I’ve been reading the couple of threads re image quality and degradation. While working on some recent images I have had to be careful which programme handles the compression. Encouraged early on to let Freeway do the resampling I have been happy to generally do just that. However it isn’t always the way to go and I have uploaded a test page here http://tinyurl.com/be5nnx . Hope it is useful.
This may have some bearing on the chat about images degrading over time. Not only are monitors better as suggested but the resampling algorithms used are no doubt better these days too.
No. The image is a photograph, not a scan, of a granite plaque with the halftone image engraved on it. At full size there is no evidence of moiré. It only happens when imported into Freeway. Photoshop did the reduction from full size SLR Jpeg to the 183px high version you see in the linked page.
Or rather, when imported and then scaled down in
Freeway, as opposed to being scaled down first
and then imported?
Sounds like this is an effect of different kinds
of interpolation, the process of recalculating
the pixel structure size of an image. Freeway’s
interpolation method is different from
Photoshop’s default interpolation. It gives
slightly crisper results, but this can cause
problems such as the ones you’ve seen. There’s no
single ideal interpolation process for all
images, so in this case it looks like resizing
images externaly is the best route for moiré-free
results.
Thanks Keith, your qualification there is absolutely correct, and your other comments too.
My reason for posting at all was that it is worth keeping abreast of the new algorithms and comparing results to assess which works best in particular circumstances. One size fits all solutions can be used in many cases but there are always those exceptional examples that need extra consideration for best results overall. Certainly don’t want to give the impression that I’m knocking Freeway though. On the contrary, the more I examined the images the more I was impressed with the job it does (halftone areas excepted in this case of course).