Switch to English Language Passer en langue française Omschakelen naar Nederlandse Taal Wechseln Sie zu deutschen Sprache Passa alla lingua italiana
Members: 69,970   Posts: 1,523,521   Online: 847
      
Page 2 of 2 FirstFirst 12
Results 11 to 15 of 15
  1. #11
    Fixcinater's Avatar
    Join Date
    Dec 2008
    Location
    San Diego, CA, USA
    Shooter
    127 Format
    Posts
    857
    Images
    17
    I have recently acquired a Sonnar 150mm for Hasselblad, which looks like it was dunked in the ocean, so perfect for doing some real-world testing. Lots of cleaning marks on the front element, and toothpaste didn't do anything to the ruined coating. I then tried aluminum polish which cleaned it up. I haven't done testing yet but it looks markedly better and much more reflective than it once was.

  2. #12
    Mark Feldstein's Avatar
    Join Date
    Jan 2006
    Location
    Monterey, CA / BiCoastal NY
    Shooter
    Multi Format
    Posts
    163
    Possible? I don't know. If it requires recoating I think you'd be better off avoiding situations that produce flare and get a good lens shade. OTOH, if it residual cleaning material and it needs some sort of disassembly, recleaning and polishing, you could try these guys at Midwest Camera. They give online estimates that are pretty reasonable.
    http://www.midwestcamera.com/classic.html

    Also, since you're in NYC, NY Lens and Repro merged with Calumet. NYLR always did great repair work and since they're in with Calumet now, take a ride down there and ask them to take a look. Calumet Photographic at 22 W 22 Street, NYC. It might be worth having them check it out.
    _________________________________
    Without guys like John Coltrane, Count Basie and Duke Ellington, life....would be meaningless.

  3. #13
    Newt_on_Swings's Avatar
    Join Date
    Mar 2011
    Location
    NYC
    Shooter
    Multi Format
    Posts
    1,787
    I went at a front element the other day with toothpaste (the plain white type ) together with hydrogen peroxide and methanol to prevent it from drying out. Went at it for half an hour and it didn't do squat. I'll have to try some other polish.

  4. #14
    Ian Grant's Avatar
    Join Date
    Aug 2004
    Location
    West Midlands, UK, and Turkey
    Shooter
    Multi Format
    Posts
    16,216
    Images
    148
    Quote Originally Posted by Gerald C Koch View Post
    Fungus damage can be removed by using cerium oxide mixed with water as a polish. People make telescope mirrors all the time and the final step is polishing. Check the web for suppliers. As mentioned above the coating will have to be re-applied. When I was in graduate school I had to polish sodium chloride optical windows all the time. Only difference was using ethyl alcohol instead of water. (Sodium chloride transmits infra-red light while glass will not.)
    I bought some Cerium Oxide last year when i bought new stocks of polishing grits. I had to make some Rollei focus screens for a Microcord & Rolleicord III and decided to give the Cerium Oxide a try after the #600 grit I normally use - the reults were the glss began to polish smooth losing the ground grain. The Lapidiary supplier I use had told me they mainly sold Cerium Oxide to telescope makers.

    Ian

  5. #15

    Join Date
    Sep 2011
    Location
    Adirondacks
    Shooter
    Multi Format
    Posts
    3,325
    All you guys using abrasives like cerium are taking the glasses out of the cell and using pitch blocks to polish them, right? Because if you don't, you'll spoil the figure of the surface and have a nice shiny paperweight.
    There's a reason it's expensive to get lenses repolished, it takes skill and special tooling made specifically for each job.

Page 2 of 2 FirstFirst 12


 

APUG PARTNERS EQUALLY FUNDING OUR COMMUNITY:



Contact Us  |  Support Us!  |  Advertise  |  Site Terms  |  Archive  —   Search  |  Mobile Device Access  |  RSS  |  Facebook  |  Linkedin