From mboxrd@z Thu Jan 1 00:00:00 1970 X-Msuck: nntp://news.gmane.io/gmane.comp.tex.context/15824 Path: main.gmane.org!not-for-mail From: Siep Kroonenberg Newsgroups: gmane.comp.tex.context Subject: Re: ConTeXt output & commercial printing houses: Thanks! Date: Tue, 27 Jul 2004 11:27:12 +0200 Sender: ntg-context-bounces@ntg.nl Message-ID: <20040727092712.GA5184@mol> References: <20040724194138.GG18318@swordfish> <001501c4722e$4ca1f100$fcb359d5@DJCPX90J> <20040724194138.GG18318@swordfish> <0A30D0B7-DE21-11D8-9127-0030659899AA@fiee.net> <20040724194138.GG18318@swordfish> <20040724152139.36ca8b80@atipa.local> <20040724202504.GA9909@muisje> <20040724194138.GG18318@swordfish> <20040724152139.36ca8b80@atipa.local> <4.3.1.2.20040726232423.017f84f8@cits1.stanford.edu> Reply-To: Siep Kroonenberg , mailing list for ConTeXt users NNTP-Posting-Host: deer.gmane.org Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii X-Trace: sea.gmane.org 1090920518 14400 80.91.224.253 (27 Jul 2004 09:28:38 GMT) X-Complaints-To: usenet@sea.gmane.org NNTP-Posting-Date: Tue, 27 Jul 2004 09:28:38 +0000 (UTC) Original-X-From: ntg-context-bounces@ntg.nl Tue Jul 27 11:28:28 2004 Return-path: Original-Received: from ronja.vet.uu.nl ([131.211.172.88] helo=ronja.ntg.nl) by deer.gmane.org with esmtp (Exim 3.35 #1 (Debian)) id 1BpOG3-0003qQ-00 for ; Tue, 27 Jul 2004 11:28:27 +0200 Original-Received: from localhost (localhost.localdomain [127.0.0.1]) by ronja.ntg.nl (Postfix) with ESMTP id 9062412783; Tue, 27 Jul 2004 11:28:27 +0200 (CEST) Original-Received: from ronja.ntg.nl ([127.0.0.1]) by localhost (ronja.vet.uu.nl [127.0.0.1]) (amavisd-new, port 10024) with LMTP id 09417-01; Tue, 27 Jul 2004 11:28:27 +0200 (CEST) Original-Received: from ronja.vet.uu.nl (localhost.localdomain [127.0.0.1]) by ronja.ntg.nl (Postfix) with ESMTP id 5642C12789; Tue, 27 Jul 2004 11:25:52 +0200 (CEST) Original-Received: from localhost (localhost.localdomain [127.0.0.1]) by ronja.ntg.nl (Postfix) with ESMTP id AC80E12789 for ; Tue, 27 Jul 2004 11:25:51 +0200 (CEST) Original-Received: from ronja.ntg.nl ([127.0.0.1]) by localhost (ronja.vet.uu.nl [127.0.0.1]) (amavisd-new, port 10024) with LMTP id 09137-05 for ; Tue, 27 Jul 2004 11:25:51 +0200 (CEST) Original-Received: from dep.oprit.rug.nl (unknown [129.125.36.9]) by ronja.ntg.nl (Postfix) with ESMTP id 1F52B12783 for ; Tue, 27 Jul 2004 11:25:51 +0200 (CEST) Original-Received: from client44-3.kabelA.oprit.rug.nl (GN-HE001-COM03-200-159.kabela.oprit.rug.nl [129.125.200.159]) by dep.oprit.rug.nl (8.12.10.Beta2/8.12.10.Beta2) with SMTP id i6R9PmS1003671; Tue, 27 Jul 2004 11:25:48 +0200 (MEST) Original-Received: by client44-3.kabelA.oprit.rug.nl (sSMTP sendmail emulation); Tue, 27 Jul 2004 11:27:12 +0200 Original-To: mailing list for ConTeXt users Content-Disposition: inline In-Reply-To: <4.3.1.2.20040726232423.017f84f8@cits1.stanford.edu> User-Agent: Mutt/1.4.2.1i X-Virus-Scanned: by amavisd-new at ntg.nl X-BeenThere: ntg-context@ntg.nl X-Mailman-Version: 2.1.5 Precedence: list List-Id: mailing list for ConTeXt users List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: ntg-context-bounces@ntg.nl X-Virus-Scanned: by amavisd-new at ntg.nl Xref: main.gmane.org gmane.comp.tex.context:15824 X-Report-Spam: http://spam.gmane.org/gmane.comp.tex.context:15824 On Mon, Jul 26, 2004 at 11:33:03PM -0700, Brooks Moses wrote: > At 11:15 PM 7/26/2004, you wrote: > >On Sat, Jul 24, 2004 at 03:21:39PM -0500, Bill McClain wrote: > > >> The printer > >> expects CMYK images (not RGB!) where the resolution is approx. 2 times > >> the screen count in the final print, @ the physical size on the paper. > >> So if you have an image in your PDF that is 10 cms /4 in. wide, and you > >> want it printed in a 150 lpi (lines per inch) screen, make sure the > >> original resolution is 300 dpi @ 10 cms / 4 in. > > > >Now that's interesting. I imagined you would get the best results with > >images that were designed exactly at the printer resolution. > > You might, but that would only be true if you also have the image aligned > exactly with the printer resolution -- which is unlikely to be the case > unless you do it explicitly. Having the 2x-or-higher resolution means that > the downsampling in the printing process will produce an acceptable result > no matter what the alignment is. > > Beyond that, I suspect there are also some effects involved in the fact > that the printer is creating a screen rather than dots of pure color; there > are things going on in the screen that are on a finer scale than the line > spacing, and having the higher-resolution to base them on probably produces > a better result. > > - Brooks For a screened picture, you can often get away with less than twice the lpi, especially if there are no sharp transitions. On the other hand, pure black-and-white line drawings are best printed without screening. For such images, higher resolutions are better. 600dpi is enough for losing jaggies. Up to a point, more is better, but printer resolution (2400dpi or more) would produce very large bitmaps. -- Siep Kroonenberg