Series V Protar all it's cracked up to be?

[Kerry L. Thalmann]

Robert,

Of the older wide angle designs, the Series V Protars are pretty good. That is to say, they aren't as good as the more modern Biogon derivatives, but still plenty good for contact printing - at least in terms of sharpness. They have three big advantages:

1) They are TINY - especially compared to a modern wide angle of comparable coverage

2) They are affordable - again, a lot less bucks than a modern wide angle

3) They have huge coverage - up to 110 degrees when stopped down to f45

Concerning the coverage - the 183mm Series V Protar covers 8x10 wide open. Coverage inceases substantially when stopping down. Unlike modern wide angles, the Series V Protar suffers from significant field curvature. What this means is that to get both the center and corners sharp, when pushing the coverage, requires stopping down. To get the maximum 110 degree coverage will require stopping down to at least f45 for acceptable performance. To hit the corners of 7x17 straight on requires about 103 degrees of coverage. So, the 183mm Series V Protar should cover 7x17 with a little left over for movements.

The biggest disadvantages to this lens are:

1) Dim f18 max. aperture

2) Significant illumination fall-off when pushing the coverage

183mm is extremely wide for the 7x17 format. Illumination fall-off, in an ideal case, follows the cos^4 function - and these older lenses generally don't quite match the ideal case. So, you're looking at about 3 stops fall-off from the center to the corners with a 183mm lens on 7x17 - and that's straight on. Apply some front rise and the fall-off just gets worse.

I personally shoot 4x10 and the widest lens I use is a 110mm Super Symmar XL. This lens on 4x10 is almost as wide as a 183mm would be on 7x17. I find this focal length extremely wide for 4x10 and don't use it nearly as much as my 150mm - which still seems quite wide to me on 4x10. Unless you need a REALLY wide lens for your 7x17, you might consider something in the 240mm - 254mm (10") range. I would personally find something in that range a lot more useful, but that's just based on my personal preferences.

Kerry

[sanking]

What Clay said.

The 8X10 (183mm) Protar Series V will cover 7X17 if you are very careful at centering the camera and if you stop down to f/45 or f/64. Coverage on the corners is definitely better than the 210 f6.8 Angulon. The major issue is that the groundglass is very dark. OK if you are working out of doors, but very difficult indoors.

I own an 8X10 B&L Protar V, which I hade mounted in a Copal 0, and previously owned a 183mm Zeiss Protar V. They were virtually identical in coverage and performance so I sold the Zeiss specimen since I knew it would sell for more.

[John D Gerndt]

I can speak to the "look" aspect of the (for me) 143mm Protar V. Mine is uncoated and renders as such. It is softer in contrast but not sharpness, I mean the detail is there but it doesn't shout at you (nothing does at f64). I like it fine but I do feel the stated limits are appropriate.

Mine is stated as a full plate: 6 1/2" x 8 1/2" and that is where it starts to get beyond soft. The corners an a 8x10 are not acceptable, to me. Lots of people identify those stretched corners (coma?) as part of an old-fashioned image and true, it looks that way. I just don't call it usable coverage. If you have to have very wide, very well done you have to get an XL or a Grandagon.

For what it is worth, in outdoor work, I find the f18 is no issue.

Cheers,

[John D Gerndt]

I wish to clearify: stretched in the corners is also quite fuzzy, indistinct, smeared, exactly like what I see in the corners of old aplanats. I believe the name is coma from comet for the stretched "tail".

[Robert McClure]

Thanks very much to you all. Learning these things is a slow process but you have made it much easier!

[N Dhananjay]

Not much to add re the Protar.

The Radar is actually a knockoff of the Tessar. One of the elements is split. Gundlach apparently used a similar MO on the Turner Reich, which is a knockoff of the Protar VII, with one of the elements split to make it 5 elements instead of four.

Cheers, DJ

[tim atherton]

"The Radar is actually a knockoff of the Tessar. One of the elements is split. "

Really? It's a 7" lens and covers 8x10 quite easily ("Radar Anastigmat Extreme W.A. 8x10 f16 Gundlach") - how well at the edges I'll have to see, but I have plenty of room for a couple of inches rise/fall at least

One thing I heard was that it was a copy of the Ross 5 element design?

[Ernest Purdum]

I think there is some confusion here because of the name "Radar" being used for more than one lens design, much as "Ektar" covers several differing types.

[tim atherton]

Knoppow suggests the Gundlach Radar WA Extremes were probably Gundlachs version (often adapted enough to avoid patent infringement) of the Zeiss Protar and it probably has coverage of 90 degrees accroding to their catalogue

I can definately see 2+1 (bright+dim) reflections in one lens group and I'm 90% certain I can see 2+1 in the other.

It's probably one of Gundlachs late 1930's or early 1940's lenses apparently

[tim atherton]

"I think there is some confusion here because of the name "Radar" being used for more than one lens design, much as "Ektar" covers several differing types"

indeed - the Radar Anastigmant 4.5; Radar Telephoto Anastigmat F5.6; Radar Extreme Wide Angle F16 etc