Helium & Gemini Colour Matching / CHARMCINE Test

[James Miller 72]

Using CHARMCINE test 3200 ISO R3D frames https://vimeo.com/263222229 copyright to them.

I changed the Gemini to sit at ISO 2000, relative exposure ISO 4000 on Helium and ISO 5000 on Dragon. Reading the description they adjusted Key to match exposure on Dragon but looked like its stayed the same on Helium & Gemini. Only matching Helium and Gemini here as the Dragon was Epic-X body.

Tweaked in RCX then changed (matrix only) to be more inline with ARRI from test, then colour corrected. There are drifts but wanted to see how much I could adjust Helium to match.

Set all to DC2/RG4 as a middle ground without using IPP2

D.E.B not used in RCX due to green cast in neutral. I used Resolve, Spatial Threshold Chroma only at 15.0 to remove colour noise. LUT applied in Resolve with Tetrahedral conversion. Output at 1080.

R3D, TIFFs pre and after Resolve.
LUTs used.
https://we.tl/eaCLBAoljn

 

[rand thompson]

James,

Thanks a lot for doing these test and your experimenting with different color matrices!

 

[Nino Tamburri]

I see the Green cast in the shadows of the Helium sensor is a common thing, my Helium has always shown this colour shift. Youd think Red would just permanently fix this.

 

[AndreasOberg]

Good to see. I would say that I prefer the Gemini colors in this image. The green always worried me a bit with Helium.

/Andreas

 

[Reuben Evans]

Is that just a normal tungsten bulb in the background? In my experience normal bulbs like that can still have a green spike. It may be that Helium is seeing green where Gemini isn't, due to sensitivity, rather than skewing mids/shadows green.

 

[rand thompson]

with a little less green.

 

[Brent G Miller Jr]

Did these tests keep the Gemini in normal mode or was it changed to LL mode at some point?

 

[Curtis boggs]

It looks like to me that you've proven that Helium can do high ISO just fine,
unless I'm missing something.

Helium is slightly more sensitive to green but that's fairly easy to handle.

Curtis

 

[Reuben Evans]

When I take a close look, I actually prefer the helium's picture.

 

[rand thompson]

Higher contrast , closer to grey walls.

[/url]Helium_r3d_3200.R3D.0000085F_S001.0000000 2 by rand thompson, on Flickr[/IMG]

 

[Jason beaumont]

alexa looks awesome, gemini looks awesome. helium looks like shrek.

 

[rand thompson]

Grade out of Redcine-X Pro

https://www.dropbox.com/s/grpkmwyhke7rvmt/Guy with chart.RMD?dl=0

[/url]Helium_r3d_3200.R3D.0000085F by rand thompson, on Flickr[/IMG]

 

[Michael Wahba]

Helium seems to fall apart at this ISO. Still a tough decision to decide on Gemini vs Helium though.

 

[rand thompson]

Michael,


This grade was actually 4000 iso and I further lifted the shadows. So hopefully you didn't base your opinion of Helium's capabilities on this grade above but from somewhere else or from your own testing.