How to overexpose? And how I can recognize it?

S

saw

Member
Sorry, maybe a very stupid beginner question, and its really basic, I have never worked with it, only and always with my eyes, (with pretty good results ;) ) but now is the time for a step forward.
How I can overexpose my footage in slog2? I read that I should do it to avoid noise.
I can shoot 2K Raw with the 7Q.

Lets say Im shooting on a low light situation , lowest fstop, lets say 1,4f.(end of stop)
Im on ISO2000.

If I go higher with the ISO Im expection more noise, so that cant be the way to overexpose it. Right?

So the only way to overexpose is to bring more (physical) light in the scene? Right?

How can i recognize it with the Histogramm? I know how (a litlle) to read a histogramm, but how it looks if its a little overexposed? And what is little?

Thanks !
 
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Honestly, I think we're all still figuring that out a bit... which frankly is a little worrying. I just shot a local commercial with the 7Q... I did this after spending a bit of time shooting a few mini-passion projects and test shoots with it. I've tried exposing it in a variety of manors... by the end, for this last shoot, my method is less mathematical and more instinctual. And yes, you're going to need more light in your scene. I was exposing these scenes to be shot at f/4, and I'd get everything looking right. And then I'd let more light in to the lens... often taking it down to an f/2-f/2.8. I don't like that I'm having to tell you so much variation about how much additional light, but when it comes down to it, you're capturing more than what the histogram or the scope will tell you that you have, and it's important to make that assessment on each shot, since you're half flying blind.

In the end, you have to send highlights over the line, into a space where you can't--at least not emotionally if factually--quite be sure if they're recoverable. I send the top end just over the line, but you have to be comfortable doing that, as the image looks like crap at that point on the monitor, so if you're not confident about it, everyone else on set who has a view of the screen is going to be really worried.
 
The 20 points high suggestions seems to correlate with what I've been experiencing with it. As I said, it's just sometimes unnerving to those watching... even when you know you're doing the correct thing, it's always unpleasant when the image doesn't reflect that--particularly for those not operating the camera.
 
yeah, it's hard to explain to directors and producers that the images they see when recording to SLog2 are OK. That's partly why C-D has the LUT display button. When pressed, it ameliorates the washed out look on the display. But, it also affects the WFM and histogram, which it should not! This is a bug, as I understand it.
 
cuervo said:
yeah, it's hard to explain to directors and producers that the images they see when recording to SLog2 are OK. That's partly why C-D has the LUT display button. When pressed, it ameliorates the washed out look on the display. But, it also affects the WFM and histogram, which it should not! This is a bug, as I understand it.
Click to expand...

Yes, this should be fixed pronto. I was transcoding some 7Q footage at my Directors studio and he saw the Slog-2 clips and he was like: "What is wrong with those shots? Is that how the footage is going to look?" On set, people would probably be even more freaked out.
 
cuervo said:
yeah, it's hard to explain to directors and producers that the images they see when recording to SLog2 are OK. That's partly why C-D has the LUT display button. When pressed, it ameliorates the washed out look on the display. But, it also affects the WFM and histogram, which it should not! This is a bug, as I understand it.
Click to expand...

ok so will this setup be a permanent thing? Or, when this is fixed in a future firmware update, will the image then look normal/pleasing to the eye when the LUT is on - but flat when LUT is off?
I'm imagining something like switching between RED raw view and rec.709 on a RED camera - where the latter will look fine to a client. If not is there another LUT on the way from CD to adress this?
 
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tscav said:
ok so (coming from someone who is still waiting for his unit) when this is fixed, will the image look normal/pleasing to the eye when the LUT is on and on off when its in slog2 mode? I'm imagining something like switching between RED raw view and rec.709 - where the latter will look fine to a client. If not is there another LUT on the way CD?
Click to expand...

yeah, that's the idea. And, I beleive the plan is to allow users to input their own LUTS to simulate whatever final look they want.
 
One should never use gain or ISO changes within a scene to control exposure IMO. So much changes with camera calibration when you change ISO speed that it is hard to get a consistent shot to shot look that way.
Use aperture and shutter speed/angle changes only.
Pick ISO for a scene based on what gives a correct middle gray exposure for the average lighting conditions and leaves a +/- 2 stop aperture range to change shot to shot exposure. Typically this will be f2.8 to f4 using fast lenses, at least 2 stops down from wide open. If you must shoot wide open for DOF reasons, use ND's to control exposure.

The only way to properly overexpose is to have more light than you need on the scene.
ISO settings for digital cameras are a bit counter intuitive. Setting a higher ISO or gain makes you underexpose to compensate.
2000 ISO is supposedly native for S-log, but it forces under exposing by a stop. Middle gray winds up at or under 40% instead of 50%.
Try lighting and shooting at a lower ISO for overexposure.
 
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