SilverFast X-Ray does not obey dimensions

[Nick]

As shown in this image I'm trying to use the US Letter format. But,l the expert settings are automatically changing based upon the frame. I am trying to scan OUTSIDE the prescan area. The prescan keeps cutting off every single image we try to scan. No matter the size, no matter how big or small, the prescan will cut off a border. So I tried to use a US Letter or A4 size so I can just crop it myself. But, nope. Auto settings!

How do I stop this ridicilousness?

[LSI_Ketelhohn]

Dear user,

when you set a certain Preset (printing resolution) and Format (Print size) the necessary resolution will be calculated based on this.
So if you set it to print in letter size and a Preset of 300 ppi the scan resolution will adjust to a value that creates an image of that size.

You can not scan outside the prescan area. The prescan area resembles the area your device can visualize in the current scan mode. In most cases this is the the width of the sensor or lamp.
Some scanners like the EPSON V800 have two transparency modes. Here the area depends on the transparency mode selected. This device for example can only use the infrared correction in a limited area and offers a smaller scan area when using the normal transparency mode.
It also can not scan it's entire glass plane because it uses parts of it for calibration purposes.

Kind regards,
Arne