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11-06-2010, 01:53 PM   #16
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QuoteOriginally posted by telfish Quote
No hot pixels here, why would Nikon release a body without pixel mapping in camera? This is basic stuff.
I find not having pixel mapping in any DSLR a bit backward thinking.All sensors will develop hot/stuck/dark pixels with time.My K10D had 3 such defective pixels when i first got it.The K10D did not have pixel mapping,but was a non issue as i shot only raw.My K20D/K7 had a few initially,but were easily mapped out in camera.

Those who shoot jpeg only should not be at a disadvantage with K5, easily mapped out in camera.no need to cart your camera off for this to be done.This is another great seldom mentioned feature that even the entry model Pentax boast.

11-06-2010, 02:41 PM   #17
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QuoteOriginally posted by telfish Quote
why would Nikon release a body without pixel mapping in camera? This is basic stuff.
Nikons don't do pixel mapping in camera. The D90 didn't, the D7000 doesn't, ditto for D700, D3 series etc.
11-06-2010, 02:51 PM   #18
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Just did a 1041 second exposure without any hot pixels, iso 80.
11-06-2010, 04:00 PM   #19
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QuoteOriginally posted by buaobao Quote
Wow ! it produce "so many stars".

Is it possible that the reason nikon d7k sell at lower price is that they use mostly rejects-refurbished sensor sort of, or i might be misinformed.

buaobao
Not likely at all but it's a fine rumor.

Do we have a section for Patently False Nikon Rumors? Should do. Adam ??

11-06-2010, 04:06 PM   #20
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Is a hot pixel an undressed one ?
11-06-2010, 04:13 PM   #21
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No hot pixels here.
This should put to rest the theory that Nikon is not without fault.
11-06-2010, 05:02 PM   #22
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I was not aware than Nikon have no pixel mapping. This is another + for Pentax
11-06-2010, 05:40 PM   #23
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Bad isn't the word for it. That looks like a defective sensor. I initially thought they were stars, but then stars don't fall on the beach - unless you are a poet.

11-06-2010, 08:52 PM   #24
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I believe the appropriate quote is:

"My God, it's full of stars!"
11-06-2010, 10:16 PM   #25
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The K-7 originally had a false-hot-pixel problem when set to Mirror-Up mode. It appeared even in RAW shots, but not when set to normal shooting mode. I took a test shot once and counted easily 50-60 "hot pixels".

Something to do with signal processing, and it was fixed after the first Firmware update.
ditto the "Green Line" problem which appeared in some units.

dSLRs are complex machines. Sometimes what appears to be a sensor issue is not...

Anyway, Nikon's lack of User-accessed Pixel mapping looks like a definite wrinkle....especially with Video, because its a pain with hot-pixels appearing in every single frame at 24 or 25 fps...
11-06-2010, 11:43 PM   #26
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QuoteOriginally posted by Cannikin Quote
I believe the appropriate quote is:

"My God, it's full of stars!"
Nice movie quote!
11-09-2010, 07:34 PM   #27
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Ummm The hot pixel issue on the d7000 is during VIDEO... for some reason. Though I wouldn't have thought it would make a difference.
11-09-2010, 08:50 PM   #28
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QuoteOriginally posted by Chaitanya Quote
Even I am worried about K-5 as it is sharing a similar sensor to Nikon D7000 and after reading those initial bad user reviews. I am postponed my plans of buying K-5 till mid next so that there will be sufficient time for the company to solve problems.
Agree with Creampuff on this. We just had the monthly Pentax gathering here in Singapore with many K5 users (me included). This was a night shoot starting from sundown (7pm) till near midnight (11pm for me). No obvious issues with hot pixels. So these fears are baseless and unfounded.




We can easily map out any hot pixels anyway, which is not the case for a D7K, which has to go to the service center.



QuoteOriginally posted by creampuff Quote
Well I was with many other Pentax users shooting night shots yesterday and I have to say your fears are baseless and unfounded.
I shot many long exposure shots and video over a 5 hour period and didn't encounter any hot pixel issue with my K-5.


11-09-2010, 09:00 PM   #29
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Just to explain.

The pixel map feature with Pentax is great and solves any such problem for Pentax still photography.

However, pixel mapping cannot work for video and live view. Because only some out of all pixels are read at all and the firmware cannot control which ones.

So, some of the hot pixels can make it into video and there aren't mapped out. Moreover, hot pixels get brighter with increasing temperature as is normal in video. So, hot pixels are more normal towards the end of video clips. You then see them in LV too.

So far, we have no reports of hot pixels in video. That's a good thing. But I think it's too early to say if the problem only strikes Nikon or not.

FWIW, I know that some K-7 can show a few hot pixels in longer videos. If at all, 1 or 2 and often red and only visible against dark background.


If for some reason the problem now strikes Nikon but not Pentax then it would be great. Maybe, the sensor stays cooler on Pentax or Pentax introduced some quality control before using a sensor? The Pentax sensors are mounted to the SR board and I don't see that it cannot be plugged into a tester. If the latter is the case, Pentax should tell us as it is a real bonus wrt D7000.
11-10-2010, 02:51 AM   #30
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QuoteOriginally posted by falconeye Quote
However, pixel mapping cannot work for video and live view. Because only some out of all pixels are read at all and the firmware cannot control which ones.
I see your point that the original hot pixel map cannot be used.

However, the original hot pixel map could be used by using a mapping of the subsampled pixel positions to their original positions.

A less space-efficient but quicker method would be to use a dedicated hot pixel map for video (would probably have to be computed on the fly at the beginning of a video recording because it differs for all video modes).
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