Resolved Suddenly getting noisy images

Discussion in 'STX and STXL' started by Peter Brack, Nov 29, 2018.

  1. Peter Brack

    Peter Brack Cyanogen Customer

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  2. Doug

    Doug Staff Member

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    Can you upload a dark frame FITS? Also one from before you noticed this problem?
     
  3. Peter Brack

    Peter Brack Cyanogen Customer

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  4. Peter Brack

    Peter Brack Cyanogen Customer

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  5. Peter Brack

    Peter Brack Cyanogen Customer

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  6. Colin Haig

    Colin Haig Staff Member

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    Peter - your NGC1097 will be gorgeous with some more signal ;-) Those darn filters sure block the photons.

    DarkFrame-0002D900 - whoa ! looks like a whole lot of radiation (possibly cosmic rays) hit that frame.
    Did you leave the spare plutonium in the observatory again? ;-)
    A few hits on the 120s as well.

    I'll let Doug weigh in on the noise.
     
  7. Peter Brack

    Peter Brack Cyanogen Customer

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    Haha yes they do Colin, need more signal, and stopped being radiated. I am now doubting any issue besides the fact I haven't stacked them yet and yes, just lack of signal. They were 900s subs so thought from previously they were less noisy than that.
    Anyway, will be good to know that there is no mechanical problem going on
     
  8. Doug

    Doug Staff Member

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    I don't see any obvious problem here. There isn't a good apples-to-apples comparison here (e.g. same exposure time), but with appropriate scaling it looks like the hot pixels are behaving consistently.

    Cosmic ray hits can be removed using appropriate SD Mask combining.
     
  9. Peter Brack

    Peter Brack Cyanogen Customer

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    Okay thanks for checking Doug . Maybe it’s the particular objects and also particular narrowband filters .
     

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