john@wexfordpress.com (2004-05-09 at 0739.12 -1000):

I found the comments below from a friend of mine on another list provaocative. She is not a Gimp user. I wonder how many of her cautions are universal and how many just dependent on the program used to create the graphics?

[...]

All apps I know can do it, of course people just have to know what is going on. Also, it would be a lot simpler if some web browsers did it right to begin with and transparency worked in them as it should.

GSR

Hi John,

John Culleton wrote:

I wonder how
many of her cautions are universal and how many just dependent on the program used to create the graphics?

Her comments on web graphics are, IMHO, universal, as opposed to limited to one program or another.

Even if a person simply cannot create clean edges (one of the most common mistakes is using "tansparent" on a layer - transparent doesn't work..you need to use the background colour as the background colour on the image around any curved lines. Also that "delete" background rarely gives a clean lift - that all needs to be erased one pixel at a time.) they can go with text only, or visit one of the 1000s of sites that offer free web tools, or avoid curved edges (in most cases jaggies are only an issue around curved edges).

This is a fair comment. Transparency (in GIF, and as supported by IE in indexed PNGs) is limited to one palette entry which is completely transparent, and the rest completely opaque. Usually, smooth rounded edges are obtained by antialiasing the curve, going in grades from opaque to transparent over a number of pixels. Since you can't antialias to transparent in gif, round edges usually look crap. However, if you have a background that isn't transparent, then you can antialias from white to green, say, just fine, and have some of that smoothness kept across an indexing operation.

However, PNG supports indexing much more advanced than that - essentially, an indexed palette entry in png has an alpha component, so with indexed png you can antialias to transparent. However, this isn't supported in IE for Windows. You can also use 32 bit PNG which is funny supported on both IE and Mozilla, but is a much larger file size.

Cheers, Dave.

dneary@free.fr (2004-05-09 at 1806.45 +0200):

However, PNG supports indexing much more advanced than that - essentially, an indexed palette entry in png has an alpha component, so with indexed png you can antialias to transparent. However, this isn't supported in IE for Windows. You can also use 32 bit PNG which is funny supported on both IE and Mozilla, but is a much larger file size.

GIMP does not support indexed RGBA (palette items are four channels, so all can have some level of transparency, vs typical GIF's "one colour is transp only") and dunno which tool does it. But there typical problem is that IE does not support 32 bit PNG as it should, that is, without tricks (some pretty complex). For simplest trick see: http://www.phoenity.com/newtedge/png_degradability/

GSR

I found the comments below from a friend of mine on another list provaocative. She is not a Gimp user. I wonder how many of her cautions are universal and how many just dependent on the program used to create the graphics? -----quote begins-----------
I visit lots of authors' sites and see many that are gorgeous. The thing that always tips me off as to whether they're professionally done or not is the graphics. I cannot stand jagged edges around images, banners, etc. Even the most inexperienced designer can clean that up and do it properly at low resolution, so, I guess it's not so much that it's a sign of being an amateur - to me anyway - that it's a sign of not caring....lack of pride in the work. Even if a person simply cannot create clean edges (one of the most common mistakes is using "tansparent" on a layer - transparent doesn't work..you need to use the background colour as the background colour on the image around any curved lines. Also that "delete" background rarely gives a clean lift - that all needs to be erased one pixel at a time.) they can go with text only, or visit one of the 1000s of sites that offer free web tools, or avoid curved edges (in most cases jaggies are only an issue around curved edges). Round
buttons only look nice if they're done properly. Square (with no transparency and no background) and text buttons work just as well and will give a more "polished" look.

I'm not a web designer by any means, so maybe those on the group who are can offer more insight into this.

-----------end quote BTW I have permission to quote the above from the author.