Hi,
I did some intensive testings and would like to report here the results. It might be usefull for some users. I warm you: it is a little or a lot boring.
We are (no surprise), in a singular situation. Apple ProRes codec has vastly become a standart, but if it is possible to read, import and transcode a ProRes file in windows, it is not possible to export a file in ProRes, this is Apple only. The problem of this Codec between the 2 platform is that it generates a gamma shift, known as the Apple bug.
A "bug" that can cost a lot of headaches, time and money and the company as often does not give a damn when it comes to their interests.
If Avid is known to be too slow to catch-up because they test everything a zillion time before, Apple has become master in reaching to impose good fancy stuff to the pros, even with bugs and only available in their systems. (that reminds the early Bill Gates days init?)
DNxHD is free, works on both platforms, can integrate alpha, compliant with
SMPTE, works extremely well and is becomming step by step the prefered codec in the industry etc...but not as simple, to date Apple ProRes is still a prefered codec for a lot of applications.
Nota: not only the gamma shift can occurs with ProRes, it also does with H.264 in some particular cases.
I did some testings, importing, converting and exporting from windows and compared the results in both platforms. It's deplorable.
Original footage
- Avid: you need to take care of the way you import a file in the bin.
import in RGB, you tell Avid that the color space is not broadcast legal, so it will automatically recalculate the values, wich result in a different gamma, more washed. Curiously, this shift is more or less equal to the difference you will obtain with the ProRes codec.
It is important to precise that this shift could be obtain exactly manually (tried it) putting the gamma values to the legal extremes. So what really does Avid is that it simply consider the broadcast standart.
If you want your footage to not be affected by Avid, you have to tell him to import in 601-709, this basically is telling Avid that your file is fine and does not need any gamma correction.
That is very important.
After-effects-Autodesk etc...
If you import the original footage in After-effects or Autodesk in whatever bits, what those programs read is exactly the same as your original footage. 100% consistency in RGB.
But be carrefull.
If you apply a color correction in After Effects, then export from it in an Apple codec let's say H.264, the result will be absolutly correct to what you did in both platforms.
So as reimporting this footage in Avid in 601-709 mode (for the reasons explained above). 100% consistency there.
Not the same can be said with the use of importing ProRes and work with it or in a transcoding export. That simply does not work with accuracy.
But if you are using Autodesk, apply a correction and export with Apple codec(s), you'll have the gamma shift, except if you export in an uncompressed format wich then keeps the consistency (but then you don't use Apple codecs).
On the other hand, if you export in a Quicktime container using the DNxHD 10 bits codec, you do not have any shift, even reimporting in Avid and re-exporting, in Win or Mac etc...
In other words: DNxHD is the only codec so far in my testings that keeps the visual consistency in all the chain involved, regardless of the platform involved. Exporting any Apple codec from a DNxHD master for delivery also results in 100% accuracy. Or in other other words, Avid did the homeworks, Apple didn't and put the mess on the chain. They want people to buy their computers and softwares, Avid wants people to edit without issues. Big difference.
So, "Houston we have a problem": ProRes is very fashionable and can only be generated from a Mac and not free. This is the word of the gamma surprises from a platform to another.
How the hell do we solve that properly once for awhile??? Because if we could, we simply can ignore the ProRes, but the sad reality is that we can't ignore it. Thank you Apple to bring your fancy, wonderfull, brilliant and personal idea of standardization !
It's like the frenchs (I'm french), they can make the world beleive that they have the best wines so they can sell a very bad Bordeaux twice the price on the marquet and people are thinking they are drinking a top wine...the french label and the apple label are one and the same hoax. It's all about design and brand cool effect perception.
!!! I can't beleive I'm still loosing my time (and I'm not the only one for what I'm seeing on RedUsers, CreativeCow etc...) on those codec surprises while I should be editing and-or shooting.
Look at what kind of D.I.Y solution we have to deal with:
http://blogs.adobe.com/toddkopriva/2009/12/prores-4444-colors-and-gamma-s.html or
http://www.isophia.co.uk/prores-gamma-shift-fix/ etc...
My solution (and some others too): exporting ProRes from Mac if you have to send it to other editing platforms with
YUV settings,
This is because ProRes has a double nature: YUV and RGB
re-imported the clip into Avid with the DNxHD 10 bit codec
(watch out the import setting, anyway Avid is transparent and you'll immediatly notice if you are right)
export to Quicktime with RGB setting. It works!
You need to know absolutly each one of your applications encoding. If I send a ProRes file to Autodesk in YUV, I'm doing things wrong.
or, if possible, always go uncompressed.
or...go to the bar and forget about that mess! That's what I'll do right now.