Railfan Technology > Scanning sides and prints for publication

When scanning slides and prints to burn onto a CD and send to national RR publications, what DPI should be used to make the scans? What should the dimensions of the scans be?

From reading technical manuals regarding scanning slides and prints I am totally confused. When uploading images taken with a digital camera the preferred DPI is 300, and the preferred width is 12 inches. However some of the manuals suggest that the scans be 4,800 DPI for good reproduction.

Why is there such a difference in DPIs?

Many thanks in advance. Any tips for scanning would be welcome.

Seaboard

If the publication would want to crop and enhance an area, some extra DPI would help. If you want put several resolutions on a DVD and send that to them.

Back in the days before digital they usually wanted to do the scans themselves. A lot of times some of then would be a long time returning your originals.

Bob

Well, the problem is, they DON'T return the originals. Twice recently some of my oldest and most interesting slides, which were solicited, have been "misplaced". This was a few months ago, so the chance of them ever being returned is very unlikely. You'd think a major publisher would have a better system of tracking slides, and then returning them after the article ran.

So, I bought a scanner, and will never mail original slides to any publisher. If the scans aren't good enough for publication, then that will be their problem.

Seaboard

First of all, why are you going to copy scanned files to DVD to send? That seems archaic to me. But to your question. Scan slides at the highest possible resolution setting and save file as a TIFF. For me, that's about 4,000 dpi rendering a file size of about 165meg per pic. That is large. Large enough to render a nice printed version. I save the scan to a dedicated external drive and also my my cloud backup vendor. For that I use I-cloud, and Dropbox. So, I have it backed up twice. You can create a free account at Dropbox which gives you up to 5 gig free storage. Consider that your working folder, and then once uploaded to Dropbox you can send a emailed link to the publisher allowing that recipient the ability to "see" your file (and thus download it).

Why anyone would send files via DVD or other physical storage apparatus is beyond me.

Good luck!

I have scanned thousands of images for a railfan publisher. All the images I scan are at 4,000 dpi but scanned as 8 bit tifs not 16 bit that Chico uses. This gives an image size of around 55 megs vs 165 megs.

Sneebly

PS: The scanner I use is either a Nikon Coolscan 5000 or 5. The 5 is mine while the 5000 is the publishers.

The answer to the OP's original question is 3,600 ppi (300 ppi x 12-inches = 3,600 pixels wide).

Incidentally, resolution is correctly expressed as PIXELS per inch (ppi) rather than dots per inch (dpi).

I posted a resolution tutorial in this thread many moons ago. It might help you sort this stuff out.

http://www.trainorders.com/discussion/read.php?9,1315869

For the publication I work for, scans at least 4000 pixels in the long direction are desired, so your 300 x 12 = 3600 is a tad low and the 4800 is above the 4000 threshold. Follow what Chico or Sneebley post anded and you will be good. If you are going to physically transfer files do it with a flash drive but the modern way is either Dropbox or Google Drive.

RWJ

seaboardc30-7 Wrote:
-------------------------------------------------------
> When scanning slides and prints to burn onto a CD
> and send to national RR publications, what DPI
> should be used to make the scans? What should the
> dimensions of the scans be?
>
> From reading technical manuals regarding scanning
> slides and prints I am totally confused. When
> uploading images taken with a digital camera the
> preferred DPI is 300, and the preferred width is
> 12 inches. However some of the manuals suggest
> that the scans be 4,800 DPI for good
> reproduction.
>
> Why is there such a difference in DPIs?
>
> Many thanks in advance. Any tips for scanning
> would be welcome.
>
> Seaboard