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billy4030
02-06-2019, 1:40pm
Learning Photoshop and just playing with Lab colour mode. Is this adjustment normally done at the beginning of all your ps adjustments or at the end after all the ps adjustments.
Tia

ameerat42
02-06-2019, 3:35pm
Given "ps adjustments" stands for "Photoshop..."

A good question, othwerise. Although I have not used it, I'd say that you'd be doing it fairly early in the piece.
OK, so what else would you do - cropping, rotations, re-sampling? These wouldn't matter, but the main tonal
and color adjustments would be done using the LAB profile.

arthurking83
03-06-2019, 10:44am
The Lab colour mode has a wider gamut, that's for sure, and ideally it'd be best to work with more detail.

BUT!! .. (and there's always a but) .. does your monitor support truly wider gamut colour space?

i.e. you really need a high quality monitor AND more capable graphics card(if you don't have them.

Dunno your system specs, but there are ways to see if your hardware can support higher quality settings.

So unless you are 101% sure that your computer hardware is capable of rendering the wider gamut of colours, I'd say stick to RGB.
Reason is, if you're tweaking and twiddling colours, and behind the scenes you do get better colour fidelity(that is in the actual file) .. the lowest common denominator(either your monitor of GPU) may be showing you(rendering) something completely different.

It's the WYSIWYG effect.
With all suped up, high quality hardware, you will most likely see the benefits.
But lets say your monitor is only a 6bit(colour) model, it can't display the colours in the file .. so you don't see what you're getting.

billy4030
03-06-2019, 12:41pm
The Lab colour mode has a wider gamut, that's for sure, and ideally it'd be best to work with more detail.

BUT!! .. (and there's always a but) .. does your monitor support truly wider gamut colour space?

i.e. you really need a high quality monitor AND more capable graphics card(if you don't have them.

Dunno your system specs, but there are ways to see if your hardware can support higher quality settings.

So unless you are 101% sure that your computer hardware is capable of rendering the wider gamut of colours, I'd say stick to RGB.
Reason is, if you're tweaking and twiddling colours, and behind the scenes you do get better colour fidelity(that is in the actual file) .. the lowest common denominator(either your monitor of GPU) may be showing you(rendering) something completely different.

It's the WYSIWYG effect.
With all suped up, high quality hardware, you will most likely see the benefits.
But lets say your monitor is only a 6bit(colour) model, it can't display the colours in the file .. so you don't see what you're getting.

Arthurking83, thanks for your reply. My monitor is an Dell Ultrasharp U2713h. Its specs say 99% Adobe Rgb. https://www.dell.com/hr/business/p/dell-u2713h/pd
My graphics card is a Nvidia Quadro K2000D.. https://la.nvidia.com/content/PDF/data-sheet/DS_NV_Quadro_K2000D_OCT13_NV_US_LR.pdf So I think the equipment is ok. Although this pc is getting a few years old.
But my initial question was is this adjustment done at the beginning of the process before any other adjustments in Photoshop, or at the end or doesnt it matter if its at the beginning or end

arthurking83
03-06-2019, 1:07pm
..... So I think the equipment is ok. Although this pc is getting a few years old.
.....

:th3:

As the saying goes, there is no silly question .. BUT! there is a point of view along the lines of ... is it the right question.

One more step to confirm you're actually seeing aRGB colours is to be sure that the graphics card's settings is in 10bit mode.
If not, you're not seeing the full gamut of aRGB.

If you have the nVidia control panel service running it's an easy step to check/make.

This assumes you're connected the screen to the PC via DP, and not DVI too.
DVI doesn't allow, or have the capacity too run 10bit colour mode. DP does.
The assumption comes from the point that you've invested in high end gear, and prefer to use it in this manner. So you're more likely to have used the DP port, and not the DVI port as the connection.

IF .. you don't see the option as in my screencap in the control panel below, it's most likely because you've used the DVI cable. ie. it's in 8 bit mode.

139911

From memory, no OS sets colour depth in the graphics card driver to 10bit by default(lowest common denominator settings at play again)

Then once you're sure your system is set to 10bit colour depth .. then for sure, set PS to run in Lab mode all the time .. start to finish.
Also assuming you're editing psd's and or tifs .. and not jpgs.

Hope that helps.

billy4030
03-06-2019, 2:17pm
Thanks Arthur for that info. I was using DP as the connection to the monitor. But I ran the Nvidia control panel, and it was set to 8bpc. Now changed to 10 and dynamic range changed to full. My settings are now as your picture, except im using 1920x1080 as I find the other resolutions a bit small for my eyesight. Thanks for that info