# Re: HP Photosmart R032 problem

Ewald R. de Wit (ewald@pobox.com)
Tue, 16 Mar 1999 16:34:09 +0100

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john allen pitney (pitney@students.uiuc.edu) wrote:

> $ xscanimage [program starts, I choose /dev/scanner]
> Preview Window [window appears]
> [feed slide to PS, PS pulls in the slide a few mm]
> Acquire Preview [preview acquired as slide feeds *into* the PS]
> [preview looks okay, needs a lot of gamma correction 1.0 -> 2.2 or so]
> [slide is now *inside* the scanner]
> Scan [image is acquired as slide is pushed back *out* of the scanner]
> [so far, so good]
> Acquire Preview [again]
> [this time, the preview is acquired and the slide returns to its
> *out* position, unlike the first time]
> Scan [this time, the slide feeds slowly back into the scanner, then
> immediately reverses direction, and *then* data is acquired. Also, I
> believe this is where the few mm of slip occurs.]

This is normal behaviour for this scanner, it also happens with the
HP windows software. Vuescan doesn't do a second pass over the slide
(or strip) as it scans everything at once - perhaps that's why you
haven't noticed this particular behaviour before. The stupidity seems
to be internal to the scanner.
> Also, my test slide is a fairly typical scene, albeit without any sky
> showing. I find that the default straight gamma curve results in a very
> dark image--to fix it with gimp's levels tool, I need to set the white
> point to 153 (out of 255) and the gamma to about 2.50. Of course, the
> image gets reduced to something like 5 bits of precision after that kind
> of rough treatment. Does this mean the R032 is going to require a
> downloaded tone map just to produce a decent image?

For dark slides, increase the Exposure Time to for example 300% and
apply a gamma of 2.2 if you have a PC monitor.

About tonemaps, I feel it is better to do this in software (on the
frontend side) instead of implementing it for every backend.
Adding some intelligence or densitometric data to the frontend will
benefit all scanners and not just the Photosmart.

> Last night, I tried looking at a log file produced by VueSmart. I put
> some up at the following URLs:

I don't know of any interesting SCL options that this scanner could
still have and that's not incorporated into the newest backend
already. What is it that you are looking for in the vuesmart logs that
you like to have?

    --
      --  Ewald

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