Graphics: Saving options for JPG in Photoshop

started by Terryk on Jan 6, 2004 — RSS Feed

Terryk Terryk
Posts: 9

I'm graphics-challenged and could use some help...

When saving a JPG in Photoshop (I'm using an old version: 4), it gives these options:

- Baseline 'Standard'
- Baseline 'Optimized'
- Progressive / # of Scans

Can anyone explain the difference to me, and which one offers the best optimization for the lowest file size? I've got GIF optimization figured out, but still end up with weighty files when saving as JPG.

TIA,

Terry

Joe Gillespie Joe Gillespie
Posts: 528

Saving JPEGs has come on a long way since Photoshop 4. There is now a 'Save for Web' feature which gives a side-by-side comparison (before and after) and you can easily see where the critical compression point is in real time. You can also see if JPEG is the correct format because you can compare GIF and PNG versions in the same field of view.

The options you mention are still present when you do a regular 'Save as...' with JPEG.

'Baseline Optimized' gives a slightly smaller file size than 'Baseline' at the expense of compatibility with older browsers. I wouldn't worry too much about older browsers these days, always use 'Optimized'. It is ticked as default in more recent versions of PS.

'Progressive' isn't very relevant these days either. It builds the picture up in the browser as the data downloads. It's only really significant with slow connections or very large images. Seeing the image gradually build up in resolution gives the impression of a faster download to the viewer but if you measure it with a stopwatch, actually takes longer. This is unchecked by default now.

The 'Save for Web' feature that was introduced in later versions, also includes a 'blur' control that reduces filesize further, although I've never found it particularly useful.

The only thing that really matters with a JPEG is the 'Quality' slider and the little extra effort involved in catching that 'sweet point' where compression artefacts just become unnoticable.

Terryk Terryk
Posts: 9

Thanks for the detailed reply, Joe. Much appreciated!

Terry

Ron Ayalon Ron Ayalon
Posts: 1

This detailed reply is very good - I agree with each point for the most part.

Priam Vathaa Priam Vathaa
Posts: 19

Nice information is given. Thanks Joe

Virtual assistant and Data processing

You must login to reply