filter removes the IR for your sensor.  I would think here, it might be helpful to contact the filter companies and ask their advice.  You might also consider testing a few brands on a sunny day and see which works best with your IR sensitive camera.

Have you found sources for IR filters that do not also have ND built into them?
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bwana

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Re: IR filter choice
« Reply #6 on: January 15, 2020, 03:03:28 pm »

You misunderstood- the filter only passes ir. There is no nd
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smthopr

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Re: IR filter choice
« Reply #7 on: January 15, 2020, 08:04:40 pm »

You misunderstood- the filter only passes ir. There is no nd
I understand.  But who makes such a filter?  There were some Tiffen filters that had poor color rendition.  And there were also
"hot mirror" filters for the early RED digital cinema cameras.

Ah, but maybe I have misunderstood.  You want the filter to shoot IR images, without visible light contamination? In other words, you want to filter all light EXCEPT IR?

Or... you want to shoot your IR sensitive camera in normal light?  I'm guessing I was thinking this backwards :)
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Bruce Alan Greene
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mcbroomf

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Re: IR filter choice
« Reply #8 on: January 16, 2020, 05:35:03 am »

I would suggest that you get in touch with some of the companies that perform full range spectrum camera conversions.  Nearly all of them do this with the thought that the body can be paired with an IR filter to make it an IR camera (as well as a UV camera or a normal camera if paired with the right filters).   You also have to choose the IR wavelength as I'm sure you know and they may have recommendations for brands as well.
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Ken Doo

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Re: IR filter choice
« Reply #9 on: January 16, 2020, 09:49:11 am »

Filter quality does make a difference for IR filters just the same as for normal photography filters.

I like the AR coated Kolari Pro Slim filters.  https://kolarivision.com/

I use these for my full spectrum Fuji GFX 50S.  https://forum.luminous-landscape.com/index.php?topic=133308.0

Ken

bobfriedman

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Re: IR filter choice
« Reply #10 on: January 17, 2020, 08:13:30 am »

I would contact UVIROPTICS.com he sells IR Schott glass in any ring size.

see attached for B&W filters which you can get at most big on-line sources (e.g. B&H, etc.. )

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