digital cinematography

3D Production Terms

Happened across this amazing collection of terms (on Definition Magazine compiled by Phil Streather) that get tossed around during a stereoscopic production. Confidingly, I have not known the true definition of some, so I’m posting this cheat-sheet for myself and others to see.

BIOLOGY

BINOCULAR VISION
A vision system that utilises a pair of forward looking eyes. Humans have this, enabling them to judge distance.
BINOCULAR DISPARITY
The difference between the view from the left and right eyes.
STEREOPSIS
The ability to perceive in a third dimension, to have a depth sense. A by-product of Binocular Disparity.
HUMAN INTEROCULAR
The interpupiliary distance in humans; approximately 2” in children and 2.5” in adults.

ACQUISITION

CAMERA INTEROCULAR
The distance between the centres of the two lenses used in any 3-D filming set up (sometimes referred to as Interaxial).
STEREO PAIR OF CAMERAS
Two vertically aligned cameras, in either a Side by Side Rig or a Mirror/Beam-splitter Rig.
SIDE BY SIDE RIG
Two cameras placed side by side, able to achieve (at least) a minimum distance between the centres of the two lenses of around 2.5” -the average adult human Interocular.
MIRROR OR BEAM-SPLITTER RIG
Two cameras one looking forward through a 45º half silvered mirror and the other looking up or down for 50pc of the reflected light from the same mirror. Required if Interoculars of less than the approx. 2.5” of the Side by Side Rigs are needed. Mirror Rigs can go down to zero Interocular by moving one of the cameras on a motorised platform. Normally a stop of light is lost in the process.
STEREOGRAPHER
Can also be the DoP. Person with mathematical or intuitive knowledge of the 3-D process. In particular, the interactive relationship between Convergence and Interocular. Most often Stereographers use a spreadsheet to determine where an object will appear on the Z Axis given the focal length of lens, distance of object from camera, amount of Camera Convergence, amount of Camera Interocular and the theatre geometry.

There’s more.  Click to go on:

(more…)


What what!?!?

TAMPER is tampering with my brain…


Anamorphic playground

Things are about to get real serious around here. Wider than my ass serious…
IMG_0991upload


Iscorama : Day one

WARNING : LENS NERD CONTENT ALERT
Some early test shots with the new (to me… despite being highly sought after and damn near impossible to find) Iscorama 50. It’s also known as the Iscorama 36, as you can remove the front anamorphic adapter from the m42 nodal lens mount, and attach it to any 49mm ring. Problem is there is a large rear flange so need a deeply recessed front element 50mm focal length lens to put it on. A Nikkor 50/1.8 does the trick but it is such a cheap plastic lens that it shifts a little during the front Isco adapter’s focusing. So I’ll probably be replacing that with a more robust lens soon.

One other little bit, the DOF of the Isco is insanely deep. The out of focus areas can be pushed with a diopter (also called a close up filter). I’ve only got a +1, right now which is allowing for focus of about 2-6 feet. I really need to find a 72mm +.5 diopter, but so far no one seems to make one. Holler at me if you know where I can find one.

Anyway here is my test to see if the hunt was worth it. To have comparison footage, I threw a Nikon 28/2.8 on there to replicate the FOV that you get after un-stretching the anamorphic footage. I only did one side by side shot, and I’ll do more elaborate tests later. This was just the night after receiving the lens. So guess which shots are the Isco anamorphic mounted to a 50mm and which shots are just a 28mm with a letterbox crop. If you can’t guess then maybe the price of the Iscorama’s might drop a little:

Iscorama Day one tests from nortega on Vimeo.


Krasnogorsk-3 shoulder mount mod

Thought maybe some one (namely the Canon 5d mk2 owners) would want to see this. I took my old Krasnogorsk-3 shoulder mount and ground off the two small mounting tabs to the inverted hand grip. I then took a quick release tripod mount I had laying around and glued in a little no slip foam to space it out. Lock tight now. Shoulder stock is extend-able and with the Z-Finder this is probably better than the larger shoulder mount systems I’ve been operating with. At least in cramped spaces. It balances the weight of the 5D rather nicely. Shown here with an Iscorama 36 on a cheap plastic nikkor 50/1.8.

kransmount01a

kransmount02a

It’s my CCCP tactical shooter.


Helios 40-2 : 85/1.5

Whoa, I’d make sweaty, sticky love to this lens if I could.

Helios 40-2 from nortega on Vimeo.


three m42 lenses in one motion test

Ok, here’s a three in one (with anamorphic bonus):

Motion test : Super-Tak 1.9/85, 2/55, & CZJ 2/50 from nortega on Vimeo.

Carl Zeiss aus Jena : Pancolar 2/50
Super-Takumar 1.9/85 & AG-LA7200 Anamorphic adapter
Super-Takumar 1.9/85
Super-Takumar 2/55

All shot as flat as possible (unlike last test) with no color correct to help spot CA problems, which is painfully obvious with the Panasonic anamorphic attachment. So somebody sell me a damn Iscorama already.

Also didn’t use a steady rig this time and these are tiny lenses so there’s shake, and the reasoning behind the bizarre counting stations audio is left up to your own imagination.

End result is I think these all achieve a similar balance to the look. The Pancolar has a little more separation between the foreground and background plane to me, but I think I like the Super-Taks better… still thinking.

Test stills (color corrected):

CZJ_pan2_50

Super_TAK2_55


Carl Zeiss Biotar 1:2 58mm

Biotaron5d1Biotaron5d2

Since I don’t have a Helios 40-2 yet, thought I’d try out the new to me Biotar I just got, and it seems to craft a moving, painterly bokeh. This tiny pinky toe of a lens also has 18 blades in the iris. Crazy right!?!

It’s like shooing through 12 Promist filters with this old lens… a ton of diffusion.

Biotar Test from nortega on Vimeo.

And here are some stills (no color correction) for study:

Biotarstill02

Biotarstill01


I’ll buy your steadicam for 25 bucks

steadicam‘Cause you won’t need it after you

watch this shit!

John Hack @ Adobe writes: Adobe researchers Hailin Jin and Aseem Agarwala*, collaborating with U.Wisconsin prof. Michael Gleicher & Feng Liu, have unveiled their work on “Content-Preserving Warps for 3D Video Stabilization.” In other words, their tech can give your (and my) crappy hand-held footage the look of a Steadicam shot.

Check out the demonstration video, shot at & around Adobe’s Seattle office. It compares the new technique to what’s available in iMovie ’09 and other commercial tools.


Lego Follow Focus

legos1
Aw, hell yeah! Build your own instructions here (but only in Japanese bitches). Just remember to glue it together, because Image Stabilizers only work on the way down to the ground…

legos2 Oh snap (togehter)! An updated design & plan available here.

And video of it in action:

DIY LEGO FOLLOW FOCUS ver. 2 from RYO on Vimeo.