Yup, I think that coarse mask is way better!
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One of the things I’ve noticed about a few presets and shaders is that when removing the gamma of original core image some are using 2.2 and some are using 2.4. Is there a ‘correct’ value here?
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BT 1886 is supposed to represent the gamma curve of CRT tvs.
BT 1886 is similar to 2.4.
Since the standard gamma for PCs is SRGB and it approximates 2.2, most people want their 2.2 monitor to look like it is 2.4.
BT.1886 is not valuable just because it is a standard, however. It offers several clear advantages over previous practice. First, BT.1886 more closely mimics the behavior of CRTs than previous power functions, and therefore better ensures consistent viewing on different display technologies.
per industry leaders portrait displays.
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@HyperspaceMadness @c9f5fdda06 (tagging @Dogway and @Nesguy also as they might find the article of value also)
From what I understand CRT gamma is supposed to be 2.2. Displaymate has a very interesting article about CRT versus other display technologies, with some valuable measurements also.
http://www.displaymate.com/ShootOut_Part_1.htm
Gamma measurement of the Sony monitor is in part 2. It’s measured as the “ideal” value of 2.2.
Interesting btw how they relabel some analog controls:
The Functional Names of User Controls
In Parts I and II we have discussed the functionality and confusing names given to display controls. Below is a summary.
Brightness Control:
It doesn’t control brightness, it actually controls the display’s black-level. Its true functional name is: Black-Level Control . Note: on many LCD displays the Brightness Control does instead control the intensity of the backlight, so its name is actually functionally correct there. This variation, of course, adds to the overall level of control confusion.
Contrast Control:
It doesn’t control the display’s contrast because it proportionally increases or decreases the entire gray-scale, so none of the brightness ratios change. Technically it varies the video gain. It actually controls the display’s overall brightness. Its true functional name is: Brightness Control.
Gamma Control:
If it really controls the Gamma, which is the logarithmic slope of the gray-scale, the functional name for this control is: Contrast Control . Every display should have one in order to allow the image to be properly adjusted. Control name confusion is one reason why almost all displays and projectors are missing this essential control - most people think they already have a Contrast Control due to the mislabeling of the functional Brightness Control.
After 75 years of misuse it’s not too likely that this will be straightened out any time soon, but we thought you might just want to know how things should have been named.
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Thanks for the call, probably you already read my post here. There are many names for the same thing one of those I find quite interesting is the luma range (or dynamic range 
) , in avisynth we call it TV/PC range, in broadcasting it’s called Studio/Full Swing or even Broadcast Safe or SMPTE legal, nvidia calls it full/limited range, papers call it quantization, or sometimes compression or expansion. It’s necessary to know all of them to interpret the functions properly.
In color grading, black level and brightness are called Lift and Gain respectively or as a popular grading forum name LiftGammaGain.
In respect to gamma, the specification is 2.22 but I think consumer sets were adjusted more to 2.40 with a cooler probably D75 temperature. But it would be nice to find measurements of non calibrated CRT TV sets. As @hunterk pointed out in this post it might be possible that developers designed the palettes against a consumer calibrated set and not standard ones.
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Thanks! I think our tastes have been converging a bit lately, lol. I find very little to object to in that second shot. Scanlines could be a bit more pronounced over highlights for my taste; I think that would add even more pop to highlights (the black adjacent to the highlights increases the contrast). I don’t really care for curvature but that has more to do with what it looks like in motion; in a still image it’s fine.
Yeah, the mask definitely adds depth. Adding dark lines/dots/etc to the image is going to increase depth, dynamic range and contrast at the expense of brightness. The key is finding the right balance between depth and brightness while avoiding clipping. The final touch is to add a bit of bloom, which spices things up a bit and keeps things bright with normal backlight settings. With Dogway’s grading shader you can expand the dynamic range even further (seriously, check it out if you haven’t yet).
I’m guessing this is Easymode halation? I’d like to try that mask but I slightly prefer gaussian blur to fixed algorithms. They both have pros/cons, though.
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Looks great with the brightness maxed out. How’s the motion blur with the built-in BFI? Some displays handle this better than others.
What shader is that?
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BFI with my LG C9 is great! The shader is guest’s, of course . The ability to change the gamut and CRT profile are the reasons why I mostly use his. In this case I did a conversion from DCI-P3 to srgb and monitor profile 2.
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The C9 is a great gaming display, and the only OLED I recommend getting at this point. Has around 6ms input lag at 120fps, IIRC.
I’m guessing there’s still not enough brightness for full-strength masks, though. Which mask is that? 5-7 do weird things to gamma that I don’t like. I think the guest-dr-venom slotmask is probably the best option for 4K (of the guest-dr-venom masks) because it has parameters to adjust the size and width of the pattern. There are also some aperture grille variants not included with guest-dr-venom that work well at 4K, check out the mask shader snippet from hunterk for those.
Also check out Dogway’s grading shader, can’t say enough good things about it.
When you consider that most tv is calibrated to 100 nits, 80% OLED achieves that and 100% is 120 nits which is very comfortable. With all of the bells and whistles it is 100 nits. I use mask type 7. It’s completely bright and playable in a completely dark room.
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It’s not a problem of brightness per se. Sorry to do this to you, but that mask results in banding / posterization at the low end. Masks 5-7 all do this. Needless to say, this is really not good for objective picture quality, but if you’re happy with it then that’s all that matters. I’d check out the other masks I mentioned as you’ll get better/more accurate results with those.
Mask 7:
Mask 3:
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My calibrator arrived!! I wanted to test a few things brightness wise. You say that a CRT with masks (scanlines or not?) should measure 120nits? is that ok?
I will try to measure a few masks, intensities and compensation for HDTV back light settings. By the way, I should check if there’s a BFI option on my TV (or it’s just set on Retroarch right?) it’s a mid tier Samsung from 4 years ago but I think it would mess with my modelines so…
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A higher-end CRT with or without scanlines will have a max of about 120nits. When in double-strike/240p mode, more voltage is applied to each line so the brightness is the same.
For BFI, just set the display to 120Hz and enable BFI in RA and you should be good to go (I might be forgetting something as it’s been a while since I’ve played around with it)
See how your results compare to mine. I’m also taking into account viewing distance; masks must be visible at the correct Lechner distance (2-3x the width of the display).
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I use the color calibration roms but I find I still have to open games and tweak a lot. I frequently bounce between Street Fighter Alpha 3 and Vagrant Story. One is very bright and the other dark. SFA3 has highly saturated colors close in value that are easy to get lost with shaders. The subtle hues of the clouds and the red’s in the posted image for example. I adjust to much for SFA3 and then Vagrant Story becomes to dark.
One of my shader goals is having a bright, colorful, contrasting image nice scalenline representation. What are you personal shader torture tests? Here are some images of before and after.
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Yep, no way around it if you want optimum results, really. I know I’m sounding like a broken record, but check out Dogway’s grading shader, it’s a must-have for those who are serious about image quality.
As far as the test roms go, you should use the rom for the system you’re trying to optimize. Settings for SNES using the SNES test suite won’t necessarily translate to other systems perfectly.
Torture tests… I usually fire up something with a lot of greens since I can immediately tell if saturation is off by looking at the greens in certain games. For brightness, anything really dark will do. Super Metroid, Silent Hill, Castlevania… just set brightness to the lowest level where all detail is still visible.
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@Nesguy I’m using Dogway’s grading shader in one of my venom shader chains. I find it goes off the rails quick for me. Should I put it at the top of my shader chain or the end? Perhaps I should look more into how others are using it.
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The CRT mentioned in the displaymate article has measured peak brightness of:
Sony PVM-20L5 176 cd/m2 ( http://www.displaymate.com/ShootOut_Part_1.htm )
I’m reading in LCD monitor testing sites that mostly they calibrate peak brightness to 150 cd/m2 for comparison between different models as the 150 cd/m2 is then mentioned to being the normal viewing luminance in normal daylight conditions (they argue at least). Personally I would see if the 150 can be targeted as it leaves some headroom for tweaking to personal preference.
@Nesguy , the brightness values you mention is that from some source or personal preference?
EDIT: @Dogway maybe you could use the reshade version of guest-venom such that you can actually use the scanlines / mask on the calibration software testscreens that comes with your calibrator.
EDIT 2: here are some recommended luminance levels from the calman site:
Recommended Display Luminance Levels:
- Bright Room: 200+ cd/m2
- Dim Room: 140-170 cd/m2
- Dark Room: 100-140 cd/m2
- SDR Reference: 100 cd/m2
- Theater Room projector: 50-100 cd/m2
- High Dynamic Range: 600-2000 cd/m2 (based on commonly available TVs as of July 2019)
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I replaced d65-d50 with grade in my venom chain, seems to work fairly fine. You have to edit the preset manually in notepad or some text editor for this to work properly though.
I also remove the color profile pass.
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100 nits is part of the SD standard, so that should be our minimum. It’s absolutely fine to go brighter than this, but at a certain point you’re going to get clipping. I would consider the 100 nits as a minimum after adding all scanline and mask effects. 150 nits is probably a good maximum. It really depends on the ambient light. I’d say the ideal is the highest level at which you don’t get any clipping OR any eye strain with bright scenes.