Sensor moving on Epic Dragon

[Aris_Gavriilidis]

Very recently, through a friend, I heard a story from the set of Assassin's Creed, I wasn't there myself nor was I involved with the project in any way but apparently the sensors on the Epic Dragons they were using, physically moved as the cameras were tilted etc. and the image was going soft as a result. Is there any truth to this, has anyone ever noticed something like this happening? I surely haven't, at least not on my camera. It sounds really strange, it's the first time I've heard of something like this happening and I'm curious to see if it's actually a real issue with the cameras or if it just happened to be one on a few specific bodies.

 

[Phil Holland]

Moved as is somebody adjusted the Back Focus? Or moved like it's loose inside the camera?

 

[Brandon Shafto]

Sounds like he's saying it's loose. Which doesn't sound right at all.

 

[Matt Ryan]

lol this kinda sounds ridiculous. I could see image softening happen with a long heavy zoom lens without proper support and flexing the lens mount a bit when tilting. But the actual sensor moving?? Highly doubt it.

 

[Bérenger Brillante]

lol this kinda sounds ridiculous. I could see image softening happen with a long heavy zoom lens without proper support and flexing the lens mount a bit when tilting. But the actual sensor moving?? Highly doubt it.

Totally agree.
But maybe they mistake the OLPF for the sensor, and did not tighten enough the OLPF ?

 

[Aris_Gavriilidis]

As in loose inside the camera, I know it sounds ridiculous. It does seem very strange for something like this to occur, especially on a production of that scale.

 

[Tommaso Alvisi]

Unfortunately on DMSC1 bodies (and DSMC2 too) the sensor could move slightly due to vibrations (usually X and Y, not Z tho),
in fact Jarred announced a mod which will be available to have the whole sensor cage replaced with a fixed (ie non tuneable) assembly.

PRO: perfect stability, camera brain would be even lighter!!!!
CON: you loose the on the fly collimation correction

 

[Aris_Gavriilidis]

Tommaso could you provide some more info? Especially about the mod and Jarred's post, how recent was it? From what you say it looks like a pretty serious issue

 

[Daniel Stilling]

I don't know, but it sounds like a bad focus puller excuse...

 

[Zeb B]

Undocumented 6 Axis Stabilization Feature

;-)

 

[Tommaso Alvisi]

I agree with Daniel, in my experience sensor moves slightly X-Y, not on the Z axis so it would not cause any problem in the focus plane.

Just asymmetrical vignetting.

Which is pretty annoying with lenses which barely cover the targeted resolution for a certain project...it can render the lens set unusable...or the camera.

The sensor doesn't move freely during operation, it just slowly shifts due to vibrations induced to the camera (trolley are the worst offenders imho).

My Weapon MG is much much better in this regard tho.

 

[Shane Kelly]

lol this kinda sounds ridiculous. I could see image softening happen with a long heavy zoom lens without proper support and flexing the lens mount a bit when tilting. But the actual sensor moving?? Highly doubt it.

It's real.Also happened on a major network show Dp'd by a good friend of mine. Camera was tilted straight down and they were losing focus.
Red came out and fixed it . These were probably early cameras and I can't imagine that it's still a problem.

 

[Matt Ryan]

It's real.Also happened on a major network show Dp'd by a good friend of mine. Camera was tilted straight down and they were losing focus.
Red came out and fixed it . These were probably early cameras and I can't imagine that it's still a problem.

How does it pass QC? Things like that are fuel for people in the industry who already dislike RED and enough to scare others off. Not good at all...

Are you sure it's the sensor and not the olpf? I'm hoping OLPF rather than the actual sensor.

 

[Aris_Gavriilidis]

If it's real then it's outrageous that a camera of this level has such a major issue.

 

[Björn Benckert]

This is no biggy. When it happens you just tilt up towards the sky and shake the camera a bit and then all is back to normal. Lol.

 

[Zeb B]

Odd really. You would think the sensor would be laminated to a metal heat sink

 

[Aris_Gavriilidis]

Yeah I was thinking the same, with all these electronic components tightly packed in such a small body you'd think there would be a solid connection between the sensor and the rest. It's a real shame this issue exists on such a wonderful camera.

 

[Tommaso Alvisi]

Yeah I was thinking the same, with all these electronic components tightly packed in such a small body you'd think there would be a solid connection between the sensor and the rest. It's a real shame this issue exists on such a wonderful camera.

There is, but then you want to infinitely adjust back focus, right?

-> sensor is on a MOVEABLE support.

You can adjust Z (aka focal flange depth) which is very handy indeed,
but it causes a little X-Y movement too (you can see the effect of this when you set the backfocus).

It's not RED's fault, it's a matter of priorities.

RED knows it and that's why Jarred is going to offer an option to replace the sensor cage with a NON TUNEABLE, FIXED ONE.

It will be useful to aerial shooters, camera car specialists, extreme sports POV rigs, etc etc!

It would also make me very happy since I keep my lenses in tip top conditions so I rarely need setting the back focus,
but I need a perfectly centered sensor to avoid asymmetrical vignetting and loosing a step in the resolution chart...

I had to go from 6K WS to 5.5K WS in some instances or from 5.5K WS to 5K WS on some lens sets, and only because of this...

 

[Vadim Bobkovsky]

Are they even using Reds on the set of Assassin's Creed? I thought it was all Alexa 65 show.

 

[Zeb B]

What ever the issue is . . . RED will get it fixed. They always do