Pages: [1]   Go Down

Author Topic: Calibrate & Profile-Where to start with Brightnees, Contrast, RGB Gains?  (Read 475 times)

Charles Beasley

  • Newbie
  • *
  • Offline Offline
  • Posts: 36
    • http://www.charlesphotography.com

(I realise this may have been discussed many times here but I spent 2-3 hours searching but haven't found an explicit answer, so forgive me in advance if it has.)

 I have a Dell 32" Ultrasharp U3219Q and have a new Calibrite ColorChecker Display Pro on the way.
I tried to see if I could download the instructions in advance but all I found so far is this:
https://calibrite.com/us/learning-centre/ideal-settings-for-screen-calibration-for-photography-with-colorchecker-display-pro-and-plus/
which doesn't address my question exactly other than saying "reset your monitor back to factory defaults," but I am wanting a more basic answer to the question where to start with the brightness, contrast and the RGB gain controls?

FWIW, I calibrated/profiled yesterday with my old i1 puck and Display Cal to color temp 6500K, white level 140, black level 0.5.
During the calibrate part, the monitor settings are  Brightness 33%, Contrast 75%, RGB gains: R97%, G94%, B92%.

To start from scratch, should the gains be this high, or should the brightness be higher and the gains lower to reach the desired white level? (I have read that some monitors/displays
may not natively be able to reach low white levels say between 80 and 120, so I want to avoid that.)

Also, I am wanting to have a fairly low contrast ratio between white and black points, where should the Contrast setting start out?

TIA,
CB

So since the gains are already pretty much maxed out,
« Last Edit: October 28, 2021, 02:53:00 pm by Charles Beasley »
Logged

PhilipCummins

  • Full Member
  • ***
  • Offline Offline
  • Posts: 119
Re: Calibrate & Profile-Where to start with Brightnees, Contrast, RGB Gains?
« Reply #1 on: November 01, 2021, 06:34:05 am »

Not an expert but I have a similar Dell, Custom Colour generally is at 100 initially which means RGB should be roughly tuned to generate your D65 White Point requested. However, the i1 Display Pro with i1Profiler should be able to determine as one of the optional steps whether RGB requires adjustment to reach D65, so you would generally adjust whichever colour level is too high down from 100. If there is a colour that requires adjusting up (and is at 100 already) you would adjust the other 2 colours down to give it a bit of headroom to adjust with, so you could end up around 95 (checking my monitor right now I got 95, 95, 97 for RGB from it being previously adjusted but probably could also work with 97, 97, 99 for example - but you'd test 100 to see if it's too high to check). For brightness you would adjust the monitor brightness controls to set what Luminance level you wanted (say, around 120 cd/m2 but could be higher/lower depending on what lighting you have and how bright you prefer it) and not adjust RGB. You probably would want to adjust brightness first, then return to RGB levels in case the monitor isn't adjusting RGB properly if raising/lowering brightness.

Unfortunately the i1Profiler software doesn't give me any feedback on adjusting live Contrast ratios (which would be useful if it flipped between Black & White so I could set it) so you'd probably want to experiment with the monitor's Contrast settings using DispCal GUI (or Argyll) to measure what Contrast setting works best on your monitor while maintaining requested Luminance levels for the ratio you wanted to use. Contrast generally appears to start off around the 75 mark usually (or there could be a point where adjusting it up doesn't make any difference to brightness which could be a good starting point as well).
« Last Edit: November 01, 2021, 11:51:10 pm by PhilipCummins »
Logged

digitaldog

  • Sr. Member
  • ****
  • Online Online
  • Posts: 19754
  • Andrew Rodney
    • http://www.digitaldog.net/
Re: Calibrate & Profile-Where to start with Brightnees, Contrast, RGB Gains?
« Reply #2 on: November 01, 2021, 10:54:56 am »

Why are my prints too dark?
Why doesn’t my display match my prints?
A video update to a written piece on subject from 2013
In this 24 minute video, I'll cover:

Are your prints really too dark?
Display calibration and WYSIWYG
Proper print viewing conditions
Trouble shooting to get a match
Avoiding kludges that don't solve the problem

High resolution: http://digitaldog.net/files/Why_are_my_prints_too_dark.mp4
Low resolution: https://youtu.be/iS6sjZmxjY4
Logged
Author “Color Management for Photographers" & "Photoshop CC Color Management" on pluralsight.com
Pages: [1]   Go Up