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Jeff_1630
18-Sep-2003, 16:15
Is anyone scanning BW 8x10 neagatives and printing them at a high DPI (between 480-720) on an inkjet printer? How do these compare to contact prints after they've been framed and mounted?

I know the conventional wisdom on digital output says 300dpi printing is enough and that enlargment factor is not a problem with digital workflow (within reason). I have a hard time with both of these. Ctein has writen many times about how he gets more detailed prints on his HP printer at higher dpi with an upper limit of around 600. Paul Roark has also written about getting better results at higher than normal output DPI. I also have a hard time believing that enlargment factor is a non issue in digital output. It maybe miniumized, but it's still a consideration.

Finally, those who ask why, that's easy. My kids can play in my office while I make digital prints, they can't do that in my darkroom.

thanks,

Brian Ellis
18-Sep-2003, 19:38
I occasionally scan 8x10 black and white negatives and print them on an Epson 1160 printer using MIS VM inks. Like you, I've seen lots of different opinions for the optimum print dpi. George DeWolfe says 480 dpi is optimum, others say different numbers. With 4x5 negatives I scan at the maximum ppi I can get with my Linoscan 1400 scanner (1200 ppi) and then print at whatever dpi is produced by that scan at whatever print size I choose. In other words, I don't scale my scans to any particular print size. Since I don't print larger than about 11 x 16 from a 4x5 negative 1200 ppi in the scan always results in a print of considerably more than 300 dpi. Since I'm scanning black and white negatives in 16 bit my file sizes don't get excessively large with this method as they would if I were scanning in color at 48 bits.

However, with 8x10 negatives I do scale the scan to the print size because an 8x10 negative scanned at 1200 ppi would produce a very large file. So I scan 8x10 negatives at whatever ppi is called for by the planned print size and a desired print dpi of at least 300 and preferably 480.

I'm not sure exactly what you mean when you say that some people claim the enlargement size isn't a factor with digital printing. The enlargement factor governs the scan ppi, so the smaller the negative and the greater the print size the lower the dpi in the print. As long as you don't drop below whatever your desired minimum dpi is then you're alright but if your enlargement factor is so great, and the scan ppi so small, that you drop below the desired print dpi then presumably the print quality will be reduced. So at least in that sense the enlargement size is important with digital printing.

Julian_3496
19-Sep-2003, 00:58
Brian, Unless you are using a drum scanner, if you scan at anything other than the full optical resolution of the scanner you are getting interpolated data, as the scanner scans at full optical ppi and then downsizes. To cope with large file sizes you'd be better off IMO scanning at full resolution and the donwsizing in PS. You hear a lot of opinions on the net about some sticky topics like printer resolution. I've talked to a lot of epson techs and they have all said that the desktop printers fudge the data back up to 720 and the large format (7600/9600 etc) fudge the data to 360. As to if they are better than contact prints... I've been using inkjets for the past 3-4 years. For colour, there is no doubt, the Ultrachromes on fine art or RC-type paper are state of the art. For BW the question is more complicated and is akin to a discussionof platinum over silver. For images which need a full tonal range and where the 'beauty' of the print is in the mid/hi tones, inkjet on fine art (hahnemuhle photorag for example) can produce wonderful prints BUT you are spraying ink onto paper and the result will never have the three dimensional 'glow' of a silver print, but then neither will a platinum print. So you can't really compare them with a silver contact print because they are chalk and cheese. The inkjet print will get more tones onto the paper - Jon Cone at Piezo-land states 256 tones, but then an epson driver can only print 25 - but you will loose the depth of the black. MIS do a BW inkset based on Ultrachrome technology that will print on the RC papers like Epson Semi-matte Premium gloss, Ilford matte etc. I've recently been using this with the studioprint rip on a 9600. With the standard epson driver the printer lays too much ink down and you get bronzing, with the rip you can reduce this but the problem remains. Also the tactile quality of the paper is pretty poor. For my own work I waffle between inkjet and darkroom. I recently made some contact prints from 11x14 BW negs onto Ilford warm-tone, and for quality - forget the inkjet. But digital has the advantages of easy dust spotting, finer control of the print etc etc Finally, be very wary of inkjet lists. I've been a member of both the piezo list and the digital print list since its inception and there is a lot of rubbish spoken very loudly. Always do your own testing, listen to the lists for technical advice but don't trust any of it!

Jeff_1630
19-Sep-2003, 08:48
Brian, Julian, thanks for the feedback.

Brian my comment on enlargment comes from the fact that you can read many threads over at our former home about how 35mm scanned at 4000 is the same 4x5 scanned at 1000 dpi. My contention is that for similar quality scanner optical systems the larger film (just like conventional printing) will be better at equal print size. Maybe that's a no brainer for us here, but for many it seems not to be. All of the factors that affect traditional enlargment (diffraction, vibration, ect) are present in a scanning system. They may have less effect, but they are still present.

As for my own digital prints from 8x10, I'll let you know how they look in a few weeks.