Dragon Sensor - possible dead/hot pixel - Need help

[Stian Eriksen]

Hi Everybody!

We've got a little issue with our Epic Dragon.
We upgraded from Epic to Dragon in the last open upgrade window(when RED announced Weapon) so it's been a year and a bit.
Now we've found what appears to be a dead/hot pixel or something on our sensor. I have cleaned the OLPFs properly and they seem absolutely fine.
The spot is in the same place when I change between OLPFs so I'm thinking this is on the actual sensor. I've tried to blow carefully with a blower holding the camera mount down to no avail. I've done firmware upgrades and also calibrated the black shade a lot of times!

What do you guys think this is? I've never encountered a dead/hot pixel on our cameras before so I'm not sure what are the telltale signs.
When zooming in to the image in post I see that it's a cluster of spots. Almost like a cluster of stars in the sky at night. The spot looks pink with the skin tone OLPF and more grey with the low light OLPF.

I've been in contact with Red, but they can't give a diagnosis based on the material I've given them. That's why I thought I'd try it out on the community.
They've told me that the worst case scenario is that the sensor needs to be replaced at 10 000 EUROS! The camera has never been operated without OLPF, so I'm not sure how any smudges, grease or dust could have gotten in there. When inspecting with a flashlight I can't see anything on the sensor either.

I'll attach a few images and a few downloads here so you can see for yourself.

Two very short RED trims, one with Skin tone OLPF and one with Low light OLPF: https://we.tl/j6ZRCFlTsY

The zoomed in image shows the "splotches". There's two clusters as you can see.
The other image shows the location in e few frames.

if anyone can help me with this I would appreciate it a lot!
Let me know if you need anything else from me. I could run custom tests if you have any idea what to do.

Thanks!

Stian Eriksen

 

[Hal Long]

It does look like it may be pixel issue a group of pixels. Have you shot concerts or any projects around lasers? You have black shaded properly? If so, you might want to send it in to Red.

 

[Stacey Spears]

Just to make sure, you have done a black shade? I once had a red pixel that showed up one day on my EPIC Dragon. I did a black shade and it was gone.

 

[Serge Polevitzky]

Stian -- these are some long shots, but your other possibilities include a trip to RED for 10K Euros -- so why not give these a try ?

(1) Try removing the OLPF & filming a blank white target with a good, even light. You'll probably wind up focusing the lens at Infinity, but you'll only be able to get the target
to be in focus at about 9 feet or so (the OLPF shifts the plane of focus). This should tell you what the sensor alone actually sees. If there is nothing in these images, then your
OLPF or OLPFs may be suspect. Also, get a bright light at an angle & a good loupe & look at the sensor and OLPF(s) ... both sides of the OLPFs.

(2) Have you ever used either the PL or Canon Motion Mount ? Reason I ask is that I think they both have a rubber gasket (Canon does for sure) & a tiny bit of the rubber
gasket could have fallen off & into the camera cavity. When you changed OLPFs, that little bit of rubber gasket could have gotten dislodged & hit the sensor. OK, this is a really
remote possibility -- but if true -- or if something like this happened -- a gel stick could reduce that 10K Euro trip to RED to maybe a $40 gel stick fix.

(3) If using the Canon or PL Motion Mount, check it for debris.

(4) What would RED charge to clean the camera -- totally clean it, especially the sensor ?

Best of luck & let us all know how this worked out (so we can learn ...)
Serge
"Learning is not compulsory ... neither is survival !"
-- W. Edwards Deming

Hi Everybody!

We've got a little issue with our Epic Dragon.
We upgraded from Epic to Dragon in the last open upgrade window(when RED announced Weapon) so it's been a year and a bit.
Now we've found what appears to be a dead/hot pixel or something on our sensor. I have cleaned the OLPFs properly and they seem absolutely fine.
The spot is in the same place when I change between OLPFs so I'm thinking this is on the actual sensor. I've tried to blow carefully with a blower holding the camera mount down to no avail. I've done firmware upgrades and also calibrated the black shade a lot of times!

What do you guys think this is? I've never encountered a dead/hot pixel on our cameras before so I'm not sure what are the telltale signs.
When zooming in to the image in post I see that it's a cluster of spots. Almost like a cluster of stars in the sky at night. The spot looks pink with the skin tone OLPF and more grey with the low light OLPF.

I've been in contact with Red, but they can't give a diagnosis based on the material I've given them. That's why I thought I'd try it out on the community.
They've told me that the worst case scenario is that the sensor needs to be replaced at 10 000 EUROS! The camera has never been operated without OLPF, so I'm not sure how any smudges, grease or dust could have gotten in there. When inspecting with a flashlight I can't see anything on the sensor either.

I'll attach a few images and a few downloads here so you can see for yourself.

Two very short RED trims, one with Skin tone OLPF and one with Low light OLPF: https://we.tl/j6ZRCFlTsY

The zoomed in image shows the "splotches". There's two clusters as you can see.
The other image shows the location in e few frames.

if anyone can help me with this I would appreciate it a lot!
Let me know if you need anything else from me. I could run custom tests if you have any idea what to do.

Thanks!

Stian Eriksen

 

[Stian Eriksen]

Hi Everybody.

Thanks for your replies.

I've just updated to the newest firmware (v6.3.27). And also done many black shades without it helping.
We've shot around lasers after this appeared, but not before to my knowledge.

Serge:

I did a quick test shoot on a bright even surface. I did 6 shots. 2 with skin tone OLPF, 2 with low light OLPF and 2 without any OLPF.
Each test is done at 2 different t-stops to see if it changed anything, the first at T2.8 and 1/400 sec shutter and the other at T8 and 1/50 sec shutter.
The cluster is visible in all the shots, but they do change a little bit when changing OLPF.
The OLPFs look completely clean, and the sensor looks clean as well.

I've attached full res JPEG in this post. Please, download them and inspect them if you think it can help give a diagnosis.

We haven't used the motion mount at all on this camera.

I guess we have to send it in for a service and a proper diagnosis. This kind of suck as the sensor is 1'ish year old, and a replacement is super expensive.
We'll see what they say. I'll let you guys know what happens.

Off topic: Can anyone explain to me what happens in the OLPF? When not using the OLPF I could not pull focus past 2-3 meters (6-9 feet) even though my lens was on infinity. Just curious

Thanks again.
Stian

 

[Stian Eriksen]

I could only do 5 attachments. Here are the 2 missing jpgs.
These are No OLPF.

Stian

 

[Serge Polevitzky]

Stian -- I have an Mg Weapon (with the same kind of Dragon sensor as yours). With no OLPF in the camera, with a lens focused at Infinity, subjects at 9 feet or so will be in focus. That's as far as
I can get the lens to focus. Seems to be the same thing you have found. Somewhat understandable as the OLPF adds to the light path and "has to" change the focal point versus without an OLPF
installed.

As to the very small 'junk' on the images (both with and without any OLPF mounted), whatever is causing the 'junk' to appear probably is quite small. So there is the remote possibility that
some extremely small bit of dust or grit may have gotten on to the sensor. If this is the case, then the sensor might be 'rescued' -- either by a cleaning by RED (probably not cheap, but
if you are [relatively] lucky, the bill from RED for cleaning will be much less than the 10K Euro sensor replacement cost). Or you might also consider buying a gel stick or two at $40 each.

It's a guess, but the gel stick method could well be what RED would use. The gel stick is at least something to consider.

Also a guess, even under a bright light with a good loupe, if there is in fact something extremely small on the sensor, seeing it may be next to impossible. So if you don't see something, this
doesn't necessarily mean that some extremely small bit of junk isn't there.

Super cautious path forward: send the camera to RED and ask them to evaluate. Ask for the cost for the best cleaning they can do (not just the sensor, clean the entire camera). They may be able to
fix the problem without the 'total cleaning.' If they don't have an obvious fix, if the cost of cleaning isn't too bad, ask them to do a super-cleaning, and if that fixes it, fine. If the junk still appears,
then, when & how did you pay for the camera ? If with an AMEX card, AMEX may have extended the warranty by 1 year. If the junk is not due to normal use & exposure to normal dust & grit, between
AMEX & RED you may have some relief.

If you decide to try the gel stick yourself, this might negate RED or AMEX helping, as it would raise the possibility that you accidentally damaged the sensor while trying to clean it. So there could be
risk in the self-administered gel stick attempt.

My 2 ¢ ... Good luck & let us know what happens.
Serge

I could only do 5 attachments. Here are the 2 missing jpgs.
These are No OLPF.

Stian