Very good point Piort. I knew this and totally forgot the problem of the Zebra #1 95 being 90-100.

Actually, it will appear everywhere between 85 and 105%, Mike.

Maybe, if you set Zebra #1 to 100, then when zebras FIRST appear you are at 95?????????

It will then appear between 90 and 110%.

None very useful for highlight clipping control. Very good for your main subject (e.g. human skin) controlled exposure.

I think I should add that I find the solution of Zebra1/Zebra2/histogram very useful and properly thought-through by Sony.

- zebra 1 for controlling your main subject exposure (e.g. face skin at around 70%), and only activated when needed (to avoid cluttering of the VF)

- zebra 2 fixed at 100% and always on, to control and prevent clipping when possible

- histogram: this is a bit more complicated, but also works properly. For example, with Cine2 it will never go to the very RH end (zebra 2 is never triggered within the resonable overal exposure of your scene). So, how can one control the highlights exposure? Well, just try this: overexposure by 2-3 stops and - even though the Zebra 2 is still absent - you will notice a vertical bar at the RH end of the displayed histogram range (NOT at 100% - a bit to the left of it). This is because Cine2 will compress highlights enough to never exceed 100% - now turn the exposure down, and you will see this vertical bar going down... Try to make its hight more balanced with the rest of your histogram, and you'll be fine.

With the STD1 being the opposite extreme, the vertical bar can appear at the most RH end of the histogram scale, which of course is confirmed by the Zebra 2: you're clipping at over 100%.

- you will notice a vertical bar at the RH end of the displayed histogram range (NOT at 100% - a bit to the left of it). This is because Cine2 will compress highlights enough to never exceed 100% - now turn the exposure down, and you will see this vertical bar going down... Try to make its hight more balanced with the rest of your histogram, and you'll be fine.

.

Thanks Piotr: I have been taking that vertical line right down to zero when using the histogram. I'll try your way.

Thanks Piotr: I have been taking that vertical line right down to zero when using the histogram. I'll try your way.

There's certainly no reason to take it down to zero, Mike - it represents pixels with completely legitimate exposure (brighness) value! Of course, I'm talking now about the cine gammas, which generally prevent from clipping above 100% - compressing everything gracefully much "to the left" of 100% (especially the Cine2 gamma).

Reading about the ongoing problems that so many users have with their camera's vignetting and/or backfocus, I'm thinking the "abrupt highlights clipping" can indeed be treated as a "peculiarity" rather than a flaw...

On the other hand, while the vignetting (or even backfocus, as it seems to depend on the ND filter use) might be difficult to fix (the worst scenario being they're inherent in the design's tight tolerances, and/or ND filter implementation) - the knee/hightlight compression algorithm is a purely software issue, so I'll appreciate input from people like Adam Wilt or Leonard Levy or Tom Roper, who appreciate this problem - it would help greatly in articulating our wishes for some future firmware update in this regard.

There's certainly no reason to take it down to zero, Mike - it represents pixels with completely legitimate exposure (brighness) value! Of course, I'm talking now about the cine gammas, which generally prevent from clipping above 100% - compressing everything gracefully much "to the left" of 100% (especially the Cine2 gamma).

Really only Cine 2 will limit to 100%. On 1, 3 and 4, the curves will deal with the rolling of the whites nicely under 100%, but rescuing whites above 100 can be more work. I think Michael was on the right track. Find Zebra 100, and back off till none. Then use the black level that best pulls the histogram (or waveform) to your floor.

This is what I am considering pushing right "with safety" on this camera.

Find Zebra 100, and back off till none.

Exactly what I've been saying (and doing), Randy.

holy mother of God! I've said that since day 1!
http://www.dvinfo.net/conf/showthread.php?t=110902&page=9 see post no. 128
Welcome to the club.

But so have I, Bill - like here: http://www.dvinfo.net/conf/showpost.php?p=824239&postcount=174

"- if in manual iris mode, with zebra set to 100%, never allow ANY zebra in the sky (some traces only allowed in pure white areas, like birch barks; the sky - even cloudy - is NEVER pure white so NO zebra there!)"

Me too....

..................................................

Really only Cine 2 will limit to 100%. On 1, 3 and 4, the curves will deal with the rolling of the whites nicely under 100%, but rescuing whites above 100 can be more work. I think Michael was on the right track. Find Zebra 100, and back off till none. Then use the black level that best pulls the histogram (or waveform) to your floor.

This is what I am considering pushing right "with safety" on this camera.

JUST SO THERE IS ABSOLUTELY NO CONFUSSION do you mean "black level" and not "black gamma"? If you DO mean "black level" what do you do, if anything, with "black gamma"? Is that just for the internal strech - ie detail vs noise?

"Black" shifts the middle (gray) level of the gamma curve, while "Black gamma" is responsible for what on many prosumer cameras is called Black Stretch/Compress.

My experience from the much less light-sensitive (and hence noise-prone) V1 us that if noise is potentially a problem, you'll be better off crushing the blacks to get rid of it (along with details in dark areas, but I personally prefer such picture than a stretched one, with lots of detail and chroma noise).

"Black" shifts the middle (gray) level of the gamma curve, while "Black gamma" is responsible for what on many prosumer cameras is called Black Stretch/Compress.

My experience from the much less light-sensitive (and hence noise-prone) V1 us that if noise is potentially a problem, you'll be better off crushing the blacks to get rid of it (along with details in dark areas, but I personally prefer such picture than a stretched one, with lots of detail and chroma noise).

Piotr: I know quite well what Black Level and Black Gamma are I was asking Randy wht settings he used.

Oh, sorry - was reading too fast :)

"Black" shifts the middle (gray) level of the gamma curve, while "Black gamma" is responsible for what on many prosumer cameras is called Black Stretch/Compress.


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.

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?

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?

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.

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. :)

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?

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.

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

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

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.

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.

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.

Hmm... Sounds convincing, have to re-check. So are you saying that Black is what is often called Master pedestal?

Hi Piotr, I´ve 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, I´ve been reading this group for a while now since I´m 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

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.

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...

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!

The "flat spot" is present in all PP's and is very relevant to me, because it explains a lot about how whites are being handled.

Guys, referring to the last development in that other thread - how do you interpret the "abrupt clipping" phenomenon, in the light of SAW results?

Hi Piotr,

No idea what is happening with individual color handling up there. All I can tell you, is that the luminance curve flattens at it's highest value on each PP.

When looking at the curves in the brochure, I had been confused as to why the curves all ended at a different point on the horizontal axis, but now it makes sense. In actuality, the top value simply flat-lines to the right after the final depicted point. I think that is valuable to know.

What I'm wondering is this: with STD curves, when you change the knee point and particularly the SLOPE value - what does the flat fragment look like?

What I'm wondering is this: with STD curves, when you change the knee point and particularly the SLOPE value - what does the flat fragment look like?

Hi Piotr,

Probably easier for me to snap some shots and show you. Are you interested in a particular Gamma, say STD 3?

Hi Piotr,

Probably easier for me to snap some shots and show you. Are you interested in a particular Gamma, say STD 3?

Randy - all, if possible, please! But of course I appreciate your time and effort :)

The thing is that while the CINE curves are depicted in the brochure, the STD ones cannot be found anywhere...

Hi Piotr,

Probably easier for me to snap some shots and show you. Are you interested in a particular Gamma, say STD 3?

Randy: I would like to see screen snapshot of Cine 1 and 4. But please tell me what is "SAW"?

Dzen dobri Piotr:)
Maybe you filmed candle's flame? If no...maybe you can try this test? Would be very interesting,thanks:)

Dzien dobry, Raimis :)

Filming candle flames is something that naturally requires a lot of attention to properly exposing, thus is less prone to exhibit the "abrupt clipping" effect than those seemingly easy shots outside, with plenty of light...

Or do you mean some other peculiarity that might be revealed?

For me interesting how will does EX1 this test with candle,for example HDV sony compression has artefacts around flame:(

Compression is one thing (and of course the 35Mbps VBR of the XDCAM EX HQ codec is far superior to HDV), but how this area is rendered depends mainly on the imagers (CMOS will give you the halo, while CCD - the ugly, vertical smear).

This thread, however, has dealt with something quite different; I'm sure you're aware of that :)

Dzenkuja barzo for your answer Piotr!:)
But if you'll have free time,would be interesting how XDCAM EX HQ codec will pass this test with candle:)

I will, Raimis. But considering it's also CMOS, expect the halo to be there, as well. Certainly close to none compression artefacts, though...

I saw these artefacts with consumer camcorders HDR-HC1,HC3,HC5,HC7 and new HC9E(AVCHD camcorders have not this problem) and i tested with candle semi pro camcorders HVR-A1,V1,FX1,FX7...everywhere is same problem:) I'll hope everything is fine with amazing EX1/3 camcorders:)

Guys,

To sum this thread up somehow (being one of the longest in this forum, it kinda deserves it :), I must say that after mastering my EX1 I don't find the "abrupt clipping" phenomenon as disturbing as I initially thought. I must agree with Adam Wilt that the problem is practically absent with CINE gammas (though it can show its ugly head from time to time, as well).

As to the STD curves, I find it appear most often when using STD3 (which is strange, as this is the default gamma, in force when you don't use any PP). STD1 and STD4 I'm using almost exclusively with my PP's for indoor, lowlight shooting (when I need to either get a punchy look, or stretch blacks - respectively); in this sort of lighting the abrupt clipping is practically non-issue at all.

Nevertheless, for purely academic reasons, I'd like to see some well-grounded recipe for knee adjustments that would control the phenomenon even with STD curves outdoors. Also, I wonder is Sony's going to address it in future firnware releases (or rectify it in the EX3, for that matter)...

Further on the above, I'd like to encourage everyone to try and experiment with the KNEE APERTURE settings (this is a function to tune edge enhancement solely in areas, affected by the highlights compression, i.e. to the right of the KNEE point):

http://pro.sony.com/bbsccms/assets/files/micro/xdcamex/solutions/Reproducing_Solid_Picture_Edges.pdf

My experiments (though yet inconclusive) tend to show that the default setting of KNEE APERTURE is not the best one, and may add to this "abrupt clipping" phenomenon. Along with the KNEE Saturation and SLOPE, it can be set to get rid of this ugly effect altogether; pity though that the default settings (especially with the STD3 gamma) are such that with run&gun shooting style, it's not always possible...

I'm very curious of your own observations.

Probably many of you guys have already find out that simply turning KNEE AUTO off (even while leaving it at the default 90%, with a possibility to tweak it further should need be) - allows to get rid of the "abrupt highlights clipping" artifacts discussed in this thread.

FWIW...

A very old thread of mine, revived :)

But don't you worry - no ranting this time. Just to add what others may have noticed in the meantime:

- the blueish glow behind the tree branches when shot backlit can be intimidated not just by using a CINE gamma or special Knee settings in STD gammas (for better roll-off), but also by adopting a warmer overall color temperature...

The below grabs show the idea (the effect has been exaggerated to make what I mean obvious).

HTH

Piotr

PS: Sorry - those grabs here lack contrast for some reason - is it how DVInfo handles them, or what? Anyway, the way they're rendered denies my point completely; those interested please download them and add some contrast to see what I mean :)