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View Full Version : Apo-Sironar-N 1: 5,6 210mm remarkable unsharpness at the border?



HorstS
18-May-2013, 08:31
Hello,

have this glass of Rodenstock on a Technika III 4x5 in use; came in Copal 1.
Since it was the first lens to this camera, I was wondered on the
"Difficulties" when adjusting the image. For a reasonably sharp
Image I had to stop down to at least 1:8, and then it was only in the middle
sharp.
I thought it might have been a typical 4x5 issue (poor focusing screen?), since I have no experience with 4x5.

In meantime, I own a Super-Angulon 90mm 1:8. And now I realize, focusing
the image is no problem. Sharp image at open aperture into the corners.

Shots with both lenses reflect that again:
From Super-Angulon everything as expected, from Rodenstock blatant edge blur,
and that at f 32.

So something must be wrong with this lens.

Question - who could safely conclude (only Rodenstock?)
- can such a glass be ever decentered / be centered?
- can be interchanged the hind limb (I had at least expected a lens number as on front element, but can not find)?
- Under the front element is a thin intermediate ring / washer. Can it be that maybe more belong there, that have been lost?

Maybe one of you has experience in this regard,
any response I am pleased.

Kind regards,
Horst.

E. von Hoegh
18-May-2013, 08:36
Something is drastically wrong with that lens. I'd vote for incorrect reassembly, or missing elements. A Plasmat (the type of your lens) will have in each cell a cemented outer pair, an airspace, and a single inner element. This lens should be sharp from center to edge at f:5.6.

Peter Yeti
18-May-2013, 09:25
I only can back what E. von Hoegh wrote. I use a Sironar-N 5.6/210 since about 20 years and it is a really sharp lens throughout the image circle. The shim between front element and shutter is standard, usually it is 0.3mm or sometimes 0.2mm. But even if the shim was missing, you'd hardly notice it at f32 unless you scrutinize the edges very carefully. My guess is that something else must be really wrong with the lens that is not so obvious. Depending on your budget, it might be worth calling Rodenstock and probably sending it in. If it is only a matter of adjustment, the repair may be cheaper and the outcome more certain than hunting for a cheap replacement at a well-known auction site.

Good luck that it's nothing big!

Leigh
18-May-2013, 09:48
I have that lens (currently listed for sale). It's tack sharp.

What shutter is yours mounted in? It sounds like the cell spacing is wrong.

- Leigh

HorstS
18-May-2013, 10:34
Thank you so much for your nice responses. Ill try a call at Rodenstock.

@Leigh It is mounted in a Copal 1. There is only a rather thin spacer under the front cell.

Peter Yeti
18-May-2013, 11:23
If you have a way to accurately measure the overall length of the lens in it's shutter, you can compare it to the correct length of 66.0mm. But I would be surprised if it was only a simple spacing problem.

HorstS
18-May-2013, 13:43
@ Peter The overall length is 65,8 mm. I think the missing 0,2 mm should not be that problem ...

Leigh
18-May-2013, 13:54
@Leigh It is mounted in a Copal 1. There is only a rather thin spacer under the front cell.OK Mine is also in a Copal 1.

- Leigh

Gem Singer
18-May-2013, 17:13
Did you remove the tiny index screw prior to mounting the lens on the lens board?

HorstS
19-May-2013, 07:41
@ Gem : That is an interesting question, course I dont neither know where this screw should be nor I have removed some thing.

The lens came on a Horseman board. I removed front and back element, unscrewed the shutter and did this in reversal order on a Technika III board.
Did I something wrong?

Leigh
19-May-2013, 07:53
The small screw is on the back of the shutter, at the 12 o'clock position when the shutter is oriented normally.

Its purpose is to prevent the shutter from rotating in the lensboard and coming loose.

For it to work properly, a small notch must be cut in the lensboard, on the edge of the mounting hole.
This is most easily done before the mounting hole is bored. It can be cut afterwards with a small file.

Many people remove this screw because they don't want to be bothered cutting that little notch.
The screw cam be removed with a small flat-blade screwdriver.

If the screw is in place but there's no notch to accommodate it, the shutter will sit at a very pronounced angle to
the lensboard, not flat like it should. The problem will be quite obvious, with the top of the shutter sticking out.

- Leigh

Gem Singer
19-May-2013, 07:58
Horst,

Remove the shutter from the Technica board. Run your finger around the rear of the shutter.

If you feel a slight protrusion, remove the index scew, Then, remount the shutter.

Bob Salomon
19-May-2013, 08:50
The small screw is on the back of the shutter, at the 12 o'clock position when the shutter is oriented normally.

Its purpose is to prevent the shutter from rotating in the lensboard and coming loose.

For it to work properly, a small notch must be cut in the lensboard, on the edge of the mounting hole.
This is most easily done before the mounting hole is bored. It can be cut afterwards with a small file.

Many people remove this screw because they don't want to be bothered cutting that little notch.
The screw cam be removed with a small flat-blade screwdriver.

If the screw is in place but there's no notch to accommodate it, the shutter will sit at a very pronounced angle to
the lensboard, not flat like it should. The problem will be quite obvious, with the top of the shutter sticking out.

- Leigh

Rodenstock does not use the centering screw on their shutters and Linhof does not key their lens boards to the screw.

It sounds like he bought a used lens of unknown history that has probably received, at least, a good impact which may or may not be evident on the lens. Or the lens has the wrong rear group.

HorstS
19-May-2013, 10:45
Thanks a lot for all your nice advises and hints.
There is no index screw (though I can see the thread for it) , the shutter sits plane on lensboard.

@ Bob: Im curious about no serial-number on the rear element, though there is one on the front element. Is that correct?

Horst.

Bob Salomon
19-May-2013, 13:56
Thanks a lot for all your nice advises and hints.
There is no index screw (though I can see the thread for it) , the shutter sits plane on lensboard.

@ Bob: Im curious about no serial-number on the rear element, though there is one on the front element. Is that correct?

Horst.

They don't put a serial number on the back

Peter Yeti
19-May-2013, 14:23
You could measure the outer diameter of the rear element if you want to make sure that the rear element is not from a different kind of lens. The 5.6/210 should have a diameter of 60mm. The 5.6/180, which also fits into a #1 shutter, has 51mm diameter. By comparison, the Symmar-S 5.6/210 has 57mm and the corresponding 5.6/180 is 50mm. I don't have the data for other lenses but if you measure 60mm you have a good chance that your lens is a complete Sironar-N 5.6/210.

HorstS
19-May-2013, 15:20
Thanks again !!

@Peter : the outer diameter is rather exactly 60 mm. That looks at least fine. Ill call Rodenstock at Tuesday, tomorrow is still holiday in Germany.

Horst.

Ivan J. Eberle
19-May-2013, 15:47
Used but mint condition copies of this lens are typically selling for $250 or less these days, with a working shutter, should you need to replace it. Mine is the Caltar II-N branded version, which I've found to be a fabulous, extremely very sharp optic. It hase a huge amount of coverage, enabling large camera moves.

Leigh
19-May-2013, 18:02
Rodenstock does not use the centering screw on their shutters...Rodenstock does not make shutters.

Copal shutters all have the threaded hole for the anti-rotation pin.

Whether or not it's installed is a separate question.

- Leigh

Bob Salomon
20-May-2013, 06:53
Rodenstock does not make shutters.

Copal shutters all have the threaded hole for the anti-rotation pin.

Whether or not it's installed is a separate question.

- Leigh

Check out the Rodenstock eShutter then. Controlled by an iPhone, iPad or iPod Touch. The App is on the Apple Store.

Leigh
20-May-2013, 07:01
Sorry, Bob. I was talking about real shutters, not cell phone toys.

- Leigh

Bob Salomon
20-May-2013, 07:08
Sorry, Bob. I was talking about real shutters, not cell phone toys.

- Leigh

It is a very real shutter. Also very modern.

Now that Copal has discontinued the manufacturing of shutters the only current production shutters are the electronic ones like Rodenstock's, Rollei's and Schneider's.

Leigh
20-May-2013, 07:11
Also insanely expensive.

I'm talking about shutters that real photographers here on the Forum use, not shutters
that people see in display windows and at Photokina.

In my earlier post (#19) I specifically said my comments were about Copal shutters, which
are the shutters most commonly used among our members.

- Leigh

E. von Hoegh
20-May-2013, 07:34
Check out the Rodenstock eShutter then. Controlled by an iPhone, iPad or iPod Touch. The App is on the Apple Store.

This one? http://www.bhphotovideo.com/c/buy/Large-Format-Lens-Shutters/phd/4291256937/ci/44/N/4077634427

Leigh
20-May-2013, 11:37
This one? http://www.bhphotovideo.com/c/buy/Large-Format-Lens-Shutters/phd/4291256937/ci/44/N/4077634427
Like I said, insanely expensive:
$2700 for the shutter
$2600 for the control box
$.153 for a 1-foot X-sync cable ???!!!
$..52 for a USB cable
------
$5505 for a single shutter for one lens

These people should be in jail. That's highway robbery.

Just shows what happens when a company develops a monopoly.

- Leigh

Bob Salomon
20-May-2013, 12:08
Like I said, insanely expensive:
$2700 for the shutter
$2600 for the control box
$.153 for a 1-foot X-sync cable ???!!!
$..52 for a USB cable
------
$5505 for a single shutter for one lens

These people should be in jail. That's highway robbery.

Just shows what happens when a company develops a monopoly.

- Leigh

Not an X synch as you are thinking of. That is a cable that goes from a digital back to the shutter controller. The flash synch is the same type of cable as other shutters would use.
Also with all the electronic shutters a control box has to be bought with the first shutter. All additional shutters use the same control box, battery, charger, etc. So the first shutter is much more then the additional ones.
And like it or not, that is what is currently manufactured in shutters. There is no current manufacturer of mechanical shutters today.

Ivan J. Eberle
20-May-2013, 21:00
There is no current manufacturer of mechanical shutters today because the tremendous surplus of used ones (many in perfectly good condition, that come with astoundingly good lens cells, and which got dumped in the marketplace by professionals as they fled to digital as if taking flight from a burning building a half-dozen years ago) represents a 25, 50, or perhaps 100 year supply at present rates of consumption.

Leigh
20-May-2013, 22:33
Not an X synch as you are thinking of. That is a cable that goes from a digital back to the shutter controller.
The B&H page that was linked earlier describes it as an "eShutter X-Adapter Cable (1')", which is where I got the X reference.

In any case it's $10 worth of connectors with a $2 piece of wire between them, selling for $153.

- Leigh

HorstS
21-May-2013, 12:45
Hi,

Today I visited my local photo-shop (driven by a graduate photo-engineer ):

And lo and behold: A lens / lens group was installed incorrectly!
Now I can also see the image of which I have dreamed on the focusing screen ... ;-)

Thank you again for all your posts
as they have also helped to find the track ...

regards,
Horst.

Leigh
21-May-2013, 15:51
Great news, Horst. Congratulations!

- Leigh