step wedge - contact or enlarge?

PVia

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Oct 3, 2006

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Pasadena, CA

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• Mar 20, 2008

• #1

Hi all...

Just needed to ask this question re contact printing a step wedge (or anything else for that matter)...

If I set my enlarger to a specific height & set the lens to a specific aperture, will I get the same printing density on my paper, whether I contact print or enlarge a negative?

In other words, it's the same, right?

 

KenM

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Apr 22, 2003

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Calgary, Alb

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• Mar 20, 2008

• #2

If you're testing, expose it the same way you do your prints. Note that a contact print will have the highest contrast, and as you increase the size of the enlargement, you'll need to increase the contrast to maintain the same level of local contrast. Or at least the same level of *apparent* local contrast.

For a step wedge, you'll be awfully close regardless of the technique used.

 

KenM

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Apr 22, 2003

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Calgary, Alb

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• Mar 20, 2008

• #3

What I meant, was that a step wedge has very little local contrast - it has large areas of the same local contrast, and changing the enlargement level won't affect that, assuming that you change the exposure to compensate for the great enlargement.

 

dancqu

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Willamette V

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• Mar 20, 2008

• #4

PVia said:

If I set my enlarger to a specific height & set
the lens to a specific aperture, will I get the same
printing density on my paper, whether I contact
print or enlarge a negative?
In other words, it's the same, right?

Click to expand...

Correct. In either case the light passes
through the step wedge and coverage
remains the same.

I project a 6x6 onto 5x7 when testing paper.
I've calibrated an Ilford EM-10 against the
wedge for use as a densitometer. Dan