Soft Paper Thickness For 1c Official Specimen Stamp?

I have individual 1200 dpi scans of the five O57Xs, I just cropped them in paint and saved the crops in a new file.

The overprint on hard and ribbed paper is 11 1/8 mm long, On the soft paper State the op is 11 3/8 mm long due to the different fonts used.

Photoshop or Photoshop Elements can be used to measure, compare or overlay images with metadata, preferably from the same scanner in the same orientation. Steel rulers have their place, but not for making small measurements or comparing subtle differences in the sizes of images or overprints. A program like VueScan may be required to manage the scanner.

I'll have to play with combining images in Paint.

I use Vuescan and it was with Vuescan that I measured the crop size and over print size in pixels. Divide by 2400 to convert pixels to inches. So the 1200 x 300 pixel scans of the over prints are 0.500 x 0.125 inches.

I have tried photographing the ribbed appearing paper of some stamps with limited success. Part of the problem is I don't have a point light source to shine obliquely on the stamp--plus taking a photo with a camera not square to the stamp, producing a perspective error.

More later. Thanks for the feedback.

Burnside.

I put an O57S and an O57xS together on a card, scanned them at 1200 dpi and opened the result in paint. Cropped a horizontal section of the hard paper and pasted it onto the soft paper image. It shows the hard paper slightly wider than the soft paper.
Also cropped a vertical section and pasted that onto the soft paper image, which shows the soft paper to be taller.