Hello everyone! I am a new RawTherapee developer. I’m currently working on adding new scopes. Because this feature’s usefulness depends on the user experience, I would like to collect your ideas and feedback.
Waveform
This is a standard horizontal waveform. The red, green, blue, and luminance can be toggled individually. The RGB indicator bar on the right shows the values of the pixel under your cursor, just like in the histogram. Clicking and dragging the waveform allows you to change the “brightness” of the plot (also works for the vectorscopes).
Hue-Saturation Vectorscope
Typical vectorscopes plot colors using the U-V coordinates of the YUV color space. This is not very useful for editing photographs, so I implemented two other vectorscopes. The hue-saturation vectorscope uses the HSL color space, which is useful for visualizing clipped colors. In the screenshot, the cross-hair shows the color of the pixel below the cursor. The dashed line, approximately 30° above the red line, is a skin tone line. Keep in mind that HSL is not an absolute color space. The line may not be accurate for non sRGB output profiles.
Hue-Chroma Vectorscope
This vectorscope is in the CIELAB/LCH color space. The a* and b* axes are shown with colored lines while the skin tone line is the dashed line. The hue-chroma vectorscope is better for judging skin tones, but understand that real skin tones vary. Not shown here is the cross-hair for the pixel under your cursor.
Buttons
Currently, there is a new button (the second-to-last one) which toggles the visibility of the second column of buttons. The second column allows you to quickly switch between any scope (from top to bottom: histogram, raw histogram, wavescope, H-S vectorscope, and H-C vectorscope).
There is some discussion about flipping the two columns. Essentially, you would select the scope type first and be presented with available settings in the second column. The scope type buttons would always be visible, while the other buttons can be hidden. I would like to know which set of buttons you think you will use most often. It will help in deciding which layout to use.
Feedback
Again, I would love to hear your feedback and any ideas for improving the new scopes, particularly for the button hierarchy discussed above and any other questions which pop up. The GitHub pull request is here if you want to take a look. I can also answer any questions you may have. Thanks!