Super 8 Resolution

[Alex]

As a brain surgeon once said in a rough time during a critical operation poceedure:
-- "Lighten up folks, this isn't Super 8 Filmmaking."

A quote from a previous post....
----------------------------------------------

Devil's advocate position...doesn't the above quote mean that Brain Surgery is EASIER than Super-8 Filmmaking...and therefore Super-8 Filmmaking can be a challenge if you are striving for a great product....and therefore....fuzzy math answers for legitimate questions can be construed as getting in the way.......

....However...perhaps John is right ...(Devil's advocate..Part Deus !).....if no one had bothered to question John's intentionally silly answer, this board would suck...but we did AND then came up with a decent answer anyway.

Alex





[This message has been edited by Alex (edited January 13, 2001).]

[Nigel]

Either way you look at it. Super8 when shot well--and shot in a way that will minimize grain, I think that it looks better than even the best HDTV cameras--Plus we can shoot slow motion!

[mattias]

you actually need 200 pixel lines to resolve 100 lines (think of trying to photograph a ladder with only as many lines as there are steps), so the "resolution" of super 8 is about 800 lines. video (sd/hd/whatever) doesn't have grain though, so the image will appear sharper at the same resolution. like carlos says, tri-x has the same resolving power as plus-x, but we all know there's a huge difference. same thing. on the other hand, film has a gradual falloff of the transfer function, meaning aliasing such as stairstepping doesn't exist, so if your image has a lot of near horizontal lines, super 8 might look sharper. not to mention the difference in contrast range between a nice kodachrome print and a video projector. see, there's so much more than resolution to this.

[#Pedro]

Carlos

Where did you find the resolution informations on the Kodak site? I?ve been searching and searching, but only found the info for VNF (80 lines/mm), nothing about K40.
Due to informations I have from an old book (late 1970) about S8, the resolution of low speed reversal color films is about 150...200 lines/mm. For S8 it would be 4.22x200=844 FOR A STILL FRAME.

But as the grain on the film is random distributed, the details of an object will be displayed by a different grain, each time the frame is going to be forwarded, similar to an eye movement. This way, the resolution of the moved film is higher than the resolution of a single frame and increases with the framerate.

If the grains were organized in a certain pattern (as on a tv screen), the resolution would keep constant, no matter if it was a still or motion picture.

With all this nice theory we should not forget, that even the highest resolution of the film itself doesn?t give us a sharp reproduction, if the focus is not accurate, if there are low cost plasic lenses involved in shooting or projecting, if the stop is not set accurate or if the camera was not hold steady or the film gate was dirty.
Pedro


[This message has been edited by #Pedro (edited January 15, 2001).]

[Alex]

Good points Pedro, Mattias, Carlos and Nigel.

The frame rate definitely adds a variable...

"Showscan" is a 65mm vista-vision format that runs at 60 frames per second...because the resolution was enhanced...

I saw a live projected demo of showscan, and it looked like higher resolution because of the higher playback speed of the film-projector.

Also, interlaced video is a trick comprised of two fields of half-resolution played at virtually the same moment.

When you transfer film to video, BOTH fields have the same film info, which I believe makes the film "look" better on video than video.

I have no idea how film transfers to the new "Progressive Scan" Hi-def video will be affected.

"Progressive Scan" is in fact a video tribute to film!

Each video frame is scanned only once, there is no A or B frame as is currently used with standard video.

Alex

[Alex]

What does TOC mean?

[ptryk]

i got the following from kodak with an excel file showing a chart of granularity (if anyone would like a copy, send me a mail, and i will send it along!):

-------------------------------------
"The resolving power of our Super 8 films are:

Filmtype ISO-RPL

Kodachrome 40 63 lines/mm (TOC 1.6:1)
100 lines/mm (TOC 1000:1)

Ektachrome 7240 40 lines/mm (TOC 1.6:1)
EI 125T 100 lines/mm (TOC 1000:1)

Tri-X (b/w reversal) 50 lines/mm (TOC 1.6
125 lines/mm (TOC 1000:1)

Please see the attached mail and file for our negative Super 8, 200T."

[mattias]

it basically means contrast ratio. the difference is due to the gradual falloff i mentioned before.