Hot Pixels

[JBF]

Just got my new 5d in the mail. Ran the hot pixel test. At exposures down to 1 sec I saw two hot pixels. At 5 sec exp there were about 8. At 30 Seconds there were around 70. Is this normal and is this OK? Errr, I mean acceptable?

[cmM]

you are bound to have *some* hot pixels, especially if you expose for long.
I'd say it's acceptable.

[Jon]

Seems reasonable, out of 12 MP at those speeds.

[Longwatcher]

Sounds reasonable, but don't forget to see what happens at different ISO values.

I have some that go away above ISO 400 and others that only come in above ISO 800.

[The22oz]

How do you perform a Hot Pixel test? I'm sure its been beaten to death but I figured I'd ask since this post is currently going. Sometimes when you search for things you find that people leave out important information every so often.

[cmM]

How do you perform a Hot Pixel test?

Depends how paranoid you are :)
Personally, I tried it once when i downloaded it to see just for curiousity, and my next test will be whenever I notice them on my pictures. Until then, it stays zipped ;)

[adas]

JBF, there are two kind of hot pixels, occasional and permanent.
The occasional is not even a hot pixel, most likely the static lifts up the charge on random pixels. It wouldn't show up in two pictures at the same location.
The permanent hot pixel is caused by pixel ununiformities at the production time, and will show up on every picture taken with a relatively slow shutter speed.

So you would have to repeat the test using the same times, to see wich is wich.

The worse is the dead pixel, that is an absolutely defectuous pixel. To do the test on it, you take the picture with lens cap on at a shutter speed of 1/100 or higher.

[JBF]

Thanks, just ran the dead pixel test on the 5D at 1/100th. Nada!!! So I guess the sensor is fine. Actually the hot pixels I found at the 30sec exposure, barely even showed up until I got the image blown up to 1600%. Doubt that I will ever need anything blown up to that size. Well, Unless I get a gig doing billboards.

Thanks for all the input. Oh, by the way, when my 5D arrived today, much to my surprise the menu was in Japanese. Would this be a gray market camera? I have bought many things from B & H in the past and was never sold a gray market item before.

[Mark_Cohran]

Thanks, just ran the dead pixel test on the 5D at 1/100th. Nada!!! So I guess the sensor is fine. Actually the hot pixels I found at the 30sec exposure, barely even showed up until I got the image blown up to 1600%. Doubt that I will ever need anything blown up to that size. Well, Unless I get a gig doing billboards.

Thanks for all the input. Oh, by the way, when my 5D arrived today, much to my surprise the menu was in Japanese. Would this be a gray market camera? I have bought many things from B & H in the past and was never sold a gray market item before.

When you order from B&H you have to specify whether you want an parallel import (gray) or a US import. If you got a US warranty card with your camera, you have US model. If you did not get a US warranty card, you received a parallel import. You need to check your invoice to see what you ordered and compare it to what you recevied.

You can change the menu language, so it just might be that it was mis-set before shipping. Was the box sealed?

Mark

[JBF]

I called B & H today. They told me they do no sell gray products (in digital camera's) I know they do with lens. It has a US/Canada warranty card. However, the box was not sealed. The warranty card looks exactely the same as my 20D warranty card. Must be ok. (I hope) Heck if it takes good crisp pictures, I don't care where it's from.

[StealthLude]

Dude, 70 hot? .....

I do 30+ second shots with a 20D and i get 2-3 at the MOST!!!

70 Hot, there is something wrong! call canon.

[JBF]

Ok, OK. This was about to drive me crazy so I thought I would run one more test. A comparison from the 20D to the 5D I shot 4 Different shots each at ISO 100, 400, 800 and 1600 on both camera's. All were exposed at 30sec, with the lens cap on. Here are the results:
20D
ISO 100 11 Hot pixels
ISO 400 36 Hot Pixels
ISO 800 73 Hot Pixels
ISO 1600 141 Hot Pixels

5D
ISO 100 0 Hot Pixels
ISO 400 5 Hot Pixels
ISO 800 7 Hot Pixels
ISO 1600 52 Hot Pixels

I don't feel so bad now. Looks like the 5D wins hands down.

[kram]

Well, Unless I get a gig doing billboards.



Then, get someone to work for you on CS2 for all such billboard work (prob. 5 mins per billboard) and get the pixels out.

The numbers look small, I wouldnt worry. Enjoy the new 5D.

[RJCONKLIN]

i have some questions about hot and dead pics. since a digital camera is an instrument, should'nt the factory send a spec. sheet with each camera giving the amount of hot and dead pics at different iso's and times? also state the upper limit there of, or is this too simplistic?

would'nt this save the camera co. the camera owner and the store where purchased a lot of grief, returns?

finally, does anyone know what the acceptiable limits are? if not, why not. cameras costing $1000.00 to $8000.00 should provide this information. maybe if the photographic professionals bitch enough to the factory and forums like this one, something will be done.

[JBF]

I agree, but I doubt you will find a company that makes digital imaging sensors that will admit to how many hot or dead pixels are on one particular sensor. If that were the case, then I would make the retailer open every box and I would take the one with the least amount of hot pixels.

[RJCONKLIN]

I agree, but I doubt you will find a company that makes digital imaging sensors that will admit to how many hot or dead pixels are on one particular sensor. If that were the case, then I would make the retailer open every box and I would take the one with the least amount of hot pixels.

if there was a standard that was accepted to be normal; i mean, how can you have an instrument with no calibration standard. this is not accepted in anything manufactured.
professional photographic orgi****ations must lobby for a standard, espically the national association of photoshop professionals. the chip and camera manufactures have acceptable standards. they must publish them. this hot and dead pixel problem is rampent throughout all forums.

[Steve Parr]

My 300D has some pixels which show up white in the images. They're in the same place, every time. More noticeable in a darker image.

Would these pixels be dead or hot?

Steve

[RJCONKLIN]

white pixels are dead pixels

[JBF]

I'd send your camera back. Dead Pixels will show up every time you take a pic. Hot pixels aren't as bad.

[Jon]

i have some questions about hot and dead pics. since a digital camera is an instrument, should'nt the factory send a spec. sheet with each camera giving the amount of hot and dead pics at different iso's and times? also state the upper limit there of, or is this too simplistic?

would'nt this save the camera co. the camera owner and the store where purchased a lot of grief, returns?

finally, does anyone know what the acceptiable limits are? if not, why not. cameras costing $1000.00 to $8000.00 should provide this information. maybe if the photographic professionals bitch enough to the factory and forums like this one, something will be done.
You ever priced out the cost of 100% testing of the sensor in the completed camera? You really want to pay for this, and the assurance that yields will go down since Joe Public will insist that his 47 GP camera have absolutely no, nada, none, dead pixels at 2 hour exposure and ISO 12800 because otherwise his 4x6 prints taken at the beach will be irretrievably marred? Thanks, I'll live with the chance of finding 30-40 pixels out of 8 million on my 30 sec. exposure either hot or dead.

[RJCONKLIN]

the point is jon, if there was a quanitive standard it would avoid confusion and dilusion.
camera owners would know whether to take the camera back to the store or send it in for repair.

i would hope to hell that canon test every camera sensor. i am sure the factory would have a computerized quick method. otherwise we should all send our cameras to the factory on general principals. every car co. runs every engine.

[Eugene.S]

I'd send your camera back. Dead Pixels will show up every time you take a pic. Hot pixels aren't as bad.
How about,if you will receive new one with more dead pixels?
When I bought my 1D MKIIN i tested 5!!! brand new bodies ( i have a good friend from Canon head office) The same situation. Some bodies ( 5 dead 4 hot ) some ( 2 dead 8 hot ) and no one with zero. I think this is normal for Canon's "professional level"

[Eagle]

Don't forget to cover the viewfinder as well as having the lens cap on so no light can get in.

Ran the test on my 20D and got:
ISO 200 @ 1/30" - 0 hot - 0 dead
ISO 200 @ 1" - 0 hot - 0 dead
ISO 200 @ 2" - 0 hot - 0 dead
ISO 200 @ 30" - 12 hot - 2 dead (didn't have the viewfinder covered so I'll have to check again)
ISO 100 @ 1/30" - 2 hot - 0 dead
ISO 400 @ 1/30" - 0 hot - 0 dead
ISO 800 @ 1/30" - 0 hot - 0 dead
ISO 1600 @ 1/30" - 0 hot - 0 dead
ISO 3200 @ 1/30" - 42 hot -0 dead