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Old Oct 19, 2005, 6:22 PM   #21
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JimC wrote:
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Are you sure about the dead/stuck pixel?┬*┬* Is it only the LCD or is it showing up in your images?┬*┬*┬* Is it hot/stuck or dead?┬*┬* Are you sure it's not dust?

If it's a stuck pixel on the CCD (on all the time and visible in your images at typical shutter speeds),┬* do this:

Set your date on your camera forward a couple of months and save it.

Wait a minute.┬* Then, power cycle it (turn it off, wait┬*a┬*minute, and turn it back on).┬*┬* It should take a┬*longer to come on then.┬*┬*┬* Takes some photos and see if the stuck┬*pixel┬*went away.┬* Repeat if necessary.┬*

Then,┬*set the date back to what it should be and power cycle it again.┬*┬* Let us know if that works (hidden pixel remap function in 7D that remaps pixels periodically based on date┬*is probably in the┬*5D, too).
Thanks for the help on this. I tried exactly what you suggested, but unfortunately after 4 attempts, the green little pixel hasn't shifted. Funnily enough though, I gained a couple of extra red pixels at one attempt, but disappeared on the next.

Here's a cropped section of a photo I took in low light (to pronounce the green pixel) see it? This dot is visible on all shots in the same place.



It looks like I'll have to take it back on Friday.



On another note, is there a list of good 'old' lenses that are almost a must buy? Might as well kit up with a good arsenal of lenses at these prices.
Great help guys
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Old Oct 19, 2005, 6:33 PM   #22
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The remapping function probably needs a certain amount of brightness in a pixel before in will remap it. So, it's probably not seeing it.

As for lenses, any of the primes are probablygreat choices. If you can get your hands on them at a decent price, I'd personally suggest trying to find the 100mm f/2 and 135mm f/2.8. I used both of these this afternoon. The 100mm f/2 is in a class by itself (IMHO).

These are excellent lenses and they won't add too much wieght to your camera bag.


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Old Oct 19, 2005, 7:24 PM   #23
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Jim. I've been a little more patient with it, and after the 12th time, it looks like the green pixel has finally shifted. I'll take some more shots tomorrow to confirm that, as it's way past my bedtime.
If it has shifted I'll be extremely impressed and grateful for your advice.

How does it do it exactly?


and thank you for the lens recommendation
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Old Oct 20, 2005, 5:49 PM   #24
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Well Jim, I've taken a few shots today, and I am pleased to say that the little green pixel has been remapped.

Thank you so much, you saved me a big hassle
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Old Oct 21, 2005, 12:03 AM   #25
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Punce wrote:
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Jim. I've been a little more patient with it, and after the 12th time, it looks like the green pixel has finally shifted. I'll take some more shots tomorrow to confirm that, as it's way past my bedtime.
If it has shifted I'll be extremely impressed and grateful for your advice.

How does it do it exactly?
Most newer sensors are going to have some bad pixels.

You just don't see them when cameras come from the factory, because they're already mapped out.

It's also not uncommon for a CCD to develop more bad pixels as a camera ages.

Basically,a manufacturer is keeping a bad pixel table in memory (EEPROM), and it interpolates around them during processing (taking values from adjacent pixels and replacing them). Since you've got 6 Million of them, a few bad onesaren'tgoing to make any difference if they're mapped out.

With older camera models, when you had a bad pixel (either dead or stuck on) the manufacturer's typically ran a service program to update the bad pixel map. Most consumers thought the CCD was being replaced, when the camera's image processing is just interpolating to replace the bad ones. ;-)

You can find software to update some models yourself now (for a number of consumer cameras made by Nikon, Olympus and others). You can even find software to update the bad pixel table in some DSLR models (for example, the Nikon D100). This software is not supported by the manufacturers (hackers figured out how to call the hidden routines in the cameras).

With some newer cameras, the manufacturers started finding a way to let the camera do it without the need for separate service software. Olympus started it first (AFAIK), beginning with their Olympus E10 Model (this 4MP 2/3" Olympus desginedCCD was very bad for getting stuck pixels, so they came out with a firmware upgrade designed to let the user call the service routine to check for them and map them out). Most newer models from Olympus also have a menu choice to remap bad pixels (even though they're not using Olympus designed sensors).

KM apparently put in an Automatic routine to check for bad pixels and map them out monthly in some of their newer models. I've never seen it officially confirmed. But, more than one user has reported that it works (and you can fool the camera into running the bad pixel remap by setting the date up on the camera). Neat feature.


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Old Oct 21, 2005, 11:43 AM   #26
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JimC Now that you are talking about dead pixels,I have an old Olympus c-3030 that I want to give away, but it has a few dead pixels on it,I feel kinda bad giving this away with them on the photos, do you by any chanceifI can remap this camera ? or what was the software you mentioned ? :roll:

Thanks



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Old Oct 21, 2005, 12:19 PM   #27
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Shanti wrote:
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JimC Now that you are talking about dead pixels,I have an old Olympus c-3030 that I want to give away, but it has a few dead pixels on it,I feel kinda bad giving this away with them on the photos, do you by any chanceifI can remap this camera ? or what was the software you mentioned ? :roll:

Here you go.

I'd make sure the battery isfully charged so that nothing interrupts it since it will be writing to EEPROM when it updates the bad pixel table and you don't want to corrupt it with a power problem in the middle of a write (just in case something other than the bad pixellist is impacted).

Use at your own risk. Others have reported that it does work on a C-3030z via a serial cable connection from aPC.

http://e2500.narod.ru/ccd_defect_e.htm

Jim C.


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Old Oct 21, 2005, 3:38 PM   #28
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This deserves a thread of its own as it's excellent info. I also have the Olympus C-2020 Z which has 3 bad pixels, and I didn't even think such a thing was possible. Might give it a go.

Back on topic: Are Tamron and Sigma 'old' lenses worth getting or avoiding? I'm looking at a Tamron f3.8 80-210 at the moment for a decent price.
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Old Oct 21, 2005, 7:07 PM   #29
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JimC wrote:
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Here you go.

I'd make sure the battery isfully charged so that nothing interrupts it since it will be writing to EEPROM when it updates the bad pixel table and you don't want to corrupt it with a power problem in the middle of a write (just in case something other than the bad pixellist is impacted).

Use at your own risk. Others have reported that it does work on a C-3030z via a serial cable connection from aPC.

http://e2500.narod.ru/ccd_defect_e.htm

Jim C.

Thanks!!!

Now i just need a Serial cable :-)



Shanti Castillo G.
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Old Oct 21, 2005, 7:33 PM   #30
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Olympus Serial Cables on Ebay
(around $10+ shipping, and some of the vendors here listing them do ship to Mexico if you can't find one closer to you). You might be able to dig aroundand find the pinouts if you want to make one for it with available connectors.

B&HinNYhas them, too (about $26.95 for the genuine Olympus cable).

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