png transparency

[loseyourmind]

I'm trying to create transparent images using the png format (since there are licensing and royalty issues with using gif)
I've tried to export my images using the 'save for web' thingy, and the transparent portion of my image ends up grey
when i display it in a web page. I'm using these graphics for both web pages and in applications. Anyone happen to know how to actually make a png transparent.

also, anything you might know about retaining the alpha chanel info might be useful, although i haven't ried to save any alpha chanel info in png's yet, but most likely will soon...

Thanks

Otter

 

[sophisticate]

Don't worry about licensing issues with the gif format unless you are developing software that will allow people to read/save using the lzw compression algorithm. You can make as many gif images as you'd like in Photoshop without hassle because the component of PS that uses that algorithm has already been licensed through Adobe.

Have fun,

brendanc@icehouse.net

 

[loseyourmind]

Okay, the gif's and stuff, i guess i could still use them, but I'm also looking to do some stuff where i can't have the gif ghosting around my images when the bg is transparent. so i kinda have to use the png format to retain the alpha info. any time i've tried it, the transparent parts just come out grey....

don't get it at all.

 

[InTenSe]

PNG support in IE browsers are very strange, in IE4 PNG with transparency was supported however in IE5+ PNG with transparencies or an alpha show up as a grey box as you had described. You PNG files are more than likely correctly exported (since you described the grey box issue). However I think this is just a browser limitation. Navigator may very well have better support for this but as I don't use it I can't be certain of it.

I hope this helps clarification.

 

[boyfromoz]

I think maybe you are asking the wrong question.

Try asking "How do I lose the ghosting effect around Gif's when exporting?" as opposed to how to use epxort a PNG wihtout greyness. I've mucked about with PNG's and on the whole they are not as good as Gif's. For starters, on average across different picture makeups, they result in larger file sizes.

It can be done without much trouble using matting colours mathcing, masks etc. GollyG is the one to explain it best in my experience.