BTW, Tom's pictures above remind me of another phenomenon I'm not sure whether somehow related to the IR problem: while the blacks of fabrics (and alike) materials tend to show brownish, I've noticed that black and "cold" materials (like polymers, or glossy leather) often adopt a somewhat greenish hue (I'm NOT talking about the frame extremities, coincidence angle side-effect of the IIR cut filters; also, this happens in daylight as well, while the IR contamination is most pronounced with tungsten lighting).

Anyone noticed that?

Yes, the first one is a lot cooler and the second on the warm side.

Tom (edited.. originally said Steve), I would say the difference between your two shots is down to 3 things. The white balance difference (as has already been discussed), the fact that the cameras are shooting at different angles relative to the sun and the different colour matrices the two cameras use. If you colour balance the images in Photoshop they both come out looking remarkably similar, including the blacks. IR contamination is much less of an issue under sunlight anyway.

Thanks Alister, but these are not mine... LOL
They were posted by Tom roper.

I agree about IR in daylight is not that much of an issue.

OOPs my apologies Steve! This thread is just toooooo long :)

Steven (or anybody), would gelling a tungsten lamp to raise the color temp possibly reduce the IR contamination problem? For example, if you were shooting an indoor interview and there was a lot of ambient light getting into the room, would adding a CTB or 1/2 CTB reduce the IR any at all?

Dave, I imagine it would, but by how much, I'm not sure.

It would be great for someone to set up a test tunsgsten with increments of CTB and compare the results.
Or just plain tunsgsten bulb (white balanced), then switching lights to daylight balanced bulb (white balanced).

If this has already been tested, I would be interested in the results.

I'd be willing to try it if I can get some time in my buddy's studio some time soon. I'd be testing this with a Lowel Rifa light so I'm not sure what effect the diffuser panel would have. When I first got this softbox, I noticed right away that the black baseball hat my subject was wearing came out as a very dark brown so I guess the diffuser panel doesn't block IR to any appreciable degree. I might test this with one of the FL heads that can be swapped on the Lowel light too......if I can get my hands on one! ;-)

First of all, I agree with Alister (and others) that in sunlight, the IR is not a problem, really.

For indoors, my Sony LED light (5600K) also allows to avoid it almost completely, but it's ugly on human faces.

I'll repeat my question; is the greenish cast to "cold" blacks (equally seen here in sun and tungsten light) also related to the IR contamination ? Did anyone notice that?

I think I mentioned it before in this tread, I took a picture of a Black metal chair covered with black matérial.
The tissue is brown instead of black but the metal parts legs and backrest came out perfectly black

So personally I would think that the greenish issue you are mentioning has no common ground with the IR problem

When I give it another thought, perhaps you're right it's not so much metal, but other "specific" black materials that tend to adopt the green tint I mean; for instance my desk chair covered with nylon "net", or PC loudspeakers' nylon grills...

Ryan ...
 

It appears the 77mm (stock #: 68-121077) is not being sold at this point?

What's the latest on the 77mm IR-CUT filter for the EX1?

Is there a good solution that does not have the green shift issue at wide?

Tom- Literally 15 seconds with the wanky color adjusting tools in "Preview" on the web create a perfect match on those 2 stills.

Just watched a BBC TV show (Strictly come dancing) and noticed that the Judges on the show all appeared to be wearing very brown looking suits. Looks like IR to me and this is a top end HD studio shoot.

Are referring to color correction for the green tint or for the reddish / brown hue due to IR contamination? As far as I know IR contamination could not be colour corrected.

I just have a slim 486 filter on my EX1 lens all the time, and problem solved.

If you want a cheaper version with front groove, here it is. But I'm unsure if it fits under the hood of the stock lens shade.

I have a set of high power IR illuminators that I have just purchased for an up coming shoot that will be in total darkness. We are going to be using Sony HC1's for the shoot with the nightshot mode. You can just about see a very faint glow from the lamps with the naked eye. Point the lamps at any subject and then shoot it with an EX and you get nothing at all. Point the EX at the lamps and you see just the very slightest hint of a glow. This suggest some very heavy duty IR filtering does exist on the EX.

Alister, despite whatever IR filtering already built-in, EX1 is famous for color shift (usually black objects becoming brown) due to IR contamination.

It's very ugly, and I've observed it under both natural sunlight and Fluorescent light sources like Kinoflos.

Solution is to filter out IR properly, and 486 filter (see my post above) helps 100%.

I'm not saying that it doesn't exist, just that are we sure it really is simply down to poor IR filtration? I have cameras that clearly don't have good IR filtration, point a remote control at them and you can see the IR led flashing away, yet they do not exhibit the colour cast that the EX can. There shouldn't be any IR at all form Kino Flo's and very little from Sunlight compared to the ambient visible light levels. I've seen this brown hue now on many modern HD cameras and it is almost always associated with man made fabrics, normally under tungsten light. I'm not convinced it is just IR that's causing it, you can get some strange effects a certain frequencies and reflected light.

Do you have the green shift issue when at the wide end of your lens?

Can anyone definitively say that this "non-slim" version will fit with the stock lens shade? I seem to remember that someone said it would, but barely.

I own the 486 Slim and it fits with lots of room behind my EX3 hood. Perhaps, I got lucky but so far I have NOT seen any green cast in my shoots. Sorry, I just re-read your request. I cannot speak for the "non-slim" version.

I have the 486 non-slim version and it fits perfectly under the stock lens shade on the EX1.

I also have a Tiffen pro-mist 1/2 and it doesn't fit under the stock lens shade!

" I've seen this brown hue now on many modern HD cameras and it is almost always associated with man made fabrics, normally under tungsten light. I'm not convinced it is just IR that's causing it, you can get some strange effects a certain frequencies and reflected light.
__________________
Alister Chapman"

I've been getting this consistently (black turning to brown) shooting a collection of tin toys against black fabric with tungsten light. Crushing the blacks makes it go away. Haven't seen it in anything else.

Thanks, Robert. It will be great to rid my shots of burgundy-blacks, and you just save me $57.

It seems that Rosco has launched a new filter at NAB:

ProVideo Coalition.com: Stunning Good Looks by Art Adams | Cinematography

Eager to see Adam's test on this one......

I bumped into Ryan Avery at the Schneider stand at NAB. They have a new IR cut filter for the EX's. Didn't get too many details from Ryan but this filter is a combination polarizer and IR cut filter which I'm told will prevent the green vignetting. Only saw it in a 4x5.65 size and I didn't get the part number.

I want a solution for tungstun first, that's where it is a big issue for me.

If they've got a solution, why are they bundling it with a polarizer? That's a special effects filter, not one you can use all the time.

I should probably leave that up to Ryan to answer but I got the impression that by polarizing the light before it enters the dichroic filter the green vignetting was avoided.

This is my impression as well. However, in low-light situation, filtering the (little) available light further is not what we want...

Oh well, I guess we need to compromise - just as Sony did, for some reason not applying a proper long red filtration to the EX series cameras in the fist place.

From my experience so far, the problem is much ore amplified and noticeable in an indoor setting under tungsten light rather than in sunlight. So basically the urgent need is for a filter that does not cut any light but restores the blacks.