Archived posting to the Leica Users Group, 1998/11/09
[Author Prev] [Author Next] [Thread Prev] [Thread Next] [Author Index] [Topic Index] [Home] [Search]The vast majority of older Leica lenses seem to exhibit hazing, clouding or mottling of some sort. The early (collapsing and fixed) Summicrons also are many times found with defects to the front element coating. Other problems such as fungus and cement separation are possible also, as is oil droplets from an improper lube of the diaphragm. As you surmise, contrast reduction (and flare) are the chief results, but certain defects can cause sharpness loss also. Sometimes the elements can be cleaned, but it does cost money. Etching from fungus, and scratches from wiping, can not be cleaned off. Mr Van Stelten of Focal Point (mentioned here before) has facilities for cleaning as well as re-coating lenses, but the latter process is quite expensive and for a common lens such as the DR Summicron, probably not worthwhile. It all depends upon your paying price vs. actual worth. If the lens is not returnable, you rather have two choices: use the lens as is, or send it for a repair estimate. I would certainly run a film through it before making the decision. Regards, Nigel On Mon, 09 Nov 1998 15:13:46 +0100 "Martin V. Howard" <marho@ida.liu.se> writes: >I attended an auction this weekend and bought a 50mm NF-Summicron at a >very reasonable price. I had examined the item prior to the bidding, >but only after buying it did I notice, upon shining a flashlight >through >the lens, that there are markings on the internal lens elements. > >The marks are faint, light/white "scratches", fairly numerous, that >are >shaped as concentric circles. They appear to be on one of the >surfaces >of the element closes to the rear element and seem perfectly circular. >If you think of photographs of night skys, with startrails, that's >pretty close to what it looks like. > >I don't actually know if they are scratches, hense the quotation >marks. > >Does anyone know what these are? Can it be removed? I suspect that >they will affect contrast and sharpness. They are quite faint (only >detectable when shining a flashlight through the lens), but they are >also quite numerous. Does anyone know for sure how these will affect >the image quality? > > >M. > >-- >Martin V. Howard, Application Systems Laboratory, | >Dept. of Comp. & Info. Sci., Linkoping University, | Just "DOHH" >it! >SE-581 83 Linkoping, Sweden. Tel +46 13 282 421, >+----------------+ >Fax +46 13 142 231; marho@ida.liu.se; www.ida.liu.se/~marho > ___________________________________________________________________ You don't need to buy Internet access to use free Internet e-mail. Get completely free e-mail from Juno at http://www.juno.com/getjuno.html or call Juno at (800) 654-JUNO [654-5866]