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Nine7Three
14-Mar-2018, 06:42
I recently purchased a 1866 Voigtlander f4 lens and trying to figure out the focus on it. To me it looks complete it has rear and front lens optics. I did the wall test and image came into focus around 11.5 in (measured from waterhouse slot to wall)
When i mounted the lens to my 8x10 Century Studio with 5x7 GG back image would only come into focus when rear standard was about 1-2in from front standard. (Very sharp image very shallow DOF) Pretty much smushed the bellows. subject about 3 ft away Why is this?

I would think by the wall tests this should be the same scenario with image on GG when bellows is stretched. Kinda thrown off by this. I tried backing up to about 8ft of subject and it was even more OOF.:confused:


Any ideas? Is this lens a paper weight? Lens optics reversed? Missing a lens?



Thanks,
Michael

mdarnton
14-Mar-2018, 06:57
It does not make any sense at all that it would focus at a different distance from the wall than the ground glass. Did you take it apart between these tests, and put something back together wrong? If not, one of these tests is wrong. Which one? Do both again.

Nine7Three
14-Mar-2018, 07:06
No i never re-arranged rear or front lens only unscrewed rear to get a look inside. I am still very confused....I did the Wall test this AM bc I wanted to make sure a image was coming into focus at a reasonable distance. I used my window to project onto wall it was 10-15 ft away. Did i do test correct?


It does not make any sense at all that it would focus at a different distance from the wall than the ground glass. Did you take it apart between these tests, and put something back together wrong? If not, one of these tests is wrong. Which one? Do both again.

Pere Casals
14-Mar-2018, 07:47
Your wall test is correct, if you replace the wall with a GG, as Michael said, it should project just the same. I'd do again the wall test to be sure that it's working like before unscrewing the rear, then measure the flange to the wall distance, and use same distance for the flande to GG.

When doing the wall test do not focus the window itself, but subjects that at very long distance and that are seen thought the window, be careful if you use sun, it's a bright reference but you can burn something, even one eye...

Nine7Three
14-Mar-2018, 08:04
Thanks Yes, ill have to do more testing i was just initially confused bc I own a 14in Wollensak and for portraits... lens aprox 5ft away from subject and GG from front standard is aprox 12-14in for sharp focus.



Your wall test is correct, if you replace the wall with a GG, as Michael said, it should project just the same. I'd do again the wall test to be sure that it's working like before unscrewing the rear, then measure the flange to the wall distance, and use same distance for the flande to GG.

When doing the wall test do not focus the window itself, but subjects that at very long distance and that are seen thought the window, be careful if you use sun, it's a bright reference but you can burn something, even one eye...

Steven Tribe
14-Mar-2018, 09:07
If there was a missing rear lens, it would have a much longer focal length!

The focal length may be shorter than you image, especialy if it is nearer F3 than F4. If the lens diameter is around 3", then the focal length for the lens should be about 9 1/6".

Nine7Three
14-Mar-2018, 09:25
Yeah,it deff has a rear lens and in place! It was marked f4 prob by photo studio not factory... Added 2 images of lens. Rear element is about 3 1/2
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If there was a missing rear lens, it would have a much longer focal length!

The focal length may be shorter than you image, especialy if it is nearer F3 than F4. If the lens diameter is around 3", then the focal length for the lens should be about 9 1/6".

Steven Tribe
14-Mar-2018, 09:46
But the glass is 3", which is what Voigtlander measures for the adverts/catalogues.
There was an earlier series which was nearer F4 - glass diameter (front lens) 81mm focal length 11".

Nine7Three
14-Mar-2018, 09:59
Thanks for the info! yes from my window/wall test thats what i measured about 11' from waterhouse slot to wall. Just waiting for the 5:00 whistle to give it another test on the GG. Just bizarre that when I had the GG pulled back stretched about 8-12in its was just OOF (subject 6ft way) and i was moving my camera further way and just got worse from there. :confused:



But the glass is 3", which is what Voigtlander measures for the adverts/catalogues.
There was an earlier series which was nearer F4 - glass diameter (front lens) 81mm focal length 11".

Nine7Three
15-Mar-2018, 07:17
Did more testing... so it looks like it is indeed 11in and giving me a sharp image on GG Just not use to being super close to subject (3 1/2 away) standards are stretched 11in from Waterhouse stops to GG. Compared with my Wollensak Vesta it seems like a lot wider of lens not sure of the mm but no where close to 300-200mm. Would this make it a not a Portrait lens?


Thanks
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Pere Casals
15-Mar-2018, 07:46
You have an amazing protrait lens, single question is if (for you) it will work better for head&shoulders or for half body, also it will work very different for 45, 57 or 810. Just imagine you are a 1866 photographer and you have to earn money with this glass, you only have this one. Fantastic protraits will come...

Nine7Three
15-Mar-2018, 07:52
Awesome thanks Pere!!! I will be testing it out this weekend I'm thinking Head Shoulder super tight shot....I will shoot 5x7 first then move up to 8x10 Happy to have acquired this lens since my fastest acting lens is an f5. The f4 should cut my exposure time to 6-8 sec


You have an amazing protrait lens, single question is if (for you) it will work better for head&shoulders or for half body, also it will work very different for 45, 57 or 810. Just imagine you are a 1866 photographer and you have to earn money with this glass, you only have this one. Fantastic protraits will come...