I doubt you'll find many shots over 300 dpi, unless it's some sort of government or library archive. Beyond 300 dpi, file sizes tend to be very large, with very little gained in the resolution you actually can see. I've gone down to 150 dpi on large prints without much degradation of the image. That's a 20 x 13 print from a Nikon 6 mpixel image. Most magazine print stuff is in the vicinity of 200 to 240 dpi. This makes transmission to remote print sites faster. Of course, some use higher dpi, but not as much as you might think.
My scanner came auto set on 200dpi. I've use higher only for special projects. I remember seeing many websites offer links to higher res versions of the pics featured but most seem to have gone away from this. File sizes just get way too big to be useful.
I can scan from 50 dpi clear up to 12,800 dpi and I often scan at 600 dpi to get a very high quality image that I can scale back later. What are you looking for specifically and maybe I can produce you and image or two at these higher dpi settings. As mentioned above most websites don't use images at high dpi settings do to space requirements. :lightbulb: :lightbulb: :lightbulb: :lightbulb:
I do scan slides at very high resolutions. That's because they are roughly 1-inch by 1.5 inches (24mm x 36mm), and I'm going to blow them up to at least 8 x 11.5 inches, and perhaps 13 x 19 inches. For a 13 x 19 print at 300 dpi I need to scan at about 4000 dpi.
Hey mates, I work in a brazilian rail magazine, and the pictures is never good enough. Beacuse of the resolution i mean. We got two sections that requires big picture in very high resolution cause its two pages open. We got some stock of photos but now i am looking for more. The pictures must be in 300 dpis 42 x 28. Its so hard to get these babes... Hope you can help me, MP
When I scan at very high resolution it is because I want to zoom in on specific detail and crop out most of the image anyway.
To us Americans, that's a two-page spread which measures 11 x 17 inches. I think commercial photo bureaus are the only places you might find images of that size and resolution. That's 16.8 megapixels. Professional digital cameras are just reaching that range, so most train images today will be scanned from prints or slides, rather than directly from the camera. I'm finding I can print a 6 megapixel image at 11 x 17 inches very well. Yes, it's only 180 dpi, but if the image is sharp, it reproduces very well in print. These images might be easier to find. I am also going from a digital camera directly to a high-quality digital printer, with no screening involved. When there is screening, resolution can drop quickly, unless the screening process is very tightly controlled. I've been very disappointed with the digital plate-making processes in the US. The results are muddy and not sharp because the registration between CMYK is not good, and the gamma is often distorted.
you're right, i forgot about the measures. my apologies are you sayin that digital cameras still cant take pictures in 300 dpi who measure 42 x 28 centimetres? it doenst have to be a 16.8 megapixels camera to make those pictures
It does have to be 16.8 MP to get a 300dpi, 42x28cm photo. Perhaps you can get by with lower dpi or smaller size, but math is math. 12MP is the current leading-edge standard for production digitals. This yields a photo size a fair bit less than 11x14 (28x36cm) at 300dpi.
Many years ago, in the mid-80s, I wrote a two-part primer on resolution for Computer Graphics World. This was when the very first digital laser printers were being introduced at a price of $20,000. And they were black&white! I doubt I can dig that up in a digital form, although I wrote it on a computer, a $15,000 Burroughs B20. A few years back, perhaps 2003, I wrote another primer about resolution, to train government employees about what's required for a good image. I might be able to find that. http://www.kenrockwell.com/ has a lot of good stuff about this issue. I'm in his camp that mega-pixels aren't everything. He writes about exactly the same subjects I've been writing about since the 1970s, and in more depth, though a little less science. I thought I'd also posted something here on Trainboard, but can't find it. It treated stages of printing since I got involved in the 60s. I used analog (A) and digital (D) as dividing points. Film (A) to Screening (A) to Negatives (A) to Plates (A) to Press (A) Film (A) to Scanner (D) to Negatives (D) to Plates (A) to Press (A) Digital (D) to Negatives (D) to Plates (A) to Press (A) OR Film (A) to Scanner (D) to Plates (D) to Press (A) Digital (D) to Plates (D) to Press (A)--may have improved Digital (D) to Digital Press (D)--prices coming down? I may have forgotten a few intermediate developments, and I haven't followed printing technology for the past few years. I went digital camera to digital press for my 11 x 17 inch book on Alaska. I've been in printing since 1967, and believe the results were as good as anything I've seen. And this was done with a 6 mega-pixel camera, a D100. The D70 promises even better results. I haven't laid out the second edition, but the 13 x 19 prints are spectacular.
