[pure-silver] Re: Digital Negatives from Imagesetters
- From: "Ralph W. Lambrecht" <info@xxxxxxxxxxxxxxxx>
- To: PureSilverNew <pure-silver@xxxxxxxxxxxxx>
- Date: Fri, 14 Apr 2006 01:06:04 +0200
Sorry to hear about your troubles. I had no such problems. Your description
sounds a bit odd to me, I'm not even familiar with the terms you used (not
in combination with halftones and imagesetters anyway).
Here is how I do it:
1. Get the image on the screen to your liking.
2. Boost or reduce it to 450 dpi at full print size.
3. Run the transfer function I supply on my website.
4. Invert the image and save it to a CD.
5. Take it to the service bureau and ask for a film at 3,600 dpi with a 225
line screen, emulsion side up.
Result: a superb halftone, invisible to the naked eye, no banding, no
mottling, and when contact printed on MG-IV-FB paper, matching the screen as
much as technically possible.
Regards
Ralph W. Lambrecht
http://www.darkroomagic.com
On 2006-04-14 01:17, "Claudio Bonavolta" <claudio@xxxxxxxxxxxx> wrote:
> Ralph W. Lambrecht a écrit :
>
>> To whom it may concern.
>>
>> I have reorganized the 'Library' section of my web page. While doing so,
>> I've added a digital step tablet, a process checker and a Photoshop transfer
>> function for digital negatives from imagesetters with brief instructions.
>>
>> The system work very well and produces high-quality FB prints from digital
>> files. As always, downloads only for your own private use.
>>
>>
>>
>>
>>
>> Regards
>>
>>
>>
>> Ralph W. Lambrecht
>>
>> http://www.darkroomagic.com
>>
>>
>>
> Thanks for your contribution Ralph.
>
> A couple of weeks ago, I finally found an imagesetter in my area (Geneva
> - Switzerland), which wasn't that easy because they're all going CTP
> (Computer-To-Plate) now.
> So I designed a step tablet in Illustrator (using only the black
> channel) with a 2% increment between each step and a 1% for the darkest
> and lightest steps, added a 4000dpi scan of a 35mm TMX film converted to
> a 8-bits gray scale and a pair of the common USAF1951 test target. I
> then converted it to a negative without applying any curve (the
> objective was to trace the curve ...).
> You can find it on http://www.bonavolta.ch/hobby/en/photo/digineg.htm
>
> I went to the service bureau, had to re-explain 3 times what I wanted to
> do (I much better understand why extra-terrestrians avoid any contact
> with humans) and we finally agreed for an A3 digital neg made with a
> 20-microns diffusion pattern obtained directly from the AI file.
> I suppose the 20-microns is the dot size. The finest size they can do is
> 13-microns and that's probably what I should have asked.
>
> I received the neg the next day and printed it around 2:00AM (I couldn't
> sleep anyway ...).
> Result is disappointing: contrast is very high but this was expected and
> can be adjusted, print is really grainy and this isn't the TMX grain,
> but the worst, because I don't know how to cope with them, are banding
> and some mottling in uniform areas, already visible on the digineg.
> A pair of articles on how imagesetters work and their features which may
> explain part of the problems I've had:
> http://www.exxtra.com/imagesetters/whybetter.html
> http://www.initpress.ru/eng/stat004.htm
>
> I'll try to apply your transfer curve and ask for the maximum resolution
> but I'm afraid banding and mottling will remain.
> Finding a good service bureau seems harder than the Graal's quest ...
>
> I'll be out for Easter and only be back next Tuesday.
============================================================================================================To
unsubscribe from this list, go to www.freelists.org and logon to your account
(the same e-mail address and password you set-up when you subscribed,) and
unsubscribe from there.
Other related posts:
