View Full Version : Velostigmat is mounted, and ready for a test drive !

Steve H
1-Nov-2006, 07:42
I got the chance to finally mount the 12" Velostigmat II that I purchased recently. I cut the lensboard (sinar) on a CNC machine to be sure I had it just 'right', and then drilled/tapped it for the flange. Im planning on leaving work early today (as it looks to be one of the few Michigan days w/o rain...) and give it a shot.
I know that this was recommended to be used on an 8x10; however Im going to be using it on my 4x5. Dependant upon the adjustment ring, does this lens give a uniform softness, or does it slowly bleed away from the center ? I know testing needs to be done, but curiosity is killing me :D
In other words, will I still get the same 'effect' on a 4x5 that I would with an 8x10 ?

Thanks !

1-Nov-2006, 15:42
If this extrapolation helps any: a 9-1/2 Velostigmat (non-variable, unfortunately) is perfectly usable on 2-1/4 format, quite soft up to about f/8. On 4x5, it becomes "relatively" sharp at f/6.3 (versus f/4.5 wide open) because of the smaller enlargement factor.

The softness does increase towards the edge of the field, but seemingly not as much as some other designs (Verito, etc.). This is probably an advantage, since the depth of field is so shallow at the larger apertures.

The old, uncoated Velostigmat seems to have considerably less light transmission than more modern lenses, so be conservative if you are using a film/developer combination with poor shadow speed, particularly for the first few experiments.

Good luck!

Michael Graves
1-Nov-2006, 15:45
I used to have a 12" 4.5-64 Velostigmat. Still kicking myself for selling it. I was a moron.

No, wait...that's not right. I still AM a moron.

But it was somewhat soft up until about f11, and by the time you were at f45 it was tack sharp. At f64 it lost its charm. At 6, I lost my charm.

Ernest Purdum
1-Nov-2006, 16:43
I envy you the CNC. I used to have a shop with capabilities for doing all sorts of interesting things, but no time to do them. Now I have the time, but no longer the shop.

Your Velostigmat II, in contrast to the Verito and similar lenses, is basically a very ordinary anastigmat lens but in the version you have, a means of changing the spacing is provided. This throws off the correction for spherical aberration. While it is normal in lenses for the center to be sharper than the margins, particularly the extreme margins, the less corrected slpherical aberration would affect the entire image.

Your lens is quite appropriate to be used on 4X5 any time you want a longer view.

Steve H
1-Nov-2006, 18:16
Thanks again Gentlemen. I'll try to get a shot or two of my machine work; although I think it will be more impressive to see everything once the meniscus lens barrel has been milled.
On a different note - does anyone know where I can source a cable release for the thing ? It has external threads !

Thanks again,

4-Nov-2006, 11:16
On a different note - does anyone know where I can source a cable release for the thing ? It has external threads !

It should also have internal threads. Check again and see if a standard cable release won't fit. There were cable releases available which fit the external threads, but good luck finding one.