[filmscanners] Re: HP PhotsSmart - questions

["Arthur Entlich" <artistik@shaw.ca>]

Hi Rich,

Unlike probably most of the people on this list, I actually owned a S10,
and an S20 (the USB uprage version), and also did a survey on them,
because they were a pretty problematic product.

Firstly, I would probably NOT try to clean the unit, unless you know for
a fact it is dirty (you may notice halos around brighter objects or
other high contracts transitions on slides or negs).

The reason I suggest against it is because this scanner is a highly
complex device mechanically.  It has a stage that transforms itself from
being a reflective scanner (for up to 4x6" prints at 300 dpi, to a
transmissive slide to negative without carrier scanner.  Each use
request the stage to alter the design of the input slot, and it is
literally done with movement of cams and gears and mirrors.

The actual ppi/dpi this scanner produces is considerably lower than the
maximum 2400 it claims in transmissive mode, due to the nature of the
optics and focus, and perhaps the CCD itself.  I believe it was tested
at about 1000 ppi/dpi in highest transmissive mode (slide/neg).

The problems with it include banding in the scan, interference in the
scan showing up as a herring bar pattern or concentric rings looking
like newton rings, noisy shadows, high grain aliasing (creating the
appearance of grain in scans where it may be smaller than that in the
original, due to the resolution of the scanner), and off color
especially in the reds.  It also has been known to get confused as to
which mode it is in, and the mirror can position incorrectly causing a
hazy off register green shadow in the image.  It suffers from color
fringing, and can, on some models scratch the sixth frame of a film stripe.

It is a good starter film scanner for email and lower resolution use.

As to why the 150 ppi/dpi looks better than the 300 ppi/dpi, it is
probably because the 300 dpi (maximum in that mode) requires the image
be processed with unsharp masking to return some of the lost detail.

There are mathematical reasons for this having to do with sampling
errors. It is normal for scanners to do this, and the final result once
unsharp masking is applied should give you better results than the 150
dpi version.

However, if you are going to only scan reflective images, you would be
better off getting a flatbed scanner.  They can be had very
inexpensively new and even less used. Although most snapshots probably
only contain about 200-250 ppi/dpi resolution, flatbeds offering 600
ppi/dpi will probably be able to capture the complete detail in the print.

Art




rkoziol3@comcast.net wrote:

> Hi,
>
> Been reading the posts here for quite some time.  Just got into
> scanning.  In fact the recent thread on Cheap Film Scanners woke me
> up :-)  I have one that's at the bottom of that heap.  It's HP
> PhotoSmart vintage 1997.  SCSI interface, which makes it S10 I guess.
>
> I'm using the current version of HP software from their Support site.
> Did a calibrate with a white piece of paper (the card is gone). The
> scanner was donated by a friend.
>
> Now the question.  I started with a simple color print (3x5) scan and
> noticed that setting it to 150dpi gives a "sharper" result than
> 300dpi.
>
> Can that be explained in any way?  Saved as bmp and jpg, same
> results.
>
> Secondly, should I take the scanner apart and attempt to clean any
> optical components?  I'm quite handy with small tools :-)  After
> sitting for so many years and some usage by the previous owner, it
> must have some film whatever the optical pickup is.
>
> Regards,
>
> Rich Koziol
>
>

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