Resolved STF3800C using CLA Camera lens adaptor

Discussion in 'STF Series CCD Cameras' started by Robert Shartrand, Dec 17, 2018.

  1. Robert Shartrand

    Robert Shartrand Standard User

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    Has anyone tried using the STF3800C with the CLA STF camera lens adaptor sold by Diffraction limited?
    If so, I'd be using a Nikon 180mm lens at f4. But I need to know about the image quality. Grain, resolution etc.
    The 5.4 pixels are very oversampled with my telescopes.

    Thanks,
    Bob
     
  2. Colin Haig

    Colin Haig Staff Member

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    What exact Nikon lens is it you are using?
    And do you mean STF8300 ?
     
  3. Robert Shartrand

    Robert Shartrand Standard User

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    Hi Colin, The camera is a STF8300Color version and the lens is a Nikon 180mm f2.8 stopped down to f4.
    The lens works very well with my ST8XME mono or with LRGB filters all binned 1x1.
    Thanks for your reply,
    Bob
     
  4. Colin Haig

    Colin Haig Staff Member

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    That lens has a great reputation - although there were a few versions of it, and some are sharper than others.
    The good news is that the resolution on an 8300 sensor is about 6 arcseconds per pixel; so if you have moderate seeing conditions where you are, it should perform nicely.
    As a colour camera, it may be a bit under-sampled if you have excellent seeing. I use an 8300 color sensor on my 600mm astrograph, and I wish I had a slightly shorter focal length.
    As far as "grain" goes, an STF-8300 can be cooled beyond 35C below ambient, and that gets rid of a lot of the noise from that sensor.
    The mono sensor versions are very popular, with filter wheels. The C versions are getting to be a bit rare.
     
  5. Robert Shartrand

    Robert Shartrand Standard User

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    Thanks Colin,
    Others have told me that resolution and sensitivity suffers when using OSC cameras for astrophotos. I have to tell you though that with my ST10xme with 6.8 size pixels is amazing with that lens.
    I wish I knew where I could get some subs done with the STF8300C so I could process them myself.
    Bob
     
  6. Colin Haig

    Colin Haig Staff Member

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    Well, the facts are that the effective resolution of a OSC is LOWER - due to the fact that a single "finished" colour pixel in the final image is made up of four real pixels - R G G B in a Bayer matrix. So a mono camera 8300 camera will have double the number in each axis that can respond to incoming photons for all colours. Thats why a mono 8300 with filter wheel may make more sense for some people.
     
  7. Doug

    Doug Staff Member

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    Rule of thumb - after conversion the Bayer color sensor’s resolution is about 30% less than monochrome.
     
  8. Robert Shartrand

    Robert Shartrand Standard User

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    Thank you Doug and Colin.
    Bob
     

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