Hello All

I'm using CS6 and I'm experiencing some issues when using Ultra Key. When I apply the Ultra Key Filter, my clips get real noisy and that affects my key.

I ran extensive tests and I came up with a strategy to eliminate as many variables as possible, so we can actually disregard trying to get a good key and just concentrate on the center mass of my subject... this way we don't have to get into a discussion on how to get a great key right now, because the problem is independent of the actual quality of the key.

As a disclaimer; I ran some Keys with solid graphics and was able to get a perfect key without noise... Because of this test my conclusion is that CS6 and Ultra Key together don't create noise.

So at first glance you might say "see, it is noise in your clips causing the problem"... But that's too simple

First let me say that I am using a GH4 with an Olympus 45mm F/1.8 lens and in spite of the rep for being noisy in low light at high ISOs, I am exposing correctly at ISO 200 and that produces a very clean image. In addition I'm shooting 4K 100mbp.

No sensor is noise free, but the GH4 is excellent, and even in low light it does a good job under 800 ISO (which I'm told is the native ISO).

I ran a test to make a point that we could explore in more detail. I also purposely underexposed the face so that it would have more noise for this test. The following clip shows the footage with and without the Ultra Key Filter applied.

The reason I included the clips of the eyes only is to make the point that regardless of any key specific issues, like even or proper exposure of the green screen, key settings, etc. that isn't relevant to the main problem... Adding the Ultra Key Filter amplifies and makes minor noise horrible.

Just look at the left eye. Without the key you can see minor noise that you might expect at 400% magnification and a underexposed subject.

As mentioned, at 100% magnification and at the proper viewing distance, you wouldn't think there was any noise at all... it's pretty clean.

But as soon as you add the Ultra Key, you can see noise everywhere and look closely at the left eye... with out the key there's some fine grain but negligible, but with the Key on, you can see some pretty disruptive noise.

The next shot series deals with fine hair against a green screen. Here I did not use an underlying graphic as it would distract from the test. Also, I did not try and get a "great key" because that also would obfuscate the test results, which don't rely on whether you achieve a good key or not. I just want you to see the noise before and after the Ultra Key Filter is applied.

What you will see is a clear amplification of noise any time the Ultra Key Filter is applied, even at center mass.

Here is the clip, and thanks in advance for any support you may lend!



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