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asdf · 05-17-2009, 09:39 AM

Originally Posted by philippe

Thanks for the answers!

I know it's flare, and yes the original lens hood was mounted.
I have seen flare before, but with a rather gritty and discoloured pattern, not that 'graphic' like this one.
I zoomed in till the light-source (an old fashioned bulb) was just out of the frame, I could not move the camera.
The camera was set on RAW, and in RAW this pattern is there too.
The new lens was, and still is, clean.
Besides converting to jpeg and cutting out the part you see, in Light Room 2.3, nothing was changed.
In P.S. and Preview (Mac OSX) this pattern is clearly visible, so software is not correcting this automatically (like dead pixels in L.R.).
I have to admit that this is my first zoom-lens, I was, and still am, used to (Pentax) primes.
With my K10D, I have never seen this, but that one has a different sensor.
I do not consider this as a major problem, I am rather curious to know what might have happened. I attached a more enlarged detail.

Philippe

It's an artifact of the bayer sensor pattern. It's probably only a coincidence that you haven't seen it before.

Depending on which algorithm you use, to convert from RAW, you will get different patterns:

Aliasing ?(demosaicalgorithms)?

05-17-2009, 09:39 AM	#6
asdf Loyal Member Location: Canada Gallery Photos: 0 Posts: 596	Originally Posted by philippe Thanks for the answers! I know it's flare, and yes the original lens hood was mounted. I have seen flare before, but with a rather gritty and discoloured pattern, not that 'graphic' like this one. I zoomed in till the light-source (an old fashioned bulb) was just out of the frame, I could not move the camera. The camera was set on RAW, and in RAW this pattern is there too. The new lens was, and still is, clean. Besides converting to jpeg and cutting out the part you see, in Light Room 2.3, nothing was changed. In P.S. and Preview (Mac OSX) this pattern is clearly visible, so software is not correcting this automatically (like dead pixels in L.R.). I have to admit that this is my first zoom-lens, I was, and still am, used to (Pentax) primes. With my K10D, I have never seen this, but that one has a different sensor. I do not consider this as a major problem, I am rather curious to know what might have happened. I attached a more enlarged detail. Philippe It's an artifact of the bayer sensor pattern. It's probably only a coincidence that you haven't seen it before. Depending on which algorithm you use, to convert from RAW, you will get different patterns: Aliasing ?(demosaicalgorithms)?