Andrew Somers
Forum Replies Created
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To answer your other question, BouJou, PF Track, Syntheyes, all allow you to add custom track points.
Andrew Somers
VFX & Title Supervisor
https://www.GeneralTitles.com -
Thank you for the screenshot Pierre,
Well that’s interesting. Looking into this and based on how Adobe has traditionally handled non-color-managed operations, that preference only does the following:
1) Use 2.4 gamma for certain blend operations.
2) Gamma encode linear sources to 2.4 even when color management is off.But I think I can also safely assume that switching the preference between 2.2 and 2.4 will have NO EFFECT on the appearance or rendering of outputs (except perhaps a render to EXR).
Prior to that feature, with color management off, AE would use a gamma encoding for blends (unless “use gamma 1.0 for blends” was checked), and the display data would just be sent to the monitor, which typically would be an sRGB monitor with a ~2.2 gamma.
While I can’t test this I have to assume that if you switch this to “assume 2.4”, the displayed image will not change, and thus if using that same sRGB monitor, you will still be seeing images with a 2.2 display gamma, not 2.4
With color management OFF, you need to physically adjust your monitor to a 2.4 gamma to see 2.4 gamma, regardless of how that preference is set. Also, output modules work the same as if “preserve RGB” was checked with CM ON.
With color management ON, you can simulate different output devices, such as you can emulate a 2.4 gamma display on your standard sRGB 2.2 gamma display. Also, the output module can convert to a different space/gamma unless “preserve RGB” is checked.
If you use AE with color management off AND “blend using gamma 1.0”, then the only thing I expect that preference to do is convert linear material to the selected gamma, which you would previously do by using the Profile Converter effect or Levels with a gamma adjustment.
Andrew Somers
VFX & Title Supervisor
https://www.GeneralTitles.com -
Oh I see what you’re saying Pierre — I rarely use Premiere. But I thought Premiere was not color managed? If it is not, then it would be correct to send the image into a 2.4 gamma calibrated monitor, or to emulate that with a LUT.
I don’t use the newer versions of AE — when you say they added a “working gamma of 2.4”, I assume you mean when colorspace is off/unmanaged? I’ve looked at the new features list, and I don’t see that as an option? What/where is it? Can you post a screenshot, I’m curious what Adobe means here.
Andrew Somers
VFX & Title Supervisor
https://www.GeneralTitles.com -
Hi Pierre,
Jerry’s issue has to do with his workflow and encoders, and if I recall some interpretation settings, and I believe he is using color management.
Pierre said: Although sRGB and rec709 are close enough,
Rec709 and sRGB use identical color primaries and white point. Other than the transfer curve, they are not just “close enough”, the primaries are interchangeably identical (if working in a linearized space, there is no difference in choosing sRGB or Rec709 as far as the working space is concerned — the only difference is in the output module when rendering to a gamma-encoded file format).
Pierre said: gamma 2.2 and gamma 2.4 is not
Just to be pedantic: sRGB (file encoding) is not gamma 2.2, but a parametric curve. Some (badly made) sRGB ICC profiles may use a simple 2.2 gamma curve, but the correct transfer curve is actually a gamma curve of 2.4, offset by a linear section near black, that results in approximating a 2.2 curve. The linearized section is to allow the curve to be inverted using integer math (computationally less expensive than float).
sRGB CURVE
Rec709 is never gamma 2.4,( though there is much confusion on this point.) Rec709 defines the source/file encoding and Rec1886 defines the DISPLAY, and Rec2035 defines the VIEWING environment.
Rec709 is *also* a parametric curve that approximates a 1.9-2.0 gamma curve. Here the linearized section was intended to help with noise in the black areas of camera signals of the day (remember the spec was developed circa 1990, well before digital HDTV emerged).
Rec709 CURVE
But these show the curve as encoded in the signal or file — NOT in the DISPLAY itself. The Rec709 curve is “source referred” and even though the sRGB curve is called “display referred”,NEITHER curve defines the actual display gamma of the monitor in any particular instance.
The sRGB curve for the file encoding is parametric, but the actual monitor spec is a simple gamma 2.2 curve.
Using log intensity in this graph to make it more apparent, note the difference between the sRGB curve (file encoding) and a simple 2.2 gamma curve (Idealized display).
But in addition, displays are very user adjustable. Some even have a control labeled gamma, but most or all have BRIGHTNESS (gain) and CONTRAST (lightness/luminance) – and unless a hardware calibration and profiling is done, they could have been set to an “equivalent” gamma from 2.1 to 2.5 or more.
(Also, remember that legacy CRT displays were typically a gamma of 2.4 — see “Digital Video and HD” by Poynton)
In the case of Rec709, the 1.9~2.0 signal/file gamma is fed into a monitor with an EOTF display gamma of 2.4, per Rec1886. Rec709 defines ONLY the SIGNAL or FILE gamma. Rec1886 defines the MONITOR gamma.
Side Note:
DON’T FORGET THE GAMMA GAIN
Both sRGB and Rec709 have a “system gamma” that increases the gamma by the time it is displayed. For sRGB it’s a power of about 1.1, and it’s a power of about 1.2 for Rec709.Side Side Note:
DON’T FORGET THE ICC PROFILE
If you are working in a color managed system, then the actual physical gamma of the display is less relevant or simply irrelevant. Assuming the display is profiled with a hardware colorimeter, the effective system gamma will be whatever the CMM adjusts it to, based on various settings.Pierre said: Your computer monitor is likely sRGB gamma 2.2 and your TV is likely rec709 gamma 2.4.
The monitor and the TV are likely all over the place. Both have easy to access user controls that can shift the effective or actual gamma all over as a typical user adjusts for “what they like” for any given environment. Unless they are adjusted with hardware (a colorimeter), there is nothing to enforce a 2.2 or 2.4 gamma.
And in fact, unless the monitor is in a calibrated viewing environment (such as Rec2035), then the specified gamma of sRGB (or Rec1886) may in fact be wrong in terms of creating the same perceptual uniformity. In fact the reason for the increased gamma in the system is because the expected viewing environment is dimmer than the environment while the image is being captured with a camera. The brightness of the viewing environment critically changes the perception of the displayed image.
Rec 709 related display and room specs:
Rec 709 FILE/SIGNAL:
Gamma: 1.9~2.0 (parametric curve)
White point: D65Rec 2035 Viewing Environment:
Room Illumination: 10 LUX
Ambient white point: D65
BG to Screen luminance ratio: 10% of screen reference whiteRec 1886 Display Qualities:
Gamma: 2.4
Reference White Luminance: 100 cd/m2 (meaning m squared)
White point: D65sRGB related display and room specs:
sRGB FILE/SIGNAL:
Gamma: ~2.2 (parametric curve)
White point: D65sRGB Viewing Environment:
Room Illumination (Encoding): 64 LUX
Room Illumination (Typical): 200 LUX
Ambient white point: D50
BG to Screen luminance (surround reflectance): 20% of screen reference whitesRGB Display Qualities:
Gamma: 2.2
Reference White Luminance: 80 cd/m2 (meaning m squared)
White point: D65Notice the substantial difference in ambient light for the Rec2035 view environment (modeled after a dark living room) vs the sRGB view environment (modeled after a typical office environment).
The point to this long winded post is simply to indicate the importance that the FILE encoding is NOT intended to be the same as the DISPLAY’S GAMMA, as the overall system gamma is designed to increase the gamma from end to end.
Thus a Rec709 file should never be encoded as gamma 1/2.4, but should be the parametric curve closer to 1/2.0, thoiugh it should be noted that the viewing of the working space SHOULD be setup (such as with a view LUT) to display that system gamma gain.
Andrew Somers
VFX & Title Supervisor
https://www.GeneralTitles.com -
Blaise Said: “Precompose the text… “
LOL beat me by seconds… LOL
Andrew Somers
VFX & Title Supervisor
https://www.GeneralTitles.com -
You CANNOT use many plug-ins/effects directly on layers where/when you are using layer styles (and certain other half-baked layer features).
Either put those effects on an adjustment layer, or pre-comp the “STOP” layer moving all attributes into the precomp.
Then apply the effects/plug-ins onto the precomp layer in the main comp.
Andrew Somers
VFX & Title Supervisor
https://www.GeneralTitles.com -
You can’t pre-comp and zoom in like that — when you pre-comp, you essentially lock the resolution, unless you Collapse Transformations, which breaks what you are doing.
If you want to zoom into the handshake, you have to do it in the handshake comp itself, so that you are affecting the individual vector layers directly.
1) Create a NULL OBJECT
2) Parent all AI layers you want to scale to the null
3) Scale the nullAndrew Somers
VFX & Title Supervisor
https://www.GeneralTitles.com -
Hi James,
FIRST: You can copy/paste layer styles, so if you need to put the same setting on a number of layers, copy one after fixing and then paste on the other layers. Also, if you adjust settings on one, and have multiple selected, they should all update.
ON WORKING AT HALF REZ:
Be careful working at a resolution other than “full”, as many things like plugins, not just styles, can render incorrectly or in unexpected ways.If you want to improve performance while working, use ADAPTIVE RESOLUTION.
On Viewer:
In Prefs, set the limit to the level that works for you:
And for RAM previews, in the RAM Previews panel set a lower resolution, as that is independent of your main view resolution.
Andrew Somers
VFX & Title Supervisor
https://www.GeneralTitles.com -
It’s fast if you have nVidia and CUDA cores — I actually use it for some things, mainly ray traced gold titles.
Andrew Somers
VFX & Title Supervisor
https://www.GeneralTitles.com -
Walter said: Well… it’s worth noting that Animation can be encoded on any platform, and that depending on what you’re doing, an 8-bit RGB intermediate could be superior to a chroma-subsampled Y’CbCr intermediate like ProRes 422, even though it is 10-bit.
Yes, I agree, certainly a color key would be less desirable with a 422 format, but I was thinking more along the lines of ProRes4444 though I see I wasn’t totally clear. And of course I tend to forget the incomplete support for ProRes on windows. Avid’s DNx formats tend to have some weird artifacts that I like to stay away from.
I did have a client once that had problems using ProRes or DNx, and needed the Animation codec with alpha just to make things easier for them.
Andrew Somers
VFX & Title Supervisor
https://www.GeneralTitles.com
