Schneider Optics True-Cut 77mm waste of time
 

I sent back my B+W 486 to B&H and ordered a Schneider True-Cut 750 77mm from Schneider Optics directly on the direct advice given on these forums by Ryan Avery. It does not work, at least in tungsten only light. Examples:

With no filter, halogen lighting, white balanced on white ceiling provide the light diffusion for the up facing lamp
http://www.atsi.ca/ex3/filter_off.jpg

Same setup with the filter attached
http://www.atsi.ca/ex3/filter_on.jpg

The 486 from B+W worked and made the bag and towel as black as the other items in the shot that show black no matter what. The problem with the 486 was some green vignetting which I wanted to avoid having to correct.

If anyone is contemplating getting the True-Cut, hold off buying it until this is resolved. As it stands, it appears to do nothing in the lighting conditions described. It might have an effect with different light sources although I doubt it.

Les, I e-mailed Schneider Optics directly, requesting price and delivery for the new 77mm True-Cut filter. I also asked if the their new True-Cut filter has resolved/corrected the "green cast" inherent in the 486 filter. A week now and no reply. So it is wait and see if they will deliver the goods.

I saw no bad fringing in my short testing, but it does not cut the IR contamination at all as far as I can see. I would hold off..... Too bad I don't have the 486 still to compare.

Les, when one says that a green cast (vignetting) appears with the 486, does it refer only to when one attaches a wide angle attachment or does it also appears on the EX1/3 stock lens when the lens is at its maximum wide angle?

And how bad is bad? Do you happen to have a screen shot showing this green cast?

According to your posted pics the True Cut is just a very expensive, useless piece of lens protector!!!!

Thanks

Brian

The 486 caused the green vignetting on my camera with the stock lens at the wide end of the range. Fixing or at least partially correcting for the green cast at the edges is possible but correcting for the black IR contamination problem is not without some pretty destructive effects on the image

Sorry I didn't keep any shots.

It appears so for me at this point :(

Les,

That's a real pretty bag you have there!

I can't believe that the filter made no difference - I was shocked.

Les,

I can honestly say that we have sold many of these with several extremely satisfied customers. Yours is the first problem I have seen with this so one of two things has happened. Either you received a filter that is somehow not to spec or you have used it improperly. It appears from your tests that you did this under a controlled environment but I cannot say for sure until I test your particular filter myself.

The True-Cut IR 750 requires that it is the first filter the light hits. This because it reflects the IR light. If there is another filter in front of it, it will not work. Also if there is another UV filter in the series it will diminish the effects.

Please see our other extensive threads as to why the 486 is not the best solution for video cameras. It works great on still cameras. The 486 was designed to cut off around 680nm which creates a green cast on the images when a wider angle lens is used such as the lens on the EX1/EX3. The True-Cut IR 750 does not have this problem because it cuts off at 750nm. Because of the higher cut point, the filter helps avoid the near IR spectrum that contaminates the image.

To be clear, it appears that you have a defective filter and I would send it back and we will replace with a new filter. I would encourage anyone out there who owns this filter and is satisfied to post your results. I could post my own images but I think a customer review would do better for us all.

Schneider Optics has no interest in distributing a filter that does not work for the intended purpose and these filters were highly tested before bringing them to market. We offer the finest quality products for professional use. Please contact me via email for any other details.

Ryan Avery
Schneider Optics

Ryan:

I want you to understand that I was making no accusations. I understand that errors in production can occur, as well as variance in customer use and equipment. I can assure you that the filter was installed on the front of the stock lens. There is no other non-stock Sony optical element in the optical path.

As I said, the 486 worked in that it removed the brown and purple tinting of black items but caused the green edge problem you refer to. That is why I returned it.

I still need to correct for this problem so I hope a replacement will work. I have already contacted the Van Nuys location where I purchased this from and have an RMA. Hopefully I can get a working replacement fairly quickly.

I'm having trouble finding a 77mm version of the True-Cut 750 on the Schneider site.

I'm interested in the 77mm True-Cut IR 750.
Les, let us know how it works out for you.

Ryan, as always, thanks for the info.

That is because it just came into production. Any filters that Ryan refers to are not the 77mm size I believe. I called in my order to Schneider Optics and waited till they got one in stock.

That makes me feel a little better. Not much, but a little.

I've been working with the IR-750 for a couple of months now in preparation for an article on EX-3 as well as for presentation on EX-3 at an upcoming event in LA.

I will be putting up some results but what I can say at this point is that I strongly recommend it for EX shooters.

So where does one go to buy one of these filters?

I would very much like to see your test results as soon as possible. It is obvious that with my camera it does not work. Based on a conversation I have had with the optics engineer responsible for this filter at Schneider Optics, it is unlikely that this filter will fix my problem and that the one I have now is not defective. It could still be defective but our assessment of it is that it isn't defective and just is not suited to the issue I am seeing.

In which case...
 

So have you ordered another 750nm replacement or have you selected another model? really curious to see results since I also need one in a hurry and can need to make the right choice.

Jus.

Sorry Justin, I don't have any answers for you. I am sending mine back for a refund and living with the problem until something is worked out better for our cameras. I might get another 486 and use it when appropriate and correct its flaws to the best they can be corrected or avoid the focal range where it is a problem.

I believe ...
 

I think you have to email Schneider Optics directly and place an order.

OK, I'm new to this but what does this filter do [or not] that I'm supposed to be able to see between these two images?

I do not understand this. Ned owns the same filter, right?
Why are we getting different info on this filter?

Here is a link to a page where they did a short test with the 486.
ProVideo Coalition.com: Camera Log by Adam Wilt | Founder | Pro Cameras, HDV Camera, HD Camera, Sony, Panasonic, JVC, RED, Video Camera Reviews
As you can see it makes the shirt black, but it also has the problem of causing a green vignetting problem. The True-cut does not have this desired effect on blacks as was hoped.

Why do Adam's test images lack the green edges that the 486 is alleged to give?

Ask him? Variances in production tolerances?

That stinks!

Are you referring to the filter or your camera?

Maybe your camera's sensors may have a problem. Wouldn't Sony be liable for getting that repaired?

The answer is simple, and many times mentioned in this forum (by the 486 users, and by Ryan Avery of Schneider): the green cast is only occurring with some specific angle of light incidence, usually at the picture extremities at full wide zoom ranges.

Common problem.
 

Adam Wilt's research would seem to suggest that this is not an uncommon problem with digital video sensors. It's still a pain the the ass though.

Jus.

IR is not just a problem of CMOS cameras.

I shot Steve Job's keynote at MWSF last January for a publication for which I write.

Shot with my HVX200.

The images of Steve's brown turtleneck were great.

This is with a CCD camera.

I'm about to reach the point where I would simply just keep in IR750 on the lens at all times and ditch the traditional UV.

Sorry, I didn't mean to appear flippant. Production variances of the the camera and /or the filter could interact differently. The lenses won't be perfect replicas of each other even if they are within tolerances set by engineering and QC. Sensors from the centre of a wafer have very different characteristics than those from the edges. Perhaps I got one of the ones that exceeded IR sensitivity than most others. Filters are made within tolerances too and who knows what is an acceptable variance for them? I have a sample of one of each so I cannot say why my camera and filter exhibited the problem and the one tested elsewhere apparently didn't.

I actually am considering getting Sony to look at my camera because the problems with blacks I am experiencing more often are not subtle. I suspect that perhaps my camera is flawed or perhaps more correctly is on one end of the range of IR sensitivity. It is definitely worth looking into and I will when I can at the earliest.

Having said all that, I have the confirming discussion from the Schneider Optics engineer who agrees that it appears that both filter designs are not suited, or more likely more reliably suited, to the needs of the EX series cameras.

If someone has images showing the True-cut fixing the kind of problem I have shown with my images on an EX3, or of a 486 on an EX3 that works and also doesn't cause green vignetting, I am sure everyone else would love to see them so we can narrow down causes and solutions.

I've done a few preliminary tests of my own. Using my EX3, I see the problem only part of the time. Not all black on all fabrics come out reddish.

This being the case, is it a fabric issue, a dye issue, or is it a combination of the two?

I remember back in the day when I was a commercial photographer, we had issues getting certain colored fabrics in our photographs rendered accurately. Eastman Kodak developed a film especially designed to illuminate the problem. It's been so long ago, I can't remember the name of the film stock. In any case, it was a welcomed addition to the arsenal.

It's dejavu all over again.

I believe it is a dye issue, or the type of dye that is used on certain fabrics. So I guess it could be a fabric issue indirectly. I see the same result. Not all black fabrics have the problem but many do.

I have been hoping that those who claim that they have the problem solved with the True-Cut filter would post images of their success. We really need to figure out the best solution for all EX owners.

Indeed! I'm right there with you, Les.

Not Available Yet
 

Schneider has not responded to my e-mail request to order the 77mm True-Cut filter. There is no price or delivery information at this time. I'm pretty sure that Schneider is aware of the need and will let us know when they are ready to deliver.

You're SO right, Jay. My background is also in Commercial Photography and I remember that certain fabrics would "flouresce" (sp?) due to brighteners added to the fabric dyes. I think it was one of the Ektachromes that had the properties you mentioned but I can't remember the emulsion numbers anymore. That was many, many sheets of 4x5 ago! I also remember that certain "crossover" colors would cause problems as well. For instance, getting certain shades of teal would be problematic. The transition between blue and green could be a nightmare. The first test shots I did with my EX1 was under tungsten light of a guy talking. He was wearing a black baseball cap and it photographed as VERY brown in color. I'm following this thread with great interest as well.

This is often stated, so must be so. But why is it so? If the filter is placed downstream of other optical elements that will reflect IR reflected by the filter, how is that second reflection altered in such a way that it gets passed by the IR cut filter? If the filter reflects 100% of IR in the specified bandwidth, then any reflected IR in the bandwidth will get reflected again (and not passed). If 90% gets reflected, then on the second go 90% of 10% gets bounced back again, and so on. How do other filters change the bandwidth of the IR component prior to meeting the IR cut filter, to make it less effective? True a filter does not have a square cut-off characteristic, but how does that affect the argument?

Serena

The filter works by using interference principles of multilayers to reflect the desired wavelengths instead of letting them pass on. The layers are spaced properly for the wavelengths desired. Light entering the filter straight in are properly affected. Light entering from an angle see the spacing of the layers differently because of the angle and therefore do no interfere properly.

When the filter is the first optical element the reflected light disappears harmlessly into never never land. If the filter is behind other optical elements it is possible for those elements to scatter and reflect the light back towards the filter in such a way that they enter the filter at an angle and get through. Lens designs this kind of complexity have to be carefully designed to prevent such backscattering in the first place and adding a mirror arbitrarily in optical path is almost a certain formula for problems. These problems could be flare, ghosting, multiple hot spots, etc. That is not to say that it isn't possible for something added in the optical path to work but the chances are it won't fix the IR problem without causing another or even worse multiple problems.

IR filter ...
 

This effectively means that one would have to get 2 IR filters if working with a mattebox and other filters behind that and one to go directly on the lens when using the fujinon lens shooting with the EX3! I wonder if Schneider optics would bundle both filters for a reduced price? The 4X5.5 is $400 and the 77 mm is around $300. That's pretty pricey for just this filter!!!

anyone tried using a tungsten to daylight colour correction filter and then shooting with a daylight white balance. This would allow the use of a stronger red reduction via the filter although it would push up the cameras red sensitivity.

Barry and all,

We taken considerations regarding the EX-3 and the True-Cut IR 750 into account. Our engineers have worked to deduce the problem Les experienced. We value our users feedback and are always looking for ways to exceed your expectations with regard to quality and performance for which we are known. If you already own a True-Cut IR 750 and have not had any problems, then you are ok.

You can buy this filter at any of our authorized DV Info sponsors.

Reference the description and part number:

77mm True-Cut IR 750
68-121077
List Price: $250.00

Ryan Avery
Schneider Optics

We have developed a 1/2 strength blue color correction filter. It seems to work well with the RED camera for which we developed it. Our Sapphire Blue filter was being used on productions but it was slightly too strong so we reformulated it with some changes particular to this application.

Ryan Avery
Schneider Optics

Ryan, how do you feel the 489 works for IR cut?