Re: Simple & Stupid Curve Generator for Digital Negatives

From: jack reisland ^lt;[email protected]>
Date: 05/28/04-02:59:45 AM Z
Message-id: <>

Sounds quite handy, but what about those of us without Exel? Is there any
other way of accessing the file?

Jack Reisland

Loris Medici wrote:

> Hi Don,
> I) Determine your exposure time for black (using a blank negative and
> bracketing, just like silver-gelatine printing).
> II) Expose your paper with a digital 100 step tablet using the time you
> found in step I (I made the 100 step tablet in Photoshop; 10x10 squares,
> starting with 1% luminosity - ending with 100% luminosity, each square
> 2x2cm @ 360dpi - you may use a less accurate scale if you like)
> III) Inspect the print and determine the first clear square - this will
> be your 100% density value. Use the eye dropper on the 100 step tablet
> file to determine the 100% density value equivalent in the 256 scale.
> IV) Use the value you found in step III as "Max Value" in the following
> Excel file:
> negatives.xls and create a curve using values in A column as input, and
> values in D column as output.
> V) This will give you a good starting point (assuming you're printing
> black-only or quadtone and your B&W output is pretty linear), print a
> photo which also includes 21-step wedge, evaluate & fiddle a couple of
> times.
> Hope this helps - I made my cyanotype curve using this method; it works
> for me.
> Regards,
> Loris.
Received on Fri May 28 03:00:13 2004

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