120mm lens comparison

greenspun.com : LUSENET : Large format photography : One Thread

I`m looking for a 4x5lens that can give me the most depth of field in "Makro" situations. At the same time I need a great shapness quality so I can make large prints (55x55inches). For example these "Makro" situations have the following dimentions: 35-55cm wide by 30-50cm deep. The depth range that I`ve just mentionned is the minimum D.O.F needed. The height might vary from 15 to 40cm. Hope this isn`t too confusing.

-- Colwyn Griffith (colwyngriff@hotmail.com), March 04, 1999

Answers

You have relaxed your conditions since your last question on this topic. You appear to want a magnification range of 0.1 to 0.3. Plugging the numbers into the standard formulae: with c=0.1mm, aperture f/45, f=120, m=0.1 gives a DoF of 150cm. But m=0.3 gives a DoF of only 23cm.

This is independent of manufacturer, of course. And for your print size, you might not be satisfied with c=0.1mm (in other words, you might want a sharper print).

Have a nice day.

-- Alan Gibson (Alan.Gibson@technologist.com), March 04, 1999.


Moderation questions? read the FAQ