IR/ND/Hot Mirror Matrix...

[Evin Grant]

Just to let you all know, I'm going to be conducting a test of all the currently available IR cut solutions for the the Red One next week.
This will be a controlled test done in LA daylight.
Tiffen, Rosco and Pancro have agreed to participate and I expect to hear back from Schneider Optics shortly.

My plan is to test for:
IR cut effectiveness both singly and in combination
Color balance/cast
Spectral response
The dreaded black Nylon magenta shift
Skin tone rendition
Foliage rendition

Do any of you have any other suggestions for specific things to test for?
Thanks,
E.

 

[Elizabeth Lowrey]

No suggestions, but I'll definitely wait to read your results before committing to a filter purchase. Great of you to do this and share it with the community, Evin.:wink:

 

[Tobias Straka]

That sounds great, thanks for doing this!

 

[Adrian T.]

Great move! Thanks a lot!

Please also test the following points:
- off axis response (steep angles)
- color and strength of reflection back into the scene

 

[Zach Hilton]

No suggestions either, but I sure do hope Schneider is available to be tested. That's the one I'm most interested in but it will be nice to have some real-world tests. I heard a bunch of competing information at NAB from all the vendors regarding whether or not you can stack IR ND's, at what strength should they be IR ND's, who's is optically superior, etc... Good luck.

 

[Joel Kaye]

Do any of you have any other suggestions for specific things to test for?

Since someone mentioned to me they were getting more accurate red tones under tungsten lighting with an ir cut filter on I'd be interested in a no ND tungsten test too. I didn't think there would be any effect, but maybe I'm missing something.

 

[conrad gaunt]

also, thankyou for offering to share the info, it might be invaluable.

 

[Michael Lindsay]

Hi Evin

Please consider testing wide lenses as well (maybe something in the 12-18mm range).

Hot mirrors 'seem' to work best for a narrow angle (hence 45degree and 90 degree versions)..

I suspect absorption filters are different?

thanks

Michael Lindsay

 

[Evin Grant]

Great move! Thanks a lot!

Please also test the following points:
- off axis response (steep angles)
- color and strength of reflection back into the scene

Please be more specific, Off axis from what? The lens? The sensor?

 

[Bruce Allen]

Evin, great idea.

BTW, take a look for slight color shifts appearing as turquoise vignettes on the wide angle lenses. Adam Wilt found that when he did his IR filter tests (example in the 2 last pictures):
http://provideocoalition.com/index.php/awilt/story/schneider_ir_filter_tests/P1/

Might not be too much of a problem, but keep an eye out for it...

Bruce Allen
www.boacinema.com

 

[Mike Prevette]

From the lens Evin.

Most of the evaporated metal IR filters start to effect the visible spectrum if light is passing through them at steep angles. So corners start to turn cyan, on wide angle lenses.


if you guys go back to my original IR page, I clearly show examples of the effect.

middle of the page here:

http://www.reduser.net/forum/showthread.php?t=9412&page=2

 

[Mike Prevette]

Also not to pimp my original test, but the thread did turn into a very worthwhile read. I would recommend a quick browse of it before you test, just so you can separate the knowns from the unknowns.

 

[Bruce Allen]

Mike, your thread was awesome and it's a crime it's not a sticky.

Bruce Allen
www.boacinema.com

 

[Evin Grant]

Will do Mike, Bruce.
Thanks for the info, it should be an interesting day.

BTW Schneider is on board now.
Looks like I'll have all the players on the field.

 

[Ketch Rossi]

Great Evin, look forward to your tests.

BTW, how was Dubai?

ciao

 

[Evin Grant]

It was awful:biggrin:

 

[Joel Kaye]

It was awful:biggrin:

Dude, that sucks. Tough break. If you need to bail out of the next one and want a replacement let me know.

 

[Ketch Rossi]

Well since it was that awful!!! I imagine you wouldn't mind going back some time soon with me to shoot the Pilot for my Dubai TV Series.

Will call you soon, and I want, must, like, love to see what you have shot this time.

ciao

 

[Michael Morlan]

Evan,

Glad you were able to get connected with Joel at Rosco. Looking forward to the comparison.

Best,

Michael

 

[Brook Willard]

Great Evin, look forward to your tests.

BTW, how was Dubai?

ciao

Yeah, Ketch, it was rough. Barely survived.