Should Red Logfilm be exposed differently

[Jake Wilganowski]

there something to be said about the highlight rolloff when shooting at higher iso's, not getting into a noise debate, I don't think the rolloff can be EASILY emulated in post, putting whites way up there next to clipping makes your grading more extreme, anyway, that's the beauty of this camera, so many possibilities

 

[David Mullen ASC]

RedLogFilm and Rec.709 are all conversions from raw, so if the same exposure looks one way in Rec.709 and another in RedLogFilm, then clearly they were designed to work that way, right or wrong. Some people have the same issues with recording S-Log on the Sony F55, they feel that the log recording seems a bit low and they try to compensate by exposing more. Or simply by just using a lower ISO value.

 

[Marc Wielage]

Thanks. This is exactly what i was after. I guess my clients expose a bit like ENG camera and they try to expose it low but should ETTR.

I have run into underexposure problems before, and I've had to (painfully) sit with the DP -- with nobody else in the room -- and show them the histograms and why there isn't enough signal to create pictures with reasonable noise levels. I think some of these guys overreact to the panic of an on-set situation and try too hard to keep every bit of specular highlights out of the clips, which can't be done in some situations. We need a fatter signal to make decent images.

I do feel your pain, Margus -- we've all been there and done that in post, and a lot of the time the pictures wind up with compromises because of the way they're shot, not because of anything being done in color-correction. It does not help when you find out they didn't have a calibrated monitor in the field and were just trusting a laptop or some other $399 monitor of questionable image quality.

I'm a fan of down-the-middle exposures where they just make it more or less "normal," with an eye towards creating a stylized look in post. It helps if they have time to do camera tests and learn where the limits are. Unfortunately, not all productions are willing to spend a day to do those tests and involve the colorist.

 

[Marc Wielage]

there something to be said about the highlight rolloff when shooting at higher iso's, not getting into a noise debate, I don't think the rolloff can be EASILY emulated in post, putting whites way up there next to clipping makes your grading more extreme, anyway, that's the beauty of this camera, so many possibilities

Controlling where and how whites clip is an important adjustment in post, and I think there's a way to do it without compromising the image too much. But so much depends on the lighting, there are no easy, snappy answers. Key-to-fill ratio is still an important consideration regardless of what camera you're using. Too many people want to believe they can use less lighting at high ISO ratings, but the reality is you still need to carve out a workable image there on the set.

 

[David Mullen ASC]

Keep in mind that most log gammas are designed to hold overexposure detail, so you'll find that with Arri Log-C, for example, an 11-step grey scale would have the white patch at only 65% (and middle grey at 40%) because there are a couple more stops of overexposure information beyond that to retain from the sensor. So if you expose log so that whites look white on a Rec.709 monitor, you are actually overexposing the image.

 

[Stacey Spears]

I think some of these guys overreact to the panic of an on-set situation and try too hard to keep every bit of specular highlights out of the clips, which can't be done in some situations.

Sometimes you have to let that ping go, especially if it is not the object of interest. I am guilty of trying to save it all and the footage suffered because of it.

Aren't they a thing of the past? My Dragon is pretty smart at getting good exposures

I think the Weapon has wonderful exposure tools, but I still use a light meter. More so now than I did when I first started shooting on Red.

 

[David Battistella]

Just one thought here.

sometimes it's useful to think of pixels in digital as a bucket. Digital sensors tend to respond better or give you the images you are looking to achieve when you fill those "pixel buckets" with light. If you overfill them (clip to white) you can not recover the information. If you under fill them (starve them) they scream back at you in the form of noise.

Also, try to think in terms of light hitting the sensor rather than just one particular color science. Come up with a strategy for how your histogram needs to look (with whichever color science you choose) to achieve the look you are going after.

As an example, I'll use dc2/rg3 ISO 400 set in camera and really fill the histogram when I am looking for a clean looking frame. For a little more grain I might look to using ISO 800, I rarely have ISO set higher than that in camera.

I still find that 800 ISO in camera is almost a stop of highlight protection. If your style tends to protect highlights, or if you are conservative with highlights, you can often end up with 1 1/2 to 2 stops under exposure.

I find now with dragon, you can push exposure and highlights harder because it handles them much better but I still tend to rate around 320, 400, 500 ISO generally. When I do this I find I have the freedom to "process the footage" at just about any ISO I want to to shape the image. When I rate higher, 800 and above, you get a bit less room to play around as it's hard to process at a lower ISO than you rated at.

Rating lower will tend to produce the fat negative that people talk about and perhaps a more flexible image in post terms.

All this said, I have rated things at 1600 ISO for DOF reasons, tested and went with that workflow after running the image through the pipe. The one thing that is true is that you get a lot of flexibility.

Think of it as exposing the sensor, how much am I filling the buckets of light? instead of the color science and try to weigh those decision against what you intend and what is required.

David