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Jack the boatman
22-Jul-2011, 07:42
Hello,
I am planning to run an experiment to find the optimum film speed for my equipment and developer.
The film will be Adox ISO 50, developed in Neofin Blue made up from the raw chemicals and scanned using a Canoscan 8800F (This scanner only scans up to 6cm width) I will therefore select the same portion of each negative. I will run a series of negatives taken of a grey card and perhaps a focussing chart at various speeds from 2 stops below nominal up to 2 stops above nominal.
I plan to assess the outcomes firstly by inspection of the negatives and then by the results of the scans i.e. visual appearance and histograms.

I will use Nikon NX2 software and/or Adobe elements 9.

My question is: Although I can standardise all of the manual operations I make, will this be undone by the scanner trying to optimise each result, even if I have put everything to manual? Ansell Adam's zone system is brilliantly simple, but he used densitometers to measure the negative, what is the best way to update his system for a semi digital process?

Thanks

Jack

Ken Lee
22-Jul-2011, 09:06
You might find these articles interesting:

Testing Black & White Film (http://www.kenleegallery.com/html/tech/testing.php)

Scanning Tips (http://www.kenleegallery.com/html/tech/scanning.php)

erie patsellis
22-Jul-2011, 11:16
Hello,
.... Ansell Adam's zone system is brilliantly simple, but he used densitometers to measure the negative, what is the best way to update his system for a semi digital process?

Thanks

Jack

Two separate issues, one is maximizing your film capture, the other is maximizing your scanning technique. Calibrate the film's response first, then optimize your scanning techniques.

I, for one, still use densitometers to assess exposure and development. While some scanner programs (such as VueScan) purport to have the ability to read density, it's far easier for me to use one standardized and calibrated instrument across all my work (I also work as a lab manager for a local studio part time). The whole idea behind the Zone System is to optimize your negative for printing on "your" standard grade paper, adjusting exposure and development to achieve a target Zone I density and Contrast Index, based on your printing methodology.

For scanning purposes I find a lower Contrast Index (~.85 to .9) works best, a subtle change from printing. For images that may go either way, I have a Zone VIII target of 1.15 over Fb+fog.

One of the biggest advantages of the newer films is greatly increased dynamic range, ideal for scanning if you calibrate for an extended tonal range as well (aiming for a total CI of ~1-1.25) scanning is simple and easily done, even on "less capable" scanners.

Ken Lee
22-Jul-2011, 11:18
I just updated the article (http://www.kenleegallery.com/html/tech/scanning.php) on Scanning, to cover VueScan software.

SW Rick
22-Jul-2011, 11:45
I just updated the article (http://www.kenleegallery.com/html/tech/scanning.php) on Scanning, to cover VueScan software.

Thanks, Ken!

Rick

Jack the boatman
25-Jul-2011, 06:27
Ken, Erie,

Thanks for the tips.

Jack