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View Full Version : Info on GRAY's Extreme Angle Periscope lenses wanted



Greg
24-Sep-2018, 16:50
I have and use a 5.9 No. 5 Gray Extreme Wide Angle Periscope on my 11x14. Bought the barrel optic and had it put into a Copal shutter by S K Grimes (no easy lens adaptation to a shutter for sure). The one piece of literature that I found about these lenses is that their f/10 largest aperture was for focusing only. When stopped down they covered 115 degrees. I have found both these to be true. My No. 5 lens is listed as covering 11x14, which it does. It actually illuminates a larger circle, but the image degrades past the 453mm circle of coverage for the 11x14 format. Actually there is some image distortion in the corners of the 11x14, but I have found it to be acceptable considering the age of the lens. Putting the aside the Hypergon, are there any optics out there that exceeded the Gray's 115 degree coverage? I often think of why this optic wasn't improved upon and marketed in the years after it was made. Having a 115 degree coverage, the designers of this optic were very talented in their lens design.

Dan Fromm
24-Sep-2018, 17:28
Greg, among modern lenses Rodenstock claims 120 degrees for the 35/4.5 Apo Grandagon (not a large format lens) and Schneider claims the same for their 38/4.5 and 47/5/6 SA XLs (again, not LF).

Among old lenses, Berthiot's 1912 catalog claims 115 degrees for the f/14 Perigraphe, offered in focal lengths from 45 to 800 mm. Later catalogs claimed smaller coverages.

We can only speculate about why so few ultra-wide angle lenses were offered. I've read that Hypergons were difficult to make. Perhaps few photographers could use such lenses effectively, therefore few were willing to pay for them.

Oren Grad
24-Sep-2018, 18:12
Dan, as you know, the 47 SA XL covers 4x5 so is LF even by our persnickety criteria. Also, Schneider claims 115 degrees for the 72 SA XL.

Particularly as standards for optical performance increased over time, I suspect that manufacturers simply concluded, correctly, that the demand for big-format ultrawides at the size, weight and cost needed to meet modern performance standards was nil.

MAubrey
24-Sep-2018, 18:28
And it's only been in recent years that small format lenses have achieved this kind of coverage.

Canon 11-24mm: ~127%
Voigtlander 12mm: ~122%
Sigma 12-24: ~122%
Sony 12-35mm: ~122%

And the widest of small format lenses:

Voigtlander 10mm: 130%

Any of these lenses would be stupidly larger if they were upsized to 4x5.

Mark Sampson
24-Sep-2018, 19:49
I suppose the demand for lenses that cover 11x14 has been very small since, say, WWII. And the total market for lenses that cover 11x14 must also have been quite small, and declining with the rise of enlarging after, say, WWI.
What would have been the professional market for such a wide lens? Photographers shooting architectural interiors were likely content with 8x10. Scientists, perhaps? Very few of them. Industrial shooters? Again, 8x10 would have done the job. Banquet specialists? There's a possibility. Landscape photographers? A mere handful. Such lenses were probably very difficult to design, and very expensive to produce. With the rise of computer-designed optics, better types of glass, and the huge increase in precision manufacturing capabilities have made the lenses mentioned above by MAubrey possible. Plus the competition between camera companies, of course.
Greg, someday I hope you'll post a photograph made with your Gray No.5. Maybe even compared to the same view done with a less-wide lens?