DIRTY HARRY wrote:
I use an Epson Perfection 1200U photo flatbed scanner with a slide/ negative attachment. This scanner will allow me to scan up to 4X5 slides and negatives: however, the best resolution I can do on this old baby is 1200 dpi. I've been told that I should get my 35 mm slides scanned at 4000 dpi but just being an amateur and just fooling around as a hobby I don't know that I want to spend the time and money to do that. .One question I do have is I have some 2 1/4 squarer (6X6 whatever) color negatives (took them with my C330 when I still had it) that I have scanned on this scanner do you think 1200 dpi is good enough for those photos?
I use an Epson Perfection 1200U photo flatbed scan... (
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A nominally 2-1/4 square or 6x6 negative is actually 56mm square. That's the 2.205 inches we need to multiply by 1200 dpi to determine the pixel dimensions of an image scanned at 100%.
2.205 x 1200dpi = 2646 dots, which become 2646 pixels in the resulting file. (Remember, scanner dots and digital camera sensels have dimensions. Pixels have color values only. You can reduce and enlarge pixels to create output dots, later.)
The minimum number of file pixels you need to spread over every inch of printed output depends on the viewing distance. MOST labs and graphic arts printers will tell you, if they are honest, that an 8x10 inch image needs 240 original, from-the-camera or from-the-scanner pixels to spread over every inch of the print. They might ask for 300 PPI, because that contains a fudge factor for making *smaller* prints, but the typical human being cannot resolve more than 240 pixels per inch at 12.8 inches (the diagonal dimension of an 8x10, which is the normal closest viewing distance for an 8x10 print), no matter how many dots per inch are used to reproduce them.
Okay, knowing THAT, we can say that the diagonal of a print can be found by Pythagorean Theorem, or A squared plus B squared equals C (hypotenuse, or diagonal) squared.
Let's assume you crop a little less than a quarter inch on all sides, so the left-over scanned image is 2400x2400 pixels. Divide that by 240 PPI and you get a 10x10 inch print. Divide that by 300 PPI and you get an 8x8 inch print.
In many instances, you might make a larger print, via interpolation, but that would depend upon how close you expect someone to "pixel peep" it. So long as you view the print from its full diagonal distance and no closer, you can keep blowing it up from 10"x10" at 240 PPI, and it will appear equally as crisp — again, ONLY at a distance equal to the diagonal dimension of the print. Getting 13" away from a 40x40 inch print made from the same scan (60 original scanner file PPI interpolated to 240 PPI input to the printer driver) may let you see the actual pixels as slightly fuzzy, jaggy stair steps.
My take on this is that your scanner is sufficient to make scans from 6x6 format negatives that will enlarge to 10x10 inches when printed from nearly the full negative area.
35mm is a different story. A full frame 35mm negative is going to scan at about 22x34mm. That is .866 by 1.3 inches. Scanning at 1200 dpi, you get a *file* of about 1040 by 1560 pixels. Divide by 240, and you get a print size of 4.333 by 6.56 inches (realistically, a 4x6 print).
So... If all you want are small prints from 35mm, and 8x8, 8x10, or 10x10 from 6x6 format, then keep your scanner.
If you want something better, spend $180 to $190 on Amazon for an Epson V600. It will vastly expand the size options, PLUS, it has Digital ICE (a package of technologies that remove dust and scratches, attempt to restore original color balance, and more).