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View Full Version : HELP! Sharpening/Jpegging nightmare


jdal
30th October 2009, 05:05 PM
PPing this pic's driving me nuts (this version is resized only)
http://www.dalrymple.me.uk/personal/Sharpening/FullSmall50PC.jpg
I've decided to make my pics a max of 900 to stop the Gallery software resizing, so I never expected filesize issues. I try and keep files at < 230k, but this thing came out at 400 when I jpegged a sharpened version it via Photoshop SaveForWeb with enough quality to suppress the JPEG artifacts. I assume this was because the sand is as bad as it gets for the JPEG algorithms to compress, and sharpening exacerbates the situation.

For reference this is a 100% crop of a part of the image:
http://www.dalrymple.me.uk/personal/Sharpening/100PercCrop.jpg

This is it with quality at 50%, results in a 250k file when fully sharpened.

http://www.dalrymple.me.uk/personal/Sharpening/resizedSharpened50PC.jpg

and this at 80%:
http://www.dalrymple.me.uk/personal/Sharpening/resizedSharpened80PC.jpg

You can see how the Jpegging has affected the fishing line.

The only way I seem to be able to get the line clear at about 230k filesize is to select the fishing line and only sharpen that. This is easier said than done with single strands floating about. The image probably looks better without the sand sharpened as it's distracting, so the best I've come up with is just the main body of the line sharpened. Including the single strands of fishing line and sharpening doesn't really work, the edges of the line look strange.

Can anyone share any techniques they use in these kinds of situations? This is an extreme case of a problem I seem to have in getting clean web images.

I'm using the WPPro plugin to resize and the FocusMagic plugin to sharpen

RAW original here (http://e-group.uk.net/forum/PPing this pic's driving me nuts (this version is resized only))

snaarman
30th October 2009, 06:02 PM
I think you have got yourself a tricky one there.

I usually resize to 800x600 then apply one of my subtle custom sharpening filter masks to recover the bite in the small picture. Generally I can get a 200Kb file that doesn't have jpeg errors and doesn't look over sharpened this way.

This example here - with all that sand - would be a testing example. Its almost inevitable that the file size will balloon with all that sandy detail. I am not so certain that having the sand soft would benefit the picture, so it may be you have to accept a large file in these circumstances..

Having recently (and expensively) upgraded to CS3, I am immediately tempted by the Smart Sharpen option. You can set that to avoid sharpening the shadows (and thereby creating unwanted noise) while still sharpening the rest of the image. However that trick won't work on this picture.

So there we are: Some pictures are just born to be huge :-)

Pete