Cine gamma settings in the EX1

[Joe Lawry]

Originally Posted by Leonard Levy

Joe may prefer Cine gammas for many reasons , perhaps all are legitimate but to declare that std gammas are horrible is off the charts to me. i use them all the time with excellent results.

If you can to post some Settings for Profiles using the Standard Gammas I'd definitely be keen to put them into my camera and give them a try!

The few times i have shot with standard gamma and have had poor results and as soon as i found Bills TC profiles i was hooked on the Cines.

I have also seen a lot of bad EX1 footage around the place, and i can tell by either cutting the footage, or just watching it in shows on TV that there are many people here in NZ shooting with the standard gammas and the camera still setup out of the box. So i guess this has just put me off doing more experimentation with them.

Every client i shoot for, whether it be interlaced or progressive has liked the Cine Gammas.

But like i said, if you want to put up some profile settings or link me to a post that has some good ones im keen to have a play.

[Andy Shipsides]

If you plan to use the Std Gammas instead of the Cine Gammas then make sure to turn off Auot Knee (which is on by default) and then set your knee point and slope. There is nothing wrong with Std Gammas but the Cine Gammas will give you more dynamic range in general. As has been said before Cine 1 & 2 will compress highlights so that you will get more range in bright scenes. Cine 3 & 4 bring up the low end of the gamma curve so they work better in low light scenes. I would never use Cine 3 or 4 outside on a bright day, unless I was shooting into the shadows.

Gamma isn't changing your skin tones, it's not a color change at all. It's more like a contrast change in the mid tones.

[Leonard Levy]

John, I'm not sure what you mean by nasty skin tones. If its a color issue that should have nothing to do with cine gammas. However I suspect you are seeing compression in the brighter parts of the flesh tones that looks nasty with the Cine Gammas. That's why I don't use them based on my first tests with the camera.

I suspect that can be overcome by exposing a little lower than you normally do to keep flesh tones lower out of that compressed area. I plan to do some testing on this one of these days to see if I can make the cine gammas work for me. But I thought it was dangerous wherever there were skin highlights. Especially on backlight subjects.

How do those of you using cine gammas deal with this?

[Alister Chapman]

The cinegammas are designed to be graded. They work best when your skintones are right in the middle of the curve so somewhere between 55% and 65%. This is a little lower than you would expose using the standard gammas. The idea being that skin tones are in the most linear, uncompressed or stretched part of the curve. That gives you the maximum leeway in the grade. If you over expose skin tones even a little using the CG's will will start running into compression issues which will skew the colours.

If you are finding that your overall pictures are red or have a red shift try using the Cine Matrix with the level set to +35. I find the cine matrix has a more natural response than the standard matrix.

You can get just as much lattitude using the standard gammas as the cinegammas, but you will have to set the knee point and slope to the appropriate levels for the scenes you are shooting. Careful use of Knee and black gamma can give very good results without affecting the way you expose skin tones and requires less grading for a pleasing looking picture. I use standard gamma 2 or 3 with the knee set to 85 and slope at +10 as a general setup where I don't want or need to grade.

[Leonard Levy]

Alister,

I also go with Standard gammas ( STD3 ) and agree about no Auto Knee, but my tests found setting the point at 85 to be dangerous ( unwanted compression) though I probably tested with a slope of 0.

I've set mine at 93 with 0 slope as a general setting but I'll try yours out.

[Simon Wyndham]

85 is generally considered low for standard gammas. The danger is that if you expose skin tones in STD gamma at around 75% or even 80% there is a risk of compression in harsh lighting when you need to compromise with the exposure.

95% I think it more sensible for general use in many cases, although 85% can be used with care. I wouldn't touch the knee slope unless you can measure things properly. Set up correctly, as Alister states, you can actually get just as much range out of the STD gammas as the Cines. But you really need to know how to set up the black gamma and knee slope.

A good starting point is STD gamma 4 ("BBC gamma"). The trouble is that setting up the standard gammas in this way leads to less pleasing roll off in highlights because unlike the cinegammas there is no smooth transition from the shadows to the midtones to the highlights AFAIK.

The Cinegammas were meant to be graded, however I would really apply this more to 1 and 2. I regard Cine 4 to be more like Panasonics Video Rec cine curve and good for general use even without grading.

Regarding exposure with the Cine curves, you have to be careful with skin. As Alister rightly points out you should expose at a lower level to what you might be used to on STD gammas. One issue here is that you also have to be careful of under exposing. There is a sweet spot that is just right, but miss it and things can look a bit odd, especially in the shadows too.

[Gavin Rawlings]

Anyone know roughly how many stops of latitude the EX1 has? Say, for example, using Cine Gamma 1?

[Simon Denny]

I have done a few test with the Cinegammas.
This is nothing new for anyone but I want to explore what is happening.
I set up a shot with my Wife with natural light coming into the room and exposed to her face @ -3db,f 4.8. Zebras set to 70% and then 80% moving to 100%, lighting stayed the same exposure for this quick test.
This is by no means a proved scientific method but I use what I have.
Cine 4, exposed Zebras all over face @ 70%, less @80% reducing to none @ 100%
Cine 3, exposed Zebras 1/3rd of face @ 70%, less @80% reducing to none @ 100%
Cine 2, exposed Zebras none over face @ 70%, none @80% none @ 100%
Cine 1, exposed Zebras just a strip @ 70%, none @80% none @ 100%

So my conclusion is I found Cine 3 to produce the best. A pleasing tone in the blacks and also a nice soft tone on the top end.
Cine 4 is great for situations where overall brightness need to come up in the scene such as a wedding reception room or something similar.
Cine 2 is great for bright harsh outdoor situations where top end needs to be clipped.
Cine 1 is also great for outdoor situations but leaves the top end a bit more intact.

Conclusion for me to use on my next shoot tomorrow. Live gig to Imag
Cine 3 best overall for indoors.
Cine 1 solid for out door situations.

Cheers

[Alister Chapman]

The EX has around 11 stops of latitude when using CG1, CG3, CG4 or with Std gamma plus correctly set knee.

I find having the knee on the EX at 85 with the slope at 15 works well for me, but then most of what I do doesn't involve interviews, instead having to deal with high contrast exteriors.

[Serena Steuart]

OK, I've redone the gamma curve plots. Just for Cine 4, Cine 1 and STD 1 (knee off). The wiggles at the bottom of the curves due to data uncertainty.

[Piotr Wozniacki]

Thanks, Serena.

Guys, do you see now why I'm using STD1/STD4 for low-light indoor shooting? Especially with Letus adapter...

[Vincent Oliver]

Originally Posted by Bill Ravens

Piotr...thanx
Vincent...hmmm, non-sequitor in the context of this discussion ;o)

The moral of my post was don't worry how the engine works, just get out there and enjoy the ride.

Whilst I appreciate that fully understanding how each of the gammas effects the picture quality, and your detailed knowledge on this matter. I feel that many people spend far too much time with their heads under the bonnet rather than getting out and using their gear. The same holds true for most matters related to digital photography, I am not sure why, perhaps it is the very technical nature of the industry that attracts a tinkering mind.

[Bill Ravens]

Serena...
Can you share with us how you abtained this data? Is it empirical or predicted? The knee of the S1 curve shows a bit of overshoot, which I would guess is data scatter? If it's real, there will be some serious distortions(non linearities) in high-lites of the image. Plotting this with a log scale on the abscissa makes the data look less serious than it may be.

Vincent....
you are referring, of course, to pixel peeping.
it's a good thing to find balance and moderation in all things. however, since this thread is about some of the more technical aspects of filming, and not the esoterics, I do wonder what reminding us of aesthetics brings to the table.

[Barry J. Anwender]

Originally Posted by Vincent Oliver

The moral of my post was don't worry how the engine works, just get out there and enjoy the ride.

Whilst I appreciate that fully understanding how each of the gammas effects the picture quality, and your detailed knowledge on this matter. I feel that many people spend far too much time with their heads under the bonnet rather than getting out and using their gear. The same holds true for most matters related to digital photography, I am not sure why, perhaps it is the very technical nature of the industry that attracts a tinkering mind.

Vincent, a good analogy when a useable/workable/real-world manual is provided to explain how to use its features. In Sony's case, they have failed to provide us with any meaningful documentation on how to actually make good practical use of all the features contained in the Picture Profiles. This same point was mentioned earlier (above) with the question as to why Sony is so secretive on this subject. While Sony's "Creative Shooting Techniques" are an attempt to shed some light on the topic, they only scratch the surface. Hence, we left to explore-share-debate-learn from real world experience.

Thankfully we have this forum to express the need for this thread, as well as the good folks who are willing to generously give of their time-talent-experience for the benefit of all. Cheers!

[Vincent Oliver]

Originally Posted by Bill Ravens

Vincent....
you are referring, of course, to pixel peeping.
it's a good thing to find balance and moderation in all things. however, since this thread is about some of the more technical aspects of filming, and not the esoterics, I do wonder what reminding us of aesthetics brings to the table.

Bill, without your and others knowledge we would be totally stuck, or at worst not get the best results from our gear. Despite my comments, I do appreciate your input. I just want to remind people that the goal of the technical knowhow must be to add to the end result, and that surely must come back down to creative "filming" (sorry an old fashioned term for shooting pixel data).

Everything in moderation, but not to the point that some of us are losing the plot.