Film-Tech Forum ARCHIVE: approximate resolution of film

This is topic approximate resolution of film in forum The Afterlife at Film-Tech Forum ARCHIVE.

To visit this topic, use this URL:
https://ft-forum.com/ft/cgi-bin/ubb/ultimatebb.cgi?ubb=get_topic;f=12;t=000468

Posted by Mike Carro (Member # 232) on 01-29-2006, 07:02 PM:

What would be the approximate digital equivalent resolution of a frame of 35mm movie film(not still). Is it 4k X 3K approximately?
thanks

Posted by Bobby Henderson (Member # 840) on 01-29-2006, 07:30 PM:

There are differences of opinion on the matter. Some numbers suggest a 4-perf 35mm frame can display 24 million pixels of image detail. Others say a 4K video stream (4096 pixels across) would be adequate to replace 4-perf 35mm.

Most agree 2K (2048 pixels across) or HD (1920 pixels across) is not good enough to match 35mm.

Posted by Monte L Fullmer (Member # 2797) on 01-29-2006, 07:33 PM:

..probably is this why SONY is pushing to the 4K systems - to get to that 4096 resolution?

Posted by Greg Mueller (Member # 17) on 01-29-2006, 08:19 PM:

Back when all this digital hoop-lah started I read and article that said 13+ million pixels per frame

Posted by Mike Carro (Member # 232) on 01-29-2006, 11:29 PM:

Yeah Greg, I remember something like that too. I think the 24 million pixel number is for a still image of 35mm film being double the area of 4 perf frame.
I'm wondering because if you can really better the image resolution then I think that digital is a natural progression in movie making. I'm a long time film collector so I don't need convincing on how great it looks. I'm just starting to come around because I see the improvements.

Posted by Darryl Spicer (Member # 711) on 01-30-2006, 11:06 AM:

I just wonder on that digital stuff just how much is exagerated imagery. In other words if you go into an electronics store you have all the display devices set up. None of them look the same. All the settings are wacked out. You have to run a calibration program to set the set up for the best playback and then rely on the source.

Posted by Mike Carro (Member # 232) on 01-30-2006, 02:14 PM:

yeah, that's true but for the most part in looks pretty damn good. And once you get something set up in your home you wouldn't have to fuss with it that much.

Posted by John Pytlak (Member # 331) on 01-30-2006, 03:45 PM:

There's little argument that AT LEAST a 4K scan is needed to fully capture the detail in a 35mm frame. With a 4:3 aspect ratio full frame, that's approximately 12 megapixels per frame, a simplified figure that Kodak used in its ads for awhile.

In actuality, it's probably somewhat higher.

Image quality is measured by much more than resolution --- dynamic range, tonality, color reproduction, archivability, lack of aliasing, etc. all still favor film.

Posted by Joe Redifer (Member # 3) on 01-30-2006, 06:53 PM:

I think video has pretty much gotten the "archivability" feature down pat since it's digital. All you have to do is make a direct digital copy every 12 or so years and you're set. The 6,000th copy is exactly like the first 72,000 years later. Digital is perfect in every way except where it's flawed.

Posted by John Pytlak (Member # 331) on 01-31-2006, 02:34 PM:

Digital is like "Ice Age" --- Migrate, or your images may be extinct. [Wink]

Trouble is, many of today's digital image formats have considerable compression, so migrating to new storage formats may be sensitive to missing the bits that are no longer there.

Posted by Michael Schaffer (Member # 1204) on 01-31-2006, 02:50 PM:

But then wouldn't or shouldn't anything considered really worth preserving, if not distributed and played back, then at least be stored in uncompressed formats? Digital images and films do take up a lot of storage space, but then the storage media are not that expensive anymore.

Posted by Greg Mueller (Member # 17) on 01-31-2006, 04:16 PM:

Imagine at 13+ meg per frame how big a file would have to be to store one movie, if it were not compressed [Eek!]

Posted by Joe Redifer (Member # 3) on 01-31-2006, 04:32 PM:

John/Greg, if you were intent on ARCHIVING something in digital, I don't think you're gonna compress it into MPEG or DIVX. And surely when the file "migrates" it's not going to be recompressed. That would be stupid. The storage mediums aren't there yet, but they will be very, very soon. I submit to you that digital data can last LONGER than film with absolutely ZERO loss from the original source.... EVER!

What are your opinions about solid state memory? No more "ice age"!

Posted by Larry Myers (Member # 738) on 01-31-2006, 05:07 PM:

Both still and motion picture film image resolution will be measured the same way. The best way is the use of MTF contrast measurements. The quick and dirty way is by the use of resolution targets. The actual measurement is in line pairs per millimeter much like a image printed in a book which is measured in dots per inch.

I would say the average is about 35 lines pairs per millimeter high contrast for a typical good quality 35mm motion picture frame. Can be as low as 15 and as high as 100.

[ 02-01-2006, 01:35 PM: Message edited by: Larry Myers ]

Posted by Greg Mueller (Member # 17) on 01-31-2006, 06:29 PM:

This might sound far fetched but would solid state memory be subject to EMF pulse or other electrical fields? Magnetic fileds?

Posted by John Pytlak (Member # 331) on 02-01-2006, 12:45 PM:

quote:
John/Greg, if you were intent on ARCHIVING something in digital, I don't think you're gonna compress it into MPEG or DIVX. And surely when the file "migrates" it's not going to be recompressed. That would be stupid. The storage mediums aren't there yet, but they will be very, very soon. I submit to you that digital data can last LONGER than film with absolutely ZERO loss from the original source.... EVER!

I was speaking in terms of the technology that is practical today, where some degree of compression is still needed to economically store the huge data files needed for a feature film.

"Film is Future Proof" in the sense that it is certain that there will be a way to transfer it to any future display medium. When decades-old movies and filmed television shows (e.g., "I Love Lucy", "Hogan's Heroes") are being scanned at 4K today for use on HD television outlets (including future HD-DVD), it was a market that was never envisioned when those shows were made. But even fifty-year-old film has the image quality to meet the needs of the most sophisticated electronic display technologies today, and tomorrow.

At ShowEast, when Sony wanted to show the capabilities of their 4K SXRD Digital Cinema Projector, they used filmed scenes from "The Music Man" (8-perf 35mm film) and "The Sound of Music" (65mm film), which had much better sharpness than the clips from Star Wars Episode 3 in the same demo.