Jay, to be fair, Schneider did solve the IR contamination problem with their Tru-Cut 750 but for the RED camera only as it was found out that this filter does not work for the EX cameras. Rosco are saying that their filter works well with no green cast but I suspect that they have been tested for the RED camera as well.

The problem as I see it is that the EX series are so sensitive to IR that an aggressive filter like the 486 will cause a green tint and anything less in IR blocking power will lead to no effect just like the Tru-Cut 750.

I fear that this problem will never be solved for the EX......

Tiffen 77mm Hot Mirror test
 

I found a used Tiffen 77mm Hot Mirror ($50) at B & H. I shot with Vortex PP, fairly low ambient tungsten light, 2.8 iris, and found 8 black materials to test. I found the filter cuts the 'brown/magenta' shift a little - but not a lot (see photo). I did not see any 'green cast' on wide or any other focal legnth.

The neoprene wet suit, cotton shirt, and black fleece materials had the hardest time with the CMOS IR.

The camera makes awesome pictures for what it is. For me I don't see an everyday need for an IR cut, so I am keeping this filter to use if it ever becomes an issue. It appears to offer enough of a 'acceptable' correction for any situation I have come across so far. For any critical 'black has to be black' shoots I will probably rent a 486 or use another camera.

Hopefully, a better solution will come.

(Couldn't get an image bigger that 500k to upload on this site)

EX Cameras and IR
 

Let me set the record straight as it stands right now:

At the beginning of this whole EX and IR light contamination issue we here at Schneider spent some time considering all the options. We made the recommendation of the 486 based on the testing data that we had from real end users and information of the sensor as well as our filter.

We hence discovered some users found that it caused a blue to green cast in their images. I concluded that in certain situations this did not work thus I recommended the True-Cut 750. The True-Cut 750 was shown to work in some but not all situations on the Sony EX cameras only. The RED camera continues to work fine and IR problems are greatly diminished with the True-Cut 750.

So we have discovered that the IR contamination issue with the Sony EX series cameras is dodgy at best and the IR cut required is all over the map given the IR content of the light and the material you are shooting. I have satisfied users on both sides of the fence that use both the True-Cut 750 and the 486 for their EX cameras. Any statements made either way by myself on the use of IR filters were based on the latest info at the time of the post. The IR contamination issue is a developing and quite frankly "moving target" given the camera that is being used and the other variables listed before.

We continue to work on this problem to find a one size fits all solution. Currently, the 486 has the least incidence of issues with end users and continues to be the most popular choice for diminishing the IR issue. But it is not perfect for this particular camera and some users have experienced the blue to green cast whereas others have had no issue.

The best suggestion is to use the 486 for your Sony EX camera if you are desperate for a solution now but realize that there are some risks in using this filter. I am hopeful that we will devise a "perfect" solution but much more testing is required.

I must make it abundently clear that the True-Cut IR 750 is the best solution for the RED camera and any RED user should buy that filter for their camera if using heavy ND filters. The application of the True-Cut IR 750 is only less than ideal for Sony EX users (but does work in some shooting conditions!).

Your patience is appreciated and we are likely to have a workable solution soon.

Ryan Avery
Schneider Optics

Thanks Ryan ...
 

I know that you are working on a solution and shall wait !

Kevin,

Thanks for posting those pics. Doesn't seem to do much though. I'm figuring I may get something like a 486 eventually. If it works OK except on wide lenses then it would at least be valuable in the event of an interview with a big exec wearing a black jacket. That's a place I could imagine the client getting touchy. No need for a wide there.

Lenny

Thank you, Ryan, for that clarification! Much appreciated.

I'm just curious, is Sony providing any input into your efforts to resolve this issue?

A promising response to my inquiry about an IR filter 'shootout' from Art Adams at the ProVideo Coalition. He has posted two very informative and comprehensive filter shootouts with a RED and most recently a Sony F35. I asked if there would be an EX filter shootout:

"I’m working on that right now. I’m hoping to have it up in the next week. I’ve got one more set of filters to test, and so far the results have been very surprising--in a good way!"

Posted by Art Adams on 02/20 at 11:01 AM

Stay tuned! Maybe some good news on the horizon.....

If you can get someone at Sony to return our calls, I would appreciate it.

Ouch! That's not very encouraging! :(

Ryan, let me see what I can do.

;o)

Just did a video for our local symphony of which I have tried the tru-cut 750, B & W hot mirror and finally the 486 on my ex1. The 486 is the only filter that made the tuxes black, both of the others had little or no effect. I did not notice any green fringing with the 486. So unfortunately I had to spend 600+ dollars to find a solution.

Thanks for posting the your findings, John. Can you tell us if you're using any of the picture profiles from the forum (like Bill R's)?

The green vignetting usually happens when wide angle is used. If you zoom in somewhat as your concert shot is, you shouldn't get the green fringe. If you were setup on stage, you probably would have gotten fringing.

hi, does anyone have a link to purchase the 486 in the UK?

I bought mine thru Amazon.co.uk They do not actually sell it themselves but it is sold via their website thru someone else on their behalf. They do not have the slim fit but the hood still fits perfectly on the non-slim filter.

Here is the link: http://www.amazon.co.uk/B-W-77mm-UV-...5479909&sr=8-1

486 ?
 

Hey guys,

Been watching this thread for awhile... I have the b+w 77mm uv filter (#010).

the one I have is for uv only but will not correct for the infrared issue inherent in cameras with digital sensors... correct? Will the b+w 77mm 486 uv/ir filter correct for both uv and infrared issue on my ex3? And can I also leave it on my camera at all times for lens protection?... or will it create other problems i.e. like shooting at night.

thanks

Greg

I intended to replace my B+W UV filter which was acting as a lens protector with this 486. However considering that this 486 produces this ugly green vignetting at wide angle, I decided to put it on only when I encounter the IR contamination problem, for the rest of the time I will keep on the B+W UV filter.

Greg,

The UV does not correct for IR contamination. The UV/IR does both however I do not recommend it for full time use given its limitations at full wide angle. Unfortunately you need both but don't use them at the same time.

Ryan Avery
Schneider Optics

Thanks Brian :)

Filter for IR contamination
 

I've been watching this thread with great interest for some time now and I appreciate the research conducted by all of you. I particularly appreciate Ryan and Schneider Optics for going way out of their way to help solve an issue that Sony should have stepped up to the plate for, long ago. Tiffen used to care like that, but it's not the same over there any more. Unless, maybe, if you're Spielberg.

Although I love my EX1 and EX3 I have spent many hours color correcting blacks clothing and fortunately, my clients have not yet complained. I have found that the "color match" plug-in in the Boris CC filters can usually return black clothing from red to very close to original black, (without killing everything else) by simply adjusting the "Red - shadow source" to a higher number. This combined with your normal color correction will usually save the day, but not always. Unfortunately, some fabrics just react so strongly to infrared light that the jacket may not match the pants of the same suit.

I too tried several filters to right this problem at significant cost, but to be honest, the camera has worked so well and looked so good in most other situations that I can't complain. It has helped us go places we couldn't previously afford to go in this business.

Ok That's my two cents.

Chuck,

I do appreciate what ryan has been doing a great deal, but don't count Tiffen out.
I recently talked to them at a trade fair in San Francisco and they brought a whole group of new "Hot mirror" and "Hot Mirror IR ND" filters designed specifically for the Red and other video cameras. They have also been doing their homework on this one though no one ahs shown our little camera the attention that Ryan so generously has.

As for our beloved camera manufacturer....

Lenny Levy

This is what makes this forum great...
 

As an owner of an EX-3, I have noticed reddish blacks and not loved it, but being very happy with the camera otherwise, didn't ruminate too much over the problem. This thread has been extremely enlightening about the true import of the problem and about the range of present solutions and their limitations.

It has also stimulated the manufacturers (some anyway) to greater efforts and made us endusers aware of the possibility of more optimal filters in the pipeline.

Having read all the posts, I've elected not to jump the gun and buy the 486 or anything else, but to patiently wait for Schneider, Tiffen and Rosco to sort things out and give we thousands of EX owners what we need to get great results with our cameras under almost all conditions.

Thank you Chris Hurd for such a great forum, and congrats on your role in getting the ball rolling on the SI camera!

Tip McPartland

Here is a stage shot at full wide, to me an acceptable image in comparison to burgundy tuxes or brown and some black.

720/60p BBC Video setting stepped down 1/2 stop. 3200k preset for color temp. Still quite haven't figured out the best way to deal with downlighting and bald heads...

which one did u order?

What's recommended though for indoor applications that don't need ND?

Well, I had originally ordered a .9 IRND. But when I called to add some additional items to my order, I found out that Tiffen does not make that filter in a 4x4, and they would have to cut it custom which would take up to two months. (the original order was accidentally made as an IRND WITH Hot Mirror, which is apparently available)
So I canceled the order, and am in limbo at the moment. I really didn't want to wait two months for the filter.....

Another way: reduce IR
 

Regarding shooting indoors without ND filters, I would think that another approach would be to use lights that have a reduced IR signature like solar spectrum Alzo Digital phony HMIs (actually HID) lights that run much cooler, their "higher color temperature" notwithstanding. Also solar spectrum fluorescent or better yet LED instruments would give you less IR with which to cope.

This might be one reason that Sony is selling LED on-camera lights.

Tip McPartland

Dare I say this?

I think Adam's methodology is possibly flawed. Look at his first shot, no ND filter and no IR contamination. The problem he's trying to fix is different to the one we're trying to fix.
Also his test fabric is synthetic, we know that certain fabrics don't show up the problem.

By adding ND filters he's induced a different kind of problem where the sensor and it's filters are swamped by IR as the external ND filter doesn't cut IR. We see IR problems in all of the frame including the chart. This is not the same problem that we're having. Sure it could be a problem as well if adding external NDs.

This is exactly what I think.

1. I don't have any serious problems in sunlight, only tungsten which implies lowlight - thus using ND is out of question

2. I never have everything contaminated, just some specific, black or dark blue materials

3. I have found that instead of using 3200K WB (typical for tungsten), it's enough to dial WB down to some 2800-3000K and the problem is gone, with only a little overall impact on the remaining colours - usually fixable in post.

4. Re: using LED, or another cold light, instead of tungsten: the rendition of people's faces it creates is a much more serious problem that the tungsten IR contamination of their tuxedos!

I'd have to disagree about 4). We use nothing but daylight balanced fluro, LED or HMI lights and everyone of our users are very happy over how good color rendition is. That's on top of the reduced heat and power requirements. So happy in fact we've just doubled the number of such lights we have on offer, despite the state of the economy we cannot meet demand at times. These lights have been used with just about every video camera out there and to shoot 35mm, 16mm and stills.

I'd also point out that I haven't seen a tungsten lamp in a local television studio down here in a long time. I am of course talking about light sources designed for television and film. Certainly there's no shortage of cheap "daylight" lights with poor CRI that can indeed give bad skin tone.

Bob,

I only meant a situation where an on-camera fill light somebody mentioned above is LED, and the rest of lighting is a typical, home tungsten - this is when balancing the WB is extremely difficult, and skin suffers most (or you get everything else reddish if you set your WB high).

For a fully controlled lighting environment, you're right of course.

Fair enough, You know I could tell you the solution to that problem but I know it's probably our of your price range.

I just took the 486 off my camera and tried shooting various black fabrics in full sun. No sign of IR problems that I could see. From all the screenshots that I've seen of IR problems under sunlight they're all taken when the sun is very low in the sky. I suspect at those times of day the shorter wavelengths are more filtered by the atmosphere.

Based on Art Adams' article, it seems that the problem isn't IR. Otherwise the filters designed to cut wavelengths longer than 700 nanometers would have the desired effect. They didn't.

Instead, he seems to have discovered that a filter which attenuates wavelengths longer than 680 nanometers appears to work well.

B&H does have a Tiffen filter that might work. But it's still an ND filter that cuts a full stop: Tiffen | Neutral Density 0.3 (ND) Infrared Glass | 45650IRND3

I can test to see if an LED light helps reduce the problem. I have a set of Cool Lights and the spectral distribution of the light has a significant dropoff after 610 nanometers. Maybe I can do a comparison of a few black objects shot under full CTB tungsten and the daylight LED.

I posted charts comparing the Cool Lights LED to full daylight here:
http://www.dvinfo.net/conf/photon-ma...ml#post1018808

I think I can confirm that the issue is not caused by typical IR wavelengths. I pointed a remote control at my EX1 and with the 486 filter on saw nothing. With the 486 off I could just see the LED blink but it was quite faint. My other camera with the internal IR cut filter out of the path (Nighshoot) the IR LED in the remote lights up very brightly. Also I noted that the EX1 showed the IR LED as white so it's getting in through all the RGB filters on the photodetectors roughly the same amount.
I don't know the wavelength of these IR LEDs, they typically seem to be around 800nm to 900nm.
So I think what Adam Wilt has confirmed is what Ryan Avery said some time ago. The red filters on the sensor are still letting wavelengths just below visible red through. That might have a deliberate move by Sony to get more sensitivity out of the sensor. Cutting it right off at the edge of the visible spectrum many have also attenuated some of the visible spectrum as well.

So really I think we're back to square one. We need a filter with a very sharp cutoff at 680nm out to at least 720nm. Any wavelength longer than that and the camera is already filtering that out.
Now the Tiffen filter according to Adam is using a complimentary color filter and it has to match the ND filter, that's all good but doesn't give us a filter we can use to cure the problem with the camera at all.
I'd also suggest that the 486 is not a typical "hot glass" filter. We have a ND 1.5 and ND 1.8 hot glass filter and the coating on the front looks just like a mirror, I could use it to check my makeup.

To put it simply , Adam has confirmed the nature of the problem, we still do not have a solution. Shooting stage shows with a ND1 filter on the camera even if it cured the problem is not an option, period.

This twist in this issue is very interesting but confusing as well. I cannot understand why in the test only ND IR cut filters were used. The problem is more accentuated under halogen lights than when filming in broad daylight. So any loss of light due to ND filter is unacceptable especially when shooting under available light (and not controlled lighting).

Can someone explain whether these Tiffen ND IR filters can be produced without the ND component in them - just IR cut only? Or is it not possible to have an IR cut filter which works well without some ND inside it? The 486 does not have any ND but then again it does not work well.

Piotr I have to disagree also with you on point No.4. I used to say the same thing like you said but after receiving my new Zylight 90 just yesterday I will not use any halogen on-board light again. The Zylight 90 is the LED lamp to use for ENG. It's true that it is very expensive (it took me a year to decide to buy it) but the ability to switch the colour temp at the touch of a button without using any light reducing coloured gels in front of the led's is fantastic. I haven't used it in an assignment but from the tests I did yesterday it's absolutely amazing! I bought it specifically to eliminate the halogen light on board of the EX3 which was causing too much contamination.

I couldn't agree more with this last statement, Bob (with a little correction - we're not talking Adam Wilt's article here, but that of Art Adams :)).

However - after having tried the screw-on 486 and 489 - I'm now having a 4x5.65" filter from a manufacturer whose name I'd prefer not to reveal at the moment. I have just completed a quick and dirty series of tests, and here are my results...

1. YES, even in daylight at 5600K, the blacks CAN be a bit contaminated - just compare the first pair of my grabs (upper left - no filter, upper right - with filter X)

2. In tungsten light at preset 3200K, EVERYTHING is too red - but still the middle right picture (with filter X 3200K) shows some improvement over no filter (middle left) (BTW, sorry I forgot to re-focus on the main subject - the bag - after I had to open up the iris due to lower light)

3. As I said before, dialing WB down to 2700K (to balance at the white card) allows to minimize the red contamination (bottom left - no filter), and the filter I tested makes the black ALMOST completely black (bottom right).

Conclusions:

1) 3200K is commonly used as the right preset for tungsten lighting; looking at the grabs, it's obviously too hot - always do white balancing before actual shooting! It seems to have much stronger influence on the alleged "IR problem", than using a Hot Mirror filter...

2) The B+W 486 filter can get rid of ALL contamination (see my comparison grabs in another thread); should it not produce the ugly, greenish vignette at wide angles, it would be the best solution for the EX cameras... Just what kind of filter is it ?!!

Comments welcome!

Sure - if you can change the light temperature, it's great (and expensive:))...

I used to have the Sony on-camera LED light (no 3200 filter - just 5600K; 4000K with dimmer on), and in situations I mentioned above (where the surroundings were more towards 2700 - 3000K), faces did look ugly.

Of course, I might have used some amber gelling, but then the lumen/watt ratio would drop dramatically down to a regular, halogen lamp that I'm using now. Much smaller and versatile!

Piotr, whenever I've encountered IR contamination (or whatever it is...), under halogen lights, I've always manually white balanced on a white paper and got a reading of about 2600-2700K. I never use preset and yet I've witnessed some horrible black-turned-brown fabrics. Seeing your test, I'm now wondering whether I should use the warm cards at all in such situation. I was intending to start white balancing always with the 1/4 Blue to warm a bit the picture but will need to do some tests as the warming effect might enhance the "contamination".

I'm also wondering why some people have stated that they are not seeing the green tint with the 486. Could it be some manufacturing inaccuracies that are producing the ideal filter unintentionally and unknowingly?

I think I found a temporary solution to this IR contamination problem. As I had indicated before I tend to film a lot under available light (without any fill in light) which on most time is predominantly halogen. This was obviously giving me loads of problems with black material.

I have just done a very quick test - I filmed a black t-shirt under available halogen light. This as expected turned to a brownish tint. I then switched on the newly bought Zylight 90 and since this is LED light the black t-shirt was restored immediately back to black! Even when I had dimmed the light to almost minimum, as long as a very small quantity of LED type of light fell on the black fabric, the problem disappeared (without the use of any filter). Please note that the Zylight was switched on the 3200K setting so as not to disrupt the white balance that had been set to the prevailing halogen light.

This means that unfortunately I have to change my style of filming and start using some dimmed fill-in LED light whenever there is halogen light as the main source of lighting. As I said this was a very quick test. I have yet to test it out in a proper shoot - but I'm expecting the same type of results that I had obtained today.