Sinaron 5.6 / 210 mm Smallest Aperture

[NormaN]

Hello everybody

I just bought a nice and have a question about the smallest aperture f64.
As you can see in the photos, the stop at the largest aperture (i.e. diameter) is exactly at 5.6, the stop at the smallest aperture is somewhere at 64 +2/3, i.e. almost f90.

The aperture scale 0011.064 seems to be the right one (as far as I could compare with other images on the net).
Do any of you have just such a lens at hand? Does it look like that with your lens too?

NormaN

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[Greg]

Many of my lenses stop down to unmarked f/90, f/128, and even f/180 apertures. I have found these unmarked aperture settings OK to use for contact prints, but definitely not for negatives that will be enlarged unless you like a "pinhole lens" effect.

[Bernice Loui]

If the goal is "every item in the image to be in focus" do not stop down below f45. Exploit camera movements much as possible to used the largest taking aperture possible to achieve what is needed in the image to be in focus and no more. Ideally, for images like this the taking aperture typically goes from f16 to f32.

The f-stop scale stops at f64, typically even f64 on a modern LF lens would be rarely used if ever.


Bernice

[Bob Salomon]

If the goal is "every item in the image to be in focus" do not stop down below f45. Exploit camera movements much as possible to used the largest taking aperture possible to achieve what is needed in the image to be in focus and no more. Ideally, for images like this the taking aperture typically goes from f16 to f32.

The f-stop scale stops at f64, typically even f64 on a modern LF lens would be rarely used if ever.


Bernice

And learn where to place the focus to maximize dof.

[NormaN]

Many of my lenses stop down to unmarked f/90, f/128, and even f/180 apertures. I have found these unmarked aperture settings OK to use for contact prints, but definitely not for negatives that will be enlarged unless you like a "pinhole lens" effect.

Hello Greg Thank you for your tips!

This means that there is no fault on the aperture / aperture scale if it closes more than specified by the manufacturer ... I also found an example on Ebay where the 5.6 aperture is exceeded (example Sironar W 210 mm, Copal 3, see picture). Isn't there a "mechanical" stop at the largest aperture? I'm still a beginner and have not realized that the shutters are sometimes equipped with the "wrong" aperture scales or that the aperture scales are sometimes even missing. Can you explain to me what it means to use a small aperture for contact sheets? I would like to start with 5x7 contact sheets.

NormaN

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[NormaN]

If the goal is "every item in the image to be in focus" do not stop down below f45. Exploit camera movements much as possible to used the largest taking aperture possible to achieve what is needed in the image to be in focus and no more. Ideally, for images like this the taking aperture typically goes from f16 to f32.

The f-stop scale stops at f64, typically even f64 on a modern LF lens would be rarely used if ever.


Bernice

Hi Bernice

Thank you for your input. My question was more about the mechanics. With 35mm lenses I was used to the fact that there was a physical stop at the largest / smallest aperture. The deviation from the aperture scale on large format lenses made me feel insecure: is the aperture set correctly or is there some kind of shift

NormaN

[NormaN]

And learn where to place the focus to maximize dof.

Hello Bob

I'm still at the very beginning and haven't developed a single negative yet. I've just managed to bring all the necessary components together. The 5x7 film is on its way ... Now I can start learning by applying it

NormaN

[Dan Fromm]

Pardon me for jumping in. It isn't a question of wrong scales. Leaf shutters' diaphragms typically go from fully open to "very small opening." They don't have lens specific stops. For some lenses, fully open is larger than needed for the entrance pupil to be fully open. This happens most often with lenses that have small maximum apertures.

About stopping down. Resolution is limited by diffraction. The greatest resolution possible is approximately 1500/(f/ number). For a hypothetical computationally easy example, at f/150 the diffraction limit is 1500/150 = 10 line pairs/mm. This is the maximum possible, but is at very low contrast. At normal print viewing distance most people see 8 lp/mm in the print as sharp. So, practically speaking, a shot taken at f/150 will look sharp (just barely) if contact printed but will look soft if enlarged.

[Bernice Loui]

LF lenses in shutter use what are essentially generic shutters that are not specific to any given lens formulation-design. This allows some LF lens cells to be transferred to a new shutter if needed and more. This is not typically true with brand specific roll film lenses designed for a specific brand's camera body (there are exceptions in the film-video world of lenses where classic lenses get a new housing).

For a given lens as exampled by your 210mm f5.6, there will be residual mechanical aperture travel that exceeds the aperture scale markings. A more extreme example would be a modern wide angle lens in shutter where there is a significant blank area with equally significant travel of the aperture control lever before the aperture marking of the lens becomes engaged.

Adding to the insecurity could be the lack of click stops for the aperture exampled by a Copal shutter which has smooth and continuous aperture control lever travel, no click stops. The aperture on the Copal is camed to linearize the aperture scale making setting to fractions of an f-stop easier.


Bernice




Hi Bernice

Thank you for your input. My question was more about the mechanics. With 35mm lenses I was used to the fact that there was a physical stop at the largest / smallest aperture. The deviation from the aperture scale on large format lenses made me feel insecure: is the aperture set correctly or is there some kind of shift

NormaN