Problem with Margins

[bdyomtov]

I am having problems centering an image from Photoshop, printing on an Epson P800.

When I choose the "center" option it comes out slightly off.

When I calculate the left and top margin I need based on the paper size and image size (yes, my arithmetic is correct) it comes out further off.

Is there something I'm missing?

[Ian Blogs]

Is this forum discussion any use to you?

"Center" print in CS6 does not center on physical page

[bdyomtov]

Thanks, but I don't think so.

I don't see anything like that in the P800 driver (I'm on a Mac) though I do suspect that there is some concealed item that would fix things.

[bdyomtov]

OK. So I got a clue from the discussion Ian linked. Here's what worked for me:

1. Measure the paper. Carefully. It's not necessarily the exact size specified. I think metric works better than English, but it doesn't matter.

2. Do not check "center" in the driver. Instead, determine the dimensions of your image and calculate the margin needed to center it. Say the nominally 13 x 19 paper is 482mm by 328 mm, and your image, to be printed in landscape mode, is 382 x 254. the left and right margins should be (482 - 382)/2 = 50 mm. Similarly the top and bottom should be (328 - 254)/2 = 37mm.

3. Subtract 3mm, or .12 in., from these numbers and set the left and top margins to these values, 47mm left, 34 mm top.  This will put the image in the center.

Apparently Photoshop adds the 3mm to the left and top margins, without bothering to mention it. At least, I could find no reference to it anywhere. Maybe everyone but me already knew it.

Anyway. I make no guarantees. I'm just describing what worked in this case. Incidentally, I also tried creating a "custom size" in the driver and checking "center." This got pretty close, but was not quite as good.