Protars

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Susie Frith
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Joined: Tue Jul 26, 2011 5:28 pm Etc/GMT-1+01:00

Protars

Post by Susie Frith » Sun Aug 21, 2011 3:00 pm Etc/GMT-1+01:00

Hi all,

Andrew Plume asked to see some pictures of my Protar set (why, I'm not sure!), so here they are, together with some rambling of mine.

Image

The first one shows the complete outfit, as it were. The set consists of the original barrel and three Series VII Protars. These are 224mm, 285mm and 350mm focal lengths. In Zeiss terms this is a Protar-set C, for 13x18cm (5x7") and would normally be supplemented with a Series V Protar No. 2 or No. 3 (112mm or 141mm f/18) wide angle lens.
S.K. Grimes, in the USA, mounted the lenses into a Copal 1 shutter, made two mounting rings, a spacer and Linhof lensboard adapter.

Image

Here it is mounted on a Linhof 54 panel (with missing badge!), in the panel adapter, on my Linhof 5x7 Technika V.

Image

And here it is screwed into the mounting ring on a lens panel, using the spacer, on my Sanderson half-plate camera. The spacer is needed to clear the clamping screw for the cross-front. The Sanderson is a super camera for this lens! Very quick to erect, and very light too.

The lens itself was made by Krauss of Paris. Each "element" is a Series VII Protar lens f/12.7, made of four glass components cemented together. Two Series VII's mounted in a barrel or shutter makes a Series VIIa f/6.3 if they are the same focal length, or f/7 or f/7.7 if they are of unequal focal length. All rather confusing really!

Combining the Series VII's give the following focal lengths:
The 285mm Protar VII and the 224mm Protar VII gives a 143mm Protar VIIa.
The 350mm Protar VII and the 224mm Protar VII gives a 156mm Protar VIIa.
The 350mm Protar VII and the 285mm Protar VII gives a 178mm Protar VIIa.

The Series VII Protars cover 40 to 50 degrees and the Series VIIa Protars 85 to 90 degrees.


The iris on both the barrel and Copal shutter is calibrated from 28mm down to 3mm diameter and not in f/stops. This is because the ratio depends on the focal length of the lens. To make things quick and easy in the field I have compiled a chart showing the relationship between the six focal lengths available, f/stops (for the light meter reading), diameter of the iris, and the depth of field/bellows extension difference.

So in use, once the image is composed and after using any adjustments to help focusing, I focus on the item in the scene needing the greatest bellows extension (not always the nearest thing if adjustments have been used). I then note the position of the rear standard.

I then focus on the item in the scene needing the least bellows extension, using the rear focusing, and measure the distance between the two points.

The camera back is then moved half way between the two readings, which you will all know won't be focused on the part of the scene half way between the two items focused on before! As the Linhofs only have front focusing, I have a millimeter scale where the distance scale usually is, to do the measuring. If you know what I mean, fine, if not, it doesn't matter!

The difference between the two readings (it might be, say, 6mm when using the 178mm combination on a 5x7 film) is then checked on the chart, which indicates an iris diameter of 8.5mm is needed for the whole scene to be in focus, which for this focal length (178mm) is f/21. This is checked on the exposure meter for the required shutter speed. Easy! But then "easy" is relative!


The Series VII and VIIa Protars are very usable lenses and shouldn't be relegated to collections just because they are not coated or because they were designed in the mid 1890's. After all, the Zeiss Planar first came out in 1897 and that is still being made!

Other Protars you might come across are the Series V, and should not be confused with the Series VII and VIIa. These are a whopping (sic) f/18 (NOT f/1.8!) with an angle of about 110 deg. and were recommended as a complementary wide angle lens to a convertable set, as well as being wide angle lenses in their own right. The Series V are not convertable though, and to be honest became redundant when the Schneider f/6.3 Angulon came out. There is also the Series IIIa Protars of f/9. These are modest wide angles of 97 deg, but like the Series V's can only be fitted onto, not into, a shutter, as they are so small.

Hope this lot is of some interest.

Susie
Last edited by Susie Frith on Sat Aug 27, 2011 9:04 am Etc/GMT-1+01:00, edited 1 time in total.

Andrew Plume
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Re: Protars

Post by Andrew Plume » Sun Aug 21, 2011 4:56 pm Etc/GMT-1+01:00

Susie Frith wrote:Hi all,

Andrew Plume asked to see some pictures of my Protar set (why, I'm not sure!), so here they are, together with some rambling of mine.


Hi Susie

thanks for posting all of this and the photos :D

the reason I asked is that I feel that we should have (far) more of this sort of stuff on here i.e. older lenses and a decent commentary too if possible, so that's excellent stuff :)

best

andrew

Charles Twist
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Re: Protars

Post by Charles Twist » Sun Aug 21, 2011 5:22 pm Etc/GMT-1+01:00

Yes, I thought that was interesting.
Thanks,
Charles

Susie Frith
Posts: 53
Joined: Tue Jul 26, 2011 5:28 pm Etc/GMT-1+01:00

Re: Protars

Post by Susie Frith » Sat Aug 27, 2011 9:06 am Etc/GMT-1+01:00

Oops! I was messing about with Photobucket and managed to move the pictures to another album. :oops:

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