Jan van Wijk wrote: > On Sat, 02 Feb 2002 20:08:19 -0800, Sid Barras wrote: > > > > ><<I see a 600x410 picture with a size of 26K. > >Didn't you say that you sent 75K? > >Perhaps this accounts for your artifacts.>> > > > >I suppose this is going over my head when we begin to talk about jpeg > >compression, but is my file size is 74k when closed, and stored on the > >server, does it suddenly take up more space on the server when it is open? > > >
I saved Sid's PUG image. It's a 26K jpeg compressed file on my Mac hard drive. Opening it in PhotoShop it yields a 720K image of 410 x 600 dimension. Of course it's already been degraded by the jpeg compression, but I experimented with resaving it as a jpeg. If I save it as a maximum quality jpeg, (PhotoShop's 11 grade), it yields a file of 79K. I think it was around 60 K at a 10 rating. Like some other images I've seen, this image compresses to a very small size because it has a large field of a single color. I've found that I can sometimes compress an image at 10 or 11 quality rating and still end up under 75K. With complicated images, I sometimes have to compress at a 5 rating. If this file was compressed with software that did not offer variable jpeg quality, it could well have ended up as a 26K file with normal jpeg compression. With PhotoShop it comes in at 26k when saved with a 5 quality rating, which is "Medium Quality." Paul - This message is from the Pentax-Discuss Mail List. To unsubscribe, go to http://www.pdml.net and follow the directions. Don't forget to visit the Pentax Users' Gallery at http://pug.komkon.org .
