What filters do you need for Red? A beginners' guide.

[Lawrence Daufenbach]

Do you need IR+ND combos when shooting on the red? Also what if you stack and ND3IR and and ND6IR? Is that too much IR going on? Trying to understand it better. Or is it better to have separate ND filters and an IR filter?

[Pawel Achtel]

Do you need IR+ND combos when shooting on the red? Also what if you stack and ND3IR and and ND6IR? Is that too much IR going on? Trying to understand it better. Or is it better to have separate ND filters and an IR filter?

It depends what you mean by "better". It all depends. The goal is to get rid of IR contamination and avoid side effects such as vignetting or colour shifts. Different solutions work on different principles. Dichroic filters cut off certain spectrum. Pancro mirrors, for example, reflect both visible and IR equally and therefore can not be separated into IR and ND filter.

Performance of a dichroic IR filter will also differ depending on the angle of your lens as they introduce cutoff frequency shift towards corners. Some users reported reflections when using Pancros. Mine seem work perfectly on the lenses I have.

Read the tests performed here, test yourself and then chose what works best for you and your lenses.

[John Heaney]

Hi Guys, I have a RED T3 18-50mm and 50-150 Zoom lens. Should I use a screw fit filter to protect the glass? if so, which one?

Thanks,
John

[Evin Grant]

Wow, way to resurrect a thread. I would recommend a matebox and 4x5.65 size filters for versatility and coverage. Most of us only use protector filters or optical flats for FX work where there is debris flying at the camera.

[Richard Foster]

Yes - I learned that the hard way shooting a sparkler on an 8x10 Deardorff with a 10" Rodenstock lens that ended up with an area of melted glass on the front element from a flying piece of molten metal. I sold that lens - at a loss:–(

[D Fuller]

Yes - I learned that the hard way shooting a sparkler on an 8x10 Deardorff with a 10" Rodenstock lens that ended up with an area of melted glass on the front element from a flying piece of molten metal. I sold that lens - at a loss:–(

A big loss, I'm thinking. Ouch.

[Richard Foster]

Yes, but that's why we're called "trained professionals." We have experience, and experiences, which is experience picked up the hard way.

[LCamak]

This is a very good thread but I am wondering if any information needs to be updated in light of the MX sensor? This thread started long before that.

Also, many operators have some extensive time under their belt now with the filter combos they bought. Any thoughts on what they'd have done / purchased different? What are the current reccomendations for "must have" filters? And brands please?
I'm adding a 6x mattebox for some anamorphics and I am re-evaluating what I need to pruchase this time.
Thanks!
lael

[JamminJG]

Hardly any mention of a Hot IR filter. In the oldnen days, long long ago, before time was measured, one used to have to have a "hot IR" when shooting at elevation. I live at 7000 and that's a "thing" out here. Our sunlight is closer to 5800k than 56 and we have uv bouncing all over the place... So, the question is: Is that still an issue with the new sensors and with the Epic and/or scarlet?

Inquiring minds need to know!

thanks

[David Jean Schweitzer]

I only use Hot IRs when I pile on a lot of ND. The theory behind this has to with the ratio of visible light to IR. When one knocks down the visible light by a major amount using ND filters you do not reduce the IR. The atmosphere does absorb much of the IR at sea level. At 7000' of elevation there will be more more IR than at sea level. In answer to your question about the newer sensors, yes they are less sensitive to IR than the pre MX RED One sensor. Nonetheless, like I said once I starting adding significant amount of ND combined with high altitude I add a HOT IR dichroic in the filter stack.