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View Full Version : Which lens designs are least 'objectionable' nearly wide open?



Wally
5-Jan-2009, 00:22
I hear that a lens is in it's 'zone' stopped down 2-3 stops from wide open, where it will be 'within it's specs'.

What I'm curious is what are the 'qualities' of a lens as it's opened up, for the different lens designs? How, for example, does focus soften as a triplet like a Geronar is opened up? Is it 'better' or 'worse' than a tessar? What are the focus and coverage issues for triplets, tessars, plasmats, etc like as the lens is opened up? What other issues are there?

My interest (right now) is in photographing people - environmental portraits to head shots, and want to constrain depth of field in the series.

Brian Stein
5-Jan-2009, 01:37
Look at Chris Perez's experiments at http://www.hevanet.com/cperez/test/BigMash210.html where he compares tessar, triplet and plasmats wide open.

CCHarrison
5-Jan-2009, 05:13
The most celebrated lens for wide open performance is the Petzval design. See this page for more info:

http://www.antiquecameras.net/petzvallens.html

Lack of DOF is the biggest problem with any fast, wide open lens - especially - in the larger formats....

Dan

Jim Galli
5-Jan-2009, 09:48
impossible to answer because what is objectionable to you may be the very thing the next guy is looking for.

CG
5-Jan-2009, 11:05
.... Lack of DOF is the biggest problem with any fast, wide open lens .... Dan

Or, biggest opportunity. Depends upon what one wants in a given situation.

C

Wally
5-Jan-2009, 15:43
impossible to answer because what is objectionable to you may be the very thing the next guy is looking for. I like your petzval protraits. It's a look I want to get near.

They're in barrels, right? Do you use a packard shutter, a speed graphic focal plane shutter, or what?

Jim Galli
5-Jan-2009, 16:04
Hi Wally. Thanks. Well, if you like the Petzval look it is at it's very best wide open and gets objectionable as you stop down :D . Yes, I'm in my comfort zone with an 8X10 that has a Packard inside. I seem to get the most enjoyment from contact prints so it is a good combination for me. I also use a 5X7 Speed Graphic with focal plane shutter for some of the smaller lenses and it lets me get in the speed ranges of modern films.

Wally
5-Jan-2009, 16:05
The most celebrated lens for wide open performance is the Petzval design. See this page for more info:

http://www.antiquecameras.net/petzvallens.html

Lack of DOF is the biggest problem with any fast, wide open lens - especially - in the larger formats....

Dan
I've been shooting my portraits with a 300mm Fujinon T, a tessar design. I've been shooting with the background at least a yard from the subject, f/16 or f/22 @ 1/30th, window light and a reflector for illumination.

Some lenses' sharpness rolls off faster as one views the areas away from the center of the image (sharp knee in lp/mm), some just go all creamy smoothly (linear tapering off of sharpness), some are somewhat soft and get sharper the more you stop down, but are not really sharp enough in the center at f/11, making it look like I didn't focus correctly or look like the subject moved. I'm looking for one that is reasonably sharp in the center at two stops down from wide open, and are sharp enough for an 8x10 2x enlargement when stopped down only one stop, and then gets as soft as it wants as much as two inches from the edges.

Gordon Moat
5-Jan-2009, 21:04
I like your petzval protraits. It's a look I want to get near.

They're in barrels, right? Do you use a packard shutter, a speed graphic focal plane shutter, or what?

Hello Wally,

You might be interested in this thread:

http://www.largeformatphotography.info/forum/showthread.php?t=43976

I discuss a solution I came up with for my ancient lens. It works fairly nicely.

Ciao!

Gordon Moat Photography (http://www.gordonmoat.com)

John Kasaian
5-Jan-2009, 21:15
The 300 f/9 Nikon "M" is frighteningly sharp when opened up, if sharpness is what you mean by "less objectionable." It is a tessar and I've seen similar results with other tessars (especially Kodaks,) though I can't say that such is the norm across the board with all tessars (because I haven't shot with every tessar!) A great many aerial lenses are tessars though, and they were usually shot at more open apertures due to the fast shutter speeds and often heavy filtration that needed to be compensated for.

aduncanson
6-Jan-2009, 07:13
The Fujinon T 300mm, f/8 T is reportedly a telephoto design, not a tessar. If it is a telephoto, it will focus at infinity with considerably less than 12 inches of bellows draw. I would guess that the characteristics of a telephoto might be quite a bit different than those of a tessar. I believe that the Fujinon C 300mm f/8.5 is a tessar.

Emmanuel BIGLER
6-Jan-2009, 08:22
Hello all and best wishes from France for the New year !

I believe that the Fujinon C 300mm f/8.5 is a tessar.
As a democrat, I respect all beliefs ;-) however, this reference document ...
http://www.thalmann.com/largeformat/c.htm
..suggests that Fujinon-C view camera lenses are a kind of a 4-element un-cemented dialyte design; not quite a symmetrical dialyte like the beloved apo-ronar, but with the same arrangement of un-cemented elements ( + - - +) ; whereas the good ol' tessar (and Nikkor-M) is (+ - (+-) ) with a cemented doublet at rear.

If the Nikon-M is very sharp wide open, probably the reason is that it is a specially designed tessar formula with a restricted maximum aperture @f/9 ; the original 1902 tessar opened @6.3 ; in 35 mm format tessars were designed at maximum f:2.8 more than 60 years ago, in medium format they already opened at 3.5 in the thirties, and f/4.5 was standard for old-style view camera tessars and xenars in 9x12 ,4x5" and above... but at the time, fine-grain films were not as fast as nowdays and photographers did not demand a wide coverage. The last generation of general-purpose Schneider 210mm xenars for 5x7" opened @6.1, probably to allow a better coverage with a formula capable of opening@4.5 in the previous versions...

I'm sure that many modern view camera lenses for 9x12 and above can be used wide open if you do not ask for maximum sharpness and coverage, but my understanding is that engineers opimized view camera lenses for maximum image performance at best f-stop which can be f/16 or f/22 since those lenses were aimed mostly at static subjects or moving subjects frozen by a powerful strobe in the studio.
So if you ask the engineers if you are allowed to use their view camera lenses wide open, their answer will probably be : yes ...(I'm sure that engineers cannot complain about what the end user does, they _have_ to do what the customer asks for ;) )...
but, the engineers would probably (kindly) object : if you had asked us to design something outstanding @f/5.6, we would have designed something else ! (and something more expensive, of course ;) )

An interesting issue is what happens with wide-angle view camera lens designs like the classical F/8 super-angulon or the more recent f/6.8 6-element grandagon-N (I have both the 75 and 90 and I'm amazed how sharp a 6-element wide-angle lens can be !)

In fact those lenses are already extremely sharp at f/11 (never tried 6.8 ! a shame !) , stopping them down increases their coverage (and even-ness of performance through the field)
In fact you can use a 90 mm f/8 super-angulon wide open if you only use it for 6x9 on rollfilm, but the image performance will probably not be as good as a 80 mm Zeiss planar (the 80 does not quite cover 6x9) or a 100 mm Zeiss planar (actually covers 6x9) both planars stopped down to f/8 : @f/8 the 80mm 7-element planar has been tested by Chris Perez and is supposed to resolve close to 100 cycles/mm, a figure that the f/8 super-angulon could hardly reach (yes, agreed, 100 cy/mm are probably useless in real life, but I know that many forum readers like the mere idea of it ;) )

Wally
8-Jan-2009, 00:00
The Fujinon T 300mm, f/8 T is reportedly a telephoto design, not a tessar. If it is a telephoto, it will focus at infinity with considerably less than 12 inches of bellows draw. I would guess that the characteristics of a telephoto might be quite a bit different than those of a tessar. I believe that the Fujinon C 300mm f/8.5 is a tessar. You're right. I pulled it out and read it more carefully. It's a Fujinon-L 300mm f5.6. A single-coated tessar.

I don't know if the C is a tessar, but it looks like it's got the image circle of a one. It's smaller (fits in a Copal 1 vs. the L's Copal 3, and I think it's a newer design than the L.

aduncanson
8-Jan-2009, 07:14
A Fujinon-L, that makes sense. Mr. Bigler already convinced me that the Fujinon-C is a dialyte (and helpfully chastened me to avoid posting my assumptions without checking references in the future.)

Ole Tjugen
8-Jan-2009, 09:09
... The last generation of general-purpose Schneider 210mm xenars for 5x7" opened @6.1, probably to allow a better coverage with a formula capable of opening@4.5 in the previous versions...

I have a feeling that the main reason for the f:6.1 max aperture is so that it would fit into a #1 shutter instead of the #3 necessary for the f:4.5 Xenars. Similarly the f:5.6 150mm Xenars take a #0 shutter, while the f:4.5 takes a #1.

Arne Croell
8-Jan-2009, 10:27
but, the engineers would probably (kindly) object : if you had asked us to design something outstanding @f/5.6, we would have designed something else ! (and something more expensive, of course ;) )
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I think they did - for a little while in the 1950's and 1960's. Those where the Schneider Xenotars f/3.5 135mm and f/2.8 150mm which were offered in parallel to their own Symmars of the same focal lengths, and also the Zeiss lenses made for Linhof: Biogon 75mm, Planar 135mm, Sonnar 250mm.

A case in point are also the corresponding lenses from Zeiss Jena (Lamegon, Biometar) that never made it to the market, for the Czech "Grandina Camera". When I did my research at the Zeiss jena archives for the VC article about them, I found the Zeiss resolution tests for their lenses including comparisons with the competition. They never bothered to test the 135mm with apertures smaller than f/11, the Lamegons and the 210 Biometar only to f/16.

Frank Petronio
8-Jan-2009, 12:02
I know nothing about optics, but when I shot 8x10 portraits I used either a 300/5.6 Xenar or a 14" Commercial Ektar at or near wide open and both lenses were very pleasing, with tack sharp in-focus points and smooth transitions to a creamy, smooth bokeh that blended harsh lines together (instead of making them look harsher). Both had round aperture blades too.

Ole Tjugen
8-Jan-2009, 14:54
Here's an example shot with a 300mm f:4.5 Xenar, wide open on 5x7" film using the maximum swing and a hint of tilt on a Linhof Technika 13x18.

It shows, after careful inspection, that "front" and "back" bokeh (here right and left, respectively) are different, so that a blurry background is smoother than a blurry foreground.

http://www.bruraholo.no/bilder/POP2.jpg

Mel
6-Jul-2010, 22:43
impossible to answer because what is objectionable to you may be the very thing the next guy is looking for.

Love that vacant Campbell & Kelly building shot with the Cham and these lenses:

Goerz WA Dagor 4 1/4" @f22 1/2
Wollensak Velostigmat Series 1A 222mm f7 coated @f16
NoName 4 1/2" Meniscus in Prontor shutter wide open

Where is this building located?

It's better being here than in a museum. :D

Note to self: stroll around more before bedtime tomorrow

Mel
6-Jul-2010, 22:44
Here's an example shot with a 300mm f:4.5 Xenar, wide open on 5x7" film using the maximum swing and a hint of tilt on a Linhof Technika 13x18.

It shows, after careful inspection, that "front" and "back" bokeh (here right and left, respectively) are different, so that a blurry background is smoother than a blurry foreground.

http://www.bruraholo.no/bilder/POP2.jpg

Wow, remarkable.

Jim Galli
7-Jul-2010, 06:10
Love that vacant Campbell & Kelly building shot with the Cham and these lenses:

Goerz WA Dagor 4 1/4" @f22 1/2
Wollensak Velostigmat Series 1A 222mm f7 coated @f16
NoName 4 1/2" Meniscus in Prontor shutter wide open

Where is this building located?

It's better being here than in a museum. :D

Note to self: stroll around more before bedtime tomorrow

Thank you for the kindness. The Campbell & Kelly building was the Chevrolet dealership in Tonopah Nevada until 1966. It sits mostly vacant on Main St. (hwy 95) in Tonopah.