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-   -   Rolleicord Va - loose taking lens front element and unsharp photos (http://www.rangefinderforum.com/forums/showthread.php?t=167004)

albireo 12-06-2018 07:19

Rolleicord Va - loose taking lens front element and unsharp photos

A while ago I purchased a Rolleicord Va in seemingly amazing condition. Great lens, functioning shutter, no rust, no peeling of the leatherette etc.

On further inspection though, I found that the front element of the Xenar taking lens was loose. No signs of tampering are visible on the rim of the element so I've been assuming it's something that just happens on these old cameras. I very carefully fully tightened the element until no further screwing action was possible, and went ahead to shoot a test roll.

To my disappointment, the pictures are not as sharp as I was expecting. For reference, I own a Yashicamat 124G, too, and the results I get out of the 124G are noticeably sharper. Now, I *know* a Rolleicord Va can easily be a match for Yashicamat 124G: for a brief time I owned another Va (which I stupidly returned, because it came with a 16 frame adapter and no 12 frame adapter). That Rolleicord gave me excellent, sharp pictures, equal or superior to those produced by the 124G.

Going back to the current Va, the photos are ever so slightly out of focus and noticeably soft, even at f/8, in the corners. I will clearly have to check the focus at infinity, and potentially re-collimate viewing and taking lenses. I do not notice lack of parallelism in the front standard wrt the camera body.

My question could be: has anybody had experience in collimating both lenses in a Va? Will just unscrewing both front elements to reach an agreement at infinity do? I fear it won't because unscrewing the front elements will result in them being loose, which means the collimation will be lost due to movement in time. Any better solutions for this?

Sarcophilus Harrisii 12-06-2018 07:43

It's very late for me, so I'll be brief. But you must remove the front mount from the shutter, it is in two parts threaded together, and locates the front two lens pieces in position. It should easily unscrew if needed, being a Va there may even be two very small holes for a lens spanner but these are not generally needed. Once the front cells are correctly installed in their mount assuming the rear cell is in satisfactory order the front mount should be fastened back into the shutter all the way until moderately firm. You'll then need to check the infinity adjustment of the taking lens with a ground glass and loupe, and correct it, if needed, before you consider adjusting the viewing lens, which should always be done last.

There are more detailed comments about calibrating focus of a Rolleicord on this site—I've written some of them—so do a search for relevant posts for elaboration on the above.

Steve M. 12-06-2018 08:00

Stopping down to f8 is not going to give you sharp corners w/ a medium format camera. They need to be stopped down further than that.

Before you disassemble the camera as suggested above, ck to see if the rear element has become loose as well. Generally, lens elements on TLRs do not loosen up on their own, so it may be that someone had the front element out to clean the shutter blades or something and did not get it screwed in tightly when putting it back in.

What you need to do is ck the focus w/ a loupe as suggested in the post above. You will need a tripod, a release cable to hold the shutter open on 'B' (on some models), a loupe or a 35mm slr lens to use as a loupe, and a piece of ground glass to lay on the film rails ground side facing the lens. Scotch tape stretched across there will do in a pinch, but the ground glass is much easier to work with and gives more accurate results.

After you have all that, put the camera on the tripod facing something like a tree or pole at least 100' -150' away w/ the camera set to infinity. If the image on the GG is not sharp, ck the image on top to see if it is sharp on the focus screen. My earlier model Rolleicords had an infinity stop screw on the focusing knob. You need to pop the cover off to see it. That allows you to adjust the taking lens infinity to the same image as is on the focus screen.

Also, ck to make sure that the focus screen is properly seated into position and that the focusing lens is not loose. Both it and the taking lens need to be in agreement. TLR's are simple box cameras w/ two lenses, and if you are at all handy, patient and thorough, you can usually figure things out and get them in the zone. The more complicated cameras like the Rolleiflex models are a PITA to work on because of their complicated controls for the film winding and aperture and speed settings.

Sarcophilus Harrisii 12-06-2018 08:12

Well Steve may have a point, the original comment was that the front element was loose, which I took literally—Ie glass loose in its mount. In which case the mount has to come out for investigation and possible disassembly.

On the other hand if the front mount is simply not fully threaded into the shutter then, do so, and check focus. The collet nut for the Va is easier to get to than the V model, adjustment of the infinity should be straightforward if needed. Note that you will need to dremel a slot in a suitable screwdriver blade in order to loosen and secure the brass collet nut which locks the focus knob onto the focus shaft.

albireo 12-06-2018 08:36

Apologies for the incorrect terminology - you're both correct, what I meant is that the front mount of the taking lens was not fully threaded in. I will perform the tests suggested by Steve and report back.

I am not sure I understand, however your point about a 'brass collet nut'. Could you kindly provide further pointers on what that is and how to access it?

Dan Daniel 12-06-2018 08:56

OK, I am confused. Before we send the guy down multiple rabbit holes, it'd be good to know what exactly he was dealing with being loose.

So OP, what exactly was loose? And did you remove it fully before screwing it back in? Can you loosen it up again? I don't remember the specifics on the Va Xenars, but some of these lenses can have the front retaining ring come off while the main body of the front group stays in the shutter block. Then the front element is loose. I think on Xenars the rear element is rolled into the brass mount but this could be variable.

Anyway, if the front retaining ring was loose and you don't recenter the front element properly to have it seat in the mount, things will be, well, not sharp.

Was anything sharp on the photos? In other words, was focus distance wrong, but parts of the image were sharp? If so, then you need to adjust the relation between the viewing lens and taking lens, and also adjust the infinity stop (luxury at this point, meaningless until you get the viewing and taking lens in agreement). If everything was soft, there is a problem in the lens elements, groups, and seating. No amount of messing with the focus system will get you sharp images.

The brass collet is underneath the plate on the focus knob itself. It allows you to set the infinity point on the focus travel based on a distant object or collimator. BUT, listen carefully, DO NOT go messing with this until you are certain where the problem is. If the lens elements are not seated properly, nothing you do with the focus knob will matter. If the viewing lens and taking lens are not aligned to show you proper focus on the screen, this will not matter.

There's an order to do various focus adjustments on a TLR to get it right. If you just jump into the middle, well, have you considered using your smartphone instead? And at this point, I am not convinced that there is ANY problem with the focus alignments and such; it could all be an improperly seated lens element or group.

The Xenar can be a great lens. A touch sharper than the Yashinon, a touch more open, in my experience. Sounds like you saw that in the first camera you had. Look, if this camera is also a turkey, send me a DM and we can talk about getting you a working, aligned, 12-exposure Va that will simply work from the moment you get it.

albireo 12-06-2018 09:10

Hi, I hope the following images are of help.

The loose front element I was referring to is the one indicated by the pen in the first image.
The second image shows that one can very easily, with no tools, fully take off the element.
Prior to shooting my test roll, I had indeed fully screwed in the element in the pictures below. Still, the pictures are not sharp.

Dan Daniel 12-06-2018 09:18

Your photo doesn't answer the first question I have- is it the complete front group that is loose, or it the front retaining ring for the front element?

Unscrew the whole thing and remove it. Do you get a metal retaining ring with glass still in front of the shutter blades? Or does it come out as a unit, maybe 3/4 inch tall, and the shutter blades are fully accessible?

albireo 12-06-2018 09:24

Hi again - thanks - I've attached a second photo above. What I get is the full unit out (it is indeed 3/4 inch tall). The shutter blades are fully accessible. The unit in my hand is solid, i.e. the glass element(s) do not move wrt the black metal retaining ring.

Dan Daniel 12-06-2018 09:50

Is the rear group seated? You can use a flat blade screwdriver in one of the notches to just gently try to rotate it- be careful of the glass, of course.

And the images you got- ANY sharp areas? Was focus off, of was the lens off. if that makes sense?

albireo 12-06-2018 11:26

Hi again

I've checked the rear group. It's firmly seated. I've gone ahead and firmly screwed the front group back in. Then, shutter in B, cable release and f/3.5, I've taped a yashicamat 124G focus screen on the back of the film chamber. Using an 8x loupe I've placed a far away (>300 feet ) pole in the middle of the frame, where the focusing screen horizontal split it is. I have tried to the best of my capability to achieve perfect focus and then noted down the position on the focusing knob.

I can confirm that perfect (based on my setup above) infinity was reached well before the infinity mark on the focusing knob. After a couple of tests I could reliably place the best infinity focus somewhere between 30 ft and 60 ft on the knob (close to 30).

To check the agreement with the viewing lens, I've then dropped my loupe onto the camera's own focusing screen (the one above the mirror). Again, I've tried to focus on the same far away object and noted down the mark on the focusing knob. This was in line with the 30ft noted above for the taking lens (a tiny bit closer to 30ft than before), suggesting perhaps the two lenses might be in sync, and that the whole assembly is focusing beyond infinite.

One point worth noting - I found it * much * more difficult to achieve perfect infinity focus using the camera's focusing screen into the viewing lens. The screen is very dim and does not have a split image in the centre. I am therefore wondering if the reason for the focusing inaccuracy I'm experiencing is due to my incapability of focusing with sufficient precision using the camera's focusing screen.

Dan Daniel 12-06-2018 13:04

So was there any good focus in the original images that have you worried? Is the lens not capable of making a sharp image, period? Or is the lens making a sharp image, it's just 20/40/375 feet closer/farther than you see on the focusing screen?

From what I hear you saying here, the viewing lens and taking lens are in relatively decent agreement. So this means that you should still be getting a sharp image, relatively close to where you focused on the screen. Yet your original post implied that the images were unsharp all over, with extremely unsharp corners. You'll need to figure this out- is the focus setting and agreement between the viewing and taking lenses off? This is a simple procedure to fix. Or is the taking lens junk? This is a different troubleshooting process.

The difference in focusing ease between the ground glass and the fresnel is typical. Get a brighter target.

albireo 12-08-2018 03:22

Hi again, thanks for all the advice. Based on your suggestions and on the decent agreement between the taking and viewing lens, I have to conclude at least a degree of operator error.

I am now shooting a further test roll in a more controlled scenario: camera on tripod, careful focusing and notes taken on object in focus. I will report back.

Dan Daniel 12-08-2018 16:23

Hope it works. The Xenar is a nice lens. Sounds like you have had enough delays getting going with a Rolleicord!

dxq.canada 12-09-2018 07:42

Doesn't Rick Oleson still sell focus screen upgrades for the Rollei ?

albireo 12-09-2018 11:10

Solved, admin please delete thanks

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