Posted by on Aug 15, 2012

Short time ago I got a message from some Multimedia-Art Master Students from Salzburg. They were searching for a DIT/Data Wrangler for their Project “Back tot he Roots“, a Sci fi short shot with the Arri Alexa with some quite ambitious Vfx shots.

Fur further Infos you can get the details from their website at

Not having been on a set for a while and taking the chance of being somewhere else with new people, working on a project i jumped in and helped out for a couple of days.

First of all working with the Alexa was a joy.

There a two things in my opinion that stand out with this camera:

The Latitude / dynamic range of the camera in combination with different workflows:

The Alexa claims to have around 13,5 stops of latitude, which is quite impressive. Furthermore you can choose which route to go either for ease of workflow using Prores 422 in Rec709 color space, or you go up higher shooting Prores 4444 using Log C in order to get more Information out of your footage to work with. This was the option they chose.

I was checking some footage while shooting and one thing was a bit surprising to me:

There´s a handy tool available online called the “Arri Lut Generator”

Because the footage is encoded in Log C you need a proper Lookup table (Lut) (basically a Lut is a Transformation Matrix that changes input values to a mostly different output value) so that you can view your image in a proper way. Otherwise the footage looks flat, somehow unsaturated, like a logarithic film scan.

They provide a 1d Lut (kind of a simpler kind of transformation, more of a gamma change) for on set preview and this gives a satisfying result.

I also tried the proper 3d Lut (where each RGB value is changed in a different way, giving a more sophisticated transformation). Strangely for my eye the material then looked wrong, contrast was good, but I found it to have heavily oversaturated Yellows and Blues. Nothing that could not be corrected, but definitely worse than the Preview I got from the simple 1d Lut. I did not have time to look into that more deeply, but this was not was I would have expected.

Besides the latitude the camera you can clearly see that it was developed by a company who has years of experience working with sturdy, analogue cameras and they were able to transfer these qualities onto their new camera.

First of all it´s heavy and compact, not overly complicated, but you got everything you need and easy to reach.

What struck me most was not the output of the camera itself, but compared to a standard Canon Dslr I found that you automatically treat the Alexa in a different way, because the way it´s built. Even if you can mount most of the additional Equipment like filters, matte boxes, rods etc. it sometimes feels like a clumsy workaround solution. With the Alexa being built as a true movie camera, you´ll find most of the things where you expect them and I found that automatically somehow Cameraman and Assistant take more time to do things right, which might not be as fast, but those tiny bits and peaces add up and finally I think it will be visible in the end result.

Shooting is still going on and i´ll probably be working on some of the Vfx shots, so i´ll keep you updated.

Here are some impressions from the set, some taking by me, others marked with the logo were taking from other crew members.