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05-04-2007, 07:36 AM   #16
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QuoteOriginally posted by RiceHigh Quote
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.
RC, you obviously didn't actually read the OP or look at the photos posted afterward and in typical fashion have completely missed the mark.

This is NOT a DR issue.

05-04-2007, 09:44 AM   #17
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QuoteOriginally posted by Ole Quote
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?
QuoteOriginally posted by jeff1101 Quote
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.
QuoteOriginally posted by RiceHigh Quote
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.
Sometimes I don't believe what I read. Do you guys believe your own words?

Ole: What should a filter causing the problem you see in the pictures look like?

jeff1101: Let's step back 2 weeks in time. What should your advice be then?

RiceHigh: What? You say those pictures are normal?

Here is a guy having some serious troubles, living at some rural place far from any "expertise" so he asks us. The least we can do is to try to help. If we read his post and look at his pictures we can choose between replying or not to reply. Who of you would find the results of Pelham's efforts reasonably if you had been in his situation?
05-04-2007, 10:40 AM   #18
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This is not blooming, chromatic aberration, dynamic range, or filter reflection issue. However, these combined with lens flare do have similar symptoms to the problem in these photos. The colors of the stripes is close to those of chromatic aberration. The streaking, starting at a bright point and fading as it moves away, is similar to lens flare. Both of the images do suffer from blooming, just not around the point of interest and not the cause of the stripes.

In short, I wonder if the sensor, or the image processor, are getting confused by the scene, which does suffer from many of the above problems. Since nobody else is having this problem it does not seem to be a problem with the sensor or processor design, although RiceHigh will make it into a Pentax conspiracy to shoot off their own foot. I think you need to have the camera repaired. The good news is that I do believe that it is a repairable issue.
05-04-2007, 11:23 AM   #19
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I have not had to deal with Pentax warranty, but when dealing with manufacter's warranty repairs, I've found that if the item in question runs with any sort of firmware they usually question whether it is the current firmware or not and sometimes ask that the user update it first. That I believe would be a reasonable thing to check in a lot of cases, but in this case I side with davemdsm, it looks like it needs some tech's tlc, and not a new filter, lens, or firmware. If it is not the current firmware I bet it comes back with the current firmware installed. I also see no reason why Pentax couldn't/wouldn't be able to fix it or replace it.

05-04-2007, 12:22 PM   #20
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Thanks for the advise

I do appreciate all the advise.. I have installed the latest firmware. It does look like my only real choice is to send it to Pentax for repair. I just wish I had picked up on this earlier in the game and could have simply swapped it back for a replacement. Oh well.. It is the doing with out the camera for a few weeks that makes it a big issue for me.. I generally use it daily. I can put my little Canon A640 to use for a while.
I was hoping that these pictures I posted could generate a difinitive diagnosis of some sort but it looks like technology ain't so easy.. so, I'll send it to the Pentax geeks and hope they return it in mint condition.
Thanks again for all the advise and suggestions.. I'll continue to check this forum to see if any new ideas emerge!!!!
BOB
05-04-2007, 01:58 PM   #21
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Wait a second...

QuoteOriginally posted by Pelham Quote
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.
You know, I have a feeling that you are getting a secondary reflection off of the sensor surface. Have you had an opportunity to look at the sensor and see if there may be telltale film i.e. produced by fine oil or residue? I am sorry, I didn't read the whole thread, so I want to know the lens you are using as well. Do you wear glasses when you shoot? There is a reason I ask this question. Were you wearing sun glasses?

To me it looks like mirror box internal reflection bouncing off of the pentaprism. I wish I had the camera to look inside with the mirror locked up. It is too symetrical to be a sensor problem. Of course it might be but it sure looks suspect.

None the less get back to me asap and I will continue to study the anomaly.

Ben
05-04-2007, 02:46 PM   #22
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QuoteOriginally posted by benjikan Quote
You know, I have a feeling that you are getting a secondary reflection off of the sensor surface. Have you had an opportunity to look at the sensor and see if there may be telltale film i.e. produced by fine oil or residue? I am sorry, I didn't read the whole thread, so I want to know the lens you are using as well. Do you wear glasses when you shoot? There is a reason I ask this question. Were you wearing sun glasses?

To me it looks like mirror box internal reflection bouncing off of the pentaprism. I wish I had the camera to look inside with the mirror locked up. It is too symetrical to be a sensor problem. Of course it might be but it sure looks suspect.

None the less get back to me asap and I will continue to study the anomaly.

Ben
Ben.. I was using the 18/55 lens.. but I have no problem duplicating with any lens. I do not wear glasses of any sort.. this problem will duplicate whenever a high contrast shot is taken.. what I don't know is why sometimes magenta and sometimes green...
Thanks
05-04-2007, 03:39 PM   #23
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Strange

QuoteOriginally posted by Ole Quote
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?
It seems that you have a very valid point here. Look at the symmetry of the reflections that seem to mirror in negative what is occurring in the highlights. It seems that something is kicking back in to the sensor. I suspect this only happens under adverse and challenging lighting conditions? I'm wondering if it has to do with the mirror not closing completely and is at a slight angle kicking some light back in to the sensor. I'm just thinking out loud. Magenta, Green..Hmm, Pentaprism perhaps..Gee,This is a real conundrum...

05-04-2007, 04:59 PM   #24
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Something wrong in the optical path probably

QuoteOriginally posted by benjikan Quote
It seems that you have a very valid point here. Look at the symmetry of the reflections that seem to mirror in negative what is occurring in the highlights. It seems that something is kicking back in to the sensor. I suspect this only happens under adverse and challenging lighting conditions? I'm wondering if it has to do with the mirror not closing completely and is at a slight angle kicking some light back in to the sensor. I'm just thinking out loud. Magenta, Green..Hmm, Pentaprism perhaps..Gee,This is a real conundrum...
You are right it does look like an optical phenomenon - I wonder if the coating on the underside of the mirror is defective?

Either way its probably a straight replacement job for Pentax.

Pain though.
05-04-2007, 07:19 PM   #25
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QuoteQuote:
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.
Why does that make you uncomfortable? Pentax is a reliable company and has the warranty on your equipment.

So what if they fix it rather than replace it? They fix it - just like Ford does with a bad water pump.
05-05-2007, 12:58 AM   #26
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The lighteffects seems to be perfectly horizontal, therefore I think it's a sensor problem. A reflection could/would appear in all directions.
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