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Old March 12th, 2008, 09:17 PM   #316
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That's an incredible degree of control. Are the Black Level, Gamma and Black Gamma settings continuously variable, like 0-255, or are they stepped levels like low, med, high?
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Old March 12th, 2008, 10:11 PM   #317
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Originally Posted by Randy Strome View Post
There are a lot of settings, and as always I claim no expertise. That said, my understanding is different than Piotr's.

I think visually, so in terms of curves:

Black level, (called just "Black" in PP) is your master black and sets only the black point. Middle Gray is shifted by "Gamma". "Black Gamma" Would be like setting a point on the lower region of the curve and adjusting from there.

I have been leaving the Gamma and Black Gamma settings alone, but I am sure I will start to meddle with those too.
You have been leaving the Gamma and Black Gamma alone???? You just said four posts back "I drop the black gamma until the histogram bottoms out" or word to this effect.

Either you or me is very confused - or maybe we can blame it on Bill?
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Old March 12th, 2008, 10:32 PM   #318
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Hi Michael,

Yes, I have been leaving Black Gamma and Gamma untouched, although I have not played with them yet. I was refering only to the Black level which in PP terminology is called simply "Black".

Did you mean where I said, "Then use the black level that best pulls the histogram (or waveform) to your floor. ?

I don't think I said that I adjust the other two, but if I did, ignore it :)

Black level (or black point-same thing) is different from black gamma.
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Old March 12th, 2008, 10:40 PM   #319
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Originally Posted by Tom Roper View Post
That's an incredible degree of control. Are the Black Level, Gamma and Black Gamma settings continuously variable, like 0-255, or are they stepped levels like low, med, high?

The 3 settings that you mentioned are -99 to +99 with every step available along the way. Other settings (and there are many) have different scales. Download the manual if you have a chance and perouse the PP section.

Have coffee ready. :)
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Old March 13th, 2008, 03:34 AM   #320
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Originally Posted by Randy Strome View Post
There are a lot of settings, and as always I claim no expertise. That said, my understanding is different than Piotr's.

I think visually, so in terms of curves:

Black level, (called just "Black" in PP) is your master black and sets only the black point. Middle Gray is shifted by "Gamma". "Black Gamma" Would be like setting a point on the lower region of the curve and adjusting from there..
Hmm... Sounds convincing, have to re-check. So are you saying that Black is what is often called Master pedestal?
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Old March 13th, 2008, 06:56 AM   #321
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Hmm... Sounds convincing, have to re-check. So are you saying that Black is what is often called Master pedestal?
Sounds very likely to me as the manual describes it as "Adjust the master black level". I'd have to check with a broadcast engineer but I suspect it's not called Master Pedestal as that term might be reserved for when the control is working on the analogue signal.
The typical use for this type of control is to increase the dynamic range available to the rest of the signal. It may be counterproductive using it to reduce noise in the blacks.
Black Gamma is probably what is know elsewhere as Black Stretch. Very handy when you have dark skinned people against night skies etc. If one can believe the manual negative values will reduce noise.

Low Key Sat sounds rather interesting as it would seem good for reducing chroma noise in the darker areas at the expense of the colours. Wish I knew about that one 10 days ago. A stage lit with only dim, deep blue was not a good combination for the EX1. Combine that with what was on the stage and it was a real stress test.

My problem with all these image adjustments is it's just not practical to change all these settings while shooting a live show. Big OB outfits have CCU operator(s) to twiddle all these things while the camera op worries about the basics of getting the shot.
My conclusion is the most important camera setting is the one between my ears, if I'm forever tweaking things it becomes very hard to build the experience to fly the camera under duress. Focus, iris and zoom is enough to worry about when also trying to frame the shot, switching PPs in the dark is not something I'd consider doing.
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Old March 13th, 2008, 10:15 AM   #322
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Hmm... Sounds convincing, have to re-check. So are you saying that Black is what is often called Master pedestal?
Apologies, I can't answer about master pedestal. I have never run across that term. "Black" is going to refer to the pre-placement of what will become the 0,0 point on your curve. Gamma adjusts middle gray. "Black Gamma" adjusts a point in between them. Where the black Gamma "point" is located on the curve, I do not know, but from watching it function live, I would guess it is very similar to creating a lower quartile adjustment handle.

That's all I've got :)

A side note: I believe that a bunch of us have been approaching this backwards. We got a new camera, were surprised a bit by the "Standard" (PP Off) setting, were a bit overwhelmed by all of the other options, and really wanted to be handed a "best setting". At least I did.

Now, I have gone back and looked at it more correctly. What is it that I am dissatisfied with about the shots that are coming out of the camera? Well, it is not the "color". I am really pleased with the Bill's tweaks in that area, and I am finding little or no need to adjust "color" in post. It is really just luminance curves that I have been struggling with in editing. I shoot watersports in Hawaii-often a surfer in black trunks in front of exploding whitewater in variable sunlit conditions. For me, I was exposing to just under the zebra 100, and allowing a bit of headroom for a mid shot exposure jump. With Bill's original setting of "Black" at -12 and often even the later adjustment to -8, I found that to place the "whites", I was driving blacks through the floor. Thus the shift to -6 and -4. Yesterday, I shot with -6 all day, and that may be my happy medium.

Here is an example that was shot at -6 staight out of camera:

http://www.dvinfo.net/gallery/files/5/0/9/2/3/ooc.jpg
http://www.dvinfo.net/gallery/files/5/0/9/2/3/wf.jpg

Last edited by Randy Strome; March 13th, 2008 at 10:58 AM.
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Old March 13th, 2008, 11:04 AM   #323
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Thanks Randy: Those numbers -4, -6 and -8 was what I was after.

I agree that never a need to color correct - just that luminance curve for with all these tweaks that are possible I still need pull that curve around in post more than I would have expected, but maybe when I get the master black right that will be less.

One thing I am also finding and I wonder if you all agree or not, is that whether I use CINE 1, 3 or 4 I can always get back to the same end result in post. So are we making too much of all this?

Mike
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Old March 13th, 2008, 11:19 AM   #324
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Originally Posted by Michael H. Stevens View Post
Thanks Randy: Those numbers -4, -6 and -8 was what I was after.

I agree that never a need to color correct - just that luminance curve for with all these tweaks that are possible I still need pull that curve around in post more than I would have expected, but maybe when I get the master black right that will be less.

One thing I am also finding and I wonder if you all agree or not, is that whether I use CINE 1, 3 or 4 I can always get back to the same end result in post. So are we making too much of all this?

Mike
Hi Mike,

In the shot above if I had used Cine 4, I would have lost his shorts or blocked up a crumbling whitewater into a solid white mass. Some of that may have been recoverable in post, but not all. I posted the example above because it is a pretty easy shot of what I see. In brighter sunshine it gets trickier again. This shot has no "pop" but it is safe, and a very quick adjustment to finished.
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Old March 13th, 2008, 11:40 AM   #325
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Randy: Your Vectorscope shows the blacks pulled right down, in fact a small bit of black clipping it looks like. I'm asking, for this shot, what did the EX1 histogram show? Did that show a little black clipping to match the scope? A pity you did not post the same shot with the master black at -4.
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Old March 13th, 2008, 12:49 PM   #326
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Originally Posted by Michael H. Stevens View Post
Randy: Your Vectorscope shows the blacks pulled right down, in fact a small bit of black clipping it looks like. I'm asking, for this shot, what did the EX1 histogram show? Did that show a little black clipping to match the scope? A pity you did not post the same shot with the master black at -4.
Yup, after all, negative "black" is about pulling the blacks down, but the black or sub black areas are corresponding to the cracks in the rocks, which one might want at true black, and which one would not likely want to raise in post. This is, however, another example of how we are flying blind with the Vegas scopes in some instances. Take the photo, open it in photoshop, choose levels and hold down the alt key while dragging the black handle and then the white handle to show what channels are blown. You will see a few blown pixels on both ends in certain channels. ***BUT*** the screen shot was taken from 8 bit where the waveform reads somewhat correctly. The photo was taken from 32 bit, where the Waveform showed severe clipping on both ends.

As for the EX1 histogram/TV Logic Vectorscope, the posted screenshot is similar to what I recall seeing. I watched the waves break for a while on scopes and exposed for the brightest moment. Most of the clip was not as close to the top (or right). -8 or -12 would have pushed it through the floor. -4 or 0 would have been fine and easily fixed in post, but I am trying to get to a point where that is less necessary.
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Old March 13th, 2008, 01:32 PM   #327
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Hmm... Sounds convincing, have to re-check. So are you saying that Black is what is often called Master pedestal?
Hi Piotr, Ive come across with that a couple of times. There have been some older Sony CCU:s (camera control units) where the master black level control has been labeled "master pedestal". So, analogue or whatever, it serves the function.

BTW, Ive been reading this group for a while now since Im about to buy a personal camera and the ex1 has been on the top of the list.
What strikes me in a glance is the topics: abrupt highlights, vignette problems, backfocus issues, horrible dvds, workflow problems.

Quite simply, are you happy with the camera?

This should probably be a topic on its own but I was very convinced about the ex1 after seeing it in IBC but now really having second thoughts about the purchase.

Regards, Mika
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Old March 13th, 2008, 01:46 PM   #328
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Actually we hate the camera!.. LOL

Actually, Sony has had a handfull of QC issues, that's for sure.
I'm a little surprised too.

My only issue is a slight vignette which is not seen very often.
Other than that, this is by far the best camera I've used in the sub $10K market.

The image quality is excellent.

For DVD transfers, I see these posts from every camera, regardless of HD or SD.
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Old March 13th, 2008, 02:17 PM   #329
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Mika, I agree with what Steven has just said. I'm fortunate enough to not suffer from vignetting (well, not noticeable), or backfocus problems. Hardware-wise, my only gripes are about the way the ND filter switch is working. As far as downrezzing to SD DVD is concerned, I don't see it as a problem limited to this particular camera, either.

The image quality can indeed be marvellous, and most people think the "abrupt highlights clipping" is a peculiar feature rather than a flaw. I personally wish the way it handles highlights compression around the knee point was improved by Sony via some firmware update, but doubt they will do it - so I'm trying to harness it or live with it.

Frankly, there is no other camera in this price range that I'd like to replace my EX1 with; that said, there is a lot of things that could be improved, anyway...
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Old March 18th, 2008, 07:16 AM   #330
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to all potential EX1 buyers, frightened by this thread

Well, several days after my last post in this thread, I must repeat (and pronounce it): the "abrupt highlights clipping" problem has probably grown much out of proportion in my early experience of the camera. I have since mastered the ways to avoid it almost entirely... And I almost feel guilty when I realize my unit is free from the real, serious issues, like:

- vignetting (I managed to spot it just once, in the upper right corner - but with a whip pan and OIS on)
- back focus
- handle zoom rocker problem
- any CA
- anything else, actually :)

Add to that what Adam Wilt says comparing this machine to some highest-possible-end cameras, and I am quite happy. Of course, some gripes still hold:

- the lousy ND filter switch (and some other switches, none of which can spoil your run'n'gun shooting like the sticking ND filter can, though)
- difficult WB-ing
- red cast on black (or magenta on dark blue), especially fabric under tungsten

But all in all, this is a marvellous camera. I hope for all you guys to get yours fixed or replaced soon, and for the new buyers - to get problem-free units the first time!
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Last edited by Piotr Wozniacki; March 18th, 2008 at 09:39 AM.
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