FS5: Easiest way to get 1.5 - 2 stops over for shooting S-log?

How does the FS5's faux Rec709 VF LUT affect the zebra levels?

Is it just a VF trick and the zebras are still referencing the SLog2 signal or will the zebras measure the LUTed signal?
 
Grug said:
Good lord... the complexities you guys go through for exposure just boggle my mind.

I'll make the suggestion one more time then leave this thread well alone - get a lightmeter. Zebras are just irritating (both visually, and as a means of setting exposure)
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As stated earlier, it takes about a second for me to set exposure and confirm it is correct using any one of the techniques mentioned in this thread. It's not something I ever stress about. I used to hate zebras. Absolutely loathed them. And even now I only flick them off as quick as I can

BTW I have two light meters. They sit on the shelf mostly:-)
 
Doug Jensen said:
Well, you're wrong on pretty much every statement that you have made in your post. And I don't really understand what you are implying with your "suspicious" comment. Do you think I am hiding something or not telling the truth about how i use zebras?


Why would I do that? I am on record for explaining the differences between the two zebras, what targets to use for zebras, and the proper use of zebras in all of my camcorder training videos so there is nothing to hide or questions to evade here. But I do find it odd how you post statements about zebras as if they were facts and then expect other people to step in and refute what you have said. BTW, if you go back up and read what I wrote in post #11 you can see that I did explain how 70%-75% is overexposing by two stops.
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It was in jest.
 
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I just use the scopes and adjust the iris until I see the peaks compressing, then back off just until the peaks rebound.
 
basspig said:
I just use the scopes and adjust the iris until I see the peaks compressing, then back off just until the peaks rebound.
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That might work for a DSLR shooting RAW stills, but for professional video, exposure needs to be quite a bit more precise and consistent than merely avoiding clipping highlights. This is especially true if somene is shooting Hypergamma or S-LOG curves. They are curves and you can't just push everything to the redline and call it good.
 
It may be a matter of taste, but I don't like the look of clipped highlights. I've also noticed that as you push upwards on the S Log curve, the upper mid tones start to look flat.
I always grade to -2 stops with my LUT set up that way, which gives me a good start on controlling noise. Recently, I discovered I can recover a couple more stops of highlight by placing a ProcAmp plug in ahead of the technical LUT and reducing the contrast to 80%. All the tweaking to highlights, white point and exposure in post can't get back that highlight information because it's already clipped either by the LUT itself, or the underlying engine of the software.
But my 'best practice' when shooting is to rely on the waveform. It's not just minor highlights, but the whole upper range that should be considered when adjusting exposure. As you open the iris, you can see how the whole upper third of the waveform starts to compress. That is what I try to avoid. I tend to shoot 'low key' because it gives richer contrast and colors in the mid tones. Of course, it depends heavily on which LUT you are using. Some LUTs roll back saturation as exposure increases. So in the final analysis, I evaluate what I see in the VF as well as verify it on the WFM.
 
sounds like you are getting a lot of noise, slog loves light
which luts do you recommend?



basspig said:
It may be a matter of taste, but I don't like the look of clipped highlights. I've also noticed that as you push upwards on the S Log curve, the upper mid tones start to look flat.
I always grade to -2 stops with my LUT set up that way, which gives me a good start on controlling noise. Recently, I discovered I can recover a couple more stops of highlight by placing a ProcAmp plug in ahead of the technical LUT and reducing the contrast to 80%. All the tweaking to highlights, white point and exposure in post can't get back that highlight information because it's already clipped either by the LUT itself, or the underlying engine of the software.
But my 'best practice' when shooting is to rely on the waveform. It's not just minor highlights, but the whole upper range that should be considered when adjusting exposure. As you open the iris, you can see how the whole upper third of the waveform starts to compress. That is what I try to avoid. I tend to shoot 'low key' because it gives richer contrast and colors in the mid tones. Of course, it depends heavily on which LUT you are using. Some LUTs roll back saturation as exposure increases. So in the final analysis, I evaluate what I see in the VF as well as verify it on the WFM.
Click to expand...
 
basspig said:
It may be a matter of taste, but I don't like the look of clipped highlights. I've also noticed that as you push upwards on the S Log curve, the upper mid tones start to look flat.
I always grade to -2 stops with my LUT set up that way, which gives me a good start on controlling noise. Recently, I discovered I can recover a couple more stops of highlight by placing a ProcAmp plug in ahead of the technical LUT and reducing the contrast to 80%. All the tweaking to highlights, white point and exposure in post can't get back that highlight information because it's already clipped either by the LUT itself, or the underlying engine of the software.
But my 'best practice' when shooting is to rely on the waveform. It's not just minor highlights, but the whole upper range that should be considered when adjusting exposure. As you open the iris, you can see how the whole upper third of the waveform starts to compress. That is what I try to avoid. I tend to shoot 'low key' because it gives richer contrast and colors in the mid tones. Of course, it depends heavily on which LUT you are using. Some LUTs roll back saturation as exposure increases. So in the final analysis, I evaluate what I see in the VF as well as verify it on the WFM.
Click to expand...

This totally contradicts your post #24 where you state you are pushing the exposure to the point of clipping and then backing it off a little. So which is it?
And BTW, clipped highlights is not a matter of taste. With the exception of specular highlights it is always wrong.
 
Doug Jensen said:
This totally contradicts your post #24 where you state you are pushing the exposure to the point of clipping and then backing it off a little. So which is it?
And BTW, clipped highlights is not a matter of taste. With the exception of specular highlights it is always wrong.
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No I didn't contradict myself. I observed that not only the highlights compress, but the upper third of the midtones. Noting that the upper third also compresses does not contradict the fact that the highlights compress. Why are you such a contrarian, Doug?

I see a lot of clipped and badly blown "high key" video in Korean drama TV programs. On the one hand, back in analog days, you wanted to stay above the noise, given the video signal was on an AM carrier, which is prone to noise, so shooting high key was a habit many network camera ops adopted. But today in the realm of digital, it just looks bad.


Compared to my Sony EX3, I guess you could say the noise is much less, but the fact that I can still see noise on my DCI 4K display at 1:1 pixel mapping has me being cautious to use minimum gain through shooting as hot as possible without clipping anything important, and then backing off exposure in post to push all the noise down into the blacks. The FS7 only has 57dB of s/n ratio. Compared to audio, which is up around 100dB, video still is in the realm where magnetic analog tape was in the 1960s--you have to maximize the signal without distortion (clipping whites) and stay above the noise at the same time. One day, we won't have to worry about working to such tight constraints, when sensors have 100+ dB s/n ratio, but for now, video is way behind audio in that area.
 
Ok, I spent yesterday shooting Slog2 for the client and have another 2 days yet to shoot. They used a Sony A7Sii as there B-camera, apparently in Slog2. They were quite surprised at how different their/my Slog2 looked both on the camera monitors and when pulled into Premiere. Theres was considerably flatter/desaturated/milkier than my FS5. They did a quick grade and had no issues with my FS5 slog2 rushes, but nonetheless they were't expecting to see a difference.

Just to clarify I have pretty much followed all the advice I've been given or have read. On my FS5 I am using PP7 with S-Gamut at 5500K (and all lighting is daylight). My zebra 2 is set to 70% and I'm using a lastolite white card to see where zebras are kicking in (and thus should be +1 stop over). Sure enough if I switch the gamma assist on, then what I'm seeing on my FS5 monitor looks a little hot by about 1-1.5 stops.

So am I missing something or is there just a significant difference between the FS5 and the A7Sii in Slog2?
 
Well they are two different sensors shooting two different codecs with different processing hardware.

Not a huge surprise there is a bit of difference. Very easy to shoot a chart with both cameras on same lens/aperture etc, bring them into resolve and correct the A7 footage so it is identical, before saving that as a colour correction LUT to apply to all your future A7 rushes.
 
Zebra aperture width

Zebra aperture width

Liam Hall said:
Zebra 1 will show a range of IRE values dependent on the value you choose and the size of the aperture you select. Fine for finding mid-tone but easy to miss when adjusting exposure quickly. Zebra 2 is much more useful when using it to find highlights as it will show all IRE values beyond the one you set.
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Ahhhh, good to know. I didn't realize the Zebra aperture width only effects Zebra #1. Thanks for the clarification.
 
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