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lungovw
18-Dec-2008, 15:27
Hi Everybody,

I just bought a Graflex Optar 90 mm W.A. f/6,8 nš742105N.

What is the contruction type of this lens?


Large format greetings from Sao Paulo,



Wagner

Dan Fromm
18-Dec-2008, 15:35
4/4 double Gauss.

Don Dudenbostel
19-Dec-2008, 14:21
I'm not up on lens design but what other wides share this design. I have both the 90 and 108 WA Wallensak and assume both share the 4/4 design. Is the WA Dagor similar? Angulon? Seems like Nikon used a similar design for their 24mm RF lens but not certain. Not a wide lens but I believe my 203 7.7 Ektar is a 4/4 design as is the RD Artar.

Dan Fromm
19-Dec-2008, 16:12
Don, 4/4 double Gauss types have elements like this: (( (( | )) )), where | is the diaphragm. WF Ektars, the Cooke Ser. VIIb, Meyer Aristostigmat, some Leitmeyr Weitwinkels (Ole Tjugen has one that isn't), f/6.8 Dallmeyer and Ross WAs, ... are of the same type. Understand that all of these differ in the surfaces' curvatures, elements' thicknesses and spacing, and glasses used.

Y'r 203/7.7 Ektar (and my 203/7.7 Kodak Anastigmat) and Artars, Aviars, Celors and Dogmars are all () )( | )( (). There are some 4/4 lenses that are () )( | |) (|, where |) is plano-convex.

The WA Dagor and Angulon are 6/2 lenses. I'd bet that y'r 108 Wolly WA is more complex than any of these.

As far as I can tell, design type needn't have a lot to do with much that's important. For example, the 65/6.8 and 90/6.8 Wolly WAs are 4/4 double Gauss with the same coverage and maximum aperture as the equivalent Angulons and both types shoot equally well. Or, some say, equally badly.

lungovw
19-Dec-2008, 16:45
Thanks for the information. I have and tried already two other 4/4 double Gauss. One is a Wollensak Velostigmat Wide Angle Ser III f 9.5 8x10 6 1/4" Focus. It works very well in 18 x24 cm with enough lens quality for me. The other one is very old stuff: an Omnar from Emil Busch F:4,5 F=25,5 cm. As I use them in very old wood cameras I can't tell what is unshapness and what is camera shake or film x gg positioning.

With this Optar I intend to do snapshots in new years' eve party using some flash bulbs in a 7" reflector in a 4x5 Pacemaker. There might be some vignetting but that may also contribute to the atmosphere.

Thanks again and best wishes,

Wagner Lungov

Dan Fromm
19-Dec-2008, 18:21
Wagner, look here http://www.cameraeccentric.com/html/info/wollensak_14.html for some Wolly cross-sections. I don't think your f/9.5 is a 4/4, the cross section shows it as an 8/4. To check yours, count reflections from one cell. If 4/4, there will be four strong reflections and no weak ones, if 8/4, four strong and two weak. The weak reflections may be hard to see.

Cheers and Happy New Year,

Dan

Don Dudenbostel
20-Dec-2008, 07:06
Thanks for the information.

Mark Sampson
20-Dec-2008, 15:56
Don't forget that most Graflex Optars are OEM'd Wollensaks. They tell me that late Optars were made by Rodenstock, but I don't think I've seen one of those.

walter23
20-Dec-2008, 16:03
I just got a 90mm f/6.8 raptar (same as the optar). From what I've done so far with it I'd say it'll be perfect suitable for your application. Sharp enough for me and covers just fine.

Grant Evans
26-Dec-2008, 15:29
I just got a 90mm f/6.8 raptar (same as the optar). From what I've done so far with it I'd say it'll be perfect suitable for your application. Sharp enough for me and covers just fine.

I saw a really clean copy of this lens (90mm f6.8 Raptar that is) online for under $200. Does this lens have enough coverage for 5x7 as well? Have you done both color and B&W with it? Would appreciate any feedback you have about the quality of this lens.
Thanks for your time.

Brian Stein
26-Dec-2008, 19:27
My 6.8 WA raptar is sharp, covers 4x5, but will not cover 5x7. Only ever used it for B&W.

walter23
26-Dec-2008, 20:18
Wouldn't be suitable for 5x7.

It's not incredibly sharp if you scrutinize the negatives with high resolution scans (though I've really only got a couple of samples with it so far, some of which were handheld (so I can ignore those) and the others shot at night where focusing is a bit difficult), but it covers 4x5 fine and will make sharp enough prints for me. I haven't tried any movement with it (because it's on a speed graphic that doesn't really have much anyway, especially at 90mm where the standard is still inside the camera body), but I'm not optimistic because if you look through the cut corners the aperture is occluded by the lens barrel when it's wide open... in other words I think you have to stop down a bit just to get an image without vignette on 4x5.

I can provide 1200 DPI scan details later if you're interested. I really wouldn't expect it to cover 5x7 though.

I paid $50 for mine and it's in basically perfect shape (coated too, as indicated by the circled W or Cw symbol).

lungovw
29-Dec-2008, 17:06
Hello,


I mounted the Optar 90 mm in my Crown Graphic 4x5 and shot (handheld) the attached picture during our Christmas dinner.
I used Tri-X 320 ASA, the one that was already in the holder, otherwise I would use ASA 100 in this case, because there was a GE #5 flash bulb in a 7 inches polished reflector. Speed was 1/50 at f32. Film was developed 8 min at 23C in 510 Pyro.

Well, it looks like one of those Graflex + Flash Bulb snapshots. I am not pretending this was a lens test, it is just curiosity since we are talking about the lens. At f32 anything would do I guess.

Another point, on Dan Froom's comment about 4/4 or 8/4: I counted the reflections in the front cell of my Wollensak Velostigmat Wide Angle Ser III f 9.5 8x10 6 1/4" Focus, and I could not see the 2 faint ones. Only 4 strong and the ones that appear closer are smaller than the ones in the back and very much aligned (different from the Optar). If I remember correctly I think I saw in the Vademecum this lens classified as a double gauss. Now my Vademecum is stored in a HD that is not connected so I can't check. Could be that there was 4/4 and 8/4 under the same brand name?


Cheers


Wagner

Steve Hamley
29-Dec-2008, 18:26
Nice shot!

Cheers,

Steve