If you need transparency over an unknown or varied background color, or you have shading or gradients, you need 24-bit PNG
If you have a known color background and flat colors for art, 8-bit PNG or GIF will work fine. You can set the "Matte" color to match the background.
You by default are working at 72dpi on the web (mac standard). So save the file at the size you want it when the resolution is 72dpi, or alternately 96dpi (PC standard).
----- Original Message -----
> HI All:
> I'm saving an image file for a web page. It may be used full size (7x7") and as a small logo.
> The artist created it for printing on a sign, and now I'm configuring the image for further usage to the client.
> For the web, I'm making RGB, reducing the file from 7x7" @ 300ppi, to 3x3". I shall reduce it to 150ppi, or maybe even 72ppi. I want it to look good but not slow down the screen loading.
> It has a transparent background so can't save as a JPEG for web. Using Photoshp CS5, "Saving for Web and Devices." as a PNG file. Do I choose PNG-8 or PNG-24?
> I don't normally prepare for web, so I appreciate your thoughts.
> Very best!
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