07-24-2021, 04:46 AM
(07-24-2021, 03:14 AM)PixLab Wrote: ok, so the stretch contrast under the auto button automatically adjusts contrast? Am i understanding you correctly?
No, Colors > Auto > White balance... will do it (on B&W as well)
i eventually want to learn how to do it manually,
If you are selling you laser thing,
Yes! indeed IMHO you will need to learn to do it manually for example if a customer want to engrave something which appear in the colored photo, but disappear with all the "Auto" function in B&W, you will need to know how to make it appears when it becomes B&W.
I would recommend you to learn the "Levels" first (it's a simplest version of the Curves), the "Auto input levels" in that tools is exactly the same as the "Auto > White Balance..." I spoke above
2 quick links I found for a good start to learn "Levels":
https://patdavid.net/2011/07/getting-aro...ng-levels/
https://www.youtube.com/watch?v=U6kFhN4T8uc
but its hard for my eyes to see the difference with greyscale so i cant always produce the best images for laser engraving.
You are no obliged to start with a B&W, personally I would do Levels in Colors then use the mono mixer (Colors > Desaturate > Mono Mixer...) or use any desaturate method that give a quick result I'd like AFTER adjusting the color,
Why? because your conversion in black and white will always depend about colors and darkness/lightness of these colors.
I love this tool -> Colors > Desaturate > Mono Mixer
https://www.youtube.com/watch?v=_SdjdPGb4B0
But it's me only, if you don't like it, in the Colors > Desaturate menu you have other tools to chose from
Also when you have finished to adjust your B&W picture, you might want to take a look at this tool > Menu Colors > Threshold... If laser engraving is just made of black and white spots (no gray gradients), you might love this tool. But I do not have any idea what type of B&W you need to do laser engraving
PERFECT!!! THANK YOU THANK YOU THANK YOU!!
my laser does "greys" by varying the output power so it can do some shading. All images need to be B&W. the software that i apid for that the laser actually uses is called lightburn, and can do some pretty good image adjustments in it. However, having gimp or adobe is a plus.
i can see colors really well, but my brain has a hard time seperating greys from eachother. greyscale has always been an issue with me, its almost a type of color blindness haha. Ill have to see if there is a way to do split view with B&W photos so i can see the greyscale image and color image next to eachother whilst i adjust levels or curves?
I will look at those links and continue to use these forums and next time ill edit or reword my starting posts not to sound so spammy haha