Question?

S

Steve2012

Well-known member
If 1080i/p is considered High Def, and 35mm film is 2k res, & the Red shoots at 4k, what are we looking at when we watch a movie on Blue Ray, HBO or any other medium that is advertising HD?

Steve
 
35mm is not really "2k res." It is film and has no pixels. 2k has, for a while, been used as the DI resolution to preserve the integrity of the original print.

For distribution on disc or HD cable/satellite you're watching 1080i, 1080p, or 720p depending really on the network or the source. A lot of places are broadcasting from h.264 source files as well, at the same resolutions.
 
Steve2012 said:
The question is, what are we really watching? & why shoot 4k only to down res to 1080?
Click to expand...

The same reason we shoot on DVCPRO50 or DBeta and ingest at 10-bit uncompressed for something that will be released on MPEG-2 compressed DVD: the law of diminishing returns. Digital non-linear editing is going to take a toll on the image once effects and transitions are rendered, since that recompresses frames. Output compression will also take a toll since it has to reduce the file size to fit on a DVD. So at each stage, some information is lost. The more information you start with, the better choices the compression algortihm has to make when tossing out some of the data.

The link you provided makes a few interesting points... and a valid one there at the end. But really, I'm not sure the point you're trying to make here.
 
Steve2012 said:
Then I present you with this


http://www.filmschoolonline.com/sample_lessons/sample_lesson_HD_vs_35mm.htm



The question is, what are we really watching? & why shoot 4k only to down res to 1080?
Click to expand...

You're staring at the bark, and missing the forest.

First, you are assuming that "film" is film. It's not. There is a VERY noticeable difference between Kodak Vision2 5218 and something like Fuji Eterna 250D. They respond to light differently, have different characteristics in how they render color, etc. And a film camera has a series of lenses used on it. A vintage Cooke lens will impart a VERY different look to an Arri Ultra Prime or even a more modern Cooke S4 lens. That film is then scanned at 2k, or 4k depending. Some things are shot on 70mm or IMAX. THey are scanned at 6k or 8k. Those scans are brought into computers in different ways. Each step in the workflow imparts a different look and feel to what we started with.

Then there is the issue of the print made from that. Kodak and Fuji offer different stocks for this and they have different looks.

When we shoot HD (I say "we" meaning us mere mortals shooting with our small HD cameras) we are shooting with generally vastly inferior lenses. We are generally shooting onto small sensors. Our cameras respond to light very differently than film stock. We do all sorts of things to try to impart a "film-look" to our footage.

Looking at only the sharpness and MTF between film and HD is like trying to compare two racing cars by staring at the paint.
 
C2V said:
The link you provided makes a few interesting points... and a valid one there at the end. But really, I'm not sure the point you're trying to make here.
Click to expand...

Thanks to both you guys.

Not trying to make a point, just could'nt wrap my head around why I would want to shoot 4k for example, when the resolution is eventually only being displayed at 1080? if you get what im trying to say.

In the link I provided, the example of comparison was based on 1080 lines of horizontal resolution HD against that of 35mm in a regular sized movie theatre. The results were negligible and you could'nt really see the difference in resolution between the two.

I have been spending some time looking into HD, as I know the time is comming in the next year for me to purchase & was just wondering why someone would choose a Red over say, HVX200.

I think you guys answered the question with the whole compression, loss of data thing.


Steve
 
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