Reply To: Image degradation on resaving from PSD to JPEG

I'm with Deke McClelland on the subject of downsampling: bicubic sharper is best avoided because it almost always oversharpens, especially when you're making big resolution changes. Regular bicubic gives a far better result >95% of the time, and you can then tweak the sharpening with Unsharp Mask or Smart Sharpen as needed.

The answer to your question is, “It depends.” Sharpening is one of those esoteric subjects that is highly dependent on the final output device, not simply the final resolution. What works beautifully for a good quality photo printer won't be optimum for 150-line screen on an offset press, nor for viewing on a monitor. Deke has several excellent books, several Lynda.com titles and various tutorials on deke.com that go into this in depth.

If you're designing for high-end magazine or book publishing, you are always going to be better off treating each image individually and carefully in Photoshop. I would recommend a plug-in such as the excellent Nik sharpener, which fine tunes for specific types of final output. The rest of the time you can let InDesign's PDF export do its stuff (it's the exact same engine as Photoshop, because the actual Photoshop code was baked into InDesign long since) and get great results with far less time spent agonizing over details.