Why the reflections?

Discussion in 'Nikon' started by christina_santavicca, Nov 27, 2009.

  1. Can somebody please explain why I get these reflections. Also, please ignore any raw/WB/exposure or focus issues. These images are junk images, just for the sake of figuring out the problem. Thank you! Also, no flash was used on any of these images, and these were taken with a D60.
    00V7LO-195219584.jpg
     
  2. Looks like ghosting, do you have a filter on your lens?
     
  3. It is a ghost image. Try taking the filter off of your lens
     
  4. Well, for examples 2 and 3, I believe I had a UV filter on, but I cannot remember for #1. What would cause the filter to do this?
     
  5. Are you using a UV or other protective filter on the lens? Inexpensive ones can sometimes be misaligned in their metal mounts and reflect the reflection off of the front of the lens back into the lens, if that makes sense. In other words, the front element of the lens bounces some light back, then it hits the inner surface of the filter, and this is then bounced back into the lens.
     
  6. Ok. I understand what you are saying, but would that cause it (the reflection) to be upside down like it is?
     
  7. Yes, because if you look at the front of your lens, scenes reflected in it are upside down, shrunk due to the convexity of the lens surface, and tinted bluish or greenish or purplish, just like your ghost images. The filter only has to be very slightly misaligned in its metal ring to shift the secondary reflection off to the side like its doing.
     
  8. I see. Well, do you have a suggested technique to be sure the filters are on correctly?
     
  9. A quality filter with good multi-coating (like those from B+W) will help to minimize this - quite a lot, actually. I frequently shoot into bright light sources with filters mounted, and have only ever had this problem (to this degree) when using cheap, uncoated filters.
     
  10. If they are screwing in properly, with no resistance as you turn the threads, it just may be that they are either misaligned in their mounts or are not of equal thickness throughout the glass part. By "misaligned in their mounts," I mean that the glass, as assembled in the threaded ring, is not exactly perpendicular to the lens axis (an imaginary line going dead-straight through the center of the lens) when it is screwed in. Such filters should be replaced. Off-brands are more known for this problem, while the best brands, such as B+W among many other top brands I could mention, rarely if ever show it. Of course, top brands cost a lot more than cheap ones.
    But be warned - even a perfect filter can reflect a strong light source's image, bouncing off of the front element, back into the lens when that light source is off to the side in a contrasty scene with a dark background. I've had it happen in night shots with the moon, and in those situations, just take the filter off.
     
  11. Another possibility is a reflection from the digital sensor. This is one of the reasons why nikon developed the nano crystal coat.
    In this link there is an explanation from Nikon, see point 2 in the article
     
  12. Nice example why one should not use these filters...
     
  13. Things like this to a certain degree also happen without filters with certain lenses, the 50/1.8D is a common example. Noct lenses are designed to minimize flare.
     
  14. Yeah, Michael, that's kind of what I'm thinking too. And Francisco, thanks for the link. Matt, Lewis and everyone else, thank you so greatly for the assistance and the insight. Hope everyone had a great Thanksgiving!! :)
     
  15. --->The correct way to use a UV filter is to take it off the lens and throw it away.
    I have many thousands of dollars of Nikon lenses. None have a UV filter on them for exactly the reason you illustrated. Protect the lens with the lens cap.
    Kent in SD
     
  16. This thread exemplifies exactly why I don't use UV filters any more - lens shades protect my lenses.
     
  17. Great. Point taken & Lesson learned. Thank you! : )
     
  18. I second the answer of Francisco.
    When we used film, there was hardly any reflection from the surface of the medium.
    Now with shiny sensors, the projected image is reflected and returned into the glass.
    That is why some lenses and filters now have special coatings: to kill reflections in the system.
     
  19. Why don't they make the sensors less shiny?
     

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