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Wollensak Velostigmat s.II 7_1/4In f4.5
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PostPosted: Thu Jul 20, 2017 10:46 am    Post subject: Wollensak Velostigmat s.II 7_1/4In f4.5 Reply with quote

Many thanks from Russia to France for the American Velostigmat.


This picture was taken by the И-50y lens (Индустар-50у).

the first tests of the Velostigmat lens on f4.5:











PostPosted: Thu Jul 20, 2017 5:11 pm    Post subject: Reply with quote

I suppose you know that the main attraction for those Velostigmats is the fact they can be turned into soft focus lenses by un-screwing the front element. This is the case with the longer FLs ones but I don't know if it applies to the shorter FL as well.
Have you tried that with yours?


PostPosted: Thu Jul 20, 2017 5:24 pm    Post subject: Reply with quote

dan_ wrote:
...the main attraction for those Velostigmats is the fact they can be turned into soft focus lenses by un-screwing the front element...


It was too difficult for me. I returned the lens to its original state. These are two pictures with a "soft" lens





PostPosted: Thu Jul 20, 2017 5:39 pm    Post subject: Reply with quote

Well, you get a different render of the background but not quite a soft focus effect. Probably the soft focus transformation applies only to longer FLs.
I like more the way it renders in the initial state, too.
I have a longer FL Velostigmat and it clearly shows a soft focus effect when un-screwing the front element.


PostPosted: Thu Jul 20, 2017 6:29 pm    Post subject: Reply with quote

I like the intact lens better.


PostPosted: Thu Jul 20, 2017 7:04 pm    Post subject: Reply with quote

For comparison, here are some quick tests of the way my Velostigmat (~7 inches) is progressively achieving the soft focus state while un-screwing the front element:

- progresive un-screwing the front lens




- and the effect pondered (to my taste)


PostPosted: Thu Jul 20, 2017 7:08 pm    Post subject: Reply with quote

dan_ wrote:
For comparison, here are some quick tests of the way my Velostigmat (~7 inches) is progressively achieving the soft focus state while un-screwing the front element:



Like 1 Like 1 Like 1

Now maybe I'll try again after your photos.


PostPosted: Fri Jul 21, 2017 6:01 am    Post subject: Reply with quote

Yes, wonderful SF lens it gets! I have one here too, .... somewhere


PostPosted: Fri Jul 21, 2017 7:37 am    Post subject: Reply with quote

That 'feature' of the Velostigmat is something you can do with any tessar or triplet. It is the spacing of the front two elements that controls the correction of spherical aberration. Increase the spacing and you get more SA which is what causes the soft, diffuse glow. Expensive 'soft focus' lenses that have a ring to dial in different levels of softness are doing the same thing - varying the spacing of two elements to increase or decrease SA.


PostPosted: Fri Jul 21, 2017 10:39 am    Post subject: Reply with quote

iangreenhalgh1 wrote:
That 'feature' of the Velostigmat is something you can do with any tessar or triplet.


That's the theory, Ian. In practice I've tried it with many Tessars, Tessar-type lenses and triplets in the 75-150mm range and only few of them really have the "feature". The best in this regard, from my tests, was the 105mm Radionar (triplet, more subtile transitions) and this ~7 inches Velostigmat comes in the second place. The strange fact is that the 80mm Radionar doesn't have the "feature".


PostPosted: Fri Jul 21, 2017 3:16 pm    Post subject: Reply with quote

dan_ wrote:
iangreenhalgh1 wrote:
That 'feature' of the Velostigmat is something you can do with any tessar or triplet.


That's the theory, Ian. In practice I've tried it with many Tessars, Tessar-type lenses and triplets in the 75-150mm range and only few of them really have the "feature". The best in this regard, from my tests, was the 105mm Radionar (triplet, more subtile transitions) and this ~7 inches Velostigmat comes in the second place. The strange fact is that the 80mm Radionar doesn't have the "feature".


Also tried quite a few lenses w/o success.... the usual difference between talking and DOING Wink


PostPosted: Fri Jul 21, 2017 5:50 pm    Post subject: Reply with quote

Of course I've tried it, with quite a few lenses, most large British ones by Cooke, Ross and Wray, looking for a good portrait lens for my Speed Graphic.

So arrogant, obnoxious Klaus is wrong yet again and showed us the difference between KNOWING and ASSUMING.


PostPosted: Sat Jul 22, 2017 9:27 am    Post subject: Re: Wollensak Velostigmat s.II 7_1/4In f4.5 Reply with quote

sergtum wrote:
Many thanks from Russia to France for the American Velostigmat.






Superb. I don't often see portraits of animals, but maybe I inhabit the wrong places. I see them more often caught fully in focus.

So you move the front element on its threads, rather than take it fully off for those soft focus pictures?

EDIT: I see dan explains it. Thanks. Vario soft focus!


PostPosted: Sat Dec 18, 2021 10:21 pm    Post subject: Reply with quote

I know this thread is old but I'm playing with Velostigmat II's now and it needs to be made clear that it is the front glass that you move forward not the entire front group. So you have to wedge something between the 2 pieces of glass so the front piece doesn't flop at an angle. I used solder wire like Jim Galli did, and if not think enough, use 2 strand twisted together. [https://flickr.com/photos/130387645@N03/51725418909/in/dateposted/]