bbd10 Posted July 24, 2016 Share Posted July 24, 2016 Color correction requires very subtle adjustments. But adjustment layers work like a sledgehammer. In color balance adjustment one percent is the smallest amount you can apply. You need also blacks or mid shadows. Not only shadows, mid-tones, and highlights. In curves adjustment, you need many points to obtain the desired result. Adding points are easy, but the placement of them is so coarse that it is almost impossible to build the desired shape of the curves. In such cases blend ranges option is the rescue. A small cog near blend mode selection list opens blend ranges dialog window. Layer blend ranges dialog has two graphs. The source layer ranges graph can be applied to increase the precision of adjustments. You can simply drag nodes on the source layer graph down to, for example, 10%, and then 1% change in adjustment layer will become effectively 0.1%. This is particularly efficient for curves adjustment. Large node movements result in small effect and you can understand what are you doing. The underlying composition ranges graph allows you to fine tune tonal ranges affected by adjustment layer. Left side means darks, right highlights. You can use different shapes here, but for example, the gaussian-like shape will bring the focus of the adjustment layer to this tonal range where curve maximum is set. You have to be really careful, though. Linear curves or strange shapes can lead to banding and other unwanted effects. Probably you are looking for something more subtle than example included in the Affinity Photo help. Another option found in blend ranges dialog is Blend Gamma. By default, this option is set to 2.2 which is normal for regular sRGB blending. But in a case of a very subtle adjustment, using linear RGB color space can be helpful. In this case, you have to change a value of blend gamma to 1. Mysterious coverage map should be left as is, without any modifications. With this choice, you can change antialiasing which can be important for hard-edged objects like lines or text. Blend ranges can be used with live filters also, but this is not so straightforward like with adjustment layers. There is no cog shaped blend ranges button in live filters. You have to open this dialog window from any other layer and leave it exposed. Then when you switch to live filter, then changes in blend ranges will be applied to the filter. You have to be careful with that, though. Blending options can be applied not only to master but also to red, green and blue channel individually. This is a very nice possibility, but usually not easy in implementation. The combination of complex adjustment layer with a complicated transfer function in red, green and blue can be very difficult to understand. In effect, you can commence using trial and error method which is not a good approach in this case. To use blending options with adjustment effectively you not only should have to just visualize the desired effect, but all actions have to be planned ahead. For instance, you know what is characteristic of Fuji Provia 400X film so you can plan your actions for contrast, color balance, hue and saturation enhancements in very narrow tonal bands. You can apply 3D LUT adjustment in this case, but even then, some subtle corrections are necessary. Attachments: Source Range Reduced - Blend Options with Source Range set to 10% Colour Balance Extreme - Color balance adjustment where Yellow/Blue with 43% means 4.3% when blend options are applied Midrange of Midrange - Blend options composition ranges graph narrowing corrections to midranges and effectively narrowing midranges too. Corrections are applied in linear space. Precision Curves - Curves adjustment which without blend options looks like a straight line. Sorrento - New image colorized with described technique to be coordinated in color with images scanned from old positive film. MacGueurle 1 Quote Link to comment Share on other sites More sharing options...
anon1 Posted July 24, 2016 Share Posted July 24, 2016 Blend ranges can be used with live filters also, but this is not so straightforward like with adjustment layers. There is no cog shaped blend ranges button in live filters. You have to open this dialog window from any other layer and leave it exposed. Then when you switch to live filter, then changes in blend ranges will be applied to the filter. You have to be careful with that, though. just klick on the cog icon in the layers panel (next to the blend modes dropdown) "Color correction requires very subtle adjustments. But adjustment layers work like a sledgehammer." - you can also just lower the opacity of any adjustment layer to get down to 1/100 of an effect so that it only has 1 /100 of an effect Blending options can be applied not only to master but also to red, green and blue channel individually - I´d even appreciate the option to be able to use LAB/ CMYK values for the blend if curves in a RGB like it is possible in levels and curves adjustments Quote Link to comment Share on other sites More sharing options...
bbd10 Posted July 24, 2016 Author Share Posted July 24, 2016 just klick on the cog icon in the layers panel (next to the blend modes dropdown) "Color correction requires very subtle adjustments. But adjustment layers work like a sledgehammer." - you can also just lower the opacity of any adjustment layer to get down to 1/100 of an effect so that it only has 1 /100 of an effect Blending options can be applied not only to master but also to red, green and blue channel individually - I´d even appreciate the option to be able to use LAB/ CMYK values for the blend if curves in a RGB like it is possible in levels and curves adjustments Lowering opacity should be considered a first choice in most cases but with source range curves you can obtain nonlinear behaviour of adjustments. Blending with other color models works with other components as expected but blending through different color model can be a little tricky to design as a general solution. I'd rather appreciate an option to work with color wheels for lift-gamma-gain, shadow-midtone-highlit wheels or even color bars. With ranges definition and linear space naturally;) Attachments: Blend Options in Lab - Nonlinear blending and Lab Lift-Gamma-Gain and SMH-Log-Lin - Color wheels for primary color correction Bars - Primaries color bars as an alternative for lift-gamma-gain wheels. Quote Link to comment Share on other sites More sharing options...
anon1 Posted July 24, 2016 Share Posted July 24, 2016 Blending with other color models works with other components as expected but blending through different color model can be a little tricky to design as a general solution. - should not be much more difficult for blend ranges than it is for curves well you can fake all of those three by using curves Quote Link to comment Share on other sites More sharing options...
bbd10 Posted July 24, 2016 Author Share Posted July 24, 2016 Tricky does not mean impossible. As I know, internal architecture of Affinity Photo allows even more complicated transformations but this has a price. Transformations of color models can be performed with high accuracy but with each transformation, you always introduce some rounding errors. In the case of blending, transformations can start to proliferate like rabbits. You can also find valuable using different color models for different layers;) Yes, I know everything can be done by using curves. Everybody use curves. So why colorists in film industry does not? This is problem of usability. You do not have to think in "curves category" when you color correct image. In Affinity Photo we can use scope panel with RGB parade or with vectorscope. Then it is faster to correct color with Lift-Gamma-Gain wheels than with curves. The same you have with shadow-midtone-highlit wheels. To correct something in midtones with curves you have to enter two or three points for each color curve and adjust every curve individually. With color wheels small move of central point in midttone wheel is everything you have to do. Quote Link to comment Share on other sites More sharing options...
anon1 Posted July 24, 2016 Share Posted July 24, 2016 input of your camera is not floating point precise anyway, it´s not even accurate enough to define a precise value in 8bit recording, any noise pattern or other distortions will be much more dramatic than the rounding issues will realistically get yeah more options are always welcome but I´d say the basic functionality should be added first and then redundant ways can be added Quote Link to comment Share on other sites More sharing options...
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