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s16 frame = How many Megapixels?


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#1 Marcus Frakes

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Posted 12 December 2005 - 07:17 PM

In another post, members say Super16 is about 2,000. I believe they are talking about the # of vertical lines. But how many pixels are estimated to be in a s16 frame? How about in a 35mm frame?

Just a coment here. A professional photgrapher was raving about his new 16 megapixel camera. He said it's to the point where he cannot see any "additional" detail when using 35mm film...of course these are still images. And I believe the best HD camera around is 12 mp?
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#2 David Mullen ASC

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Posted 12 December 2005 - 07:29 PM

2000 refers to horizontal pixels, so total megapixels per frame depends on the aspect ratio. For example, 2048 X 1540 pixels would be a 4x3 aspect ratio, but it would be 3.15 MP frame.

Film doesn't have pixels. You could scan a piece of film at 16,000 pixels across (16K) if you wanted to -- the only question is what is the least amount of pixels you need to capture every piece of grain & detail on the frame. Generally the 35mm movie frame is considered to be the equivalent of 4000 pixels across, so if you're talking about a 4x3 negative, or 4000 x 3000, that's 12 MP. In most scanners, 4K resolution is 4096 pixels across and 2K resolution is 2048 pixels across. How many down depends on the aspect ratio.

If 35mm is around 4K pixels across, and the 16mm frame is half the width of the 35mm frame, then you can scan a 16mm frame a 2K across and get the same resolution as scanning 35mm at 4K across.

HD is either 1920 x 1080 pixels or 1280 x 720 pixels (although some HD tape formats shave some of that down -- for example, HDCAM is 1440 x 1080 pixels, but the pixels aren't square, so the aspect ratio is still 16x9.)

1920 x 1080 is a 2.2 MP frame -- much smaller than a 4x3 35mm frame that is 12 MP in theory. So HD is closer to a 2K scan of Super-16 in terms of resolution, except that HD doesn't have grain (noise maybe, but no grain.) Lack of grain gives you more flexibility in resizing the image, hence why HD transferred to 35mm doesn't seem as low-rez as a Super-16 blow-up even though in theory it is. Because there is no grain being enlarged in the process as with S16-to-35mm. Grain size is also the reason why a 2K scan of Super-16 doesn't look just like a 2K scan of 35mm.

Edited by David Mullen, 12 December 2005 - 07:30 PM.

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#3 santo

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Posted 12 December 2005 - 08:19 PM

The idea that HD is even remotely close to 35mm film is a joke. It is common practise to shoot super 16 so you can oversample for an HD transfer.

I don't know if it is even remotely possible to create a video camera that could shoot with 16k resolution with today's technology. Even if you could, it would not have the life and soul of film origination. Not even remotely. Digital origination for motion pictures is dead imagery. It's actually quite the opposite for still photography where it can now, after all these years, finally produce imagery which is equal to 35mm still. I think there is nothing that is wrong with digital still image taken to its highest level in the very best still photography. It is hard to fault. It was inevitable. But in motion pictures, it has a hell of a long way to go, and will never get to there -- attempts will always appear artificial and derived. The current $200 thousand dollar camera set-ups of Lucas and his newfound lackey Rodriguez look like dead and lifeless video games next to film. It all goes way beyond resolving power, which is not even 1/8th there yet.

I think HD has its place as a terrific medium for television and certainly as an edit intermediate for low budget filmmaking originating on film. It has its places there and, on the visible horizon, decent 2k cameras. HOWEVER, digital will never match film for the same reason that painting synthetic media on synthetic surfaces will never match oil on canvas. THERE IS NO LIFE THERE.

Welcome to reality. Reality does not change no matter the technological drive by greedy mega-corporations like Sony. Which makes GREAT televisions.
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#4 David Mullen ASC

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Posted 12 December 2005 - 09:27 PM

HOWEVER, digital will never match film for the same reason that painting synthetic media on synthetic surfaces will never match oil on canvas.


Yes, but that doesn't mean you can't create art with synthetic materials. A sculpture in marble isn't necessarily superior or worse than one carved in wood or created in bronze using molds (of course, those are all natural materials...)

Anyway, never is a big word. I can show you articles in American Cinematographer from the 1930's where people say that color will never be any good for shooting dramas and that most movies will always be shot in black & white.

A difference that makes no difference is no difference -- and someday the differences between film and digital images will be close enough (as it is becoming with digital still cameras) that it will matter less and less which you choose. Anyway, I'm not going to say something is impossible technically to accomplish. Besides, film keeps getting sharper and finer-grained and some people think that that makes it look more digital!

Combine that with digital intermediates and digital projection and CGI-heavy efx movies, and we're halfway there in making movies look more digital, which makes it easier to accept the look of digital origination.

My prediction is that most filmmakers will find some common ground between the two looks. Not today or next year, but by the time digital origination really takes off, people will have been prepared for the changeover already. It won't be an abrupt change in look that people will be unprepared to accept.
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#5 Marcus Frakes

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Posted 13 December 2005 - 04:06 AM

Thanks for the comments guys. I want to rope this discussion in BEFORE it turns into another film vs. digital flame war. :ph34r: Nobody needs to waste any more time and bandwidth on that one! I used both mediums in film school and now I choose film - for all the right reasons. The discussion also becomes pointless (yields no difference?) because 'filmmakers" add digital content to film as a normal routine and it's totally accepted. Why do we forget this? Thus the added people, buildings, cars, skylines, eco-systems, are already in digital format. I can't tell my programs to render those extra houses in Kodak 7218T film stock.

This takes me to the original question (in which I probably should not have said the word "megapixel" in a 16mm forum) but nonetheless because of the digital work I do, I needed to calculate approximate resolutions (in pixels) of film.

Also what was meant by a "common practice is to shoot super 16 so you can oversample for an HD transfer"?
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#6 Sam Wells

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Posted 13 December 2005 - 10:32 AM

Arri has what they call a "3K" test/demo scan of S16 done with the Arriscan telecine. I haven't seen it though.

-Sam
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#7 Erdwolf_TVL

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Posted 13 December 2005 - 11:01 AM

Thanks for the comments guys. I want to rope this discussion in BEFORE it turns into another film vs. digital flame war. :ph34r: Nobody needs to waste any more time and bandwidth on that one! I used both mediums in film school and now I choose film - for all the right reasons. The discussion also becomes pointless (yields no difference?) because 'filmmakers" add digital content to film as a normal routine and it's totally accepted. Why do we forget this? Thus the added people, buildings, cars, skylines, eco-systems, are already in digital format. I can't tell my programs to render those extra houses in Kodak 7218T film stock.

This takes me to the original question (in which I probably should not have said the word "megapixel" in a 16mm forum) but nonetheless because of the digital work I do, I needed to calculate approximate resolutions (in pixels) of film.

Also what was meant by a "common practice is to shoot super 16 so you can oversample for an HD transfer"?


Would it be logical to say that...

35mm still image is coparable to 12 megapixels digital (print comparison)

16mm has approximately 1/4 the surface area, and is therefor in the region of 4 megapixels?

And Super8 is just over 1 megapixel?

---

In theory, film's megapixel rating would be the surface are of the film / the surface area of the emulsion particles. Unfortunately, these particles are not all the same size, not all equally light sensitive and they are not dotted down in straight lines.
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#8 David Mullen ASC

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Posted 13 December 2005 - 11:13 AM

Film doesn't have pixels! The only issue is what is the minimal resolution you can scan film and retain all the information on it.

Super-16 and HD are similar in resolution, so is 2K versus HD (2048 versus 1920 pixels across). The main difference between 2K and HD is not resolution, it's data versus video in terms of how the information is stored and processed, but now with 10-bit log 4:4:4 HD, even that difference is closer than ever.

Again, the total megapixels is controlled by aspect ratio -- 4K is only 12MP if the aspect ratio is 4x3, but since most movie frames are widescreen, it is often less than that. Super-16 has a 1.68 : 1 aspect ratio, so a 2048 x 1219 scan works out to be 2.5 MP. If you scan it to full-frame HD (16x9 or 1.78 : 1), then that's 1920 x 1080, or 2.2 MP.

Edited by David Mullen, 13 December 2005 - 11:18 AM.

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#9 Marcus Frakes

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Posted 13 December 2005 - 06:39 PM

Again, the total megapixels is controlled by aspect ratio -- 4K is only 12MP if the aspect ratio is 4x3, but since most movie frames are widescreen, it is often less than that. Super-16 has a 1.68 : 1 aspect ratio, so a 2048 x 1219 scan works out to be 2.5 MP. If you scan it to full-frame HD (16x9 or 1.78 : 1), then that's 1920 x 1080, or 2.2 MP.


I calculate 1920 X 1080 and get something closer to 2.07 MP...unless I'm missing something? Also if I hear you correctly, you could do a 4K scan on Super 16, but it wouldn't get you any more significant amount of information??

Edited by Montage, 13 December 2005 - 06:39 PM.

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#10 David Mullen ASC

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Posted 13 December 2005 - 07:44 PM

I calculate 1920 X 1080 and get something closer to 2.07 MP...unless I'm missing something? Also if I hear you correctly, you could do a 4K scan on Super 16, but it wouldn't get you any more significant amount of information??


Hey, you're right (just using the calculator...)

As for a 4K scan of Super-16 being useful, it sort of depends on if you think a 4K scan of 35mm is adequate. Some people think that 35mm is more like 6K, therefore Super-16 should be scanned at 3K. You're probably pushing it in terms of usefulness though (scanning Super-16 at 4K) -- it would probably only make sense on razor-sharp low-speed film stock images... It's probably a waste of money.
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#11 Charles MacDonald

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Posted 13 December 2005 - 10:18 PM

Thus the added people, buildings, cars, skylines, eco-systems, are already in digital format. I can't tell my programs to render those extra houses in Kodak 7218T film stock.


I belive that is what the "image management" software is aiming for. You take your digital model and do a transform that emulates the "look" of a given film stock.

AS far as resoultion, The ASC seems to be pushing to have 4K accepted as the standard for Theatrical projection. Since Super16 is used to blow up to 35mm now, I would suspect that you might want to eventualy reach that level for Super16 as well.

Of course we can hope that 4K is only an intirum standrd as both digital and Film are changing rapidly.

Scaning at a higher resoultion and down converting is commom in other digital media - (My wife was a Digital audio compression Guru before she retired) - the math gets scary rather quickly but She has assured me that oversampling in audio actualy removed artifacts of the conversion process away form the desired signal. Not somthing you can casualy measure. The radomness of film grain may be effectivly doing the same thing, but putting defects when they are hard to observe.
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#12 David Mullen ASC

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Posted 13 December 2005 - 11:21 PM

AS far as resoultion, The ASC seems to be pushing to have 4K accepted as the standard for Theatrical projection. Since Super16 is used to blow up to 35mm now, I would suspect that you might want to eventualy reach that level for Super16 as well.
Of course we can hope that 4K is only an intirum standrd as both digital and Film are changing rapidly.


My point is that scanning Super-16 at 2K across is the SAME RESOLUTION as scanning 35mm at 4K, since Super-16 is half the physical width of 35mm.

Anyway, since we aren't even there yet at implementing an all-4K workflow for 35mm (which would be ideal), with very few exceptions, it's hardly an "interim" standard! There's quite a big resistence in the post community to 4K, since it is four-times the data as 2K. I can't tell you how many efx supervisors I've talked to who are opposed to 4K...

Edited by David Mullen, 13 December 2005 - 11:23 PM.

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#13 Phil Rhodes

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Posted 14 December 2005 - 06:26 AM

Hi,

I think the problem we have here is that no matter how good digital post gets, there'll always be some luddite trying to claim that 35 is still better!

Phil
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#14 David Mullen ASC

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Posted 14 December 2005 - 01:14 PM

I think it's more of an issue of squeezing every drop of quality out of the film image. Most of us want a D.I. to be the same quality level as a contact print off of the original 35mm negative -- that's the goal.

I'm doing a D.I. for the optical effects (fades & dissolves, etc.) right now for "Akeelah and the Bee", which was shot in 35mm Panavision anamorphic using the Primos. As a test, I had them scan and then record back to film, uncorrected just straight, a single shot and compared it to a contact print of the same shot at the lab's screening room.

Scanning & recording at 2K (Northlight scanner / Arrilaser) showed a slight overall softening -- acceptable, especially considering the alternative of using an optical printer to create these effects, which would have created even a bigger mismatch in grain & contrast compared to the digital version, but it did show me that I could see the loss due to using 2K. But the studio won't pay for 4K scanning even though it's an option.

On the plus side, the digitally opticals match so much better than an old optical printer dupe would that we can get away with more digital fixes in the film and have them cut into the movie.

Now one could see the advantage of 2K D.I. as being a universal equalizer in a way, because some mismatches in grain & sharpness of shots would be "dulled down" to a more consistent look, plus it would blend with 2K effects.

I just saw "Jarhead" a few weeks ago, which scanned at 4K at Efilm and downrezzed to 2K. Super-35 cropped to scope. Well, on the big screen, ILM's effects are visibly softer than the rest of the movie! And since many of these are wide shots to boot, it's especially annoying. I can only assume that ILM scanned and did all the efx work at 2K, which is why it doesn't match the surrounding 4K-to-2K footage.

Edited by David Mullen, 14 December 2005 - 01:15 PM.

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#15 Dominic Case

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Posted 14 December 2005 - 05:23 PM

But how many pixels are estimated to be in a s16 frame?

Film grain, like the resultant dye-clouds, comes in a range of sizes (that's how film has such a wide dynamic range or latitude). So you could go on with more and more pixels and still fail to capture the smallest individual dye-clouds.

But a few years ago, we scanned a 35mm frame shot on 5248, and enlarged the results. The 2K scan looked pixelly, the 4K scan looked grainy - so 4K more or less did the job.

As others have pointed out, that's roughly equivalent to 2K in a 16mm frame.

That was for a particular emulsion type. Since every film type has different sized grain, (larger grains for faster film), and the new Vision2 emulsions are finer-grained than earlier stocks, you can't realy compare anything with generic "film".

A professional photgrapher was raving about his new 16 megapixel camera.

In this context, it's not often realised that the more pixels (or photo-sites) you cram into the same-sized chip, the smaller (and therefore less-sensitive) each pixel is. As a result, the finer resolution comes with a slower speed, or more noise.

And while a pro still camera such as a digital SLR gives you your choice of lens, most consumer digital still cameras seem to have lenses that can't match the pixels. And the lenses are so slow that hand-held shots in less than bright daylight are more than often blurred.

In short, mega-pixels tend to be overrated as a selling point.
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#16 K Borowski

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Posted 14 December 2005 - 05:48 PM

In short, mega-pixels tend to be overrated as a selling point.


As a semi-pro still photographer, the way I understand it is this: the larger the sensor, the less digital noise there is. Therefore,unless your digital still camera has a 35mm sized chip (i.e. 24x36mm), your DSLR doesn't even begin to compare with 35mm. In my opinion, 35mm is not the ideal still format anyway (nor is digital). It's actually kind of silly wasting ~10% of the image area on sprocket holes that are completely unnecessary except with the high-speed mechanism of a movie camera. The pro photogs I know who stick with film tend to stick with it not for its resolution, but rather the "punchy analog" color that only film can deliver, particularly skin tones. I really have no way of showing you what I mean on a computer, but there is something that "pops-out" at you from an optically printed picture that a laser-imaged photo doesn't have. The same can be said of cine film. People generally choose film over digital because of the color and contrast more than the resolution.

Regards.
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#17 Marcus Frakes

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Posted 14 December 2005 - 07:47 PM

Then for example if I wanted to put King Kong (as digital 3d Model) on the Empire State Building/NYC skyline (shot on Super 16) I should use the following specifications:

A 2K Scan of Super 16 (w/1125 down)
A 1920X1080 res digitally created model

This would give the best match between the two formats (considering equal aspect ratios)?
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#18 Tenolian Bell

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Posted 14 December 2005 - 08:57 PM

Its true 16mm is going to generally be a grainier picture in comparison to 35mm and especially HD. You would need to shoot slower speed film to get a more fine grain image in super 16. Which does require a larger lighting package. I often shoot 200 speed as much as I can. Even pushing 7217 a stop will render a finer grain image than shooting 7218 properly exposed. I doubt in the future 16mm scanning beyond 3K will be necessary or widely practical.

At the same time improvement of film will continue. There is still room to make halide crystals more efficient at collecting light photons. Which would enable even faster films with even smaller grain.

Improvements in lens will continue. Arri is testing its new MasterPrimes, which can shoot at T1.3. Shooting with 1000 speed film at T1.3 only requires 2 foot candles for a proper exposure.

In this digital age grain has become a bad word. Its not as bad as some make it out to be and has often been used as a tool. For example, in the Metropolitan Museum here in New York. You can see old world oil paintings. When you see one of these original works of art as you look at them closely you literally see the brush strokes. These brush strokes technically are random imperfections. The brush strokes add a tactile quality and gives you a sense surface on a two dimensional image. This is the same thing grain does.

Grain gives an image a sense of texture of surface. I think it tricks your brain into the sense that you could reach out touch the image and feel the grain.

I have also heard a few mainstream DP's discuss how 35mm film has become too sharp too fine grained. A couple have attempted convvince their producers to shoot large budget films on super 16 because they wanted a less sharp image or more grain. This is diffcult with large budget films because of studio financial/distribution politics.
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#19 David Mullen ASC

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Posted 14 December 2005 - 09:06 PM

Before Phil says it, the flipside to that argument is why is a film artifact like grain considered an aesthetic benefit yet digital artifacts like noise aren't? Isn't it partially just a matter of conditioning, like why we prefer 24P over 60i?

As far as grain goes, a DP told me that he had to get everyone's commitment to pushing the 35mm footage for a TV show he was shooting by two-stops to get a grainier texture, which made me wonder why this TV show didn't just shoot in Super-16 for starters and just push one-stop if necessary.

Edited by David Mullen, 14 December 2005 - 09:08 PM.

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#20 Charles MacDonald

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Posted 14 December 2005 - 10:23 PM

Before Phil says it, the flipside to that argument is why is a film artifact like grain considered an aesthetic benefit yet digital artifacts like noise aren't? Isn't it partially just a matter of conditioning



I recall when some of the network TV shows started to originate in Video back when I was a Kid, I often found the "video look" jarring, as up until then dramatic productions on TV were done on film and the Video looked completly different. "All in the Family" is the one that comes to mind.

We probaly are inprinted that TV is live and free, while Film Production is Serious. Newer generations may not perceve that difference.
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