The challenge of exposing the Helium sensor

[Kenneth C Merrill]

Is the difference in metering caused by Dagon Colour Science on a Helium sensor?

When Helium CS (& IPP2) is released, it may well be this Anomaly evaporates.

AJ

I hope so. I guess I was under the impression that there won't be any color science specifically for Helium since they seem to be moving toward developing images from all the sensors through the new IPP2. Seems like optimizing that process for Helium would mean messing with the results for Dragon/MX.

 

[Jacek Zakowicz]

I think it is for Helium specifically as per this article. Good news ;-)
http://www.postmagazine.com/Press-C...introduces-image-processing-enhancements.aspx

 

[David Battistella]

Seems like optimizing that process for Helium would mean messing with the results for Dragon/MX.

I think that is a pretty big assumption. It might be more like, make the helium as great as it can be without affecting legacy almost ten years of r3d color science. There is a slight responsibility to the past as people do maintain archives, stock footage, etc. every color science improvement by RED has always made older r3d better as well, (as it should be IMHO)

David

 

[David Battistella]

Is the difference in metering caused by Dagon Colour Science on a Helium sensor?

When Helium CS (& IPP2) is released, it may well be this Anomaly evaporates.

AJ

I'm only speaking to dragon and MX both of which rate very well at 320.

 

[Hrvoje Simic]

Regarding the topic of the thread and the main point of the discussion, not the ISO discrepancy, which has nothing to do with the problematic image from the first post, before discussing the solution I propose first pin-pointing the issue and removing the variables out of the equation.

- Problematic r3d grab, scene lit by Sun, plasma, HMI or tungsten with colour checked state of lamps.
- No LED, CCFL, street/stage/club/working lights.
- No NDs, no Motion Mount,
- Black-shaded camera.
- Noted OLPF and lens.

Without that, this is all speculation, generalization and talking about "something".

 

[Jose Espinosa]

What you're ignoring here is that the Dragon screen capture in the OP was shot under the exact same conditions (presumably), and it shows none of the green shift that the Helium does. So that would at least eliminate most of the external variables because it reveals that the scene isn't actually green, just the way the Helium is capturing it. As far as I can think, the only variables in capture and post would be black shade and the raw processing. You'll likely chalk it up to one of those, but since I've seen green shadows in other tests (and my own footage, when properly blackshaded), I'm not satisfied that that is the answer.

At face value you can't deny that it looks like the Dragon is capturing the scene accurately while the Helium is not. I mean, come on.

This.

 

[Josiah Duncan]

I asked earlier if anyone saw a significant difference between manual and auto blackshade on helium, so I did a quick and dirty non-scientific test today for about 10 minutes while packing up for a gig. Glad I did this, as I think based on these results I'll be running manual blackshading for everything except for run and gun from now on until auto BS is fixed. Check this out.

Epic-W helium 8k, No filtration, all daylight through a window, 1/48th shutter, only thing changing is f-stop to compensate for iso. Auto white balanced in camera to the square in the chart. To my eyes 1280iso looks similar between auto and manual, it's when you really push the iso (that's why i tested throughout the range) that you really see how green the underexposed parts of the sensor is. I want to say the Manual 6400iso image still looks a touch green, but usable as opposed to how bad the auto version is.

Please download and discuss.

https://drive.google.com/file/d/0BwQPv2ZI2E1tcnhFakxWTk9pNUU/view?usp=sharing

 

[Kenneth C Merrill]

I asked earlier if anyone saw a significant difference between manual and auto blackshade on helium, so I did a quick and dirty non-scientific test today for about 10 minutes while packing up for a gig. Glad I did this, as I think based on these results I'll be running manual blackshading for everything except for run and gun from now on until auto BS is fixed. Check this out.

Epic-W helium 8k, No filtration, all daylight through a window, 1/48th shutter, only thing changing is f-stop to compensate for iso. Auto white balanced in camera to the square in the chart. To my eyes 1280iso looks similar between auto and manual, it's when you really push the iso (that's why i tested throughout the range) that you really see how green the underexposed parts of the sensor is. I want to say the Manual 6400iso image still looks a touch green, but usable as opposed to how bad the auto version is.

Please download and discuss.

https://drive.google.com/file/d/0BwQPv2ZI2E1tcnhFakxWTk9pNUU/view?usp=sharing

Thank you for this test! I'm glad I'm not the only crazy one around here

But seriously, the green tint in the shadows is a serious issue. I hope that Graeme or someone is taking it that way.

 

[Anton Shavlik]

I asked earlier if anyone saw a significant difference between manual and auto blackshade on helium, so I did a quick and dirty non-scientific test today for about 10 minutes while packing up for a gig. Glad I did this, as I think based on these results I'll be running manual blackshading for everything except for run and gun from now on until auto BS is fixed. Check this out.

Epic-W helium 8k, No filtration, all daylight through a window, 1/48th shutter, only thing changing is f-stop to compensate for iso. Auto white balanced in camera to the square in the chart. To my eyes 1280iso looks similar between auto and manual, it's when you really push the iso (that's why i tested throughout the range) that you really see how green the underexposed parts of the sensor is. I want to say the Manual 6400iso image still looks a touch green, but usable as opposed to how bad the auto version is.

Please download and discuss.

https://drive.google.com/file/d/0BwQPv2ZI2E1tcnhFakxWTk9pNUU/view?usp=sharing

Thanks for replicating what I was seeing, glad to know I don't necessarily have a broken camera. Graeme had me send a test like this, as well as another with lens cap on with and without auto calibration as r3d stills. I would shoot him a PM and see if having the same from you might be helpful.

 

[Kenneth C Merrill]

Just wanted to revisit this with yet another link.

Comparison between Scarlet-W and Epic-W: https://www.youtube.com/watch?v=40YTGI2eihY

In the comments, the creator says, "Greener [footage] is Epic." Many other commenters also mention the green cast they've seen in Epic-W footage so far.

It's not a scientific test, but I'm not the only person seeing green.

 

[Edwin Perez]

Okay so I'm late to the party here but on my new Epic-w I'm definitely seeing the green cast too. Especially in the shadows at higher ISO's. I'm on firmware beta 6.4.21. Tried auto and manual blackshading. Are there any updates on this issue? Because it seems to be an issue since I'm reading and seeing others experiencing the same.

 

[Alex Boothby]

I asked earlier if anyone saw a significant difference between manual and auto blackshade on helium, so I did a quick and dirty non-scientific test today for about 10 minutes while packing up for a gig. Glad I did this, as I think based on these results I'll be running manual blackshading for everything except for run and gun from now on until auto BS is fixed. Check this out.

Epic-W helium 8k, No filtration, all daylight through a window, 1/48th shutter, only thing changing is f-stop to compensate for iso. Auto white balanced in camera to the square in the chart. To my eyes 1280iso looks similar between auto and manual, it's when you really push the iso (that's why i tested throughout the range) that you really see how green the underexposed parts of the sensor is. I want to say the Manual 6400iso image still looks a touch green, but usable as opposed to how bad the auto version is.

Please download and discuss.

https://drive.google.com/file/d/0BwQPv2ZI2E1tcnhFakxWTk9pNUU/view?usp=sharing

This is huge. Thanks for sharing Josiah. Any word from Red on this issue?

 

[Brendan H. Banks]

Josiah, can you share your color and gamma settings? Was this DC2/RC4?