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erian
14-Feb-2020, 03:29
I tried to find optical diagrams for Pinkham and Smith products but came back empty handed.

Anybody here can share some bits about the design of these lenses (any of them)?

Greg
14-Feb-2020, 05:54
"In the early years of the present century the Wollensak Optical Co. manufactured two soft-focus Portrait lenses. the f/6 Veritar and the f/4 Verito. Both were simple uncorrected lenses of the Periscopic (two single meniscus elements) type. The degree of softness could be varied by stopping down the lens. Similar soft focus lenses were made by Pinkham and Smith of Boston." "In 1933 Kodak patented a modification of the Periscopic type in which the front component was split into two parts by a plane-parallel airspace, the width of which could be varied (Kodak Bimat & Twindar lenses)" Personally never heard of Kodak's Bimat & Twindar lenses. from the book A History of the Photographic Lens by Kingslake

Mark Sawyer
14-Feb-2020, 11:19
The Verito and Veritar weren't "of the Periscopic (two single meniscus elements) type." Both had a cemented achromatic doublet at the rear and a single meniscus up front.

P&S went through several designs, others know them better...

erian
14-Feb-2020, 12:05
The Verito and Veritar weren't "of the Periscopic (two single meniscus elements) type." Both had a cemented achromatic doublet at the rear and a single meniscus up front.

P&S went through several designs, others know them better...

Pinkham & Smith Series IV Visual Quality 13" that Jim Galli has/had http://tonopahpictures.0catch.com/PinkhamSmithLens.html has doublet both ends (similar to Rapid Rectilinear).

Pinkham & Smith Semi-Achromatic Series I has only one lens group containing doublet (a semi achromatic doublet :)) http://tonopahpictures.0catch.com/Pinkham-Smith/2_Serie_I-3_Comparison/2_Serie_I-3_Comparison.html https://antiquecameras.net/softfocuslenses.html

What would be more interesting for me is to know more details about the glass and its layout (like in http://www.dioptrique.info/). We know that P&S VQ is no RR and P&S SA is no usual doublet.

erian
14-Feb-2020, 13:13
"In the early years of the present century the Wollensak Optical Co. manufactured two soft-focus Portrait lenses. the f/6 Veritar and the f/4 Verito. Both were simple uncorrected lenses of the Periscopic (two single meniscus elements) type. The degree of softness could be varied by stopping down the lens. Similar soft focus lenses were made by Pinkham and Smith of Boston." "In 1933 Kodak patented a modification of the Periscopic type in which the front component was split into two parts by a plane-parallel airspace, the width of which could be varied (Kodak Bimat & Twindar lenses)" Personally never heard of Kodak's Bimat & Twindar lenses. from the book A History of the Photographic Lens by Kingslake

Interestingly Vademecum is also not sure about these lenses.

Smith Series 1 - It is a single achromatic or semi-achromatic lens
Smith Series 11 - This was a semi achromatic doublet ie only part corrected for colour.
Smith Visual Quality - It may be a doublet or periscopic?
Smith 'Synthetic' Lens - It was a single combination, and very soft.
Wolfe Artistic Lens - This was a diffusion attachment of two or more glasses of different dispersion cemented together. The iris controls sharpness.