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Grading from rMBP HDMI out

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Matt W.

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I'm buying a Dreamcolor for grading (deciding between first and second generation) and its HDMI port only allows for use of the calibration engine when it receives RGB progressive.

The black magic cards (other than the 4k ultra studio, which is $1k) only output YUV, whereas most HDMI ports output both YUV and HDMI.

Apple's built in rMBP HDMI port outputs YUV by default but can be tricked into outputting RGB through software patches and a simple HDMI to DVI adapters.

But is its image "true" enough for grading? Or is it doing weird stuff (warming up the image, etc.) to look "nice" on a TV.

Can I use the rMBP's HDMI port for grading? Or is an interface totally necessary?
 
Great question Matt. It used to be that only purpose built interfaces were appropriate for grading, and IMO that is still the case. That said, as the gap between what can be done via a direct connection vs a "proper" solution narrows, the budget minded content creator has to at least consider what you propose.

FWIW, I am a big advocate of getting the viewing environment well controlled or most of the variances you're concerned with will be secondary issues. Just my 2 cents...

Cheers - #19
 
It's quite frustrating that black magic only offers YUV from its devices. While I'm worried about what kind of trickery Apple's HDMI output does (I sort of assume it bakes in inaccurate color because it just would be very Apple for them to do that), it does delivery RGB (when convinced to) and I figure calibrating properly from the built in HDMI output would cancel out any weirdness.

Should there be any difference between the HDMI signal out for he rMBP and the HDMI signal out from an interface?

I've heard not to trust the signal delivered via Apple's outputs for FCP7/Color/etc.
 
Or would the AJA IO XT work?
 
You only get 8bit output from the onboard HDMI because it only runs through the OSX GDI as if it's just another desktop display. It will output either YUV or RGB, easiest way to "trick" it to do RGB is through EDID management. In other words, if you use a modded EDID through a device like the Gefen HDMI Detective where it represents the display as only supporting RGB, then it will send out RGB. YUV is the default and preferred color transport for HDMI, though. AFAIK, BMD cards like the DeckLink Extreme, etc.. will output either.

Your best bet is to go with an AJA or BMD I/O solution that will support proper 10 or 12 bit output via the HDMI and pair it with a display that can both take that form of x.v. or HDMI "Deep Color" input and also display it with some degree of reliability.

I wouldn't concern yourself so much with the YUV vs. RGB aspect of this. The HDMI output on the nMP or rMBP can be calibrated with third-party software and ColorSync profiles in addition to whatever calibration or adjustment settings are available on your display. It's OK for grading if you take the time to set it up right. However, due to the way it operates, I would prefer a proper monitoring card to facilitate proper frame rate and buffered playback, expanded color space and other options you get with such a device.

Something as simple as the AJA T-Tap can get you 10/ 12bit output via HDMI or 3G SDI and it's under $200. Used DeckLink HD cards can be had for under $200. New ones are not too pricey either. But in order to decide on your output solution, you need to see which one will work with most or all of your software. If you want to run Resolve, you're locked into a BlackMagic solution, for example.
 
Eric Bowen said:
https://www.aja.com/en/products/t-tap#techspecs - should work for what you want.



The output from the display adapter/GPU can be calibrated the same as any output from an I/O device. The difference is just in the default output and icc profile setup. I would suggest looking at this if you are really wanting to calibrate the onboard output.

http://www.xrite.com/i1display-pro
Click to expand...

I talked with AJA and they said that is not the right unit for the job. The IO XT is the lowest end box that will work for my needs. Maybe I'll save up.

I've decided to go with the first-gen Dream Color over the second gen one as it appears to have a superior panel. Work from the HDMI out on the laptop until I have a job that can pay for the Aja. Thanks!
 
Jeff Kilgroe said:
You only get 8bit output from the onboard HDMI because it only runs through the OSX GDI as if it's just another desktop display. It will output either YUV or RGB, easiest way to "trick" it to do RGB is through EDID management. In other words, if you use a modded EDID through a device like the Gefen HDMI Detective where it represents the display as only supporting RGB, then it will send out RGB. YUV is the default and preferred color transport for HDMI, though. AFAIK, BMD cards like the DeckLink Extreme, etc.. will output either.

Your best bet is to go with an AJA or BMD I/O solution that will support proper 10 or 12 bit output via the HDMI and pair it with a display that can both take that form of x.v. or HDMI "Deep Color" input and also display it with some degree of reliability.

I wouldn't concern yourself so much with the YUV vs. RGB aspect of this. The HDMI output on the nMP or rMBP can be calibrated with third-party software and ColorSync profiles in addition to whatever calibration or adjustment settings are available on your display. It's OK for grading if you take the time to set it up right. However, due to the way it operates, I would prefer a proper monitoring card to facilitate proper frame rate and buffered playback, expanded color space and other options you get with such a device.

Something as simple as the AJA T-Tap can get you 10/ 12bit output via HDMI or 3G SDI and it's under $200. Used DeckLink HD cards can be had for under $200. New ones are not too pricey either. But in order to decide on your output solution, you need to see which one will work with most or all of your software. If you want to run Resolve, you're locked into a BlackMagic solution, for example.
Click to expand...

I talked with AJA and Black Magic and AJA said the T Tap is not appropriate for grading and Black Magic says only their 4k device ($1,000) transports RGB.

Honestly, if I can grade acceptably well with my built in HDMI port (in Resolve or Color, I generally use color). I'm happy.

My set up will be:

rMBP, Dream Color 2480zx, HP Calibrating Solution

I want to use a Thunderbolt port for the display when doing photos and vfx. Will calibrate for whatever the default colorspace is.

Then for the HDMI port how do I calibrate that? I found a script to force RGB even without the Gefen hardware.

You can't use AJA interfaces in Resolve? Seems shady...

Honestly my suite of choice is still Apple Color since I grew up in it and it interfaces so nicely with FCP7.
 
Jeff is correct about Davinci and Blackmagic cards. Blackmagic ensures that anyone using Davinci has to buy their I/O cards. So if you need this output for Davinci then your buying a Blackmagic device. I am not surprised Blackmagic limits the HDMi output on their lower end devices. They have done that before. No reason for them not to include RGB output since it's built into the HDMi standard beyond ensuring features are tied to the more expensive hardware.

BTW the question on whether the T-Tap works for grading is subjective as is the question what is best for grading. I was suggesting based on what gives RGB output with the Thunderbolt out. Whether this is ideal for grading is another conversation.
 
Would you consider Apple's built in HDMI interface acceptable for use with Apple Color?

Again, this is NOT for broadcast material (I can go to an office for that) but it is for stuff that I want to be accurate enough that I can work from home and then check it against a higher end system.

I usually use Resolve on larger projects, but at home I just use Color. :)
 
Yes if you calibrate the display correctly and stay in RGB space. The output from an Nvidia GPU can be calibrated to the same output as the I/O cards. There is no difference there other than the starting point. That is why you want to set the profile space for OSX and the colorimeters make that much easier. I/O devices are preset from factory so that work is already done
 
Thank you so much!

Not to seem too needy (but I am since I can't afford a black magic 4k) but once I have my HDMI port outputting RGB and running to the Dream Color, what do I set the output to in system preferences in terms of color space for the HDMI monitor? And after that do I simply calibrate the monitor using the HP probe?
 
You might have to park the HP calibration in the monitor prefs since you are using the HDMI out. Haven't tried your specific config.

AFAIK any monitor being driven by OSX over HDMI is limited to 8 bits. Grading an 8bpc signal is not really professional grading in my book. However, since you have access to a suite where you can view your grades in 10 bit color on a decent calibrated monitor as a reference, its worth a shot. I suggest you do a couple of grades on your home system, then view the same material in the pro suite and see if it looks like you expect. If it's close enough for your needs, rock on.

Cheers - #19
 
Thanks, much appreciated. My low end work lives in 8 bit anyway so I am not too worried. :)

I'm also curious about trying a converter box (component to HDMI or some device with HDMI out and HDMI in like my Ninja 2, but I bet that's just passthrough) and seeing what that gives me. I figure if I calibrate around it the calibration will take it into account? Would love to have 10 bit but that's not a priority at this level. This is not for commercial content, I am just buying a display for commercial compositing work and want to use it for grading, too.
 
Oh forget it I'm getting the z24x and calibrating over BootCamp. It accepts YUV and has better audio output so I can play GT5 on my PS3. :)
 
Matt W. said:
I talked with AJA and Black Magic and AJA said the T Tap is not appropriate for grading and Black Magic says only their 4k device ($1,000) transports RGB.
Click to expand...

Eye of the beholder there... The T-Tap is not optimal for grading, true. However it may still be a step up from the onboard HDMI as it will provide 10/12 bit color and support for proper 24fps or other rates while your desktop displays run at 60Hz.

The BMD DeckLink Extreme products do RGB. Not just the 4K one, not that it matters, the HD / 3D+ one does as well but it's still $800. You would want the 4K one if you buy today as it's the newer, upgraded model from that HD one and technically replaces it. Their UltraStudio 4K also does RGB.

If you ask me, I think you're concerning yourself too much with the whole RGB thing. Don't worry about that aspect of it, it's an intermediate transport between the display interface and your monitor. Just make sure your monitor is calibrated as close to a proper colorspace target, like REC709 as you can get.

Then for the HDMI port how do I calibrate that? I found a script to force RGB even without the Gefen hardware.
Click to expand...

You will need to use a color probe, like the DreamColor to calibrate your monitor and companion software that can create a ColorSync profile or other LUT you can apply to the display. The one downfall to using this approach is that you're still sitting atop 8bit GDI desktop space for color.

You can't use AJA interfaces in Resolve? Seems shady...
Click to expand...

BMD has to sell their hardware somehow I guess. Not unusual for a company's software to only support their hardware. But yeah, if they supported the Kona 3G, Matrox Mojito, or BlueFish 4K cards in Resolve, it would be bye-bye DeckLink for me. The DeckLink 4K (or the HD Extreme cards) are not bad. I just prefer the AJA hardware and software interface.

Honestly my suite of choice is still Apple Color since I grew up in it and it interfaces so nicely with FCP7.
Click to expand...

Apple Color is, or was, very nice. It's a shame they let it die off as they did with Shake. Anyway, I'm still not sure what, if any, of the current I/O cards will work with Color. You may be limited to running out of the system's HDMI anyway, but I think I've already said that.
 
Jeff Kilgroe;1398208If you ask me said:
The 2480zx's HDMI input can only accept RGB.

The RGB component to HDMI boxes (which are like $30 on eBay!) looks cute, but the z24x accepts YUV. So maybe that's the obvious answer, but I hear the panel is a step back...

Anyone used both the 2480zx and the z24x?

Fwiw, the black magic cards do seem to work with Color, but it's not very stable under current OSX builds.

I will forever be a FCP7/Color fan.
Click to expand...
 
So, to be clear, the Decklink 4k going through thunderbolt would work, it's just too expensive, right? (Honest question, because I was thinking of using my rMBP to handle some light grading as well, but only if I can show clients a decent/correct reference).
 
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