inconsistant output size

[edarobinson]

I am finding that the scanned image size in photoshop is usually smaller than the output size displayed in SilverFast 6 (1-6 pixels in height and/or width difference.) This is a hassle since I am scanning a digital slide show and need the images a specific size. Any suggestions?

Setup in SilverFast: original size=output size (scaled 100%) at 1333dpi.

Thanks,
Ed Robinson

[Gregory C]

Setup in SilverFast: original size=output size (scaled 100%) at 1333dpi.

It's only a guess, but SilverFast may be using Interpolation to produce your final files.

If you haven't already, try using the Resolution slider to set the resolution rather than typing it directly into the field. When you use the slider to select a resolution, you are in fact selecting a hardware-supported resolution and you are telling SilverFast to not use interpolation in the process. The exception for this is the highest resolution allowed by the slider which may be double that of the highest hardware-supported resolution.

Note that even if you specify a hardware-supported resolution within the resolution field, SilverFast will still use interpolation to produce the final scan. You must use the slider to select the resolution and turn interpolation off.

Let us know how this turns out for you.

[ianders1]

After following Gregory's advice in choosing a hardware scan resolution, do the following:

If you want an image to be an exact size in pixels, the best way to do this is to go to the Frame tab, click the units until it says pixels, then enter the exact dimensions. After that, click on both Lock icons to make them closed. Then no matter how you resize the frame, it will always be that pixel size upon output, whether it be 100% or 102%.

I've used this method to scan in many "slide-show" graphics myself.

-Ian A

[edarobinson]

Thanks for the feedback and suggestions. Unfortunately I have not found a simple solution, more likely I have found a bug or a feature request.

I believe the problem is not interpolation, but rather averaging when SF runs the original->scale %->output calculation. I find that I can change the original size by one, two or three pixels without changing the output size. Making these manual changes through trial and error I can "discover" the correct original size to output to the size I require.

I think the reason I never noticed this before is because I usually scan at maximum size/resolution where the difference between original size and output size is not as great as when I am scanning smaller files.

My only other question.... is this unique to my system, or is it that the rest of you just have not noticed?

Thanks again.
Ed Robinson

[Gregory C]

Fixed for v6.0.1r23.

regards
Gregory

[LSI_Noack]

To check whether SilverFast needs to interpolate, you want to use the DPI box.

Usually, the value displayed represents the output value of the resulting scanned image file.

If you are pressing the CTRL key, the hardware resolution of the scanner that will be used for that given scan is shown.

If you now press Shift+CTRL and the value changes again, interpolation will occur.