A question about the output sharpening in LR, if I export say 600x600 and apply the sharpen for screen for that size, does LR add that output sharpen to any sharpening I have already applied in develop modual, or does it mitigate the dev sharpen in favor of the output size?
I ask because I'm finding images resized in LR noticably softer to images exported and then resized in PS using fit image. Thanks Wayne
Output sharpening in LR is always added to any sharpening you've applied in the Develop module.
The Develop module's Detail pane's controls are for capture sharpening. This is applied at the image's original (a.k.a. "native") image resolution, without image resizing or resampling. This is output-independent sharpening.
In contrast, output sharpening is applied by LR to the final resized image (in your example, 600x600). It is very much output-dependent.
The two sharpening modes are designed to work together, but the controls for one do not affect the results for the other. So, specifically, your choice of output image size (600x600) and choice of Output Sharpening (e.g., Standard, Screen) has no effect on the capture sharpening settings or results in the Develop module's Detail tab.