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  • Hey all, just changed over the backend after 15 years I figured time to give it a bit of an update, its probably gonna be a bit weird for most of you and i am sure there is a few bugs to work out but it should kinda work the same as before... hopefully :)

Log/Rec.709, Headroom, and Dynamic Range....

One way to build underexposure into your image without a LUT is to rate the camera at an ASA above 320. Do that and you can place skintones, etc where they look good on the monitor and still have highlights to recover later.

Of course this all happens at the expense of the noise floor.
 
wow!!!, so much time on ones hand's.

Useful if you need to know this information, but at the end of the day, content will over ride latitude.

You can shot a movie on super8 and win Oscar for cinematography if done well.

Thanks for the info none the less,
Interesting read.
 
Here's a question:

When every theater has switched to digital projection does shooting underexposed to allow for the headroom of film become pointless?

More importantly, does it in fact hurt your digital theatrical "print" because you've introduced more noise than was needed?

Seems that I could wind up shooting underexposed for the film print that is going to be in theaters for a couple weeks in 2009 and wind up with a lower-quality version that people will watch for the next 50 years on their home 4K projectors once the price on those drops to $500 (which will happen eventually, with Moore's law and all that...)
 
I read the whole article and I can't agree with what he is saying. Without testing on a RED he suggests to underexpose with 2.6 stops to maintain highlights, regardless of what you are shooting. That is a very bad idea. Underexposing on RED will give you a lot of noise and noise on Red is not nice film grain but digital blotchy noise.

My recipe for good RED images: in low contrast situations you expose to the right, which means you expose as high as possible without blowing out highlights. In RedCine you then lower the exposure to something that more resembles the actual situation or something you like.

In high contrast situations you have to choose between noise in the shadows or blown-out highlights, most likely it will be something in-between. But better is it to reduce contrast in the scene: put something in front of that window so it doesn't blow out. Forget about middle gray and percentages, make your images look good in post.
 
Hi David,

A good histogram is a good histogram, either for film out, rec 709 or digital cinema compliance. There is no reason to expose differently, otherwise you know that you will have strong oversampling eg. PAL/NTSC out which will hide noise much better than 1080p for instance and be more forgiving. 4K therefore with no oversampling at all is highly prone to noise.

In this regard I am with you. For exposure it's important to know for wich format you are shooting.

Hans

(Do you have German realtives? Just curious...)
 
No. Signal is signal. The transfer guys get all types of digital, remember some of the footage we've been looking at in theatres, a lot of it off a Canon XL-1.

If you shoot like crap and call it a "style" well, then I guess you're coverd cause it will look like crap on film too! :)

But...

If you're stuff is beautiful, and you shot it on a digital medium, a little post work prepping it for film will still make it look wonderful. The techniques are in the hundreds, but the bottom line is the same for almost all recordings, "your best quality will be as good as your worst shot".

Don't get hung up on "printing to film" shoot the best movie you can with what you have. The tech stuff is nice, but remember, if someone is willing to pony up the kind of dollars to print your video to film, this means it's going to a theatre run, and this means the look of your picture is only a part of the overall consideration. They are doing it because they think you have a wonderful, PROFIT GENERATING movie.

We all love to think "my movie is going to be in 2,500 theatres". But the truth is, while the odds of that are better than winning the lottery, they don't FEEL that way. :) My advice is: tell your DP, "We're shooting on RED, so push RED to make the best picture you can, if it goes further than we're expecting, then we'll deal with that then".

Jay

PS: Of course, if your picture has a $50mil budget and has Jessica Alba's first topless scene... Then expecting a theatre run would be a different story! Then again, for that kind of gig... I think I might shoot film!
 
Big T:
having craft does not preclude sensitivity to content's value. Craft and content prosper in each others company. As a filmmaker, you damned well better have a firm grip on craft/technique. The world is full of people with sound ideas, but so few know how to realize them. They lack the craft. We all know that "latitude" won't save a fuzzy concept; but "latitude" will enrich a strong one. This goes as much for super 8 as it does for digital acquisition....
 
NateWeaver said:
One way to build underexposure into your image without a LUT is to rate the camera at an ASA above 320. Do that and you can place skintones, etc where they look good on the monitor and still have highlights to recover later.

Of course this all happens at the expense of the noise floor.
Click to expand...

I'm getting lost here. how do you "rate" the Red or any camera above or below it's standard setting, or..what does the term "rate" mean. Sorry for the nube questions.
 
Jay A. Kelley said:
No. Signal is signal. The transfer guys get all types of digital, remember some of the footage we've been looking at in theatres, a lot of it off a Canon XL-1.

If you shoot like crap and call it a "style" well, then I guess you're coverd cause it will look like crap on film too! :)

But...

If you're stuff is beautiful, and you shot it on a digital medium, a little post work prepping it for film will still make it look wonderful. The techniques are in the hundreds, but the bottom line is the same for almost all recordings, "your best quality will be as good as your worst shot".

Don't get hung up on "printing to film" shoot the best movie you can with what you have. The tech stuff is nice, but remember, if someone is willing to pony up the kind of dollars to print your video to film, this means it's going to a theatre run, and this means the look of your picture is only a part of the overall consideration. They are doing it because they think you have a wonderful, PROFIT GENERATING movie.

We all love to think "my movie is going to be in 2,500 theatres". But the truth is, while the odds of that are better than winning the lottery, they don't FEEL that way. :) My advice is: tell your DP, "We're shooting on RED, so push RED to make the best picture you can, if it goes further than we're expecting, then we'll deal with that then".

Jay

PS: Of course, if your picture has a $50mil budget and has Jessica Alba's first topless scene... Then expecting a theatre run would be a different story! Then again, for that kind of gig... I think I might shoot film!
Click to expand...

Thought she already did the first topless scene in Sleeping Dictionary - which is a decent film, but for some reason was buried.
 
dVonAllmen said:
Here's a question:

When every theater has switched to digital projection does shooting underexposed to allow for the headroom of film become pointless?

More importantly, does it in fact hurt your digital theatrical "print" because you've introduced more noise than was needed?
Click to expand...

You're not underexposing for film's sake -- the film you transfer to (usually I.N. stock) can handle more dynamic range than a digital camera can deliver -- you're underexposing because you are trying to compensate for digital camera's lack of overexposure latitude. If you don't mind the "clippy" look that many digital cameras deliver in the highlights, then you don't need to worry about it. People are attempting to get close to the wider dynamic range of film because (1) it looks more natural; and (2) it adds more flexibility in color-correction and more tolerance for exposure mistakes.
 
zeke said:
I'm getting lost here. how do you "rate" the Red or any camera above or below it's standard setting, or..what does the term "rate" mean. Sorry for the nube questions.
Click to expand...

You simply build in steps of over, or underexposure by changing the ASA value in the camera. The RED is rated to be equivalent to 320 ASA, so if you dial the ASA down, you build in overexposure and underexposure if you dial it up past 320.
 
Film Ylem said:
You simply build in steps of over, or underexposure by changing the ASA value in the camera. The RED is rated to be equivalent to 320 ASA, so if you dial the ASA down, you build in overexposure and underexposure if you dial it up past 320.
Click to expand...

If you change ASA in camera you simply change the LUT of the monitor-out but not the exposure of the recorded RAW file. It stays at roughly 320 ASA.

Hans
 
This is all very subjective, too, depending on your approach. If you "underexpose" to avoid "overexposure" then you have in fact exposed correctly: "Underexposure" is just that, underexposure! Once you become familiar with your equipment's abilities, in this case exposure latitude, it should be easy enough to place values where you want them for each unique situation rather than just dialing up the "ASA" to reduce your exposures across the board. If the camera rating does not match your taste/requirements then the camera rating is not optimum. Change it to suit. There are so many ways to skin this cat.
 
I'm with David M on this one. Its all fine a good to just go out and shoot to make something look beautiful. The problem is the only way to monitor what you are shooting right now is with a Rec709 output. That doesn't help you if you are shooting something beautiful that will be going to film out.

Last week I shot some simple followup Red test footage for Stu to see just how far down we can push 18% gray to preserve highlights and have reasonable flesh-tones (noise wise) when they are brought back up. Stu is still working on his analysis so I cant speak for him, but in my looking at the footage, if you underexpose a face by more than 1.5 stops to preserve highlight detail, you will be sorry. And really 1 stop (plus the .4 stop headroom in the codec) is safer.

I shot the exposure tests in both Redcode28 and Redcode36. I didn't see much gain in noise floor with Redcode36. I'm sure it's there, but unless I'm missing something the gain seem pretty incremental and subtle.

Paul
 
Bill Anderson said:
it should be easy enough to place values where you want them for each unique situation rather than just dialing up the "ASA" to reduce your exposures across the board.
Click to expand...

This is a point of confusion that I think can get people in trouble. My understanding is the Red camera has a sensitivity curve which maps neatly to 320ASA. If you make exposure decisions using that ASA rating you will be in alignment with what is being recorded Raw. If you change the camera's ASA rating you are not changing what is being recorded Raw, you are changing meta-data. In otherwords, the same clipped highlights exist in the signal.

To preserve highlights, you need to make a change to the optical path, not the camera's metadata. In other words, reduce iris 1 stop, not change the metadata ASA value to 640.

Paul
 
Flat is where I'm at

Flat is where I'm at

There is a much longer explanation of why I chose this route with the RedOne but here's the short version-

Protect the highlights (see previous remarks by David and others concerning digital clipping) and light for the shadows. This approach can lead to a flat image in acquisition but I accept that since I can so easily curve the "snap" back in later. The core advantages of this approach are:

1) Skin tones are at or only slightly below ideal
2) By getting more level in the shadows there is less noise and I can easily crush them to taste in the grade.
3) By managing the highlights I avoid any harshness or "video-ee" edges typical of clipping. I also am careful of the top end since there is no effective way to fix clipping in post, though it can be hidden a bit.

Biggest disadvantages:

1) DPs and gaffers often balk at the flat look on the set monitors.
2) It typically requires a bigger lighting package.

YMMV, just my take.
 
I'm with Mr Mullen on this too. But, Paul, if I "underexpose" anything I'm generally sorry. I know this might seem like splitting hairs, but what you're doing is not "underexposing" but is reducing exposure to compensate for......
Just as you might increase the exposure to facilitate another feel. I don't have a RED but I have no difficulty exposing accurately for RAW data- because at some point in the workflow the data is no longer RAW and (has to) emulate the previsualized image, if you've planned for it. We can all screw up from time to time, but that's another story.

Also, RAW or otherwise, you will alter the data with increase or decreases of "ASA" values as certain as if you increased or decreased the shutter speed or fstop.
This method is not new, (it was often adopted by film users to compenstae for other variables) it's just a wee bit more popular now because of the narrow margin of error of digital acquisition. We can retrieve data from the lower values....
Unless I've missed some other, more unique reason for all of this.
Mr.Mullen?
 
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