Ground glass ghosting

Discussion in 'Large Format Cameras and Accessories' started by Snowball Earth, Mar 19, 2017.

  1. Snowball Earth

    Snowball Earth Subscriber

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    Anyone have any idea why I have a separate ghost image on my Super D? It's semi transparent and just above the focused object. The lens is an Aero Ektar and the mirror is a brand new first surface replacement.
    No fresnel, just the original glass.
    Any advice is appreciated.
    Dwayne
     
  2. Ian Grant

    Ian Grant Subscriber

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    Probably someone has replaced the reflex mirror it needs to be a front/first surface mirror as you indicate. As it is then maybe it's the wrong way around. That's the only way you can get that ghost image.

    Ian
     
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    Snowball Earth

    Snowball Earth Subscriber

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    Hmmmm, not sure what's going on then, I just bought it from a company that specializes in this. The other side is kind of blue, impossible to mix up.
    D
     
  4. Ian Grant

    Ian Grant Subscriber

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    A front surface mirror is normally plain clear glass on the rear, there's no need for a coating as no light passes through the front surface, usually on older cameras they are placed on velvet or something similar. The coating is usually aluminium these days rather than silver. When I had a new mirror made for a Ruby Reflex it came with a coloured protective very thin plastic film on the front surface maybe that's the blue you see. It's there to protect the mirror before it's fitted and has to be removed, so maybe there is a mix up.

    Ian.
     
    Last edited: Mar 19, 2017
  5. OP
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    Snowball Earth

    Snowball Earth Subscriber

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    That may explain it! If that is the problem then I'm in for a fair bit of work tearing it all down again and recalibrating the back and GG. I guess the back side of the mirror looked so nice it threw me off the scent......
    Thanks
    D
     
  6. neilt3

    neilt3 Member

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    The last replacement mirror I bought was for a Mamiya C3 .
    On the side with the mirror there was a piece of protective blue plastic/polythene (?) to protect the mirror from scratches whilst in transit and until it was installed .

    The rear of the mirror was just uncovered plain glass , but the mirrored side was clear to see .

    Maybe it's been installed back to front ?
    If the mirror is removed again , see if the blue coating is the protective layer on it , it will peel off very easy .
    If you installed it yourself , was there anything on the surface you believe to be the mirrored face to protect it ?
     
  7. Ian Grant

    Ian Grant Subscriber

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    My mirror was made for me by Vacuum Coatings Ltd in London (UK) it came with a note that the front surface had a silicone coating on top of the aAluniminim vacuum coating and a plastic film for protection I think it was blue polythene. You get a similar protective film on some plastics and & brass sheets although usually a different colour.

    Ian
     
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    Snowball Earth

    Snowball Earth Subscriber

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    I did indeed have the mirror installed upside down. So thanks for the advice. Lesson learned!
    Dwayne
     
  9. Ian Grant

    Ian Grant Subscriber

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    Glad to be of help, that's what APUG is for :D No you can have fun with your Aero Ektar.

    Ian