Bram Desmet
Forum Replies Created
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[John Fletcher] “I’m really interesting by the CM-170S, but you said the DCI-P3 is beta,”
No, sorry if that was not clear. Both the CM-170W and LM-2461W have a DCI P3 color gamut selection, this has been in the units for quite some time now and is not beta. What is currently in beta is XYZ signal support. Remember, DCI P3 and XYZ signal format are distinct things. The monitor can operate in DCI P3 color gamut whether the signal is RGB, XYZ, or YCbCr.You have been able to monitor RGB signals in DCI P3 since the CM-170W was released in April. Now we can also support XYZ format signals in addition to RGB and YCbCr signals. These can, though they don’t have to be, used in conjunction so you can for example accept an XYZ signal and map it to DCI P3. People have been using our monitors in DCI P3 mode for some time now with RGB signal paths. At least this way they are working in the same color gamut that the deliverable will eventually be seen in. This way the creation of the DCP has less of an ‘unknown’ characteristic to it for the colorist as the data is more or less just being formatted for correct viewing from a Digital Cinema Player and the color gamut of the theatrical devices will be more or less the same as the color gamut the colorist was working in throughout the process. This is in contrast to another popular workflow where people will actually grade in Rec 709 through the entire workflow until creation of the DCP. That type of workflow is more likely to require a final pass on an actual P3 device when all is said and done, but if you don’t have access to a P3 capable device for the majority of your work this can be a perfectly manageable workflow…some people even prefer to do it this way as they work with partners or systems/software they feel offer a very good Rec 709 to DCI transfer.
Bram Desmet
FSI (Flanders Scientific, Inc.)
http://www.FlandersScientific.com -
[John Fletcher] “So… in any grading software, if all output must be on RGB,”
No, that is not correct. You can and equipment does output in XYZ. Moreover, plenty of displays can and do accept XYZ signals. Again, I think you may be a bit confused as to what XYZ means and what devices are supposed to do with it, probably because I am doing a terrible job of explaining it, sorry!The thing about an XYZ formatted signal is that it can be mapped to a variety of color gamuts in a minimally objectionable way and that is largely the point and how it helps to combat obsolescence by not being tied to one specific ‘traditional’ color gamut. Remember, XYZ is actually a distinct way of coding signal information. It is not RGB and it is not YCbCr. It is true that the displays are largely RGB based devices, but this does not mean they cannot accept XYZ signals anymore than it means they cannot accept YCbCr signals, which of course they do. The display simply needs to know that the signal being sent is XYZ and then map that accordingly to the target color space (e.g. DCI P3), but this is not impossible by any means and is done regularly by many devices.
If you have a professional DCP player it is sending out XYZ to a professional digital cinema projector that accepts XYZ. More lower cost flat panel displays will also begin accepting XYZ signals (FSI monitors currently have this as beta support and other high-dollar solutions already do this as well). If you have something like a DVS clipster it can already output XYZ. I strongly suspect that more of the ‘economical’ I/O options will in the future also support XYZ output.
XYZ output is actually not even the most challenging part from what I have been told, the bigger challenge for most manufacturers seems to be 12 bit output (needed for XYZ) as most of the popular I/O cards on the market can only do 10 bit output. You cannot output (for realtime monitoring) in XYZ in Resolve (yet), but it seems like a logical evolution of the software. My purely speculative guess is that this will come almost immediately if/when a BMD card with 12 bit output capabilities is released.
I hope that helps. I am not by any stretch of the imagination the world’s leading authority on DCI and XYZ. I am mostly familiar with it from a display perspective as we have begun to implement support of XYZ and I have gleaned a good bit of information from our engineers as we have rolled this out. I saw your post unanswered and know that can be frustrating so wanted to provide what info I could, but there is a good reason there are companies that specialize purely in DCPs and Digital Cinema workflows because it can be a very esoteric subject.
Bram Desmet
FSI (Flanders Scientific, Inc.)
http://www.FlandersScientific.com -
Another question for you: are you actually going to be grading for digital cinema a majority of the time? Or is there a lot of TV destined work for you as well?
Bram Desmet
FSI (Flanders Scientific, Inc.)
http://www.FlandersScientific.com -
[John Fletcher] “CIE1931, and the XYZ are the same thing or not ?”
No, I think it would be misleading to say they are the same thing. They are closely related.[John Fletcher] “CIE1931 –> XYZ –> DCI-P3 ?”
No, XYZ is not a subset of CIE1931. Again, the Omnitek White Paper should clear this up for you and explain the benefit of encoding values as XYZ.[John Fletcher] “And for monitors, the signal will be better directly with decklink and SDI, or with display port with decklink and HDlink converter “
Always better IMHO to go straight from an SDI output device to an SDI input device (display). I know you are looking for ways ‘around’ using the pro I/O card, but I really see this as having been a greater concern or worthwhile endeavor in the past when I/O cards were relatively expensive. However, professional I/O card options have become so phenomenally inexpensive in the last couple of years that I just think it is the wrong place for professional editors and colorists to try and save money. There are good cards available for a good price and this takes the guess work out of trying to build ‘workaround’ or ‘good enough’ solutions.Also, we need to be careful not to confuse our terms and technology here and to understand what you realistically need for your workflow. If you are color grading in Resolve you are not going to be monitoring an XYZ signal, your output will be RGB. Additionally, you will not be monitoring a 12 bit signal, which would be the bit depth of the signal if monitoring an XYZ signal. What you will be monitoring is a 10 bit RGB signal. Now you can monitor in DCI P3 if you like or in Rec 709 even, but there is going to be a point where your content needs to be transformed into a DCP deliverable. The final DCP will be 12 bit XYZ, but it is important to understand that you will not be working/monitoring in 12 bit XYZ.
There is a nice article here that may also be useful to you: https://www.thefilmbakery.com/blog/creating-a-feature-film-dcp-using-opendcp
Bram Desmet
FSI (Flanders Scientific, Inc.)
http://www.FlandersScientific.com -
[John Fletcher] “it’s necessary to output only the colorspace”
That is not the only purpose of a professional I/O card. I would suggest giving some of the I/O card manufacturers a call and they can illustrate all of the benefits of using a pro I/O card, but when we choose to use a pro I/O card the color space consideration is actually usually the last, though still important, thing we are concerned with as these cards do so much more than that…[John Fletcher] “hrought a regular 10bit display port by example ?”
To the best of my knowledge the Mac OS still does not support 10 bit display port output, it has always been limited to 8 bit in the past. Glad to be corrected if this has recently changed.[John Fletcher] “soon we will use xvYCC, or Rec.2020, or I don’t know what else…”
This I highly doubt and more importantly it ignores the entire premise of the DCI specification with respect to XYZ coding and signal paths.[John Fletcher] “So, why not trying to make a good and definitive colorspace and working environment ?”
They have and this was the specific aim of DCI’s use of XYZ color space and signal coding. They have created a standard that from a color space perspective is specifically geared towards ending this sort of color space obsolescence.[John Fletcher] “Now, the monitor with their huge xvYCC (in example) can allow more than CIE1931 if I understood well… so, why not ?”
No, as you stated yourself a few lines earlier CIE1931 encompasses all colors visible to the human eye. Moreover keep in mind that when we are talking about three-primary RGB display devices the largest color space triangle you can carve out of CIE1931 is always going to be smaller than the entire CIE1931 color space. You will not find a display that can replicate all real world colors visible to the human eye.If you are looking for some good resources to help better illustrate these points I would suggest reading some of Omnitek’s concise white papers on these topics, this one in particular would be a good starting point:
https://www.omnitek.tv/sites/default/files/images/stories/pdfs/support/xyz_colour_space.pdfI have no affiliation with Omnitek other than being a customer, but I think their concise white papers can be more accessible as a quick read than digging through the full DCI spec. The full DCI spec is also well written in my opinion and a good read if you have the time.
Bram Desmet
FSI (Flanders Scientific, Inc.)
http://www.FlandersScientific.com -
Do you have the A/V Output option checked in the Window Menu?
Bram Desmet
FSI (Flanders Scientific, Inc.)
http://www.FlandersScientific.com -
Boris, if you have an issue with a monitor you should really contact us immediately at support@flandersscientific.com, especially if you suspect damage to a new unit as we have a very finite window to make a claim with the shipper. We had to find out second hand from another FSI user that you were asking for my advice on a forum that I do not regularly check. We take photos of every monitor before it ships with both a solid white and grey field and I can confirm that there were no marks as described on this panel when it shipped. Please send the higher quality photo of what you are seeing to support@flandersscientific.com so we can try and determine if this is screen damaged or perhaps something else is going on.
Your unit as it shipped:
Bram Desmet
FSI (Flanders Scientific, Inc.)
http://www.FlandersScientific.com -
While HDMI can carry audio DVI does not so you will only be able to get the video to the monitor with the type of cable Juan linked above. FSI monitors can only pull LTC, VITC1, or VITC2 timecode from the HD/SD-SDI inputs, though I don’t think the HDMI output of any current DSLRs can embed timecode into ancillary data anyway so this is likely a moot point. Come to think of it, I suppose most DSLRs have no true timecode per se, though I am not a DSLR expert by a long shot so I’m happy to be corrected on this point.
Bram Desmet
FSI (Flanders Scientific, Inc.)
http://www.FlandersScientific.com -
Even better, though for most DSLR’s make sure to get the mini-HDMI to DVI, not standard HDMI to DVI cable. But as your link proves, super inexpensive to get a cable like this that will allow you to use the Canon on a monitor with DVI port.
Bram Desmet
FSI (Flanders Scientific, Inc.)
http://www.FlandersScientific.com -
Just as an FYI you can use a really inexpensive HDMI to DVI cable or HDMI to DVI adapter to get video from a camera with HDMI or mini-HDMI out to the DVI port of all FSI monitors. This should only run you somewhere between $5 and $35.
Bram Desmet
FSI (Flanders Scientific, Inc.)
http://www.FlandersScientific.com
