Jump to content

RAW vs ProRes: how much of a difference does it really make?


Bradley Credit

Recommended Posts

So I’ve been shooting on the BMPCC 4K for the last couple months, my first proper cinema camera that I’ve owned. Each project I’ve shot with Blackmagic’s RAW setting which obviously means massive file sizes. I’m planning on playing with ProRes 422 to test on some shoots but was wondering: how much of a difference is there really between the two?

I understand that RAW gives you more ability with things like highlight recovery, changing color temps and ISO in post, etc. But assuming you’re exposing correctly on the day and intentionally shooting with a particular WB, how big of a difference does it really make? ProRes would likely make for an easier post workflow due to file sizes, but I’m curious to hear your thoughts.

  • Like 1
Link to comment
Share on other sites

  • Premium Member

Depends on what you need to do with the footage in post. Probably 80% or 90% of the time, you won't need raw... until you do. I assume you mean you're still recording "film" log gamma though, not "video" (Rec.709) gamma?

  • Upvote 1
Link to comment
Share on other sites

4 hours ago, David Mullen ASC said:

Depends on what you need to do with the footage in post. Probably 80% or 90% of the time, you won't need raw... until you do. I assume you mean you're still recording "film" log gamma though, not "video" (Rec.709) gamma?

Yessir!

Link to comment
Share on other sites

  • Premium Member
2 hours ago, Bradley Credit said:

What are some circumstances where you would need Raw?

Positively need? Not many. I know of one production where they wanted to shoot Alexa, but the distributor wanted 4K. Eventually they agreed that it'd be OK if they shot it raw, to wring every last drop of quality out of the system, but that's more politics than technology.

What it gives you is a (slightly) improved ability to make changes in post, but unless you're making huge mistakes on set it shouldn't really be necessary.

  • Upvote 1
Link to comment
Share on other sites

2 hours ago, Bradley Credit said:

What are some circumstances where you would need Raw?

As stated RAW gives you a bit more flexibility in post to tweak colour and exposure. So for shots with VFX elements that will be composited together RAW is better, e.g green screen shoots, background plates. Same with shots that maybe move from interior to exterior and different lighting conditions RAW gives you more ability to smooth it out etc... 

RAW modes typical give you the edge in overall quality (although not always sometimes highly compressed RAW will look worse the ProRes 4:4:4). So if your project is destined for the big screen or high end TV then you'd shoot RAW.

On the flip side ProRes generally is good enough for a lot of projects Music Videos/Documentaries/Web Videos. The post is simpler and the files are easier to cope with. I've shot a number of project on the BMPCC 4K and so far have never needed to use the RAW mode much on a project. Also a lot of the time (particularly for web work) the 1080p mode is good enough.

Sometimes (particularly for web work and documentaries) I use different file sizes or modes for different shots...e.g RAW 4K would eat too much storage... but on a Prores 1080p project, I might switch to 4K or RAW for a shot that i might need to resize in post or need more latitude. For instance, I might not have a long enough lens for the shot I'm trying to get, so I intend to crop in post. Jumping up to RAW might make sense too squeeze out a bit more quality for those instances. 

 

  • Upvote 1
Link to comment
Share on other sites

5 minutes ago, tom lombard said:

fine point (?) but it's BRAW on the P4k and not RAW.  likely doesn't affect any of these responses but worth remembering when you are talking about the Blackmagic gear with other people.

Sure, but very few cameras shoot uncompressed RAW.

Since RED, the common usage of the term RAW has covered the flavours of compressed RAW and really only means the footage is Bayer encoded, regardless of codec. 

 

Link to comment
Share on other sites

I personally love the Braw and have used the ProRes only on a couple of shoots where we either had to produce ProRes or there was not going to be much post involved.

But we used Braw on all of the narrative stuff and even on music videos.

Link to comment
Share on other sites

I can speak to ARRIRAW vs. ProRes. One time I pixel-peeped a project I had shot in RAW and was able to A/B the same frame in Raw and ProRes4444. The only difference to my eye was in the gradients from midtones to shadows. Raw felt smoother and cleaner - ProRes I could begin to see evidence of compression appearing like stairstepping as light would fall off into shadow. But man, I was at like 300% zoom, pretty ridiculous. I still shoot most everything ProRes on Alexa, but I prefer Raw for darker/moodier projects.

Link to comment
Share on other sites

  • Premium Member

"RAW" is a very loose term, there really isn't a single standard for RAW. Obviously the best formats will be "uncompressed" like Arriraw, but most of the formats like DNG, R3D, Blackmagic Raw, Canon RAW, etc... are all "compressed" which adds another layer to the equation. 

I have never graded Arriraw, but I have graded nearly all of the other formats and I can attest to how good they can and can't be. My favorite is Red Code, it works very well and has a great SDK which enables software and hardware developers to integrate it into their products. It's also very noise free, compared to other RAW formats which can "taint" the image quite a bit depending on bit rate. 

Pro Res is by far the defacto standard these days, as 4444 XQ is full 12 bit 4:4:4 and is a very high bit rate codec. Many shows and feature films are shot with the format due to the Alexa's ability to shoot it. 

Raw does make a difference in post, but if you're a cinematographer who wants what they see in camera to be what comes out the back end, with little to no input ability from the colorist, then Pro Res is the way to go. If you're shooting a modern show and you want all the adjustment in the world in the back end, then you really need to shoot RAW. 
 

  • Upvote 1
Link to comment
Share on other sites

  • Premium Member
1 hour ago, Chris Stiles said:

I can speak to ARRIRAW vs. ProRes. One time I pixel-peeped a project I had shot in RAW and was able to A/B the same frame in Raw and ProRes4444. The only difference to my eye was in the gradients from midtones to shadows. Raw felt smoother and cleaner - ProRes I could begin to see evidence of compression appearing like stairstepping as light would fall off into shadow. But man, I was at like 300% zoom, pretty ridiculous. I still shoot most everything ProRes on Alexa, but I prefer Raw for darker/moodier projects.

Part of that is perhaps because ProRes bakes in some sharpening.

  • Like 1
  • Upvote 1
Link to comment
Share on other sites

On 7/11/2020 at 10:49 PM, Bradley Credit said:

What are some circumstances where you would need Raw?

To be honest, ProRes 4444 XQ is a pretty powerful codec. On narrative projects, I like to severely underexpose the image and then recover it in post for a desired effect (inspired by Jody Lee Lipes and Harry Savides, ASC). One would think that, with such an under exposure digitally, RAW would be essential. But, ProRes 4444 XQ was more than capable.

On the feature film The Watchman's Canoe, I underexposed it by 3 stops and pulled it back up in post. Nearly the entire movie was shot in ProRes4x4XQ with the exception of a few shots that I did in RAW purely because those specific shots needed white balance nuance in the grade (and to be frank, I probably didn't need to do that either). Here are samples: http://www.ajyoungdp.com/articles/narrative/TWC/. Here is a blog post I wrote about the process: http://www.ajyoungdp.com/articles/blog/TWC_underexposure/.

On the short film Ashburn, I underexposed it by 2 stops and pulled it back up. Most shots were done in ProRes4x4XQ, with 25% in ProRes4x4 because we were overloading our data manage with too many cards too quickly. Samples: http://www.ajyoungdp.com/articles/narrative/ashburn/.

Needless to say, RAW wouldn't have improved the images much at all. After really pushing the codec to its limit, ProRes (at least the higher end 4444 XQ) is more than capable of nearly any color grade.

Link to comment
Share on other sites

  • Premium Member

What's the difference between underexposing ProRes by 3-stops and bringing it back up in post versus rating the camera three-stops faster? If you're saving the brightening for post, how do you see a corrected image on set? Or get dailies to be correct?

  • Like 1
Link to comment
Share on other sites

When I tested the underexposure for Watchman's, I did various cocktails of underexposure with ProRes; some like 800ISO 3 under or 6400ISO and eventually the one I landed on was 1600ISO 2 under. The main reason why was the ability to control how the exposure was corrected in post rather than relying on the camera to correct the exposure when deviating from 800ISO. (Other reasons include how the noise level behaved when underexposing and recovering at various ISO's)

Ashburn was a few years later and for that project I learned from the trial/errors of Watchman's color grade and decided that 800ISO 2 under would work for this short film. Ultimately, it was because I wanted to control how to recover the image and the redistribution of the dynamic range. From what I could tell from the earlier tests, the redistribution of the dynamic isn't exactly 1:1 when changing the ISO of the camera.

During testing, I developed a REC709 LUT that corrects the underexposure for on set viewing and used it for Watchman's. I did the same for Ashburn, that LUT specific to that specific underexposure.

Am I crazy, though? Or am I just adding a lot of extra work that changing the ISO already does? haha

Link to comment
Share on other sites

  • Premium Member

Sounds interesting — worth pixel-peeping some comparison tests between letting the camera processing compensate pre-recording versus doing it on some post device post-recording. Either way, your stuff looks great! Like Conrad Hall once said, underexposure is a bit scary...

Link to comment
Share on other sites

Really interesting topic. On Atlanta I believe they are doing something similar, where they rate at 800 ISO but have a LUT that pushes the image a couple stops effectively.

I worked on a show years back that was Alexa rated at 3200 ISO. I liked the look. In theory it should make little to no difference but it sounds like it does.

Link to comment
Share on other sites

1 hour ago, David Mullen ASC said:

Sounds interesting — worth pixel-peeping some comparison tests between letting the camera processing compensate pre-recording versus doing it on some post device post-recording. Either way, your stuff looks great! Like Conrad Hall once said, underexposure is a bit scary...

I think it's worth it. When I can, I'll try to test it out more thoroughly with one of the rental houses in town and share my results. Thank you for the compliment, though!

 

28 minutes ago, M Joel W said:

On Atlanta I believe they are doing something similar, where they rate at 800 ISO but have a LUT that pushes the image a couple stops effectively.

I heard that too! I'd love to learn more about what they did

Link to comment
Share on other sites

Try a test first. it's easy enough.

Shoot Prores 422 HQ, white balance "correctly" then make it clearly wrong. like, 3200 instead of 5600. Then go fixit in post. Same with ISO

Personally, the "easier grading" argument doesn't work for me. if you shoot ProRes HQ there's plenty of data to push around. If you shoot 4444 there's TONS.

I haven't grossly missed my white balance since we had B&W viewfinders. (1995) Sure I've shot at 4000k and later thought, I should have warmed that up some. But that's easy even with Prores LT. hehe

I feel Geoff was right with the politics point. Agency people might think shooting RAW will instantly be noticeable in the final product, so if they want to do that it's fine. Just costs more. 

I think a lot of RAW misconception comes from people coming from photography RAW. If that's the case, they're comparing a JPEG with baked in "look" to RAW, so there is definitely a case for RAW in that situation since it DOES give you more options. 

Link to comment
Share on other sites

One other interesting thing about the Alexa that I find pretty unique is I tried transcoding the 10 bit ProRes 444 Log C I was working with to 8 bit footage and there was no additional banding introduced, even after applying the same LUT to both. if I denoised the image first, of course a lot of banding was introduced.

Most other cameras don't behave this way. The Alexa is a noisy camera, but the texture of the noise feels integrated and organic. Of course it will never look just like film–there is no noise in the highlights, but it's interesting to me.

I also find the EVA1 has a nice noise texture, and I think Dragon was quite good, too. C200 did not impress in the same way.

Link to comment
Share on other sites

3 minutes ago, David Mullen ASC said:

I think ProRes 4444 on the Alexa is 12-bit unless there is a 10-bit option.

XQ is 12 bit, I'm not certain about 4444. I think it's 10 bit, actually, but not sure. 422HQ is 10 bit I'm pretty sure.

Regardless, when I transcode to a lossless 8 bit codec and apply a LUT on top of that, I can't manage to induce banding in the footage. I don't know if it's a lack of in-camera processing or just very good in-camera processing, but Alexa has (to my eye) closer to the tonality of film grain than other digital cameras do.

Link to comment
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
×
×
  • Create New...