We have a ton of blend modes available in Darktable and I was wondering we could collect a “comprehensive” list of examples for each blend mode? For example I have learned nice tricks about Multiply by reading and watching people’s processing tricks.
But can we find cool, meaningful or useful uses for each blend mode? It’d be cool if we had a showcase of at least one showcase per a blend mode.
A lot could be learned from it, by everyone.
I have tried only Multiply and Reverse Multiply. When I have looked into trying to see how they differ (in regards to the image display, not the math), if I use the same settings for both, they look exactly the same, to me. It makes me wonder.
@Tim
They are blended in a different order so you will see the difference with a mask. Multiply will only darken the masked area. Reverse will also impact the area out side the mask because of the order of blending…if there is no mask they will be the same…for example see this recent image shared…then with a 1 EV multiply and then reverse…note in reverse the 1EV bump gets applied outside the mask
Multiply
Reverse
Many of them are no longer compatible if you want to keep to the linear scene referred work flow as they make assumptions about middle grey. They have been grouped and can be filtered by the options icon in the masking section of the module. This shortens the list considerably. Mostly of the blend modes will lighten or darken the image with the associated changes in contrast and saturation as well. Others will only impact the color keeping tone intact. So for example dehaze often leads to a shift of the color and if you want that bump then okay but if instead you blend in lightness you will not impact the color or saturation nearly as much. It is the same for all other modules so you can blend in a hue or color mode so only the hue is blended or in lightness. The math ones are pretty strait forward… Subtract darkens but at very low opacity it can really be a nice rich contrast boost as well as offer a bit of a dehaze like effect. Addition adds the pixels so tends to brighten the image. The trick with most is to drop the opacity to zero and bring it on gradually as often the initial blend at 100% is way too strong . There are lots of references out there…If I recall this is a pretty good one… https://www.youtube.com/watch?v=17Iivi0tmug
Thank you. I learn something new, every day.
the caveat to this was that this logic did not apply to divide and subtract. This may be fixed or not but those reverse modes only acted in the mask. That was some time ago…
EDIT I just checked and it is working the same now for all blend modes when set to reverse…I would have to go back to trace it …not sure when it was corrected…no matter its consistent now…