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Scan speed-B/W 35mm negatives

PostPosted: Sat Sep 21, 2002 6:51 pm
by fredila
I am new to scanning 35mm negs. Am using SE6 with the Epson 2450. My computer is USB2 enabled (as is the scanner) and runs at 1.8ghz.

In scanning a 35mm b/w negative that is about .9 x 1.4 inches (slightly cropped) to 5.0 x 7.8 inches at 300dpi, I produce a 3.33mb file. It takes about 4 and 1/2 minutes (270 seconds) to complete the scan.

I am scanning in 16->8bit grayscale.

Is this scanning time about right?
Any other tips that would alter what I am doing?

Thanks in advance.

Fred :D

Transparency Scan Time of Epson Perfection 2450

PostPosted: Sat Sep 21, 2002 10:38 pm
by President_LSI
Transparency Scan Time of Epson Perfection 2450

The scan time of an Epson Perfection scanner 2450 is a compromise because of its design. The reason is the low light transparency adapter. Since the light from the transparency adapter is not high enough, the exposure time (the time length how long the CCD is exposed to light) has to be substantially longer than with reflective scanning.
That is the reason for the slow scanning speed regardless whether you scan colour or grayscale. USB1 or USB2 are both faster than the data is generated with transparency.
The much faster scanners with transparency are the more sophisticated Expression 1680 or dedicated film scanners.

Thanks for the response

PostPosted: Sun Sep 22, 2002 12:52 am
by fredila
Thank you for the prompt and understandable response.

I considered a dedicated film scanner...but frankly, I only have about 100 old b/w negatives to archive to CD. I have been into digital photography for a few years and seldom have the need for a negative scanner.

I will say that your Silverfast software produces a much better (finer detail, better highlights, etc.) scan of my negatives (Using the Ilford setting) than the Epson Twain 5 does.

I do find that the Epson Twain takes about 1/2 the scan time of Silverfast to produce the same size file....not sure why??? :roll:

Thank you again for the explanation.

Fred

Wow! I can't believe the difference in scan time

PostPosted: Thu Sep 26, 2002 3:48 am
by fredila
Just got around to doing my first reflective scan. I scanned an 8x10 at 300dpi. It took about 20 seconds and produced a 20mb file.

That's about 10 times faster than it took to produce a 3mb file of a 35mm negative.

Does that sound right? :-?

Thanks again,

Fred

Reflective 10 times faster than transparency

PostPosted: Thu Sep 26, 2002 9:01 pm
by President_LSI
That is right! The relation is about ten times slower for transparency!

Same with Epson 3200?

PostPosted: Mon Mar 10, 2003 4:01 pm
by Videonisse
I have done similar "scan time" test on my new Epson Perfection 3200 Photo. What I found out is that it's no difference in scan time whether I use reflective or transparancy negative/positive settings, is this a correct behavior with this scanner?

I would expect a longer exposure time (=scan time) for at least the negative scans.

I used SilverFast Ai v6.0.1r38 on a 2GHz Celeron PC with Win XP and Firewire. In all cases I used a frame of 24x36mm and 3200dpi 48->24 bit. For the color negative scan I used Kodak Gold 100 in Negafix. All other settings was default/auto.

/Mischel

Scan time with Epson Perfection 3200

PostPosted: Tue Mar 11, 2003 7:51 pm
by President_LSI
Scan time with Epson Perfection 3200

The scan time for transparency for positve or negative will be the same. For reflective it should be substantially faster. Of course it would be senseless to scan a reflective at 3200 dpi, since you would only enlarge the reflective minimal maybe up to 400%, that would be a scan resolution of about 900 dpi.
Remember, in SilverFast you do not set the absolute scan resolution. Instead you set a Line Screen, such as 152 lpi, a quality factor = 1.5 and the desired final image size and SilverFast would calculate the optimum scan resolution for you!

Check out the scanning concepts: https://www.silverfast.com/show/scanningconcept/en.html

PostPosted: Tue Mar 11, 2003 8:51 pm
by Videonisse
Thanks for the quick respons!

When testing Epson Scan, v**s**n and SilverFast I found out that your software is the only one who not add extra "CCD exposure time" when scanning color negative film. This is a benefit for you in total scanning time per frame but my question is: -for SilverFast Ai, is this is a bug or a correct behavior for Epson 3200?

Reason wy I ask this is that I currently evaluate scanner softwares that will best fit my purposes to digitize my archive of color negatives.

This means I will batch scan a very large amount of film and archive in a standard resolution. Due to file sizes etc I plan to batch scan with 3200dpi and then down-sample to about 2400dpi (maybe less) and save as a jpg with very high quality compression. It should enable me to print those (200-300dpi) photos in A4-format with good quality on a inc-jet printer and still have some space for further cropping if needed. I assume this is very different from normal pre-press standard so I'm not sure how I will benefit from using line screen and quality factor to decide my scan resolution? However, that's not the important question right now.

I'm new to scanning and have not yet been able to compare scans for high quality negatives but if Epson 3200 needs the extra CCD exposure time for color negatives I will most likely find out in my planned tests that SilverFast Ai does not deliver highest possible quality for color negatives on this particular scanner.

A clear statement from LaserSoft on this question would really help me and probably many others as I can imagine that many new Epson 3200 owners has same needs as my self and will therefore need the batch scanning functionality as in for example SilverFast Ai.

Thanks,

Mischel

PostPosted: Wed Mar 12, 2003 9:02 am
by LSI_Muenier
With (some!) Epson scanners, the exposure cannot be adjusted directly, but is controlled indirectly (technically speaking by the gradation curve). I will do some testing and give you a more distinct answer later on.