Olympus-OM
[Top] [All Lists]

Re: [OM] 8mm OM analogue 2.8 OM fisheye users please contact me off-list

Subject: Re: [OM] 8mm OM analogue 2.8 OM fisheye users please contact me off-list
From: SwissPace <ian@xxxxxxxxxxxxxxxx>
Date: Wed, 25 Jun 2014 18:04:34 +0200
If you search the posts way back for fungal fisheye you will find that I did just that. My chemicals may be wrong but IIRC I removed the rear element (easy) and tried cleaning with ponds cream as recommended by john, I then soaked in acetone to clean but when I returned the doublet had split so I then searched for some glue. The supplier I found here asked why I wanted the cement and then offered to glue/cement it for me for a minimal cost (around 20 dollars plus postage ) so I decided that was best option as the cement would have cost more and he could true it. Apparantly you make a plasticine holder if you want to try truing it yourself. BTW when it split I chipped the edge which I painted black but they removed this when they recemented the doublet and I left it like that.

It never really became perfect but it was improved, however as has been mentioned (by chuck?) you can get away with a lot of dirt on a lens.

here is the rear element after a first go with ponds (hope I remembered that right) so its was worse than this

http://thattimeoflife.smugmug.com/My-MAIN-gallery/Misc/i-M65SCHq/A

and here is a picture taken with it in the previous state - admittedly on the E1 so not using the full circle of the lens

http://thattimeoflife.smugmug.com/My-MAIN-gallery/Misc/i-SWSsSNC/A




Sawyer, Edward <mailto:Ed.Sawyer@xxxxxxx>
25 June 2014 17:19
The only real possible solution for this is extract the inner element pair
(presuming it's a cemented pair), de-cement them, and re-cement them with
new cement. Edmund Optics carries the tools and supplies you would need
for this. It's not a trivial piece of work, and would only be worth trying
on an otherwise useless lens.

The above assumes the fogging is in the cementing, which is probable.
However, some types of glass can chemically change with time, effectively
dissipating some of their materials to the surface of the glass, resulting
in permanent haze. Not sure if the OM fisheyes are of that nature or if
it's cemented elements that are to blame.

The mamiya RZ67 75mm shift/SB lenses have a common ailment like this too,
in a rear cemented pair.

-Ed


On 6/24/14 6:16 AM, "olympus-request@xxxxxxxxxxxxxxxxx"

--
_________________________________________________________________
Options: http://lists.thomasclausen.net/mailman/listinfo/olympus
Archives: http://lists.thomasclausen.net/mailman/private/olympus/
Themed Olympus Photo Exhibition: http://www.tope.nl/

<Prev in Thread] Current Thread [Next in Thread>
Sponsored by Tako
Impressum | Datenschutz