Tiffen GlimmerGlass

[Rafael Lopes]

Hi,

When taking a look at some footage shot with the G35 I notice that not only does it have a very nice sharp DOF, but it also produces a very beautiful subtle "glow" that cuts the video edge and makes it look very film like. I was wondering if there's any filter out there that will produce this effect. Sometime ago I saw a still photo that used a Tiffen GlimmerGlass (I cannot recall the intensity) and it had a similar effect. Did anyone have such an experience with any filter out there?

P.S - The thing with diffusion filters is that if it's not subtle enough you'll end up with footage that looks like a bad porn

[Marcus Marchesseault]

Have you tried any software filters? I think that physical filters might be best to eliminate unwanted light and effects might be best in post since they can be adjusted or eliminated at will.

I am using polarizer and ND filters and will probably leave the effects for later.

[Ben Winter]

I agree with Marcus, however I also have a 3x3" Tiffen Low Contrast filter of the highest power (five) and it not only knocks down contrast for better color correction and higher latitude, it produces as a side effect this subtle diffusion you speak of. I would highly recommend it.

Rendering diffusion/glow effects in post is particularly time-consuming compared to other color correction effects, probably the most power-intensive of them all. People speak freely of adding effects in post, but quite frankly it can come to be a very time-consuming and frustrating process, I know I've wished in the past that I had just slapped a filter in front of the lens when I shot the darn thing.

[Marcus Marchesseault]

I also agree with Ben that some things are easier and faster with a filter. If you know you won't want to change things later, a filter isn't a bad idea.

Increased exposure latitude can't be achieved once an image is recorded (color correction helps, but it doesn't actually increase latitude), so I have thought of using a low-contrast filter. Ben, I've been thinking that a low-contrast filter might help simulate the effect that the ground glass in a 35mm adapter has on the image. Specifically, I would like to help match the greater latitude and slight softness for times I can't use the adapter. Do you really think that strong #5 low-contrast is ideal? It's not overpowering? Do you need to do anything in post to keep it from looking "milky"?

It's these kind of things that can't be done in post that I think is perfect for filters and I think people need to learn how to use them. I have my Cokin filter holders permanently attached.

[Charles Papert]

I haven't used them in years, but the Ultracons were good friends to me when I was shooting Beta and Digibeta as they reduced contrast without the milkiness. Higher grades were more useful (I never used less than a 2)

[Marcus Marchesseault]

Why don't you use them anymore, Charles? You work with HD as well as film, right? Don't CCDs, whatever the resolution, have less latitude than film no matter how expensive the camera? Is there a drawback to using them that has made them less useful with HD?

Sorry for all the questions, but I don't want to spend a bunch of money on a filter that is questionable in it's usefulness. In theory, these filters seem like a great idea, but there must be a reason people don't use them all the time.

[Rafael Lopes]

Marcus, whenever I watched images from the G35 I always got the sensation that it increased the latitude a little bit (weather it it was real or apparent is beyond the point, since what you see is what counts) and it made the footage soft in just the perfect way (not too soft, not to harsh). This is one of the reason why I always found the G35 the best adapter around, because not only it accomplished it's original task of providing the sharpest DOF I've ever seen from 35mm adapters, but with the plus of providing more latitude (even if only apparent). What Jonathan Houser used to create this effect will remain a mystery...but not long ago I've seen footage from a homemade adapter that showed similar proprieties. The person who built it revealed he used some sort of nivea cream on the ground glass. The results are amazing (even though the images are milkier than the G35's). Now, if someone could at least come up with a filter that produced this effect it would be revolutionary. I tried tiffen ultracontrast#3 and I ended up selling it because it made the image simply too milky and absolutely killed all blacks (which in post brought me the problem of recovering the blacks). I've read about a relatively new filter from tiffen called HDTV, which is supposed to give you a bit more latitude and reduce the hard video edges. Sometime I've started a thread asking questions about this filter but nobody replied.

[Rafael Lopes]

For those of your interested: http://www.tiffen.com/userimages/HDTV_FX_FS.pdf

I would very much like to hear from people who used this filter. Footage would be appreciated.

[Marcus Marchesseault]

I also tried the Ultra Contrast 3 several years ago and did not like the results. I was not as experienced back then, so I may not have used it properly. To me, it just seemed to make things look "milky" so I never really used it.

The Tiffen HDTV/FX filter is a combination of Ultra Contrast and DiffusionFX, which sounds like it should have results similar to the Low Contrast filter that Ben mentioned.

[Ben Winter]

Here is a test of the Low Contrast filter power 5, with ND filter on a Sony FX1 equipped with the Brevis and Canon FD 55mm f1.2 at f5.6:

http://www.frozenphoenixproductions.com/tests/test1.mov

Provides some more detail in the shadows and I like it because it provides an image much more keen to color correcting as well as evens out the image for better latitude. At first I thought I was taking a resolution hit but then realized it just looked that way uncorrected because the contrast between edges was lessened.

[Marcus Marchesseault]

Thanks, Ben!

The proof of that filter's effectiveness is in that little patch of sky. It's obvious that the filter is bringing up the shadows, but until I looked at that piece of sky I thought that's all it might be doing. There is a tree branch that passes in front of the sky that smears without the filter. The sky also picks up more blue as it isn't overexposed. That's proof that the filter is compressing the latitude as it brings up the lows and decreases the highs.

I'm not sure if I like what it does to the mid-range, but I'm assuming that milkiness can be tamed with color correction. I don't ever plan to forego color correction, so it shouldn't be a problem.

Your test shot is particularly helpful to me as I also have the Brevis.

[John McManimie]

The Ultra Contrast really works very well to maximize dynamic range in the right situations.

I shot some waterfall footage in a heavily wooded area in which exposing properly for bright areas left dark areas black with no detail and exposing properly for shadows left bright areas overexposed.

With the Ultra Contrast 5 attached, I set (100) zebras to avoid overexposing. I also watched the histogram to avoid underexposing the shadows. With the filter attached, the histogram collapsed a bit so that it was clearly narrowing the contrast; everything moved closer to the dark end (left). However, the darkest end moved farther to the right. Stopping down the lens to keep from overexposing the bright areas still left the dark points farther from the left on the histogram (brighter) so that details were not lost. I could not get everything exposed properly without the filter.

The resulting footage came out very flat with low contrast. However, increasing brightness and contrast and adding an s-curve in post created a much better image than I could get without the filter.

[Ben Winter]

Originally Posted by Marcus Marchesseault

I'm not sure if I like what it does to the mid-range, but I'm assuming that milkiness can be tamed with color correction. I don't ever plan to forego color correction, so it shouldn't be a problem.

It took me a while to figure out, but the filter actually has a desaturation effect. A bump in saturation restores the mid-range very well.

[Marcus Marchesseault]

Wow, John, I would never have thought that that first image would result in that final product. Perhaps that's why I avoided using an ultracon filter in the past. I guess as long as the exposure is between the limits, there is information to work with. I think the moral of this story is that contrast filters are one part of the equation an should be finished with color correction.

That picture looks a whole lot like Hawaii! Was that shot here? That was a perfect example for me as I know exactly what locations like that look like in real life.

Ben, thanks for the tip about saturation. I might have accidentally stumbled upon that, but it's better to know about something and plan for the solution. Does in-camera saturation increase handle the problem or should it be done more selectively with color correction?

[Ben Winter]

Originally Posted by Marcus Marchesseault

Wow, John, I would never have thought that that first image would result in that final product. Perhaps that's why I avoided using an ultracon filter in the past. I guess as long as the exposure is between the limits, there is information to work with. I think the moral of this story is that contrast filters are one part of the equation an should be finished with color correction.

That picture looks a whole lot like Hawaii! Was that shot here? That was a perfect example for me as I know exactly what locations like that look like in real life.

Ben, thanks for the tip about saturation. I might have accidentally stumbled upon that, but it's better to know about something and plan for the solution. Does in-camera saturation increase handle the problem or should it be done more selectively with color correction?

In-camera seems to work fine to my eyes...I can never remember to change the preset back to normal when I take off the filter though :) I guess a little extra color doesn't hurt anyone...