PDA

View Full Version : 120mm lens comparison



Colwyn Griffith
4-Mar-1999, 08:21
I`m looking for a 4x5lens that can give me the most depth of field in "Makro" si tuations. At the same time I need a great shapness quality so I can make large p rints (55x55inches). For example these "Makro" situations have the following dim entions: 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 i sn`t too confusing.

Alan Gibson
4-Mar-1999, 09:20
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.