disappearing hot pixels
 

I went to a concert the other night which featured a great Tango Quartet and some professional Tango dancers. I brought along my XLH1 and shot some random stuff during a class before the show, and later the dancers performing before an audience. When I returned home to view the footage, I notice two hot pixels (one of which appeared to be a block of 2-4 pixels) on the footage taken earlier in the evening. Alarmed, as I've never seen this on any video camera I've owned...I forwarded through to the later stuff (during which the camera had been switched off, restarted and gain adjusted)...and walah...no hot pixels on the later footage..

Anyone else ever see this...?

it is common for hot pixels only to be visible under high gain settings - hot pixels can be mapped out by Canon service

What's interesting was that the later footage, in fact, had a higher gain setting than the earlier stuff...and both areas of hot pixel had completely disappeared...

Could it have just been dust specks?

Anyway, clean the lens, put the lens cap on, crank the gain, and shoot a few seconds of behind-the-lens-cap-black video to see if it appears at max gain as P.R. alluded to.

nah...they were bright white pixels in two spots...one was quite bright...looking like a block of 2 or 4...the other was small, probably just one pixel. and both were very sharp. (Dust would be dark...or if flared...light, but would change with any zooming..possibly sharp at widest settings, but would blur and then disappear when zoomed in). these were in the same position (and sharpness) at all zoom levels...hot pixels. and then...no hot pixels.

I will be checking everything again, I just was curious if anyone else had seen this before...

Barry

Barry, I have seen this with my H1. I see 2 hot pixels from time to time. It is more often with gain at +6 and a a slowere shutter speed but they appear from time to time. One is blue and one is red. I have been contemplating sending it in to have these pixels mapped out but do not know what the charge would be.

Anyone have a rough idea what Canon would charge for this service?

Ha, Marty...I knew it would be you...

I think it's interesting....Mine popped up when my gain was at +6 as well...but when I increased it to +12 (after turning the camera off) they disappeared...which of course makes no sense...I'll report back if I see them again.

how sporadic has yours been?...I don't use my camera a lot...but I'm hoping this was just a one time event.BG

Off the top of my head I would say that I have seen it 3-4 times in the last year. I was testing a LetusXL the other day and it this adapter eats light for lunch. I was indoors so I stepped up the gain to +6 and I didn't see it. But when I pushed it to +12 they showed up. Then I stepped back down to +6 and they were visible still. All the way down to zero and I could barely make them out.

Later, when I started at 0 they were gone. Is is possible these things actually "heat" up when set to higher gain and then cool down? I wouldn't think so but I guess it is possible cause they aren't there, appear after gaining up and then linger.....hmmmm....

I'm just thinking of something...we had a bit of rain and tropical humidity that day (which is unusual here in Southern California, especially after a week of wildfires)...the room we were in was heated, but this was after a long walk across campus to the auditorium...I'm wondering if humidity was the culprit...and after I'd been in the room for 45minutes with the heater on...things dried out....

hmmm.

I too have rashes of hot pixels which come and go.

Has anyone had any success in getting Canon to fix this in their service department?

Harry

i took mine in to canon in irvine about a month ago for the exact same problem. it was $240 to map the pixels, they did a cleaning and firmware update. still pretty steep for something like that on a prosumer cam.

Thanks for the reply. I will send mine in to have the pixels mapped out. It's a pain in the neck. I have five scattered all over the screen which come and go, but I am supplying Canon with frame enlargements so, hopefully, they can locate them since, maddeningly, all pixels are working at the moment.

Harry.

I also see one hot pixel now and then. So annoying. I might ship mine to Canon as well. What a waste of money. Shouldn't happen.

Has anyone found any pattern to this yet? I have 2 of them that come and go. They are really not noticable unless shooting with +3 gain and a slower shutter speed and in a dark setting. I shot in California for a week in January and didn't see a single sign of them. Then, first time I go to shoot back here in Ohio, they pop up. And I can only see them in the viewfinder when I have peaking turned on otherwise I wouldn't have seen them until post on this project.


Bummer.

Interesting,....I had just posted this in the P&S Technik forum...

I had seen this for the first time last summer...using a 35mm adapter...and now...once again...the same pixel...

"We used the adapter 400 series....last week.

After the camera was "warm"...the same pixel that showed up last summer...showed up again. But with the standard 20x lens on...it doesn't.

We were shooting at 0 db in the studio. So...as folks have said...is this just a "feature" of using the adapter...and having the image "smooth"...compaired to a sharper image with the standard lens ?

Or should I have the camera sent back to Canon...to have them map the pixel ?

Thanks....and BTW...I'll post some shots of this...and a small video clip...
Footage looks great...and I used a Cook 18-100 zoom lens."



Some folks suggest that with the use of the 35mm adapter and lens....the contrast ratio may allow the pixel to be "seen". I only have been seeing this pixel when using this adapter...AND....only at 0db...NOT at a higher db setting.

Kevin, I don't think it is something that is created by the adapter. Probably enlarged. I did some test today and I found out that in the highest gain setting, at occasions I have like 15 hot pixels! It is worse when I put the camera in Auto mode, in Night scene mode and in External control mode. With 3db and 0db is it pretty much controlled.... only two clusters of hot pixels that turn on and off in random time intervals. I am pretty angry about this.

The stupid thing is that I haven't really noticed it but when I look back some footage I shot in the past I can see those hot pixels. My camera is now 16 months old so no warranty anymore. I only wished I had seen this earlier while my camera was still under warranty.

I am going to call Canon monday and see what they can do for me. I hope they can fix this. If it costs $240, shit happens, but I will have them fix it. But when I look at the 15 or so hot pixels I saw while testing this phenomena this afternoon I wonder if they shouldn't replace the whole CCD block. I see blue, red and green pixels... (mostly blue) so I guess all three CCDs are affected. It really frightens me.

I really hope they help me out with this otherwise this will be my last Canon camera. From what I read on these forums this is happening to a lot of people, or we are not a representative sample.

If anyone else has contact with Canon let me know what they say.

I shot some test footage and upload it here:

http://www.ecknology.com/temp/hotpixels.mov

Really, how bad is this?

This was captured straight from camera to Final Cut without any processing. I shot some frames with the lens cap still on.

I had the same problems of multiple dead pixels. Sent it to Canon. Paid the dough. No more dead pixels now.

Incidentally there is some pretty good software out there for dead pixel removal.

Best

H

Floris...
I agree. And I'm in the same boat. Camera is 17 months old...and I'll have to pay to have it fixed. Guess the $240 is cheaper than a new camera....but...seems that they have (or should I say HAD) a problem with these blocks.

Well...not too many options...so you either deal with it...or get it fixed.

I would love to hear Canon's comments about it....on this forum....but that might be asking too much.

Kevin, I completely agree with you. I paid like 8700 EURO for this camera so the 250 EURO to fix this is like a small fee on the whole sum. But still, if I read that on these forums like 7 to 8 people have experienced this, it sounds to me like a real problem. And I wonder: if I have Canon fix them, how much of a guarantee is that? Is it possible that two months later another pixels goes hot and I have to pay 250 EURO again? That's something I would like to know. Otherwise I might have them fix it and trade it in for something else.

I will Canon on monday and see how much they charge over here in Europe to fix this. First I am going to argue a bit and see if I can get them fix it for free because this is no normal behavior. The warranty card says 12 months warrantee but in Europe a company is obliged to fix it even out of warranty when behavior is not acceptable within the reasonable. I think that 10 hot pixels on my CCD block is not something I could have prevented. Neither do I believe that it should happen on a 9000 EURO camera after 16 months. So we'll see how this develops.

I will keep everyone updated here.

Harry, after you send it to Canon did all hot pixels disappear, even in the highest gain settings?

Floris, you should be able to get your guarantee cover that in Europe.

I just bought a A1 and I have a cluster of blue/greenish pixels 'dead' if you
like stuck on my footage below right hand side corner. I looks like a good chunck of pixels and I am puzzled about it. Been taking some footage with Steven Dempsey's Panalook and vivid_RBG custom preset's as well as Will Schryver's Rich_RGB and it appears on all settings as well as in the viewer and LCD screen. All was shot HDV at 25f.

Will try see if also apparant in SD and if can will upload a screen shot.

Bloody annoying as I just had the camera 1 week.

Seem I have the same problem as everyone else in this thread, if any one
has had the same 'pixelation problem' please do comment.

Just checked a SD test and the same pixelation is occuring on the footage
there also. Blue/Greenish spots in same positions. I somehow cant make
attachments (guess newbies not allowed) but it is very clear on the screen
shot taken from FCP.

I am wondering whether it could be a lens problem????? but I checked
it with/without the UV filter and cleaned the lens (althou not with any
chemical solutions just the dust clotch) several times now to no avail.
Will see if I can figure a way to attach the screen shots.

Any help will be much much appreciated.

Here is the screen shots both SD and HDV.

Help!!

Henrik,
I am sorry to say that the images you posted look nothing like the problem I am having and I don't think they are lit pixels, at least not the way we are thinking. Mine are little tiny "pin points" of light, like the way a star looks in the night sky, but brighter. I have never seen your problem before and highly recommend you get it looked at immediately. That is not normal.

On a diifernt note, has anyone ever sent there camera in to have the lit pixels remapped and had them "not" fix it right? Since the problem is intermittent, how do we know that Canon will even be able to find the offensive pixels while it is in the shop? I am not dogging Canon, but I have been a bench tech in the past and at times I could not reproduce a problem in the shop, that I believed the client was seeing 100%. It happens.

Thanks.

Floris,
Did you take your link down? I cannot seem to get to it.

Thanks.

I fixed the link. I agree with you Marty, Henrik's problem is serious and he should take his camera to Canon immediately.

I am going to call Canon in an hour and see what they are going to do.

I just got of the phone with Canon. The camera has 12 months of warranty but in the second year they do not charge you. I guess this has to do with the powerful European Union laws that do not accept 12 months of warranty on expensive electronic devices. So I am going to ship my camera to Canon and see what they are going to do about the problem.

I will keep everyone update on the progress. Probably takes a few weeks. Ouch. But I am more then happy that they are going to fix it.

Floris, as far as I remember the EU Law is actually 2 years of warranty
not the usual 1 years most shops advertise.

I spoke to Canon this morning who (and with due respect) told me to take
it to Mediamarkt. Almost all of the guys in MM knows less than the little
I do. However a helpful local canon dealer will send it to the Benelux
repair shop which is a technician outside of Canon in Holland. He thought
it would take several weeks to get back. Apparantly Canon do not have
their own technician and outsource their work.

Anyhow, I also now found 1 LIT pixel, looks like a shining star with a bit
of black around it but obviously the posted screen shots are quiet clear

Thanks for resting my mind that this is not normal.

Marty,

Can you post a screen shot for comparison?

Thanks.

I will have to grab my camera from home at lunch time and grab a few shots. However, I watched the footage I shot last week and can tell you that the 2 lit pixels look more like a tiny white spec of dust on the frame than "bright" spots I have seen in the past. Mind you, these are in the exact same spots as before so I am sure they are pixels and not dust. For some reason this time they look more "passive" and not so bright. I was at 0db gain so maybe that explains why they were less intense.

marty,

Would be interesting to see your shots of it. Maybe your LIT pixels
will become less noticable if you play with the iris ring.

I have my camera and will try to capture a few frames here shortly. On another weird note, I had to adjust my backfocus on the manual lens at lunch, so I had the camera hooked to a 42" LCD while performing this. When I was done, I put the lens cap on and checked for the lit pixels. None. I cranked the gain to +12. Nothing. I changed the shutter to 1/6 sec.....nothing. Okay, maybe at 1/6 I could see a spec....a teeny tiny spec in one of the areas. I was straining to see it. It would not have been visible under normal shooting conditions.

Putting it back to 3db and normal shutter speed and it is clean as....well...something that is very clean!

So I struggle with the intermittent nature of this. I will still try to grab a few frames for you.

I dropped my camera off at Canon's European repair centre today. It will take 2 to 3 weeks for them to fix this (estimation).

We'll wait and see what happens. One thing that I know for sure is that I am going to do check for this issue weekly once I get it back and while it is still under warranty. It appears that this is a common issue.

Floris,

Your camera will sit next to mine as I dropped it off on monday here
in Antwerpen. They told me that Canon here use a Company called
ETB which is Canon's repair technicians, and yes they are in Holland.

Do you know if it is the same repair center your go to?

Yes, it is ETB in Roosendaal, The Netherlands. It is like a one-hour drive from Antwerpen I think. You could pick it up there if you wanted.

Thanks Floris, I'll find them and give them a call if it takes too long.

The long wait has begun. I can check the status of my repair and it says the camera shipped to repair location and it took two days. I wonder if they shipped my camera to Canon's Repair Center in Irvin, USA. Looks like they did.

My camera was opened by a technician yesterday, closed on the same day, checked today and the case was closed as well. So I think it will be a few days until I have it back and then I will also learn what they repaired/fixed.

I am very happy that I will soon be reunited with my camera.

Good Luck Florence. Canon has always been quick to turn around cameras when I send them in. However, they are often very vague on what they actually do to the camera. I have sent 3 different cameras to them for specific problems and the paperwork returned always says something like "camera checked and returned to manufacturer specifications". Huh?

I had to call and talk to a few people and insist they get me some info before they finally told me they replaced a bad circuit board that was causing noise in the original XL1.

Did you send a detailed description of the issue and some frame grabs to guide them to the bad pixels? I would be concerned because the issue can be intermittent and the day they put it on the test bench may be a "good day" and the tech might not see anything wrong.....hope this is not the case for you.

Thanks,
Marty

Marty, I shot a reference tape while the problem was imminent and included that in the box which shipped to Canon. So they have a tape, as well as a link to a reference movie I posted on my server, which showed multiple hotpixels around my screen and I also wrote down "my CCD is infested with hot pixels. They are all over the place. Please check thoroughly." I will check the camera straight after I pick it up. If the problem is still there, the camera goes back to Canon but in that scenario I will demand a replacement camera. It takes around 2 - 3 weeks each time and it has been long enough.