Site Sponsors
Results 1 to 9 of 9

Thread: Seeing Stars with the XP1... this can't be real.

  1. #1
    Senior Member Jim Radcliffe's Avatar
    Join Date
    Mar 2009
    Location
    Texas
    Posts
    627
    Post Thanks / Like
    Images
    8

    Seeing Stars with the XP1... this can't be real.

    Using the X-Pro1 with the 500mm Minolta Mirror Lens & the 135mm
    I bought the 500mm Minolta lens a year or so ago to use on my Micro Four Thirds cameras but have not really used it all that much. Tonight (August 1, 2012) there was a clear sky and a beautiful full moon and despite it being way past my bedtime I took this shot.



    Here is the Mystery Shot taken with the Minolta 135mm

    I can't explain what you will see in the shot below. It was taken with another Minolta legacy lens, the MC Tele Rokkor X PF 135mm. This is very strange. Are those really stars? Of course not.. but I have no idea why this shot (and all other shots with this lens) came out with what appears to be stars in the photo. Very weird.... They appeared when I was adjusting clarity in Lightroom 4. The more clarity, the more "stars" appeared. I know they can't be real stars but what are they? I did not add them.. they just appeared as I pumped up the clarity in Lightroom.



    If you know what is causing this.. please let me know. No way those are real stars.
    Last edited by Jim Radcliffe; 1st August 2012 at 23:33.
    Jim Radcliffe
    www.boxedlight.com
    Likes 1 Member(s) liked this post

  2. #2
    Senior Member
    Join Date
    Aug 2011
    Location
    San Francisco
    Posts
    889
    Post Thanks / Like

    Re: Seeing Stars with the XP1... this can't be real.

    At night time you're pretty much recording the intensity of light, especially pointed up at the sky. I see no reason why they are not stars. Perhaps try a long exposure next time to see if you see streaks on a tripod, that will probably confirm them as stars!
    ___________________
    Po-Ming Chu
    POPHOTO

  3. #3
    Senior Member Jim Radcliffe's Avatar
    Join Date
    Mar 2009
    Location
    Texas
    Posts
    627
    Post Thanks / Like
    Images
    8

    Re: Seeing Stars with the XP1... this can't be real.

    Quote Originally Posted by pophoto View Post
    At night time you're pretty much recording the intensity of light, especially pointed up at the sky. I see no reason why they are not stars. Perhaps try a long exposure next time to see if you see streaks on a tripod, that will probably confirm them as stars!
    No stars were visible to my eye due to the bright, full moon. Shutter speeds were very fast, not long enough for any faint stars to make their presence known and as you can see from the photo it almost looks like a star field.. not just a single bright star.

    I am beginning to think it has something to do with the 135mm lens as the 500mm did not exhibit this at all. Dust? or something else? Who knows.. I ams sure this is not a case of hot pixels.
    Jim Radcliffe
    www.boxedlight.com

  4. #4
    Senior Member aleksanderpolo's Avatar
    Join Date
    Mar 2010
    Posts
    263
    Post Thanks / Like

    Re: Seeing Stars with the XP1... this can't be real.

    If the exposure of the first and second shot are similar, dust illuminated by the moonlight? What is the aperture used for the second shot?

  5. #5
    Super Duper
    Senior Member
    Shashin's Avatar
    Join Date
    May 2011
    Location
    Florida, USA
    Posts
    4,497
    Post Thanks / Like
    Images
    141

    Re: Seeing Stars with the XP1... this can't be real.

    Sensor artifacts like noise. To have also really pumped the contrast on the moon image which is making it easier to get these artifacts. You are near full moon which makes the moon a very low contrast target.

  6. #6
    Senior Member
    Join Date
    Aug 2011
    Location
    San Francisco
    Posts
    889
    Post Thanks / Like

    Re: Seeing Stars with the XP1... this can't be real.

    Quote Originally Posted by Jim Radcliffe View Post
    No stars were visible to my eye due to the bright, full moon. Shutter speeds were very fast, not long enough for any faint stars to make their presence known and as you can see from the photo it almost looks like a star field.. not just a single bright star.

    I am beginning to think it has something to do with the 135mm lens as the 500mm did not exhibit this at all. Dust? or something else? Who knows.. I ams sure this is not a case of hot pixels.
    Well I can't rule out dust completely, but if your camera meters a big bright ball like the moon, you will still get a quick shutter for exposure, and lightly picking up stars, but like you said if you could NOT* see the star.....yes, there's a possibility that the dust is being illuminated! However there seems to be a real cluster of stars/dust that surrounds the moon!
    Last edited by pophoto; 2nd August 2012 at 16:45.
    ___________________
    Po-Ming Chu
    POPHOTO

  7. #7
    Senior Member Jim Radcliffe's Avatar
    Join Date
    Mar 2009
    Location
    Texas
    Posts
    627
    Post Thanks / Like
    Images
    8

    I know what caused this now....

    I revisited all the shots and have determined that the "stars" are, in fact, the result of being to heavy handed with the clarity adjustment.

    I used spot metering on the moon itself and had some -EV dialed in. This resullted in under exposure and when I made the compensation in Lightroom this brought out some sensor noise and the clarity adjustment amplified this creating what appeared to be stars. Lesson learned... check the -EV before you shoot the moon.

    So, it's not dust, it's not hot pixels... it is operator error and over-processing in Lightroom (which I am new to) and still learning.

    Having said all that, the stars did look kinda cool... but I will know what not to do in the future.
    Jim Radcliffe
    www.boxedlight.com

  8. #8
    Member kdemas's Avatar
    Join Date
    Dec 2007
    Posts
    248
    Post Thanks / Like

    Re: Seeing Stars with the XP1... this can't be real.

    I actually like the effect, very cool.

  9. #9
    Senior Member
    Join Date
    Aug 2011
    Location
    San Francisco
    Posts
    889
    Post Thanks / Like

    Re: Seeing Stars with the XP1... this can't be real.

    It's hard not to meter the moon when that is all you have!
    ___________________
    Po-Ming Chu
    POPHOTO

Tags for this Thread

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •