Hi Hollow4!
I am definitely still a bit miffed about the centering on this machine! I do not have these issues on the 4000 or 7800, so having them on a newly updated machine is very frustrating!
I haven't tried sheets yet, so you have my sympathies there!
However, here is something new that is definitely wrong: I setup a custom paper size 16x11 with 0" margins. Image is sized 16.5 x 11" ... I print using Roll Paper - Borderless (Auto Expand) using the Double-Cut method (which I've done hundreds of time on my 4000 flawlessly) and get this >>>>> it MISS CUTS the paper by 1/8" ... meaning it cuts off 1/8" of the image on the first cut, and then again cuts leaving an 1/8" of white paper on the second cut ... but the size is exactly 11". (by the way, I understand why my 4000 had to waste 3" of paper using this method - paper suction, but the roll cutter on the 9890 is in a different location, and should waste MUCH less paper.)
Mind you, this is on Mac OSX 10.6.7 and through Photoshop CS5. I'm going to dig out my trusty 10.5 install (with CS3) and see how that behaves.
Second scenario: Crop image to 16 x 11 and then size to 15 x 10. Object: to get a 1/2" border around image. Same paper setup 16x11 roll paper. Print this time with "Roll Paper" and Normal Cut (only one available). This time my left-right centering is perfect. But Normal Cut leave me with extra paper to trim. Now I could have sworn my 4000 would let me double cut that paper to 11", but I was probably using "Roll Paper - Borderless (Retain Size) <-- that has been my preferred method since it allows me best control over image placement and how I want it trimmed.
With the 9890 it just will not allow me to center a print and print borderless with "Roll Paper Borderless (Retain Size). It always pushes the image an 1/8" to the left, even when the image is more than suitable size to cover the paper.
My 3800 also centers without any problems.
I'm going to give my 10.5/CS3 install a go and see how that prints.
Per your sheet issues. I would not let epson off the hook. If you print a 16x20 on a 17x22 sheet is should be perfectly centered no questions asked. I don't want to risk my Baryta papers yet, but I'll try with a sheet of Hanemuhle 308 photo rag (will get matted, so doesn't have to be perfectly centered) and let you know how that centered.
Did you update the firmware on your printer? I did. Now I'm wondering if I shouldn't have!
Yes, HUGE printer. I had much 'fun' carrying up two flights of stairs with 3 of my buddies. Glad I don't live on the 3rd floor. Don't think we would have had the gas to go another floor!
All gripes aside, I'm loving the output of the printer. Very glad the printer doesn't auto switch blacks (unless you tell it too).
-cj