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Thread: Has there been significant improvement in noise control over the past 4 years?

  1. #21
    Senior Member rain5533's Avatar
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    Quote Originally Posted by sin77
    So tokgong
    Ha ha ha.., tokgong

    Laughing until cant stop your comments

  2. #22
    Senior Member rain5533's Avatar
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    Quote Originally Posted by ArchRival
    Thanks for the input guys.

    Went ahead and got a 600D. Here is a noise test comparison between the 400D and 600D at ISO 1600, 4 minutes. Both shots taken with the body cover on, 100% crop. The raw files are converted to 16-bit tiff using Canon's Digital Photo Professional, then changed to jpg for uploading. There is this noise reduction thing for high iso in the 600D. Don't know how that works, so turned it off. Both images were taken immediately after the cameras were switched on.

    600D

    400D

    I'm attempting astrophotography, hence the need for high ISOs and long exposure times. The filter used is a broadband UHC/LPR. It filters out sodium and mercury emission spectra to reduce sky glow, but also restricts light transmission quite severely. The final product is an image where stars are captured, but the downside is lots of image noise.

    Anyway this is a quick test. The bright star in the middle is Gamma Ursae Majoris in the Big Dipper. ISO 1600, 4 minutes. Optical system is of focal length 900mm, F/6.3. Not many stars seen here because the field of view is quite narrow. Also, there seems to be some light leak at lower left corner from the led indicator.
    The sky is noise or stars?

  3. #23

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    Quote Originally Posted by ArchRival
    Thanks for the input guys.

    Went ahead and got a 600D. Here is a noise test comparison between the 400D and 600D at ISO 1600, 4 minutes. Both shots taken with the body cover on, 100% crop. The raw files are converted to 16-bit tiff using Canon's Digital Photo Professional, then changed to jpg for uploading. There is this noise reduction thing for high iso in the 600D. Don't know how that works, so turned it off. Both images were taken immediately after the cameras were switched on.

    600D

    400D

    I'm attempting astrophotography, hence the need for high ISOs and long exposure times. The filter used is a broadband UHC/LPR. It filters out sodium and mercury emission spectra to reduce sky glow, but also restricts light transmission quite severely. The final product is an image where stars are captured, but the downside is lots of image noise.

    Anyway this is a quick test. The bright star in the middle is Gamma Ursae Majoris in the Big Dipper. ISO 1600, 4 minutes. Optical system is of focal length 900mm, F/6.3. Not many stars seen here because the field of view is quite narrow. Also, there seems to be some light leak at lower left corner from the led indicator.
    You are using a special head to follow stars movement?

    Just curious, will there still be any sky glow if there is no light pollution?
    Coolthought - 冷静思考 - クールだ http://xaa.xanga.com/0aba0666d143253.../t35917343.gif

  4. #24

    Default Re: Has there been significant improvement in noise control over the past 4 years?

    Quote Originally Posted by rain5533 View Post
    The sky is noise or stars?
    Those are stars.

  5. #25

    Default Re: Has there been significant improvement in noise control over the past 4 years?

    Quote Originally Posted by coolthought View Post
    You are using a special head to follow stars movement?

    Just curious, will there still be any sky glow if there is no light pollution?
    There will still be glow from neutral oxygen.

  6. #26

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    Quote Originally Posted by coolthought

    You are using a special head to follow stars movement?

    Just curious, will there still be any sky glow if there is no light pollution?
    No need special head to follow star movement if exposure is short (I think less than 1 minute). My typical exposure times: f/2.8: 15 sec ISO 6400, 30-60 sec ISO 3200. f/1.4: 15 sec or less, ISO 1600-3200. Sky glow (in my experience) usually comes from light pollution. Right now, I shoot stars at wider angles than the ones here, though. This one here: ISO 6400, 15 sec, f/2.8. 1 x 3 pano.


    Winter Night
    Last edited by nathaniel; 18th May 2012 at 03:33 PM.

  7. #27

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    Quote Originally Posted by ArchRival

    There will still be glow from neutral oxygen.
    Quote Originally Posted by nathaniel

    No need special head to follow star movement if exposure is short (I think less than 1 minute). My typical exposure times: f/2.8: 15 sec ISO 6400, 30-60 sec ISO 3200. f/1.4: 15 sec or less, ISO 1600-3200. Sky glow (in my experience) usually comes from light pollution. Right now, I shoot stars at wider angles than the ones here, though. This one here: ISO 6400, 15 sec, f/2.8. 1 x 3 pano.

    Winter Night
    Thanks guys for sharing.
    Coolthought - 冷静思考 - クールだ http://xaa.xanga.com/0aba0666d143253.../t35917343.gif

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