I've followed Engauged's tutorial for adding alpha channels to bitmaps using Imagetool and Photoshop, but whenever I run a psd conversion in Imagetool, it comes back with a nice little bitmap complaining about unconverted layers in the psd. The psd file has two layers in it; the basic bitmap layer is the lowest layer and the required alpha channel is the one above. Colour depth is 24-bit and I'm using PhotoshopCS; has anyone any idea where I'm making a mess of this?Thank you.-Dai

Yeap.A "channel" is NOT "above" a layer, but rather a channel, which is a layer on the channels palette, not a layer on the layers palette.While you might create it initially as a layer, often modifying an existing layer, you then need to save or copy it to a channel layer, and then get rid of the layer version.Read the help about creating an alpha channel for details.

Dai, since you are using Photoshop CS, click on the Channels tab, create an empty Alpha Channel, then cut-and-paste your layer from the Layer tab to the Alpha Channel. Delete the unneeded layer, save the .psd and then use ImageTool.exe as described.

Thanks guys - both of your replies were much appreciated and very enlightening!-Dai