alpshiker

Hi Joe, Yes I know, there are easier ways. The reason I am considering that lens is that I can make use of a 90mm image circle. The Mamiya 645 lenses have 75mm. I also want the sharpness and contrast that ULD lenses produce on distant subjects, like mountains. The 210 f4 is probably a little too weak, although I only read other's comments. The AF 210 ULD would be fine, given a smaller image circle, but as you know, it has no manual aperture ring. The 200mm lens I use now is a Pentax 67. It is pretty sharp, but sometimes subject to flare in the centre. And talking LF lenses, I have tested my Fujinon A 240mm f9 on the device. It has reasonably good sharpness, and of course a huge image circle, but the distance of the back pupil towards the throat of the lens mount gives way to a lot of vignetting. That would be where the M7 lens could be far superior. Is is also a very compact and lightweight lens, and certainly flare resistant. Anyway, I'm just weighing the possibilities.

I have this seemingly excellent 210 N f8 that I wish to use on a shift-stitch device for landscape. This will require to alter the lens by removing the shutter blades or preventing that they can close, and to build a special adapter because the FF distance of the Mamiya 7 is some 3,5 mm shorter than the standard M645 mount. Or maybe machine the lens mount, or graft the lens elements in another lens like the plain 210mm for 645, if any of that is possible with a reasonable expense of work. But before anything is attempted that will destroy the lens as far as it's initial use is concerned, I wish I could check if the lens image circle will fit within the shift device, because this lens has a special design with small front and a large rear element. Is there any way to open the shutter by an electrical means so that it will stay open? I don't want to test before I know what I am doing. I noticed on the wiring diagram that there are two contacts for magnets, one is for the open position and another one for the closed position. This is probably for the B pose. But there are also other contacts for shutter control. Well, I suspect that what I am asking won't work if the lens is not coupled to the camera, but maybe there is a repairman trick to open the lens to see through it for inspection or bench calibration? And if all of that is impossible anyway, it is always interesting to talk about it.

You have probably found the culprit by now since this post dates! But I remember having had some issues when I began using the GS1, that was a long time ago. The GS1 camera feels a little fiddly, but it is stronger than you would think and I never had to send it out for a repair in the years I used it. But one thing that can happen when mounting the back, if one is not careful, and especially when switching backs in a hurry, is that one of the two bottom (or top?) hooks can stay out, while the other is hooked. This can go unnoticed until you forward the film with the camera. Then the small dented wheels are not synchronized and you get problems such as you describe. If this is what happened when you got the bad behaviour, you would have noticed that it was difficult to detach the back. I never used the grip but only the rotating handle, and I don't have the camera any more so I cannot provide a step by step, but there should be a way to fool the camera to check if the dented wheel is turning, maybe by mounting the back and leaving it open if that is possible. I think there needs to by a film in to drive the mechanism. Also, if you don't have a manual with the camera, find one and read how to load the film properly, for there is a special manipulation with the double exposure lever while advancing the film, if I remember right. Bottom line, if it doesn't work, don't throw the baby out but take time to go through all the procedures until you master it. Be gentle with the camera and it should serve you well. PG lenses are great optics.

<p>On the GS-1, when not careful or when working in a hurry it is actually possible to clamp the back with one of the hooks misplaced. Happened to me once and all the shots were fogged. But you would have seen it when you took the back off, for it is harder to unhook. The camera is lightweight for a 6x7 format. If not exactly built like a tank, it's nevertheless a robust camera. </p>

<p>I have used a Bronica GS-1. It is a nice camera. Much lighter than RB/RZ, it can be handheld, there is even a rapid grip for it, and comes with some very sharp and contrasted lenses which are of a late computer design. They are no fast lenses however. The whole operation of loading films and back swapping is a bit tricky at first, but once the method is acquired it's not a problem. At the time, new lenses were very expensive and I had a Pentax 67 opportunity. I kept the GS-1 for the studio, and used the Pentax outside.</p>

<p>Not something I would tackle, but Steve Mallett provides some practical does and don't from his experience on <a href="http://osdir.com/ml/recreation.photography.equipment.rollei/2005-07/msg00178.html">this page</a> (unsigned).<br /> My single experience at taking a lens apart is almost 40 years old. It was a nice Nikkor 50mm 1.2 that an australian friend used for underwater photography (some might remember the price tag, a month of my wage). It had fungus, so I offered to clean it. All went well, elements clean, when the last lens to get in slipped from my hands and crashed onto the concrete floor… Reminds me that I must bring him a new one when I get to heaven.</p>

<p>The seller was I think, unaware of the problem. He politely apologized and offered a full refund. All is well.</p>

<p>Interesting outcome with the Dagor! I suspect that the balsam has crystallized and heating the lens element reversed the process? Modern lenses use different chemical compounds, some are two components, others harden with UV light. It's not certain that they would melt with heat. But certainly worth experimenting if the lens is dead anyway.</p>

<p>Thanks for this advice Charles. If it were not for some worrisome posts I have now found elsewhere, I would probably try. Others have done that to find out that the haze stood between the glued elements. It looks as though this is a programmed genetic illness of the 1.9N, or at least of some batches of it. The older C has another design. I should probably send it back. I am now a little worried for the handful top mamiya lenses I have in my bag. Is balsam fogging known to occurr on other N lenses?</p>

<p>Hi,<br> I just purchased a mint looking N lens from Japan on the bay. To much of my surprise though, the rear element has haze, in such extent that it is unusable. I am assuming that this is due to balsam opacity, or perhaps separation in the rear element. Having it fixed would probably cost more than the $300 I spent so far, if such was available. I will certainly obtain from the seller that he takes it back, for he mentioned no problem with glass. The lens looks so good however—it is like new—, that it's heart breaking to dump it. Has anyone had success in removing haze from a 1.9 N? Are rear lens cells still available?</p> <div></div>