DIRTY HARRY Loc: Hartland, Michigan

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?

jerryc41 Loc: Catskill Mts of NY

As soon as anyone posts "dpi," you know that will become a topic of "discussion."

You can experiment. Try low res and try high res. See what you think of the results.

http://howtoscan.ca/scanning-tips/best-slide-scan-resolution.php
http://www.rideau-info.com/photos/scanning.html
https://www.pcworld.com/article/2011344/preserve-all-your-precious-images-the-right-way.html
https://www.scanyourentirelife.com/qa-whats-best-dpi-or-resolution-scan-your-film-negatives/
http://www.digitalmemoriesonline.net/scan/scan_processing/resolving_scanning_resolution.htm

kcooke Loc: Alabama

This might be a bit dated but it may be worth reading.

https://kenrockwell.com/tech/scanner.htm

burkphoto Loc: High Point, NC

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).

Cany143 Loc: SE Utah

Scanning is as much an art (or craft, or science) as in camera shooting is. Optical resolution, software interpolation, D-Max capabilities or limitations, native and/or 3rd party software capabilities, etc., contribute as much as the math associated with dpi, neg or slide size or format, or the intended result and/or use does. The biggest problem most face is that generally, one wants to scan hundreds --or thousands-- of images, and working in bulk may render reasonable results, but those results are rarely ideal. Here's another vote for the Epson V600, but any (modern) scanner will do if its used well.

Gitchigumi Loc: Wake Forest, NC

I am following this thread as I have a couple of large storage tubs full of old slides, prints and negatives. In looking at them, though, most would not benefit from super-res scanning. These were taken over the past 40 years or so and, frankly, aren't all that clear, sharp or colorful any more (assuming they were 40+ years ago!). They are meaningful to me and fun to look at, but I'm afraid no one else would find them of value.

Given all that, I would think the lower resolution would be acceptable. No need in the max possible res scan of a not-perfect image! 😳

DIRTY HARRY Loc: Hartland, Michigan

Not sure I can justify spending nearly $200 to scan the few negatives and slides I'd be interested in doing plus I don't shoot film anymore and then there is the question of how many photos I will print much larger than an 8X10. Is there a processor who I may send some of my 120 format color negatives to to digitize at a reasonable cost. To me photography is a hobby, I retired from automotive engineering 15 years ago and I'm not looking for a new job. One thing I would like to know is how do megapixels relate to dpi and film size (35 mm & 120 formats)? I have and Olympus C3030 3.2MP, an Kodak Easyshare C183 14 mp, and a Canon T2i 18 Mp cameras that I'm sure I haven't used all of the capabilities on yet. How do these relate to my C330 (120 format) or Minolta XD11 (35 mm format) ?

cambriaman Loc: Central CA Coast

I would get the new Epson scanner and be sure I got quality scans. The 35mm images scanned at 1200 dpi won't be very defined.i

gwilliams6

jeryh Loc: Oxfordshire UK

That is the standard DPI for 6X6; I scan all my 6X6 trannies at that resolution.

DIRTY HARRY Loc: Hartland, Michigan

Sorry, I don't understand your comment.. what is the standard DPI for 6x6?

burkphoto Loc: High Point, NC

There is no standard! There is only a calculation process.

You first determine the largest size print you need to (or might) make. Then you multiply THAT by the number of original, scanned (or from-the-camera) pixels you want per inch (at least 240 for an 8x10, and as high as 360 for a smaller print, and as low as 180 for large prints). The result is the number of DOTS you need to scan. For instance:

I want to crop a 20x16 of a LARGE group of people out of a 6x6 negative. So 20 x 300 (my usual resolution for a 16x20 of a large group of people with small heads) is 6000. 16 x 300 is 4800.

I need an image 6000 x 4800 pixels. So I need to capture about 2" x 2" of the 6x6 negative. Always start with the long dimension... 6000/2 is 3000. So... I'm going to set the scanner for 3200 dpi for that scan. I'll get some more pixels than I need in the file, but it will work! I can fit my image into a 20x16 inch crop with pixels to spare.

gwilliams6