If this is your first visit, be sure to check out the FAQ by clicking the link above. You may have to register before you can post: click the register link above to proceed. To start viewing messages, select the forum that you want to visit from the selection below. |
|
|
|
Thread Tools | Display Modes |
#1
|
|||
|
|||
D200 owners, pls do a test for me (and for yourselves)
Hi all,
I have had a D200 for about eight months, and while I generally love it, it has been plagued with a disturbing number of problems. First was the long banding--I believe they replaced the sensor to fix that, but afterward pixels started dying. First I had three dead pixels remapped, then two months later I found about 20 new ones, which were remapped. Now, a month later I am finding more. Has anyone else experienced anything like this? But the latest and greatest weirdness became apparent recently when I tried to do a longish exposure--about 3 minutes--of the African night sky. I was shocked to find that all four corners and the top of the frame were luminous pink--looking like light-struck film. And the whole frame was studded with scores of dead-looking pixels of different sizes in white, red and blue. But they weren't dead; at shorter exposure times they behaved normally, with more and more being "blown out" and luminescing as the exposure lengthened. There were a few at 30 secs., more at one minute, and a whole lot more at 3 mins. I didn't have the courage to test further...Likewise the pink fringing started at about 1 minute and grew progressively worse at longer exposure times. Obviously this is going back to Nikon, but I am wondering how many D200 exemplars might suffer from this kind of defect, which is not obvious in most shooting situations. If you have a D200 and the time and inclination please try this: Go in a dark room, put a body cap on to stop any light from entering at the front, and perhaps the cap on the eyepiece as well, and do a 3 minute exposure at ISO 1600. I would be interested in hearing about the results. TIA, Toby |
#2
|
|||
|
|||
D200 owners, pls do a test for me (and for yourselves)
My D70s has a "long exposure noise reduction" setting - have you got this
setting in use? |
#3
|
|||
|
|||
D200 owners, pls do a test for me (and for yourselves)
|
#4
|
|||
|
|||
D200 owners, pls do a test for me (and for yourselves)
Doug Payne wrote:
On 30/08/2006 10:39 AM, wrote: And the whole frame was studded with scores of dead-looking pixels of different sizes in white, red and blue. But they weren't dead; at shorter exposure times they behaved normally, with more and more being "blown out" and luminescing as the exposure lengthened. That's long-exposure noise, not dead pixels. Red, white and blue are not dead pixels, they are 'hot' pixels and Long Exposure NR (dark frame subtraction) eliminates them - in theory along with the pink glow. David |
#5
|
|||
|
|||
D200 owners, pls do a test for me (and for yourselves)
|
#6
|
|||
|
|||
D200 owners, pls do a test for me (and for yourselves)
Doug Payne wrote:
On 30/08/2006 10:39 AM, wrote: And the whole frame was studded with scores of dead-looking pixels of different sizes in white, red and blue. But they weren't dead; at shorter exposure times they behaved normally, with more and more being "blown out" and luminescing as the exposure lengthened. That's long-exposure noise, not dead pixels. OP wasn't complaining about dead pixels, OP was complaining about pink and color noise. -- Thomas T. Veldhouse Key Fingerprint: 2DB9 813F F510 82C2 E1AE 34D0 D69D 1EDC D5EC AED1 |
#7
|
|||
|
|||
D200 owners, pls do a test for me (and for yourselves)
On 30/08/2006 1:46 PM, Thomas T. Veldhouse wrote:
Doug Payne wrote: On 30/08/2006 10:39 AM, wrote: And the whole frame was studded with scores of dead-looking pixels of different sizes in white, red and blue. But they weren't dead; at shorter exposure times they behaved normally, with more and more being "blown out" and luminescing as the exposure lengthened. That's long-exposure noise, not dead pixels. OP wasn't complaining about dead pixels, OP was complaining about pink and color noise. OP said this: And the whole frame was studded with scores of dead-looking pixels of different sizes in white, red and blue. Picky semantics. Get a life. |
#8
|
|||
|
|||
D200 owners, pls do a test for me (and for yourselves)
Bill wrote: I've heard of that...I think it's just too much signal gain at high ISO settings in dark shots. Lower the ISO to a more appropriate setting. It's because of heat coming from electronic circuits near the sensor. Not entirely surprising after an exposure of 3 minutes at ISO 1600. It is removed, as you say, by dark frame subtraction. You should already know this, but those are called "hot pixels" and it's actually normal. The longer the exposure time the more hot pixels will show. You have a noise reduction (NR) feature in the camera called dark frame subtraction for long exposures. When enabled, it does a secondary exposure without opening the shutter to get a completely dark comparison for the previous shot. It does a decent job of removing the hot pixels and any other anomalies. The ISO setting has an effect on it too. For long exposures you should be using ISO 100. Higher settings are not needed and introduce unwanted noise. Limit high ISO shots to low light, such as indoor shots. For dark or night shots where you have to use a tripod anyway, set the camera for ISO 100 and get the best image quality. Hot pixels happens with all digital cameras. It's nothing new. The only thing of concern is the dead pixels. You shouldn't have that many after only 8 months. |
#10
|
|||
|
|||
D200 owners, pls do a test for me (and for yourselves)
Bill wrote: wrote: I've heard of that...I think it's just too much signal gain at high ISO settings in dark shots. Lower the ISO to a more appropriate setting. It's because of heat coming from electronic circuits near the sensor. Not entirely surprising after an exposure of 3 minutes at ISO 1600. Oh...so cooling the sensor would fix it, like with an icecube? But...how do I get the damn icecube inside the camera. I tried putting it inside the sensor chamber, but then it blocks some of the light. I shoved one in the battery slot, but then the camera don't work. I even tried using the blender to chop up the icecube and shove the little bits into the CF card slot, but still no good. What am I doing wrong??? One of these should do the trick: http://atlas-magnet.web.cern.ch/atla...y/photos/pump/ |
|
Thread Tools | |
Display Modes | |
|
|