Epson V750 Scans Out of Square

[agprint]

Greetings,

 

I was wondering if anyone else was having the same problem as I am having with an Epson V750-M?

 

When scanning a 4x5" negative (both on the glass and in the Epson film holder) I noticed that the image

was SLIGHTLY out of square.

 

I then checked the film itself -- same result.

 

After that I took an old scientific glass plate used years ago for making circuit boards. It has numerous

precise grids. When scnned, the resulting image is just slightly out of square. I have tried it on 2 different

V750's with virtually identical results.

 

If I scan this glass plate with my Epson 1000XL I get an almost perfectly square image.

 

I can't find any other references to this "problem" or irregularity.

 

Is this something to be concerned about?

 

Thanks,

 

Bill

[jamespjones]

That is interesting. Is it possible for you to post the scans? I just did a quick check and I

didn't notice an irregularity. I wonder what may be causing it.

<br><br>

James<br>

<a href="http://www.photographyri.com">photographyri.com</a>

[mendel_leisk]

I had a similar experience with Minolta Scan Elite 5400. With the slide holder at least, I was able to put shims on the side walls of the platen, to rotate the slide to compensate.

[leonard_evens]

Do you mean that the scanned image is rotated slghtly? Or do you mean that instead of getting a perfect rectangle you get a trapezoid, i.e., that parallel grid lines in the film converge slightly in the scan?

 

The former would be a minor annoyance because you could shim the border of the glass frame to compensate. The latter would be much more serious. Also, if that is the case, is it caused by the hardware/firmware in the scanner, or is caused by the software which interpets the raw scan?

[peter_gilbert3]

Bill:

 

Could this be optical distortion? I know simple office copiers can "never" make a copy in perfect registration with the original.

 

Peter

[agprint]

I will try to post sample scans. Unfortunately, I am travelling and don't have the digital

files on this laptop.

 

To try and describe the situation more clearly... it is not simply that the rectilinear shape is

rotated. That I know how to correct easily.

 

Rather, imagine the a square. Now imagine the top and bottom horizontal edges perfectly

aligned with guides in Photoshop. If that is the case, the vertical edges do not align with

the Photoshop guides - the vertical edges are parallel to one another, but they "drift"

slightly to the left from top to bottom.

 

I would estimate the drift at about 1 degree or so, but it is noticeable on screen at high

magnification. The two V750's that I have used (my own and a friends) have exactly the

same result. Interestingly my 10000XL produces an image of the same target that is dead

on.

 

I know this can be corrected in Photoshop, but I would imagine that correcting this lack of

rectilinearity would slightly diminish the resolution in that portion of the image.

 

Thanks again for the help,

 

Bill