On: Fri, 2 Jan 2004 Jonathan Coleman wrote:- >> Re: >> My understanding re inkjets is you can output at 1/3rd the printer >> resolution. So, if printing at 720, you can comfortably come down to 240. > > This is interesting. For over a year, I prepared images at 300 dpi for > output to my Epson 7600. Although I was happy with the results, I always > felt that the larger images were reaching the limit of what was possible.
Thinking out loud.......what were you comparing your results with? > Then I read on this List that the optimum output res for inkjet was 360 dpi. > This made a lot of sense being exactly divisible into the 1440 x 720 dpi the > printer uses. On a 1440dpi printer you will see little difference above 360dpi. > The consequence of moving up those extra 60 dpi is a dramatic increase in > print quality. The images seemed richer, with more `punch`, and sharpening in > PS 7 had much more impact. This is due to eliminating a resolution clash between the printer and the file which results in interference with the printers dithering pattern giving an apparent lack of visual sharpness plus jaggies on diagonal lines. Most 1440 dpi machines are actually 720dpi machines doing a double pass of the head with corresponding changes in the differing pattern to give a true 1440dpi resolution. Each ink nozzle is capable of laying down a maximum of 180dpi squirtsworth of ink...multiply that by 4 to give 720 x 2 passes = 1440dpi.....so exact fractional multiples of 720dpi will give the best results. > It will be interesting to see if 240 dpi sees no degradation from 360 on, > say, a 30 x 24 print. If so, then I can once again enjoy smaller file sizes > AND max quality. Sounds too good to be true!! Which brings me to suggest that it is entirely possible to get excellent results at 180dpi....or even 90dpi - depending upon print viewing distance AND most crucial of all, the pre-print sharpening routine employed. A lot of digital workers confuse themselves about sharpness, and I hear plenty of talk about this and that sharpening plug-in giving fantastic results. Well, fantastic compared to what? - we may ask. Sharpness is an optical illusion which either works ..... or not works. A 'properly' sharpened picture does not look like it has been sharpened - it just looks sharp and naturally so to the eye. I know that sounds like an oxymoron and it is, as a mastery of the arts of illusion takes some doing and commitment. Tip: You can always print out sharpening 'test-strips' to see what an individual picture looks like on inked paper with varying degrees and types of sharpening routines to choose from before a costly final print-out. William Curwen =============================================================== GO TO http://www.prodig.org for ~ GUIDELINES ~ un/SUBSCRIBING ~ ITEMS for SALE
