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Peter_nap
Tinkerer
Username: Peter_nap
Post Number: 3
Registered: 04-2012
Rating: N/A
Votes: 0 (Vote!) | | Posted on Thursday, May 03, 2012 - 12:51 pm: | 
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My first post here was about repairing a Nikkor 28mm lens that the diaphragm was stuck on. I was able to fix it thanks to all.
My question is should these old manual lenses be stored objective lens down to keep oil from the vanes?
Thanks again! |
Mareklew
Tinkerer
Username: Mareklew
Post Number: 270
Registered: 03-2010
Rating: N/A
Votes: 0 (Vote!) | | Posted on Friday, May 04, 2012 - 03:57 am: |
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Generally long time storage, if any preference was to be made, should be standing upright, so that any lubricants from the lens barrel, the helicoid, etc., shall they migrate, would migrate along the barrel and not onto the lens elements.
Whether mount side up or front element side up is a harder thing, but I'd say for prime lenses, especially large aperture ones, the preferred position would be front-element down. The reason would be, that the front element is usually easier to access for cleaning, should any lubricant migrate onto it. Also, the lens helicoid is most often open towards front, so migrating lubricant has a preferred way out of the lens.
Exception: (ultra)-wide-angle lenses. Lenses that have front element much larger than the entry pupil, these have usually front element that's hard to remove and is quite critical in the assembly.
Now, that all is like: IF there was any difference I could think of, these would come to mind. I store my old lenses upright to save space and which way do I put them depends on which way are they more stable. Most important is to put lens caps on both ends...
Marek |
Brianshaw
Tinkerer
Username: Brianshaw
Post Number: 128
Registered: 07-2006
Rating: N/A
Votes: 0 (Vote!) | | Posted on Friday, May 04, 2012 - 08:33 am: |
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I've never cared about the position a lens is stored in as much as the conditions: dry and constant temperature. If the grease is migrating than the grease has gone bad and the lens is in need of an overhaul.
More often than not, though, I store 35 and MF lenses with the mount up... but that is because that's how they it in the camera bag best. LF lenses are generally stored on their side for a very similar reason. |
Peter_nap
Tinkerer
Username: Peter_nap
Post Number: 4
Registered: 04-2012
Rating: N/A
Votes: 0 (Vote!) | | Posted on Friday, May 04, 2012 - 09:50 am: |
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Thanks Guys!
I never gave it much thought until I started buying a lot of old lenses and realized just how many had stuck apertures.
I have nearly a dozen now to take apart and clean. |
Mareklew
Tinkerer
Username: Mareklew
Post Number: 271
Registered: 03-2010
Rating: N/A
Votes: 0 (Vote!) | | Posted on Tuesday, May 08, 2012 - 01:09 pm: |
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Brian,
"If the grease is migrating than the grease has gone bad and the lens is in need of an overhaul."
This is not entirely right.
Grease is oil suspended in an "oil carrier". While separation is a sign of aging, some oil is going to get released way before the grease ages beyond its desired properties. Especially the older lubricants, often of natural origin, are prone to this.
Of course, an overhaul is preferred solution, especially that very old grease will stick badly.
Marek |
Brianshaw
Tinkerer
Username: Brianshaw
Post Number: 129
Registered: 07-2006
Rating: N/A
Votes: 0 (Vote!) | | Posted on Tuesday, May 08, 2012 - 03:04 pm: |
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Yes, of course. I was using common terms and didn't think it necessary to get into that level of details. It's like talking about a vinagrette salad dressing, which most people understand, versus calling the same an "emulsion of oil and vinegar with some flavorants being held in suspension"... which it is but not everyone understands.
The bottom line is that when the grease separates to the point where it contaminates other parts of a lens... it has out-lived its useful life. |
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