RE: Questions about Genuine Fractals

["Laurie Solomon" <laurie@xxxxxxxxxxxxxx>]

Byard,

I have only used the Genuine Fractals version of the application which
supports RBG only and not the PrintPro version which supports CYMK; but I
assume what I will say will hold for both.  There may be service bureaus and
labs that will accept the GF .stn file format; but most do not do so and
require the file be supplied them in usually an uncompressed .tif format.
Even if they do accept the .stn format directly, you would need to specify
the image size you wanted the file printed to and the resolution to use for
that size ( as well as to maintain aspect ratios or not) so that the lab or
service bureau would know how to decode the .stn file.  The final resolution
of course would be determined by the demands and optimum resolution required
by the printer in question.

Thus, you would probably need to maintain the .stn file as a archive source
file which you would then open and save as an uncompressed .tif file with
the image having been decoded to the desired size and aspect ratio as well
as resolution that your large format inkjet printer will accept and
requires.  The advantage of the .stn format is that you can keep one
archived source file which can be decoded as needed to fit the desired sizes
and resolutions on a case by case basis.

I have heard of the incremental upsampling interpolation technique; but I
have never used it.  One of the potential problems is that their is always
the possibility of producing to a greater degree artifacts with each
incremental upsampling since you will be creating interpolated samples from
previously interpolated samples where an artifical bit of interpolated data
is them taken as raw data and artificialy interpolated again.  It might be
less dangerous to do the up sampling in a single interpolation than in
multiple incremental ones.  I believe, arguably so, that GF tends to shine
when it comes to enlarging and upsampling at large to very large sizes when
compared to Photoshop's Bicubic interpolation method.  At smaller sizes,
they are about the same.  As for some of the other methods and programs for
interpolation and upsampling, I cannot advise since I have not used them and
am not familiar with them.

Another problem with incremental upsampling of a file is that you would have
to maintain an archived copy of the incrementally interpolated file for each
use you that you intended it to be used in each image size and resolution
that you would be potentially wanting to reproduce in printed form; or you
would have to do the incremental interpolation anew each time for each use.
This is not the case with GF where you only need to maintain a single
encoded .stn file.

While I do not think that I have given you the unequivical answer that you
might have liked, I hope that I have given you some things to take into
consideration.  In the end, you will still have to pays your money and take
your chances by trying it out yourself with your setup and slides.  I have
found it to be faster than using Photoshop to do incremental upsampling
would be, to do a good job especially at large and very large sizes from
35mm slides, and to produce few if any artifacts.  However, you need to
remember that in order to do a high quality jopb with minimal artifacts one
should not use the unsharp mask on the saved archival source encoded .stn
file but only on the decoded file just before sending it to the printer.

Hope this has been helpful.  I am sure that others will have a different set
of experiences and findings.

-----Original Message-----
From: owner-scan@leben.com [mailto:owner-scan@leben.com]On Behalf Of
byard pidgeon
Sent: Wednesday, April 24, 2002 8:19 PM
To: scan@leben.com
Subject: Re: Questions about Genuine Fractals


OK Laurie, I'll try to clarify...I am trying to ascertain whether GF will do
what I will be needing to do: allow me to make large format giclee prints
from 35mm slides (larger than one could expect to do without
interpolation/enlarging).

Is GF a better solution than making several incremental up-interps in
Photoshop, for instance? (My large format instructor, who made gorgeous
prints on older gear, used incremental PS interpolations).

Color management shouldn't be a problem, as I will be working in my own
system, initial input through final output.

I'll buy GF if it will do a better job...don't have it yet.

Thanks again


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