Hi Bill
you can attach photos to a post
I assume the process is the same for a Mac as for a PC
attachments........
you need to be in full reply mode, not quick reply...
if you scroll down your page you'll see an 'attach files' box...then a 'manage attachments' button...
hit the button -
a new window should open - hit the browse button to find the file on your Mac - hit the upload button to upload the image to SR...
assuming your pic is within the prescribed limits of size (you'll see them there when you upload) all should be well
D