DanPhoto@aol.com
Wed, 31 Mar 1999 23:14:58 -0500 (EST)
Hey Adam,
If you want to stay with the 300 lpi digital negs and still get 256
shades of gray, you will indeed an imagesetter capable of at least 4800
dpi output. (Level 3 Postscript apparently changes the rules but let's
just stick to the more common output for now.)
Though a standard linescreen negative will be more sensitive to banding
problems than a stochastic version, if you've decided to go with the
former, you might be well-advised to not get too hung-up on the 256 grays
issue. Most "photographic" images (ones that don't use designer-type
blends) can look perfect with far fewer than 256 grays.
The Lenswork Special Edition prints are made with a 425 lpi negative that
is made on an Agfa running at 3600 dpi. Before you glaze over with math
formulas, let me tell you that combination yields only about 72 shades of
gray! Yet the prints look perfect. Brooks Jensen did run into some
banding problems with certain images that had gentle, clean blend-type
effects. His options were to go with lower linescreen (and risk visible
regimented dots), go with a stochastic dot pattern and risk a visible
grittiness in highlights (visible on silver gelatin but not hand-coated
processes), or find a higher resolution imagesetter.
Anyway, an easy way to see of your image will handle fewer grays is to
use the Posterize command in Photoshop (Image>Adjust>Posterize) and dial
in the number of grays that your linescree/imagesetter combination
provides.
Once you've determined whether you can live with fewer grays at your
chosen lpi, you might find many more service bureaus that can output your
negatives.
Don't know about that humidity thing causing streaks. Last time I had
that problem it was owing to sun spots and athlete's foot.
Hope this helps.
Dan
In your email you stated...
>From: akimball@finebrand.com (Adam Kimball)
>Reply-to: alt-photo-process-l@skyway.usask.ca
>To: alt-photo-process-l@skyway.usask.ca
>Oh no...
>
>Well, after two imagesetters seemed incapable of providing output that came
>anywhere near to approaching my criteria, I finally thought I found a good
>local
>shop. They are a high-end prepress house with a Linotype-Hell Herkules Pro
>capable of 5081 DPI - which would render my 300LPI negs with 256 shades.
>Things
>went well initially as I ouptut some wedges, but my first real negative
>came back
>with VERY fine lines through the film. These lines are probably a pixel
>wide and
>run in the direction of the film through the rollers. David Fokos (who
>helped me
>tremendously) informed me that these lines may be "static" lines - and the
>only
>workable solution is changing the humidity of the room where the imagesetter
>works. Not exactly something I can request being that I spend $100/month
>there!
>Ha. However, if you have another idea about what is going on, I am all ears.
>
>Which brings me to my real question- where do I turn? I'm willing to send
>my work
>out of state if necessary - just as long as I get high-quality results.
>If you
>are doing digital linescreen negs at 300LPI, I'd really love to hear where
>you are
>getting them done.
>
>Much thanks,
>Adam
>
>
>
>----------------------- Headers --------------------------------
>Return-Path: <alt-photo-process-error@skyway.usask.ca>
>Received: from rly-yd01.mx.aol.com (rly-yd01.mail.aol.com [172.18.150.1])
>by air-yd04.mx.aol.com (v59.2) with SMTP; Wed, 31 Mar 1999 20:52:56 -0500
>Received: from skybat.usask.ca (skybat.usask.ca [128.233.1.27])
> by rly-yd01.mx.aol.com (8.8.8/8.8.5/AOL-4.0.0)
> with SMTP id UAA07867;
> Wed, 31 Mar 1999 20:51:26 -0500 (EST)
>Received: from process.sask.usask.ca by sask.usask.ca (PMDF V5.2-31 #35001)
> id <01J9HQ28404G9FMJD6@sask.usask.ca>
> (original mail from akimball@finebrand.com); Wed, 31 Mar 1999 19:51:08 CST
>Received: from mail6.sirius.com ([205.134.253.139])
> by sask.usask.ca (PMDF V5.2-31 #35001)
> with ESMTP id <01J9HQ26ZY6G9FMJS5@sask.usask.ca> for
> alt-photo-process-l-expand@process.sask.usask.ca
> (ORCPT rfc822;alt-photo-process-l@skyway.usask.ca); Wed,
> 31 Mar 1999 19:50:53 -0600 (CST)
>Received: from frank.finebrand.com (IDENT:root@[207.44.234.9])
> by mail6.sirius.com (8.9.1/8.9.1) with ESMTP id RAA07601 for
> <alt-photo-process-l@skyway.usask.ca>; Wed, 31 Mar 1999 17:50:51 -0800 (PST)
>Received: from finebrand.com (sgigate.SGI.COM [204.94.209.1] (may be forged))
> by frank.finebrand.com (8.9.1/8.8.7) with ESMTP id RAA29245 for
> <alt-photo-process-l@skyway.usask.ca>; Wed, 31 Mar 1999 17:49:56 -0800
>Date: Wed, 31 Mar 1999 17:49:58 -0800
>From: Adam Kimball <akimball@finebrand.com>
>Subject: Trials and Tribulations of the Digital Neg.
>To: alt-photo-process-l@skyway.usask.ca
>Reply-to: alt-photo-process-l@skyway.usask.ca
>Message-id: <3702D0C6.27F7298@finebrand.com>
>MIME-version: 1.0
>X-Mailer: Mozilla 4.5 [en] (WinNT; I)
>Content-type: text/plain; charset=us-ascii
>Content-transfer-encoding: 7bit
>X-Accept-Language: en
>References: <6f0a59f3.3702bb29@aol.com>
>Comments: "alt-photo-process mailing list"
>
This archive was generated by hypermail 2.0b3 on Sat Nov 06 1999 - 10:09:05