Test Report SilverFast Multiexposure and Scanner Dynamic Range for Canon CanoScan 8600F
Image Engineering Dietmar Wueller, Augustinusstr. 9D, 50226 Frechen, Germany, Phone +49 (2234) 912141 Fax +49 (2234) 912142 www.image-engineering.de

20.04.2007

Introduction
In Version 6.5 of the scan software SilverFast by LaserSoft Imaging a feature called Multi Exposure was added to increase the dynamic range of scanners. For scanners that offer different exposure times multiple images are scanned with at least one image at each exposure time. These images are combined to a high dynamic range image. This study was made to evaluate the dynamic ranges achieved by using this technology and compare the result to a single scan. To determine the dynamic ranges the method described in ISO 21550 was used.

Evaluated Scanner

Canon CanoScan 8600F
The OECF and dynamic range achieved with a single scan.
The OECF and dynamic range achieved with a multi exposure scan.

Measured Dynamic ranges

If a scanner provides multiple exposure levels the Multi Exposure feature of SilverFast increases the dynamic range.
Multi Exposure Canon CanoScan 8600F

Values in densities

without 2,89 D

with 3,62 D

Frechen 20th of April 2007 Image Engineering Dietmar Wueller

From Piles to Files

Scanning Your Old 35 mm Negatives

My Workflow

Overview
Define your mission Organize the piles Buy a scanner Structure the files Choose workflow Enjoy the journey

Define Your Mission

Why are you doing this? Who is your audience? What do you want for output?

Defining Your Mission

What other media will you input?
Slides? Medium format film? Prints?
How much time will you dedicate?
Ex. 1/2 a roll per night is 300 rolls in 2+ years!
Are your computer power & storage sufficient?
Ex. 24 frames X 300 rolls X 6 MB/image = 43 GB

How much will you pay?

$200, $500, $1000, & up
Do you really want to do it yourself?
Colonial Photo charges $1.50 per strip for a 2000 x 3000 dpi scan 0.50/frame x 24 frames x 300 rolls = $3,600

Organizing the Piles

Find the negative sets Sort by date Assign an index ID #, (100, 101, 102)
Date: June, 1970 ID#: 123 Cape Cod 1970
Assign a name (optional) to each set Pick a post-scan storage method
The PrintFile loose leaf book solution

Buying a Scanner

Flatbed - More versatile
Canon 8600F ??? Canon 9950F (discontinued) Epson 4990 Epson V700 Epson V750M-Pro $180 $200 $500 $750
Dedicated Film - Maybe an edge on speed
Nikon Coolscan V ED Nikon Coolscan 5000 ED $550 $1000
Vincent Oliver on Photo-i.co.uk.com The Epson Perfection V700 is a marked improvement over previous models, optically it's producing scans that rival dedicated film scanners and in many cases surpass them.
Scanner Jargon - Resolution
How much optical resolution do I need?
35 mm negative: ~ 6 MP* or 2000 x 3000 dpi A 1200 dpi scan gives a 1080 x 1680 ppi image and will print a 4 x 6 (at 270 dpi) A 2400 dpi scan doubles these numbers Scanners can do 4000, 4800, and 6400 dpi
Diminishing returns for extra time and size * A simplified, low estimate, but reasonable for this discussion
The important resolution # is the first # in the resolution spec: e.g. 4800 x 9600 Ignore interpolation numbers
I.e., Epson V700 claims 12,800 x 12,800 dpi

Scanner Jargon - Dmax

What is Dmax and should I care?
Density is log(1/Transmission) Dmax varies with the media
1.7 2.0 2.8 3.4 (2%)* (1%)* (0.2%)* (0.04%)* Magazine Color print Color negative Color slide

Scanner Dmax

4.0 Epson 4990 & V700 4.2/4.8 Nikon V/5000
*% of incident light transmitted
Dmax claims: Hype or fact
Scantips.com says there is no standard, only hype ISO 21550:2004 Photography, Electronic scanners for photographic images, Dynamic range measurements Epson commissioned lab tests by NSTL using this standard

Dmax NSTL tests

Scanner Epson Perfection 4990 Photo Epson Perfection V700 Photo Canon CanoScan 4200F Canon CanoScan 8400F Canon CanoScan 9950F HP ScanJet 4370 HP ScanJet 4850 HP ScanJet 4890 MicroTek ScanMaker i900 Resolution 4800 6400/Dmax More than 4.0 More than 4.0 Less than 3.0 Less than 3.0 Less than 3.0 Less than 3.0 3.1 Less than 3.0 Less than 3.0
Scanner Features - ICE or FARE

What is digital ICE?

HW/SW to find dust and scratches and remove them Does not work on Kodachrome or silver-based B&W (dye-based is ok) Works much better than any SW-only method
FARE is Canons own system
It may be inferior to ICE

Scanner Features - ICE

Example of dust removal with ICE on V700
Original Enlarged Scanned with ICE

Scan time

How long does it take?
At 2400 dpi for my Epson 4870, Epson Product Bulletin shows:
ICE off Slide Negative 1 min 1.5 min ICE on 8 min 10 min
4990 and V700 are maybe 10% faster

Structuring the Files

One negative set (roll) per folder Folder name is the negative set ID#, same description and date Every folder matches a PrintFile loose-leaf page
File names: use scanner defaults & rename later Dont bother trying keep images in same sequence as negative frames. Establish a backup plan!

Workflow

Custom or production scan?
Custom: The piles last much longer
Pick photos Adjust levels, curves, white balance/color cast removal, cropping, etc. Higher quality - More data available during scan
Production: The piles diminish much faster
Scan everything Adjust later in Photoshop, Lightroom, etc. Lower quality - Less data available
Begin with the latest negatives and refine your techniques on them Older negatives have faded dyes and require more work

File size and format: Jpg or Tif?
To simplify discussion, round negative size up to 1 x 1.5 inch
Scan Resolution (dpi) Image dimensions (pixels) Megapixels in image Tif file size in MB (24-bit color)* Print size (inches) @ 300 dpi x 6 4x2400 X x 4000 x x 4800 x x 6400 x x 32
* Double the tif filesize for 48-bit color.
1. Clean scanner platen (if needed) 2. Set up PrintFile sleeve and hard drive folder 3. Select, clean and load negatives
Use cotton gloves, cleaning cloth and pressurized air
4. Make prescan 5. Select frames for adjustment

6. Adjust frames

Beware the impact of nostalgia!
7. Launch the scan at 1200 dpi if I can spare the computer for 90 minutes 8. Otherwise, reboot first thing in the morning & let scan run while I get ready for work. 9. Remove negatives and store in PrintFile sleeve

References

Reviews
Mandatory reading: www.photo-i.co.uk for Epson 4990, V700 & V750 and Silverfast Ai. (The V750 review compares also tackles the flatbed vs. film scanner by comparing it to a Nikon LS 9000 ED)

Information

www.scantips.com (Some info is old) www.hamrick.com (Vuescan software) www.lasersoft.com (Silverfast software)