JVC HD Series dead pixels?!....

[Alex Dunn]

I've been shooting with my HD110 for 18 months and just now had two pixels blow at once. Can someone elaborate on the "limited number of times" we can run the "fix".

And, how much does JVC charge for service (cleaning tune-up vs. CCD replacement).

[Stuart Campbell]

Referring to my earlier post in this thread;

"With the JVC hd pixel comp facility you can correct up to 127 errors with composite video levels of 50mV or more. There is no limit to the number of errors on any single line within your 127. However, the maximum consecutive errors are 4 and results may end up being worse than single correction so watch out."

The likely hood of you reaching these limits is extremely unlikely! That's a hell of a lot of dead pixels and if you are getting that many then you have some other underlying fault.

No need for JVC to service it to get pixels sorted out. If you are talking about a general service you'd do no worse than contacting your local broadcast kit dealer who will probably have an in house engineer to carry out your service or know of another reputable service agent. This is, of course, should your unit be out of warranty.

[John Vincent]

Originally Posted by Stuart Campbell

John,

With the JVC hd pixel comp facility you can correct up to 127 errors with composite video levels of 50mV or more. There is no limit to the number of errors on any single line within your 127. However, the maximum consecutive errors are 4 and results may end up being worse than single correction so watch out.

Thanks for that! The amount of times was unknown for a long time...

This is a real limitation on this cam, unfortunately. Here's why - if you do two feature in a row, you're looking at easily 30-40 masks. Four features? That'd be very close to maxing it out.

john

[Mark Silva]

Originally Posted by John Vincent

This is a real limitation on this cam, unfortunately. Here's why - if you do two feature in a row, you're looking at easily 30-40 masks. Four features? That'd be very close to maxing it out.

john

why would you mask 30-40 times for anything?

I've had to mask mine maybe 5 times in the last 3 years.

I would never mask just for the sake of masking....that's a waste
and not recommended at all.

[Jim Boda]

Originally Posted by Jason McCormy

Hmm. So aiming the camera on a dark object would be a way to see it?

I have to say, the companies previous camera's were Sony's and they never seemed to need tweaking like this. The S270u we bought seems bullet proof in comparison. I do like the JVC a lot though, and the images are SPECTACULAR, I just get really nervous with everything that seems to go wrong with it.

The correct process for finding dead pixels is to let the camera warm up for a couple of hours and turn the gain up (+9 or whatever). You can find the dead pixels right away with the gain up and then try to see if they are visible at a normal gain and iris level.

It helps to have a nice monitor to look at...crank the contrast and boost the brightness a little.

All camera's get dead pixels...yet, some camera's seem to have greater problems. I recently checked 4 Sony D-30's at the shop to check for dead pixels (set it to HYPER-gain and iris closed) and all the cameras had dead pixels. One camera had an exessive amount (11). And that camera's dead pixels were only visible when you boost the gain above 0 (+6 or +9). The other 3 camera's had dead pixels but they were not visible even at +9.

Camera's w/ larger chips and better light levels tend not to reveal the dead pixel that is there.

[Claude Mangold]

One instance of dead pixels here since I own the GY-HD251 (I've also exerienced it one with a 110). The only two reliable ways to check are aiming the cam at a dark background or with lens cap on and a) view with a HD monitor b) if you have a HDD, record a HD quicktime then transfer and check it on your PC. When you're shooting, you should check this every day.

Most HD cameras develop dead pixels. The last instance I know of was with a Sony XDCAM HD owned by an acquaintance.
But just contrast the relative risks of dead pixels against all that can go wrong on 16mm or 35mm film: must be 1:100 !

[John Vincent]

Originally Posted by Mark Silva

why would you mask 30-40 times for anything?

I've had to mask mine maybe 5 times in the last 3 years.

I would never mask just for the sake of masking....that's a waste
and not recommended at all.

We've had to mask a least 20 times for dead pixels - we're not doing it for fun!

And somethings those little buggers just don't want to go away, even if the camera is warmed up, even is you jack up the gain, etc - they just stay there... Until finally they are gone, for reasons that are mysterious to me.

Now this is for a full length feature, shot largely in dark situations, but they do seem to occur more with this cam than other cams...

Is there a link to a white paper or official JVC stance on this issue?

john

[Bill Brock]

I found some dead pixels and followed your instructions, but had to select camera1 in the advanced menu, then it skips over pixel compensation...it won't let me select it. Any ideas on how to get it to work? Thanks! I have the HD100(A)

[Tim Dashwood]

Originally Posted by Bill Brock

I found some dead pixels and followed your instructions, but had to select camera1 in the advanced menu, then it skips over pixel compensation...it won't let me select it. Any ideas on how to get it to work? Thanks! I have the HD100(A)

You have to be in HDV-24P mode.

[Bill Brock]

Originally Posted by Tim Dashwood

You have to be in HDV-24P mode.

Great! That worked! Thank you!

[Eric Deyerler]

To see the dead pixel you can also use the "Focus Assist"-function, so you can see the
defect/dead pixels hightlighted with a colour.

[Jeffrey Butler]

A timely discovery of this thread, as I just scored my first dead pixi or two.

[John Vincent]

Originally Posted by Mark Silva

why would you mask 30-40 times for anything?

I've had to mask mine maybe 5 times in the last 3 years.

I would never mask just for the sake of masking....that's a waste
and not recommended at all.

Shoot a feature on it - you'll be masking at least 20-30 times at least.

john

[Gibran Jimenez]

Originally Posted by Tim Dashwood

You have to be in HDV-24P mode.

Hi Tim , I have tried to do the pixel comp.. hold down focus assist + user 3+ status for 3 seconds.. nothing just goes to the regular menu screen..

I'm on 24 p mode and have it on stand by... user 3 button is assigned to nonne..

it says A at the end of the serial #.. i have the hd 100 u..

i can see the dead pixels when shooting hd only..
thanks please help

[Jeff Cerar]

Gibran,

Too many buttons....just hold down the two... "focus assist" and "menu/status" for 5 seconds.

Good luck.