John Shell

The entire short film is available on Vimeo for free

I remember reading somewhere several years back about how the CRT film recorders IMAX uses are limited to 4K because of the spot size and I’m just wondering, is it still the case today ?? And why can’t they use laser recorders for higher resolution ??

On 10/25/2023 at 8:32 AM, Stephen Perera said:

that thing digital has....

Which thing ??

The colorist(Yvan Lucas) mentioned on his Instagram that he used an Autochrome LUT, a 3 strip technicolor process for the last scene and a classic bleach bypass for some other scenes

I've been hearing about the Alexa looking film like or closest to film and I just don't see it. Unless it has undergone obvious film emulation, every movie I've seen shot on an Arri Alexa looks digital just like any other movie shot on a RED or a Venice. Take the Marvel films for example, most are primarily shot on an Arri Alexa and they look nothing like film. 

On 2/25/2015 at 2:20 AM, Carl Looper said:

 

Yes, I've proposed the same thing in the past. Jitter the sensor. And resample (or jitter the projector - great idea). But as your experiment demonstrates it's still not quite ideal.

 

But it can be improved without ending up back with film.

 

If the sensor cells are randomly arranged in a fashion similar to an organic retina, this should have the effect of neutralising any global correlations that might interfere with image perception.

 

So a sensor that looks like this (a monkey retina), and peizo jittered. And the projector performing the inverse jitter (great idea), or the data can otherwise be re-sampled for a regular grid projector.

 

http://imgc.allpostersimages.com/images/P-473-488-90/72/7273/M3KT100Z/posters/sinclair-stammers-light-micrograph-of-monkey-retina-high-power.jpg

Dunno if it's the same as jittering but the Pentax K-3 dslr had a feature where the sensor gets micro vibrated at a rate of 500hz to produce some blur. This was their method of reducing aliasing without using an anti aliasing filter. Not sure if any other cameras ever had this feature tho

On 7/31/2023 at 6:04 AM, Kemalettin Sert said:

There s no chance 65mm 15perf resolves 18K details.Technically impossible i would say.

50MP Venice 2 is almost 2 times sharper than 65mm Vision negative which was shot on medium format camera and used same pentax lenses on both cameras.

It would be fair comparing 4x5 film against todays digital cameras.I shoot 4x5 a lot 100 ISO mostly and they are not even sharper than my GFX 100s.

Any chance you could share some of the images you've shot. and compared??.

On 7/24/2023 at 6:33 AM, Scott Pickering said:

I certainly don’t see how IMAX can be 18K rez, after view IMAX film again today. I think 8K would give it a run for its money.

That 18K figure has always been dubious especially when Yedlin showed in his ResDemo that IMAX 70mm Vision 3 500T scanned at 11K resolved slightly less detail than Alexa 65 with 6.5K resolution. Vision 3 50D would be a lot more resolute but still nowhere near 18K. Also, I I doubt those old medium format lenses could even get near that.

@Tyler PurcellAre you sure Tenet was a DI finish ? 

One of the reasons stated by DoP Greig Fraser as to why they decided not to shoot Dune on film was because it looked too nostalgic and I’m just wondering, is this really a valid reason considering all the tools available today in digital imaging which can create basically any look you want ?? Also there are several movies shot on film that look very modern.

Forgive me but I’m still confused about this camera’s sensor. How exactly does this camera not perform any demosaicing when each photosite only gets 1 color just like a Bayer sensor ?? 

Reading through various forums, I always see people talk about the filmic colours on their old CCD stills camera and older cinema cameras like the Sony F35 having a filmic look and I wonder if this is just some nostalgia nonsense or there's some truth to it?? 

On 9/21/2021 at 1:37 PM, Stephen Perera said:

come on, even the 'Red' cameras look more like film any day of the week than Alexa's) 

Please tell me you're joking

So I was reading an old article from Kodak on Mission Impossible: Ghost protocol and they mentioned:

"The IMAX material was shot with the 15-perf IMAX camera, as well as the smaller, lighter 8-perf Iwerks camera for shots involving more camera movement or Steadicam. Hasselblad lenses were used. Elswit gravitated toward wider focal lengths—40mm, 50mm, 60mm and 80mm for IMAX—in order to fill the large-format frame with visual information. “If there is one weak element in IMAX, it’s these 30-year-old lenses,” Elswit notes. “They’re OK, just not great.”

https://web.archive.org/web/20120129035501/http://motion.kodak.com/motion/Publications/In_Camera/Focus_on_Film/missionImpossible.htm

I'm guessing he's referring to sharpness here but are old haselblad medium format lenses really not that good in sharpness ?? Or could be be referring to something else ??

Not that I think bigger sensors are better but I'm just wondering, the ALEXA 65 is about a decade old now it still remains the only cinema camera in this segment(well there was the Phantom 65 but it's retired now and never really gained much traction anyway). I'm aware of issues of manufacturing larger sensors but even IMAX is building new 15/65 film cameras in this digital age and I'm not sure those are cheaper to make. 

On 1/28/2023 at 12:35 AM, Scott Shepley said:

 

 

Looks like an IMAX Mark II camera built by Jeff Williamson. 

I googled Jeff Williamson and strangely couldn't find anything at all. Anyway, were the IMAX Mark III and Mark IV also built by him ?? 

On 4/29/2020 at 7:11 PM, David Mullen ASC said:

I could definitely be mistaken, but I thought I heard that the 3D IMAX film "Wings of Courage" was shot on Fuji 65mm film. 

It was and Fuji supplied the film for free. This info is from ascmag 08/1995

On 2/14/2021 at 2:15 PM, David Mullen ASC said:

65mm 15-Perf (Imax) 
1.34:1    Camera Full Aperture            2.772" x 2.072"        70.41mm x 52.63mm
1.43:1    Projector Aperture            2.740" x 1.909"        69.6mm x 48.5mm

Does the camera aperture equal the exposed area on the negative ??  Meaning that IMAX true aspect ratio is 1.34:1 and not 1.43:1 like everyone says ??

Also, what is the need for masking(or let's say cropping) such a small portion for projection ??

Thanks

On 9/14/2022 at 4:58 PM, David Mullen ASC said:

Sure, I think John Galt at Panavision might have once been working on a 4K version of the Genesis, maybe with a full-frame sensor -- I think the original Primo 70 lenses were developed for that. Just a rumor though.

Interesting. Another thing, what does RGB stripes or striped sensor mean exactly ?? Is it just a Colour Filter Array with RGB lines stripes in that order or does the sensor itself have stripes or something?? I tried googling to see what it looks like or an illustration but I couldn't find anything.

On 7/5/2018 at 1:03 AM, David Mullen ASC said:

Its not a Bayer CFA sensor, it has RGB stripes, an equal number of total photosites for each color unlike with a Bayer. So to create 1920 x 1080 RGB, it has about 2MP per color so 6MP total. But because its not a mosaic color array pattern, you cant intelligently reconstruct a full color image at a higher resolution than 1920 x 1080 per color. Plus there is some greater tendency towards moire with this striped system.

 

But since a Bayer CFA only allots 25% of the photosites for red and blue information, Id suspect one could uprez the F35 signal fairly well at least in terms of detail in the red and blue channels.

Do you think a 4K or 8K camera with this RGB stripe sensor technique would be feasible ?? The photosite density would be very high of course but I'm just wondering 

From what I've read, the DMR process involves degraining/denoising the footage, increasing sharpness and applying edge as well as boosting contrast. I dont know about digitally shot movies but for 35mm, the main reason for degraining was 35mm grain would look very enlarged and overwhelming on an IMAX screen which kinda makes sense, as true IMAX is clean with much less visible grain. But doesn't all this come at a cost to picture quality ??

On 12/26/2021 at 10:03 AM, Tyler Purcell said:

I mean, even the Alexa 65 doesn't get remotely close to the resolution of standard 5 perf 65mm negative. 

Considering the Alexa 65 resolved more detail than IMAX film(scanned at 11K) in Yedlin's resolution demo test, I strongly doubt this statement.