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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 :)

Exposure 101...

Now that you're asking ... i'm always wishing stoplights would be referring to RAW data ... go for it!
That's also because i would be shooting RAW view mode all the time, but clients are asking for RedSpace, so having RAW references when in RedSpace mode would help me alot.
:)
 
Simon Valderrama said:
Now that you're asking ... i'm always wishing stoplights would be referring to RAW data ... go for it!
That's also because i would be shooting RAW view mode all the time, but clients are asking for RedSpace, so having RAW references when in RedSpace mode would help me alot.
:)
Click to expand...

So they do clip out normally when you are in RAW mode?

Jannard said:
The Stop Lights next to the color bar are from the RGB path! Don't let them fool you. Sometimes they are on and you still have detail in the highlights. We are likely to change this in a future build to represent RAW and not the RGB path. Thoughts?
Click to expand...

After reading this again I wonder if I didn't understand it the first time. Is this referring to what I am asking about? If so then I would agree hands down Jim. Sorry I missed it.
I love the idea of working exposure with nothing but the RGB histograms, though false color sounds like an even better zebras function which are always very helpful to me when set to 105% in RGB. Personally it would help me a lot to be able to quickly look at the traffic lights and know what I am getting on the .r3d file! Perhaps this is obvious but more specifically I would love it if the chart represented the full dynamic range capable of being recorded in the 12-bit Red Code RAW file and the values were untouched. It wouldn't hurt if somehow the graphic could be a bit taller. Thank you for considering this. If I understood correctly I really like your idea!
 
this might have been mentioned many times before - my appologies if it did...

since there's talk about changing the traffic lights to show raw info - i would like to take this opportunity to strongly suggest that in a future build the display shows what color space one is shooting on.
in certain situations its hard to determine whether it is showing raw, redspace or rec709. as many of us (i guess) have assigned a user button to show raw and flip back and forth quickly in order to check for exposure, a display hint would help A LOT.

remotely related to the traffic light topic i know - but there you go...
 
Jeff Kilgroe said:
Yes! If the stop lights can be made to represent RAW color channels and not RGB derivatives, that would be excellent. The camera records RAW, so all meters should be representative of these RAW values wherever applicable and/or possible.
Click to expand...

Exactly! :beer:

I guess I also like the idea of limiting the colors/areas in the false color to clipped, bottom 5%, top 5% and clipped at the top end. I guess a fifth level would be very useful too, and perhaps making this last level user definable would make almost everyone happy... short of making the whole thing fully customizable, which might in turn create confusion when going from camera to camera without proper prep, or with prep but having forgotten to set this function the way you like it.
 
Christian is right - a color space indicator would be very nice - especially if you show REDspace to clients but expose in RAW using the "view RAW" sometimes you can get confused or forget to press the button again. - should be simple to remember but its not when you pull 16 hour days---

I think its a great post you started here JIM, and the shadow zebras sounds brilliant! never thought of that...

Education is the key... the consensus amongst the DOP´s I know here in Denmark is that you have the be extremely accurate when setting exposure shooting RED. Several say its the hardest camera to work with because of this.
They are very concerned about noise.. and Im talking about some of the big boys here in Europe...

Although RED has a certain amount of DR, it seems that it is not equally divided meaning you definately have more detail in the shadows that you can pull out, than in the hight light - but what excately is the ratio for acceptable noise levels? 4 stops under 2 stops over? 2 under - 2 over?
 
Hi Jim, Stuart, all others,


Jannard said:
[..]
There is plenty of DR in a RED ONE to make great images... many have proven that. But the range is limited enough that you can easily miss the window if you are not careful. Let's recap a very simplistic starting point for exposure to keep you out of trouble.

[..]
The Stop Lights next to the color bar are from the RGB path! Don't let them fool you. Sometimes they are on and you still have detail in the highlights. We are likely to change this in a future build to represent RAW and not the RGB path. Thoughts?
[..]
If anyone cares to add... please do.

Jim
Click to expand...


You asked for it, so here we go!

As being the first german RED user I and my collegues had the chance and opportunity to give quite a bunch of demos and instruction sessions to camera operators, including events at Berlinale, edit*, diverse film schools etc.

In all these session I explained them that the most important advantage from RED ONE (over most existing electronic cameras) is that it can store its high dynamic range into the saved image data.

Other cameras may still be good in dynamic range, but they can rarely store it, instead these do internal preprocessing to get the bits down, which means loosing detail.

So, as you also correctly pointed out, the important point is to keep the exposure within the limits and still have a wide dynamic range covered, for maximum fidelity in post & grading lateron.

There are many options inside the RED ONE to measure this or that, to interpret that data this or that way. I love to have them all, but only a few I find to be essential, so here is my pray of using a RED ONE:


1. Use the RAW histogram and keep an eye on NOT over- or underexposing it.


RED is a RAW camera, so all you have to take care of is to not over- or underexpose your takes. The best way to control this IS the RAW histogram and a RAW exposure ample.

So PLEASE - yes - change this RGB amples to RAW amples!


We asked for this many times in the past, and it makes just sense. The way it is right now is more than confusing. So please change!

In a perfect world the RAW histogram would look a bit like Ayers Rock, raising just short after pure black, falling just before pure white.

In reality a histogram clearly depends on the scene, but often this "Ayers Rock idea" is pretty close.

Adjusting aperture is directly visible as linear scaling in RAW histogram. Nice to see, nice to understand. Simple to use. Very predictable. Hands down, not confusing!


2. Forget ALL the ASA/ISO manipulated outputs.

Thats for customers for "video village" applications. Don't care if it doesn't look perfect as long as you are sure the exposure is right (-> RAW).

I am not talking in the sense of videographers, but in the sense of cinematographers. If one needs to shoot RED for instant delivery via SDI output for on-air, well, forget about me and my saying completely :)...


3. Take care of your framing. Use the RAW monochrome mode if possible, to avoid being disturbed by color interpretations of RAW mode, and to see a brilliant sharpness.

Make use of the visible overscan, act like a film DOP and have an eye for that microphone hanging down from top, that light entering from the left or right etc. Understand that and what its being used for. You can't imagine how many traditional "video camera filmers" have no idea of this - many "ahh" and "ohh" to hear...


4. Use edge highlighting for easy control over focal range.


Thats why I also recommend the monochrome mode for framing. Color is the job of the colorist, lateron. We strictly prefer grading "sensor wise", ie. mostly ignoring the ASA/ISO alterations and keep the data as straight "RAW" as possible. This is a strict film workflow. With film I would have had a film scanner sending me simply "full range DPX files". That is what I want. That is what RED ONE makes so wonderful (IMHO).

ONE BIG WISH:
Being weak on red/green I have BIG issues seeing that red outline for the "sharp" edges. Thats honestly a big pain for me and all those having the same issue (~4% of men?). So all I want is to have the chance to select the color for this outline, preferably blue in my personal case.


Another wish could be to make even the edges thicker, but I think adjustable color will do.


5. Use the sharpness focus overlay for easier sharpness control in the field.

One whish here:
Could the focus overlay mode be changed so that we can still scroll the line interactively with the cursor WHILE displaying the overlay?
Right now this feels rather non-intuitive. I see no reason why moving the line with the cursor would be any different than in normal focus assist mode.

When my wish for #4 is made come true, I might forget step 5 completely, but its a nice work around. And be aware, I met quite a bunch of camera men who suffer of the same more or less strong color blindness issues that I suffer from. Once I let my cat out the bag, the outing begins... I won't add names here (hey, that could directly affect them job wise - understandingly), but be sure, you would be suprised who all...


I should add that I am technical supervisor at Magna Mana Production - a post production company with offices in Frankfurt am Main, Berlin and daughter companies in Munich and Berlin, so my background is not primarily shooting the material on my own, BUT knowing the best workflows in post. So what I recommend here aims at meeting the highest quality output standarts in post, uncompromised. That requrires the shooters to deliver the best dynamic range possible.

Thanks for listening,
Axel
 
I would also like to know where the noise floor begins. 4 stops under?
And does false color read raw perfectly now?
Thanks
 
roberto, think of 18% as a benchmark.

lens, film sensitivity and lab are three factors that need an "absolute term" to do their math correctly.
that absolute term is (as it's usually the case), an average. 18% gray revers to a surface that reflects only 18% of the light hitting it. thus appearing light gray. (white reflects 100%, black 0%).

the way it was taught me is that "they" analyzed hundreds of pictures and took their average reflectivity. that average turned out to be 18% gray. that story might in fact be wrong, but it's a nice way to think of it nevertheless...

now lens manufacturers, emulsion developers and labs where able to agree on a constant. like: "if you want this surface to be exactly THAT gray, and your using this asa stock, you need to use this t-stop to have the lab give you the result you're looking for.

light meters use the same principle. all a incident light meter does is being a 18% graycard, telling you to expose for a certain t-stop, if you want that certain gray (represented by the light meter) to turn out 18%.
 
Processing poorly (subjective) exposed low-light tungsten RAW footage in RC or RA at 3200,
often produces more noise than processing at 5000K and colour correcting.
This should not be the case.

In my opinion, it's caused the most heart ache for new shooters. Its like you under-expose in post; a sort-of blue channel timing issue.
I'd like to know what is going on in the software here. Blue gain obviously, but could a different approach be used? Are there consequences?

We have discussed using 80 series filters, CTB for lights, opening up (if possible).
But if I was shooting "Barry Lyndon" tomorrow (1500-2200K sources for instance), I think I would develop at 5k and CC.
I don't think this should be the case.
 
In most cases I shoot to the right by using the raw view and zebras. I would prefer an option that the histograms and the traffic lights are always showing the raw mode whatever is the view setting. It would also be useful to have some scale above or below the histograms showing at one glance how many stops "the peaks of the R, G and B mountains" are below clipping.
 
One thing that has helped me a lot has been playing around with my footage in RedAlert/Redcine/Color and seeing how a particular lighting setup reacts when I set the LUT a certain way. By spending more time in post, you learn to figure out your limits in production.
 
Jannard said:
Lots to chew on... we are listening.

Jim
Click to expand...

Many thanks.

I also would like to propose complete control for separate viewing methods on individual outputs for EPIC and Scarlet (as I don't think this is possible for RED ONE).

What I mean is that the Operator / AC could be viewing RAW or False Color Mode, while a separate monitor output was able to provide video village with REDSpace or perhaps a LUT uploaded from REDCINE or RED Alert!.

There have been many times where leaving False Color mode on could be helpful for the AC not but desired on the client's monitor.

The main idea moving forward is each output can be set absolutely individually. Every menu option for overlays, exposure meters, color space modes - each assignable on an individual bases.

For instance, modes available on each output through menu choices could be:

1) Default - This mode depends on the type of output, but is the default when the camera is booted.
2) Custom - This mode would allow each output to be set individually (example: False Color on LCD (RAW), Focus Assist on EVF (RAW), Timecode and REDSpace LUT on Preview Out) and it would be save/loadable with the Camera Settings via SD Card). This mode would automatically be enabled as soon as a setting on that output is changed. (If a button on the EVF is pressed for focus assist, the mode changes from Default to Custom).
3) Slave - This mode would allow the user to "lock" the current output to another previously set output. (example: RED LCD is already set to REDSpace with RGB Histogram and 16:9 overlay. Simply select Slave, and then cycle through the available existing output options (EVF, LCD, Preview, HDMI, etc.) to link it to. (like a copy and paste of output settings).
4) Reset All - This would reset all outputs to factory defaults. (and have an Undo ability)

If this is something that is possible with EPIC and Scarlet (or even just the S35 and up models) and anyone is interested, I could take a stab at making a mock-up Camera menu tree for it.

Thoughts?
 
Casey Green said:
Many thanks.

There have been many times where leaving False Color mode on could be helpful for the AC not but desired on the client's monitor.
Click to expand...

Yes, but it does get a reaction from the client "oh, cool. It's like Predator or something".

I too am hoping there is a way with the new cameras to spilt different views/modes to multiple outputs. A lot of processing to get that done though.
 
Well,

All meters to raw yes but.... it's great to know you have that highlight detail in situations you can't control, like sunlit exteriors but.... it's better to light for a particular LUT in be within its confines when you go into color correction. Retrieving highlights isn't always easy or pleasing even in a raw CCer like Scratch.

So, all meters to RAW yes... but... a clear indication of where the exposure lies with regards to the current LUT. On a histogram I can imagine vertical bars that show where clipping will occur in the processed image for example. On the stop lights maybe an open circle for clipping the LUT and a closed one for clipping the raw.

IBloom
 
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