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View Full Version : velostigmatic11, vitax, and other lenses that defocus



jnantz
4-Dec-2016, 18:15
i can't list all the lenses tha have this device to soften the image
they don't all do the same thing ...

i used to have a vitax and remember the know moved the rear element
i know some users re-focused for whatever reasons they had, after they turned the knob
i used it when i was stopped down beyond 4ish so i would still have the soft effect and not much DOF.

i know some folks modify their velo so it softens even more than designed, folks unscrew the front element of their favorite lens 1/4 turn
or remove the front element ( almost ) from their teleoptar ...

whatever it is that you might do, do you focus, defocus and refocus? do you focus, stop down a little and defocus paying attention to the ground glass,
do you shoot wide open and defocus again?

i got in the habit of focusing on something either infront of or behind my subject, if it wasn't a portrait ( or sometimes i do ) and gave up on the defocus knobs and unscrewing the lens &c

what is it that you do, and what sort of effect ( good or bad ) does it give? and what DON'T you do ?

Mark Sawyer
4-Dec-2016, 19:35
...do you focus, defocus and refocus? do you focus, stop down a little and defocus paying attention to the ground glass, do you shoot wide open and defocus again?


Same simple rule as with every other soft focus lens, adjustable or not: focus at the taking aperture with the lens in the configuration you'll use it at.

This is even more true with the adjustable lenses, though, as they change focal length slightly as you shift the element spacing, and that just throws things out of focus.

Ari
4-Dec-2016, 20:42
Couldn't have said it better than Mark did.
I have the Velostigmat with the modified ring that goes past "5", and the only caveat is that if you've set diffusion high enough, it won't be easy to tell if you're in focus or not.

jnantz
5-Dec-2016, 03:28
thanks !
i had never heard or read that.
i have instructions for a veritar
and it says to stop down a little and
then focus. i took that as the instructions
for all the other lenses i ended up buying after that ..

Simon Benton
5-Dec-2016, 06:47
I use an Imagon and a Verito on a 4 X 5 Super D and put on the appropriate Imagon disc/set Verito aperture required and then compose and focus.

goamules
5-Dec-2016, 14:46
There is the "advanced technique" of focusing, such as described in the catalog for the Kodak 305 and 405 portrait lenses. But it really makes it harder than it should be, trying to account for the aberrations being different in front of, versus behind, the plane of sharpest focus. Look on the Camera Eccentric site catalogs to see it.

Maris Rusis
5-Dec-2016, 16:42
Another approach for the soft + hard image effect is to double exposure. The first exposure is with the lens stopped down for sharpness. The second is wide open for the "glow". Balancing the two exposures delivers a variety of effects. Experiment may be rewarding.

jnantz
5-Dec-2016, 17:35
hi maris

i do that sometimes with paper negatives and retina prints
it gives a nice effect!