Many slides to scan

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j4h

Can someone give me an answer as to what resolution 35mm slides should
be scanned at. Mostly for 4x6 prints. I have about 2000 slides to
scan. I have tried 300 ppi at 4x6 target size which gives 1200x1800
size pictures. This seems okay, but then I read some sites and numbers
like 1000, 2000, 4000 are recommended. I have a epson 2480 photo
scanner. Thank-you
 
Can someone give me an answer as to what resolution 35mm slides should
be scanned at. Mostly for 4x6 prints. I have about 2000 slides to
scan. I have tried 300 ppi at 4x6 target size which gives 1200x1800
size pictures. This seems okay, but then I read some sites and numbers
like 1000, 2000, 4000 are recommended. I have a epson 2480 photo
scanner. Thank-you
Click to expand...

for 4x6 prints, your scanning to a 1200x1800 pixel size is fine.
Higher pixel sizes are sometimes preferred if
a. there is any chance that larger prints will be required
b. you want to edit or crop the image before printing it to 4x6

I personally scan almost all of my 35mm at the maximum resolution of
my scanner, because I don't know beforehand if I'll want a large
print, and because I edit virtually every scan.
Charlie Hoffpauir
http://freepages.genealogy.rootsweb.com/~charlieh/
 
thanks for the answer. now I also noticed on some site that slides are
different than photos and have more detail, would that be a reason why
more than 300 ppi is actually required. thanks
 
thanks for the answer. now I also noticed on some site that slides are
different than photos and have more detail, would that be a reason why
more than 300 ppi is actually required. thanks
Click to expand...

sorry to be a pain, but the maximum I guess is 2400 ppi on my scanner.
would you scan 2400 at the original size (slide size) or the target
size.
thank-you
 
sorry to be a pain, but the maximum I guess is 2400 ppi on my scanner.
would you scan 2400 at the original size (slide size) or the target
size.
thank-you
Click to expand...

The 2400 ppi resolution refers to the maximum optical resolution of
the scanner. The scanner scans the original, so the 2400 refers to the
original. If you compare 2400 ppi scans of the same slide on your
scanner to 2400 ppi scans of the same slide, scanned with a real 35mm
film scanner, you'll find the scan from the film scanner looks
"sharper". This is because of several factors, including the fact that
the film scanner does a better job of detecting shadow details, and
the fact that scanner manufacturers are often pretty "free" with their
specifications. Pictures on a web site may seem to have more detail
when scanned from film than from pictures, but the real detail is
limited to your ability to view that detail on your monitor. What you
may be seeing is the improved dynamic range of the film scan vs the
photo scan.... or the fact that the photo may have been made from a
scan at lower resolution than optimum.
Charlie Hoffpauir
http://freepages.genealogy.rootsweb.com/~charlieh/
 
Charlie - Re: scanning slides on film scanner. I scan on my Minolta 5400 at
the max resolution of 5400ppi using Silverfast as scanning software. Image
then opens in Photoshop as a TIFF, but every little editing change is
incredibly slow at this resolution. Is there a workflow detail I'm missing
that would keep the resolution but speed up the editing in Photoshop?
 
Per (e-mail address removed):
Can someone give me an answer as to what resolution 35mm slides should
be scanned at. Mostly for 4x6 prints.
Click to expand...

I'd say it depends on your tolearance for file size.

Mine is about 2 megs.

To get that, I scan at 4,000 dpi and save at JPEG quality 80.

My rationale is that when I zoom on the scan via ThumbsPlus, I want the scan's
rez to fall apart at about the same time that the film's does. For me and the
quality of my particular size, 4,000 dpi does that pretty well.

The extra rez is also nice for cropping.
 
Per Len Schweitzer:
Is there a workflow detail I'm missing
that would keep the resolution but speed up the editing in Photoshop?
Click to expand...

I'm not Charlie, but how stringent are your quality requirments? The diff
between Photoshop's response handling TIFF and JPEG has always been huge for me.

Another thing is the PC itself. After starting a project at a client site for
which the client bought me a new Athalon-based bottom-of-the-line-but-current
PC, I realize that my home machine had become a dinosaur. Replaced it with a
box that I built up on a Asus board with a P4 chip and a gig of memory and photo
processing changed like night and day.
 
Charlie - Re: scanning slides on film scanner. I scan on my Minolta 5400 at
the max resolution of 5400ppi using Silverfast as scanning software. Image
then opens in Photoshop as a TIFF, but every little editing change is
incredibly slow at this resolution. Is there a workflow detail I'm missing
that would keep the resolution but speed up the editing in Photoshop?
Click to expand...

It may be that you have the bit depth set for 16 instead of 8 per each
color (RG), that will certainly increase the file size dramatically,
and slow down things, without a very big increase in quality. I have
also found that saving as a compressed tiff, although reducing file
size slightly, takes much longer to open the file for editing.... but
that wouldn't increase the time to do actual edits.

On the other hand, it may be just too large a file size for the memory
you have. I've read somewhere that PS needs 3x the size of the image
to do an effective edit.... if your image is 24bit then the file size
is about 100 MegaBytes. that's pretty large, so you need 300 MB of
memory dedicated to PS just to edit the image. Any extensive editing
will get into using the disk drive as a swap, which will certainly
slow things down a lot.

My scanner doesn't scan at that high a resolution, so I don't see a
similar problem, with 1 GB of total RAM. DO you have at least a GB of
RAM? Can you tell if the disk drive is being used during editing? Can
you verify the file size of the scan that you're editing?
Charlie Hoffpauir
http://freepages.genealogy.rootsweb.com/~charlieh/
 
Charlie - Re: scanning slides on film scanner. I scan on my Minolta 5400 at
the max resolution of 5400ppi using Silverfast as scanning software. Image
then opens in Photoshop as a TIFF, but every little editing change is
incredibly slow at this resolution. Is there a workflow detail I'm missing
that would keep the resolution but speed up the editing in Photoshop?
Click to expand...
One other point.... are you sure that you "need" to scan at 5400 ppi?
For a 35mm negative, that would let you print to 25" x 17" (using the
dimensions of a 35mm negative I have handy, and assuming printing at
300 ppi). Very few of my negatives are good enough to make a print
that large.... in fact, I'd have to say really none of them are. My
35mm images were all shot hand-held.... and even though I was pretty
good at holding a camera steady, there's enough camera movement to
make a 5400 ppi scan unnecessary.
Charlie Hoffpauir
http://freepages.genealogy.rootsweb.com/~charlieh/
 
Charlie - Re: scanning slides on film scanner. I scan on my Minolta 5400 at
the max resolution of 5400ppi using Silverfast as scanning software. Image
then opens in Photoshop as a TIFF, but every little editing change is
incredibly slow at this resolution. Is there a workflow detail I'm missing
that would keep the resolution but speed up the editing in Photoshop?
Click to expand...
Yep. You need a faster computer with more RAM.

--

Hecate - The Real One
(e-mail address removed)
Fashion: Buying things you don't need, with money
you don't have, to impress people you don't like...
 
Actually a Lasersoft tech support person said to scan at the max of 5400ppi
to capture every last scrap of info in the slide. My max print size will be
on 13x19 sheet...maybe image size of 10x16 or thereabouts. Some of my
images were handheld, some tripoded. I'm looking for a dpi setting that
retrieves as much as possible from the slide without having each edit step
in PS takes 2-3 minutes even with a gig of RAM.

Thanks for your input, Len
 
If the cropping is fine you can have Photoshop batch resize your images
for you from the 5400 dpi files.
 
Per Hecate:

"Intel givith. Microsoft taketh away."
Click to expand...

Not in this case. Are you a Photoshop user? :)

--

Hecate - The Real One
(e-mail address removed)
Fashion: Buying things you don't need, with money
you don't have, to impress people you don't like...
 
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