Pattern

philippe · 05-16-2009, 11:24 AM

When viewing my photo's I shot today, one of them showed a new to me pattern in the upper right corner where, just out of the frame, there was a light source. It looks having a graphic kind of structure, are these the pixels?

Thanks for your input,

Philippe

P.S. shot with a brand new K20D and DA* 16-50 mm F 2.8...

asdf · 05-16-2009, 12:14 PM

Originally Posted by philippe

When viewing my photo's I shot today, one of them showed a new to me pattern in the upper right corner where, just out of the frame, there was a light source. It looks having a graphic kind of structure, are these the pixels?

Thanks for your input,

Philippe

P.S. shot with a brand new K20D and DA* 16-50 mm F 2.8...

Maybe, it's lens flare:

Understanding Camera Lens Flare

Was your lens wearing a hood?

iNVision ART · 05-17-2009, 04:36 AM

Maybe there was a smudge on the lens itself??

Bart · 05-17-2009, 05:45 AM

Was this a jpg from the camera or converted from RAW?

My guess would be that this is a jpg artifact.

philippe · 05-17-2009, 06:52 AM

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

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)?

philippe · 05-17-2009, 09:42 AM

Originally Posted by asdf

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)?

Thank you, asdf, to enlighten me!

Philippe