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05-03-2007, 11:20 AM   #1
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K10D High contrast problem

I have been having a problem when shooting very high contrast shots with my K10D. An example would be taking a picture inside a room with available light and there is a small window with extrememly bright light at the window.. the net result is a band of either green or magenta bleeding out from the over exposed high contrast part of the picture. Sometimes this happens when I am shooting simply outside in the shade, and I am exposed properly for the shade, but there is very bright areas in the background.. I may then get green or magenta streaks virtually crossing the picture from these bright background areas.. Very disturbing to say the least!
Any ideas what might be happening?

05-03-2007, 11:40 AM   #2
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Sounds like an extreme case of "blooming". A sample image would be a lot of help in giving a proper diagnosis.
05-03-2007, 12:13 PM   #3
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Photo post?

I am new to this forum. How do I post a photo? I would like to post a photo to help diagnose this "blooming" problem I am having with high contrast shots.
05-03-2007, 03:31 PM   #4
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If you have a place to host the image it is fairly easy, simple upload the image to the host site, then back here use the "insert image" button in the reply box.

Hosting an image here is a bit of a workaround. First, click on "quick reply" and start typing in the text box. Then click on "go advanced" to get more options. Once there you have the option to "manage images", which is where you will be able to upload to the forum as host.

05-03-2007, 04:26 PM   #5
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QuoteOriginally posted by Pelham Quote
I may then get green or magenta streaks virtually crossing the picture from these bright background areas.. Very disturbing to say the least!
Any ideas what might be happening?
Classic chromatic aberration. (It's a lens thing, not a camera thing.)

See:
Chromatic aberrations
05-03-2007, 05:30 PM   #6
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QuoteOriginally posted by carpents Quote
Classic chromatic aberration. (It's a lens thing, not a camera thing.)

See:
Chromatic aberrations
Chromatic aberration is a thin line around the high contrast line, not a streak across the entire image. As described it does not sound like CA. The description is a little unclear, however, so anything is possible. If we are talking about a DA lens it is highly unlikely that CA would be that bad.
05-03-2007, 05:47 PM   #7
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Contrast problem with my K10D

I know I don't have a lens problem.. I am using DA lenses.. I can duplicate the problem by having the sun brightly hitting a white chair on my deck, then taking a picture of the dark part of my room with the white bright chair overexposed in the image.. this will generate green or magenta stripes horizontally begining at the bright, overexposed area, then banding across the image sometimes dissipating before it actually reaches the opposite side of the image..

OK.. I have made an effort to upload two example photos.. I hope it worked!!!!!

I live in a small town quite a distance from any large city so I don't have any local expertise to talk too.. I would like to take another K10D along side mine and do a compare and see if the other K10D does the same thing.. I doubt if there is another K10D owner within 100 miles of me.
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05-03-2007, 06:29 PM   #8
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I was waiting for the pictures as your description of the problem indicated something strange. To my eyes: you have a faulty camera. If it is new you should have it replaced. Bring the camera and a CD with the pictures to where you bought it and ask for a replacement.

05-03-2007, 07:08 PM   #9
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Wow - yeah, that isn't normal. I agree with Jonas, there is something wrong here.
05-03-2007, 07:11 PM   #10
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I purchased the camera in November of 06.. through a wholesale company in AZ called DBL.. I am a business, so I was able to buy it wholesale.
The problem is, it does fantastic photos as long as this contrast problem is not in the picture.. I had the camera for several months before I discoverd this problem.. I was out there happily shooting nice stuff!! I think my only choice now would be to send it back to Pentax for repair, and that makes me very uncomfortable.. but perhaps thats my only choice short of living with the problem. I doubt Pentax would send me a new body. Do you suppose it has a defective CCD? I wonder if Pentax can satisfactorly replace the chip if that is what is necessary. I am not at all happy about this.
05-03-2007, 07:17 PM   #11
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QuoteOriginally posted by Pelham Quote
I purchased the camera in November of 06.. through a wholesale company in AZ called DBL.. I am a business, so I was able to buy it wholesale.
The problem is, it does fantastic photos as long as this contrast problem is not in the picture.. I had the camera for several months before I discoverd this problem.. I was out there happily shooting nice stuff!! I think my only choice now would be to send it back to Pentax for repair, and that makes me very uncomfortable.. but perhaps thats my only choice short of living with the problem. I doubt Pentax would send me a new body. Do you suppose it has a defective CCD? I wonder if Pentax can satisfactorly replace the chip if that is what is necessary. I am not at all happy about this.
I am sure they can deal with it - its only 6 months old. New CCD should not be an issue - its mounted on a moveable frame after all!! Make sure you enclose the pictures when you send it in so that they have something to base a diagnosis on.....
05-03-2007, 07:20 PM   #12
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There is not necessarily anything wrong with the camera.

Which lens do you use?
Do you have a filter on the lens?

Could it be a reflection, for example from the sensor back out hitting something (e.g. the filter), then reflecting back into the camera?
05-03-2007, 07:45 PM   #13
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No filter... it is the 18-55 lens.. also the 50-200 lens.. but it does it with my other lenses as well.. 50 macro, 100 macro etc..
I have run all sorts of lens tests and it appears that it is in the camera.
A real disapointment.
05-03-2007, 09:16 PM   #14
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Have you tried upgrading the firmware?

At least do this before sending the camera in for repair.
I recently upgraded to ver 1.20 and noticed the camera is no longer underexposing
some of my outdoor shots. (This is definitely not documented in the release though)

So try it first and see.
05-04-2007, 04:01 AM   #15
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What you observe is a limited dynamic range (DR) of digitals, which holds true for any DSLRs. Some DSLRs with larger sensors do often have wider DR, e.g., EOS FF ones, though.

In the same principle which is actually physics, the K100D seems to have slightly wider DR too, than the K10D, e.g., for the reproduction of more shadow details.

QuoteOriginally posted by Pelham Quote
I have been having a problem when shooting very high contrast shots with my K10D. An example would be taking a picture inside a room with available light and there is a small window with extrememly bright light at the window.. the net result is a band of either green or magenta bleeding out from the over exposed high contrast part of the picture. Sometimes this happens when I am shooting simply outside in the shade, and I am exposed properly for the shade, but there is very bright areas in the background.. I may then get green or magenta streaks virtually crossing the picture from these bright background areas.. Very disturbing to say the least!
Any ideas what might be happening?
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