FCP Gamma shift

N

naavt

Well-known member
Did anyone already found a workaround for the annoying FCP gamma shift from 1.8 to 2.2?

It's really a pain work on a Mac screen with it shifted to 1.8 just to edit in FCP!

Even more strange is the way that FCP implements gamma! I just don't know how and why it shifts only some footage and not all!!!

Any thoughts will be appreciated on this.

Thanks
 
Set your mac to 1.8 gamma, that's where mac's are supposed to be.

FCP automatically adjusts to 2.2 closer to TV and PC's. Do nor adjust your Mac to 2.2 or FCP will double compensate and things will be way to dark.

If you're monitor is properly calibrated you will be OK and not surprised when you see things on TV or projected in a theater provided you leave your Mac to Mac Gamma (1.8) and let FCP do it's compensation. It's not ideal but it's when you fight it or try to get around it that you will have troubles.

I use the pantone huey pro. About $80 I think. Auto Calibrates your LCD monitor to be as close as possible to true and even adjusts automatically to light changes in the room.
 
Jack Daniel Stanley said:
Set your mac to 1.8 gamma, that's where mac's are supposed to be.

FCP automatically adjusts to 2.2 closer to TV and PC's. Do nor adjust your Mac to 2.2 or FCP will double compensate and things will be way to dark.

If you're monitor is properly calibrated you will be OK and not surprised when you see things on TV or projected in a theater provided you leave your Mac to Mac Gamma (1.8) and let FCP do it's compensation. It's not ideal but it's when you fight it or try to get around it that you will have troubles.

I use the pantone huey pro. About $80 I think. Auto Calibrates your LCD monitor to be as close as possible to true and even adjusts automatically to light changes in the room.
Click to expand...

Normally I have it adjusted to 2.2 because 1.8 is way to bright! I only choose the 1.8 calibration when I work in FCP and ONLY if FCP shift the original gamma!

This is because it doesn't shift gamma every time I work on it! Sometimes I import footage and it doesn't shift, sometimes it does! And that's the weird part of it. I just don't know why it shifts on some footage and not other.

On the other hand, if I adjust the monitor for 1.8 it will be too bright for footage that FCP don't shift gamma! So the perfect solution lies on finding why it shifts some and not all the footage!

Nonetheless, I have a calibrated monitor where I see my CC final adjustments, but it's a pain editing everything on a dark viewer and canvas window.
 
I've been working with FCP through 5 machines and I've never had it do as you are describing, but maybe I'm not working with the files you are. I've used DVC pro HD, Mini DV, Pro Res, and even some avi.

Remember brightness and contrast are adjusted independently of Gamma, I think you may be (possibly) having problems because you are messing with 2.2 at all. Adjust your gamma to Mac Gamma then adjust your brightness and contrast accordingly. Maybe, for example, you are working in 2.2 then switch to 1.8 and start working with FCP.

I really encourage you to leave your machine at 1.8 and adjust your brightness / contrast accordingly.

Other thoughts.
- Maybe it's a CMYK vs. RGB problem?

- You are talking about just in FCP, not once you export and play in QT right? Because there's a
"Enable Final Cut Studio color compatibility" check box there.

I've never had your problems though - maybe a real FCP guru will chime in.
 
FCP assumes that you are working on a 1.8 system and therefore need a gamma adjustment to match the 2.2 broadcast gamma. So FCP automatically adjusts the gamma for certain imported footage. The rules are as follows since FCP 5.1.2:

- Quicktime movies that use Y'CbCr codecs (like Uncompressed, DV, etc.), get no adjustment (assumed to be 2.2 from the start).
- Quicktime movies using RGB codecs (like Animation) and still images (like TIFF) use the setting in Imported Still/RGB Video Gamma (either Source, 1.8, 2.2, 2.22 and Custom). This is kind of new in recent versions (I can't remember when it was added), but in the past, all RGB video codecs got an automatic adjustment of 1.22 (got brighter). Now it's controlled by the same setting as for still images.

Things were more complicated before FCP 5.1.2 where there rules were different and files were also adjusted on export (for example TIFF would get a .824 gamma shift - made darker). This doesn't happen anymore.

You can test the whole thing by creating a gradient in FCP and viewing it with the Waveform Monitor in the Video Scopes:

- Create a grad, view it in the scope and you'll see it as a straight line going diagonally.
- Export the grad as a TIFF. Import the image back into FCP with the Imported Still gamma set to Source. The grad will now appear brighter and the scope will show a bump in the mid tones duo to the applied gamma adjustment of 1.22.
- Now change the gamma for the imported clip (cmd + 9 on the clip in the sequence). Under Format > Gamma change it to 1.8. Nothing will change because any still imported into FCP is assumed to be set to 1.8.
- Now change the gamma to 2.2 and you'll see it revert to the original grad with the same straight slope in the scope.

There's more to this once you start adding Motion (which again assumes that everything coming in is 1.8 and exports everything as 1.8).

Working for TV and need to be sure of your content? Use a broadcast monitor. Only then can you spot all these differences and will you know exactly what will be displayed on a TV.
 
Interesting discussion -- I'm a newbie with only FCE4 but I suspect some kind of gamma issue is making my iDVDs about two f-stops too dark.

Could you tell me how I could check to make sure my Mac Gamma is at 1.8 instead of 2.2? Is that some where in the general system preferences, or in Final Cut application?

My XH-A1 HDV footage looks great when I edit, great when I send to web, but as I said about two f-stops too dark when I burn DVDs.
 
kookooframe, like bluesgeek mentioned you can check it by opening the profile in Display preferences. The red, green and blue tone response curves should all be identical and either set to 1.8 or 2.2 (or close to that).

If you haven't used a hardware monitor calibrator (like a Datacolor Spyder, etc.) or done any other calibration than chances are you are set at 1.8 which is the default for Macs. You can change it by either running a hardware calibrator or calibrating it by eye following the instructions after clicking on the "Calibrate" button (which opens the Display Calibrator) in the Display preferences (under the Color tab). You can go through it without making any monitor changes and just change to 2.2 Television Gamma when it asks you to change the gamma.

My XH-A1 HDV footage looks great when I edit, great when I send to web, but as I said about two f-stops too dark when I burn DVDs.
Click to expand...

On your TV or on your computer?

In general, you can't rely on your monitor to judge color and levels of video during editing that is destined for TV (ex. DVD). They are just different systems and if you want to judge it properly you need to use a broadcast monitor. A cheap alternative is to hook up a small TV to your XH-A1 while it's connected to your computer through Firewire (not sure if you can do that with FCE though). Another option is to burn test DVDs, check them on your TV screen, then try to compensate back in FCE. Through trial and error you'll be able to kind of anticipate (and compensate) how your footage will turn out on TV.

Btw, just because your footage looks good on your computer for web, doesn't mean that it'll look good on someone else's machine. In particular, if you view the same footage on a Windows machine, you might see that it's too dark because Windows uses 2.2 gamma by default.

It's interesting to say the least....
 
thanks Cools n Bluesgeek -- those answers alleviate my perplexity somewhat -- I see it's not just me!

Cools -- a wealth of much appreciated information -- to answer your question, it's on TV that my DVDs look 2-and-a-half f-stops too dark -- they look only about 1 f-stop too dark on (my) computer.

1 f-stop I think I could adjust for. 2 and a half seems a big range where more can go wrong.

But even then -- you color correct for DVD, and then color correct differently for web, and then differently for Mac vs. Windows, -- arghh!

I'll check those display preferences. If I have to tweak before every project on the basis of intended format, so be it. As long as I have an idea of how I can do the tweaking.
 
You must log in or register to reply here.
Back
Top