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09-17-2016, 12:39 PM   #16
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QuoteOriginally posted by Gimbal Quote
I'm not convinced yet that there are any K-1 that does not look like this at 30sec and iso 6400.
The problem is that having noise in the black level at ISO6400 is pretty much the case of all sensors. If I shoot ISO400 for 5 minutes exposure, I don't see any white dots. If I increase ISO, I start seeing noise and at 6400 iso, I have small white dots even with exposures shorter than 30 seconds.

QuoteOriginally posted by tburn621 Quote
Originally posted by biz-engineer Quote I'm going to return mine as well because it is not free of noise at ISO6400 ! After doing the test, found out mine has both the dots and bar. Called the camera shop where I purchased it and this was the first they heard of the problem. I've done some long exposures but always with in camera NR on. Wouldn't know anything is wrong. Really love the camera! Hopefully Ricoh/Pentax will get to this figured out in short order.
I was being ironic here. I would not be surprised if all cameras have noise at ISO6400 , except maybe the A7s or RED Dragon having much larger pixels.

09-17-2016, 01:00 PM   #17
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Pentax K1 dark frame (without low iso noise reduction), 100% crop, ISO6400 , 30 sec. exposure.
Attached Images
 
09-17-2016, 01:12 PM   #18
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Can't see anything

All parameters set iso 6400, f22, nr off and sr off this is what I got and 30 sec exposure. Doubt I would ever use such a setting though but you never know

https://www.pentaxforums.com/forums/members/75284-pentax-leebo/albums/11125-k1/picture102950.jpg

Last edited by PENTAX LEEBO; 09-17-2016 at 01:19 PM.
09-17-2016, 01:21 PM   #19
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Is that a crop at 100%, or a re-sized full picture?

Edit, I guess it's a full sized picture that is down sampled...


Last edited by Gimbal; 09-17-2016 at 01:29 PM.
09-17-2016, 01:48 PM   #20
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QuoteOriginally posted by Gimbal Quote
Is that a crop at 100%, or a re-sized full picture?

Edit, I guess it's a full sized picture that is down sampled...
Please could you verify in what use would you put the camera to f22 at iso 6400 for 30 secs in real world photography and then crop said photo by 100%. I need a reason for why or what use in photography this would be done?
09-17-2016, 02:07 PM - 1 Like   #21
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QuoteOriginally posted by Gimbal Quote
I'm not convinced yet that there are any K-1 that does not look like this at 30sec and iso 6400.
Me too, actually.
So, than it is "normal" phenotype, not that just few bodies are "problematic".
Looks like situation is common thus I will keep my K-1 and wait if there will be any fix from Ricoh.

I started this thread because I did some star trails with long exposure noise reduction off and results were quite bad.
Just wanted to know how many cameras behave the same way as mine.


QuoteOriginally posted by PENTAX LEEBO Quote
Please could you verify in what use would you put the camera to f22 at iso 6400 for 30 secs in real world photography and then crop said photo by 100%. I need a reason for why or what use in photography this would be done?
Yes, I agree that most probably I will use such setting not so often. I do IR sometimes (with on lens filters) and night photography, so these might be the cases. For birds (that I do most often) this is not a problem.

And it looks like there might be fix already as stated in another thread. So, I will talk to my dealer on Monday and will ask him to contact Ricoh Germany. Also planning to ask about this situation on Photokina.

Thank you very much everyone for participating in this discussion and helping me to figure out what to do.
You are really great community and I enjoy being a part of it.
Best regards,
Yuriy
09-17-2016, 05:29 PM   #22
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QuoteOriginally posted by yurko_yr Quote
There is another thread about this topic. I just would like to see how many cameras are affected and if there are any K-1 without this behavior. I do not have access to other K-1s so cannot tell how common is this thing.
I still can return my camera till Monday or exchange it for another one.
It would not surprise me if the two threads get merged. As for determining incidence...good luck. Past experience has been that when users attempt that on this site those with no problems ignore the thread and those having problems post the same comments as on other existing threads. To put your mind at ease, yes there are K-1 that do not have this problem. The strange thing is that there seems to be a hot spot for "white spot" complaints in Northern Europe. Was there a bad batch all on the same pallet?

As for your best option...If you determine you actually have a problem with white spots or black bar (should be pretty obvious) I would go back to your dealer and request an exchange from dealer stock. If you like, evaluate the replacement at the shop to make sure you have a good camera. Let the dealer deal with Ricoh/Pentax. His account manager will be very sensitive to the matter, I promise


Steve

Last edited by stevebrot; 09-17-2016 at 05:35 PM.
09-17-2016, 07:02 PM   #23
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QuoteOriginally posted by stevebrot Quote
The strange thing is that there seems to be a hot spot for "white spot" complaints in Northern Europe. Was there a bad batch all on the same pallet?
I've got them too but it's not a big deal for me.

Is there a list of serial numbers affected? That'd probably show if it's really just a 'bad' batch for Europe or not.
Mines #6359018, 2nd of March.

09-17-2016, 10:59 PM   #24
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How to figure if your camera has abnormal white dot issue or not?
Read noise from sensor amplifier and A/D conversion at high ISO, should be distinguished from abnormal dark current that become relevant in long exposures. What that means is if white dots appear with long exposure at low ISO (ISO from 100 to 800), then some pixels are defective, and in if that concerns only a few pixels, there is a "pixel mapping" option in the K1 menus (also for other camera models). Still in the same conditions, if there are many white dots, then , returning the camera should be considered.
If there are numerous white dots at high iso such as 6400, it should not be mistaken for defective sensor because there is inevitably read noise becoming significant at high iso, in that case, exchanging camera won't help.

For comparison; everyone can have a look at what 6400 iso noise look like on other cameras such as Canon 5DIII: Zenfolio | ByDawnLight | Camera Noise

Last edited by biz-engineer; 09-17-2016 at 11:36 PM.
09-17-2016, 11:41 PM   #25
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I think a lot of people - definitely me - are now confused about what level of white dots they should be concerned about. My sensor is perfectly clean at low ISOs at 30s but does display white dots, roughly on line with the OP's, at ISO 6400 (30s). Is this a calibration fault or is it a bit of physics that nobody has yet found an answer to? (I haven't seen any black bar issue, but I'm not totally sure how to induce it.)
09-18-2016, 01:03 AM   #26
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QuoteOriginally posted by stevebrot Quote
To put your mind at ease, yes there are K-1 that do not have this problem. The strange thing is that there seems to be a hot spot for "white spot" complaints in Northern Europe. Was there a bad batch all on the same pallet?

Steve
So I understand it as your camera does not exhibit this behavior?
09-18-2016, 06:56 AM   #27
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QuoteOriginally posted by ffking Quote
I think a lot of people - definitely me - are now confused about what level of white dots they should be concerned about.
It's easy. Do two shots: 1) 6400 ISO 30 sec with lo iso NR Off, and 2) with low iso NR On. If you still get white pixels scared across the frame with low ISO NR On, that means it is random noise ; and so it is not sensor defect, but high iso noise instead. If you get white pixels only when setting low ISO NR Off, those white dots are always the same pixels; then it is a sensor issue, and pixel mapping may not detect them.
09-18-2016, 07:05 AM   #28
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QuoteOriginally posted by biz-engineer Quote
It's easy. Do two shots: 1) 6400 ISO 30 sec with lo iso NR Off, and 2) with low iso NR On. If you still get white pixels scared across the frame with low ISO NR On, that means it is random noise ; and so it is not sensor defect. If you get white pixels only when setting low ISO NR Off; then it is a sensor issue.
great - many thanks - in practice there might be a few brighter dots with \nr off, but the picture is 95% similar - it's a bit counter-intuitive to be relieved when you frame with NR on shows noise, but I understand the point - I think I'm happy with the outcome of the tests.

Last edited by ffking; 09-18-2016 at 07:46 AM.
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