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  • #31
    Re: Lens Fungus

    Originally posted by Naughty Nigel View Post
    LED's of whatever colour usually provide a very narrow and specific bandwidth of light which I doubt would be of much value in killing fungus.

    The wavelength of UV LED's is usually close to visible light, and is intended for use with UV reactive pigments used in security marking and crack detection systems such as Ardrox.
    Just to clarify any confusion, I was talking about 'white' LEDs, as commonly used to replace filament bulbs. IIRC, these work by either emitting in the UV, which stimulates emission from 3 colour phosphors to simulate the visible spectrum, or by emitting at short wavelength visible and using a complementary colour phosphor for the other part of the spectrum. The latter type do not emit in the UV.

    Mark

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    • #32
      Re: Lens Fungus

      On a tangent here, and probably worth of an entry at Pseuds Corner in the 'Eye, just had a thought, the light-bulb moment! The fungus could add a creamy effect to the images. And if the fungus is active and growing, no two images will be the same. Pack away the UV lamps and the formaldehyde!
      Steve

      on flickr

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      • #33
        Re: Lens Fungus

        Originally posted by Phill D View Post
        I've just had an older 4/3s 70-300 lens cleaned of some internal fungus by Luton Camera Repairs and they sorted it out very well at a very reasonable cost.
        Just lost 2 pairs of binoculars to fungus, so good to know I've got somewhere 31 miles away who could sort out some of my older lenses with sentimental value.

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        • #34
          Re: Lens Fungus

          Originally posted by Phill D View Post
          It's the 4/3s 70-300mm lens. They cleaned it a treat though for 50 quid. Couldn't see any evidence after. Unfortunately it's gone back for another issue that became apparent afterwards so I've not been able to check out it's performance yet but I've no reason to believe it wont be back to normal from the way it looked.
          Regards,
          Mark

          ------------------------------
          http://www.microcontrast.com
          Too much Oly gear.
          Panasonic GM5, 12-32, 12-35, 15, 35-100, Laowa 7.5.
          Assorted legacy lenses, plus a Fuji X70 & a Sony A7S.

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          • #35
            Re: Lens Fungus

            Gosh this is an old thread resurrection. Yes Mark it came back fine as far as I know. Didn't do the light test but will dig it out and try it for you later.
            http://www.flickr.com/photos/flip_photo_flickr/

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            • #36
              Re: Lens Fungus

              Originally posted by Phill D View Post
              Gosh this is an old thread resurrection. Yes Mark it came back fine as far as I know. Didn't do the light test but will dig it out and try it for you later.
              You might not like to know!

              I hadn't spotted it was quite that old a conversation.

              I would be interested, though, and it would influence whether I ever got it done for anything else in the future. The Elmar had probably sat around with the fungus for years and it wouldn't be a surprise if it could have been cleaned without leaving a trace earlier. It was nice to get it done for nostalgia reasons anyway, and it does still take very decent pictures!
              Regards,
              Mark

              ------------------------------
              http://www.microcontrast.com
              Too much Oly gear.
              Panasonic GM5, 12-32, 12-35, 15, 35-100, Laowa 7.5.
              Assorted legacy lenses, plus a Fuji X70 & a Sony A7S.

              Comment


              • #37
                Re: Lens Fungus

                I've never understood what nutrition a fungus can get from glass!

                Jim

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                • #38
                  Re: Lens Fungus

                  I think the fungus eats the coatings rather than the glass. That may explain why Mark sees horrible-looking stuff in his old Elmar - the fungus may be gone but the half-digested coatings are still there. But if it takes good photos, why worry?

                  John

                  Comment


                  • #39
                    Re: Lens Fungus

                    In my house anything leather is a potential disaster area and seems to attract mould. I have a pair of Zeiss Jenoptem binoculars in a beautiful leather case which were stored in a drawer. Unfortunately I didn't notice that the case had become covered with green mould and it has affected the prisms inside the binoculars. I now have a pair of binoculars in excellent exterior condition but which are totally useless. I now worry when I see people boasting about their lovely leather camera cases and straps. I will take the synthetic option every time.

                    Ron

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                    • #40
                      Re: Lens Fungus

                      Originally posted by Naughty Nigel View Post
                      This is an interesting point. LED's emit a very narrow bandwidth of light, (it is an electrochemical reaction after all). I can imagine that LED's emitting near infra-red light could do a lot of damage before anyone realises.

                      White LED's try to cover the entire visible spectrum by using multiple chips, but most cheaper devices emit very little in the infra-red or near infra-red spectrum; hence their horrible colour rendition. Many cheaper devices also tend to emit of a lot of light in the green spectrum as the eye is most sensitive in this region.

                      These days white LEDS generally have phosphors to widen the wavelength range. The LED it's self will excite the phosphor. But as you say very little IR from them especially compared to tungsten lights or the sun...
                      Mike
                      Compulsive photographic Dabbler.
                      Flickr

                      Comment


                      • #41
                        Re: Lens Fungus


                        It's actually more useful to inspect an out of focus image of that bright light. Muck in the lens system can be seen in the Bokeh.
                        Mike
                        Compulsive photographic Dabbler.
                        Flickr

                        Comment


                        • #42
                          Re: Lens Fungus

                          OK Mark so got the lens and used the bright LED and yes there does seem to be a few specks of dust in the lens but no fungus so it looks like Luton did do a pretty good job on it. I was surprised to see the dust although it was over three years ago since it was cleaned so maybe that's too be expected? I looked at my much newer 12-100 and 40-150 lenses and they looked pretty much dust free. Looking closely at your lenses is an interesting thing to do. I was surprised to see that the old 70-300 was a very open lens design so it's not surprising that dust can get in as it's zoomed. The other lenses were a totally sealed design. I suppose as they are waterproof that shouldn't have surprised me but to be honest I'd never thought about it before. Another thing was the aperture that was stopped down on both the newer lenses but wide open on the older one. Is this a function of the change from a 4/3s lens to a micro 4/3s lens? It certainly made inspecting the newer lenses more difficult. Now to go and dig out my adapter to try out the old lens on my EM1 mk2 just to see how it performs. Never tried it on the mk2. I doubt the small amount of dust will be an issue.
                          http://www.flickr.com/photos/flip_photo_flickr/

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                          • #43
                            Regards,
                            Mark

                            ------------------------------
                            http://www.microcontrast.com
                            Too much Oly gear.
                            Panasonic GM5, 12-32, 12-35, 15, 35-100, Laowa 7.5.
                            Assorted legacy lenses, plus a Fuji X70 & a Sony A7S.

                            Comment

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