Pardon the cross post, but I'm frankly amazed I received no help at the Adobe forum
When printing landscape images from Lr3 I am ending up with unequal left/right margins because I believe Lr has an inaccurate determination of my HP B9180's page bleed dimension (trailing edge of paper). It's only 1-2mm but definitely noticeable if the edge of the print is close to the frame. I tried to account for it with 1mm modifications to the Lr top/bottom margins (image's left/right), but ended up with the same printed margins(?) A couple of questions ...
First, which may require someone's knowledge of the printer itself. The printer's special media tray has a dashed line for paper alignment, but it is ~2mm wide. Therefore, depending on if I used the front or back edge of the alignment it may account for the problem ... except that I'd hope the printer actually has an optical sensor for detecting the paper's edge(?)
Second, from what I've read (eg, Martin Evening's excellent text), the printer's page bleed dimensions should be built into Lr margins ... correct? There inlies the mystery why my margin modification didn't remedy the problem.
Lastly, I suspect I could find the answer empirically, but I don't want to waste the paper and ink. However, if I do need to to I'll report back (... hopefully without more questions ...<g>...)
TIA & Cheerios from the Avalon Peninsula