GH2 crop factor 1.86x or 2x ?

yoclay said:
Despite those with a videocentric viewpoint, here is the reality:Example: Panasonic 20mm ].......Like it or not, welcome to the world of DSLR cameras.
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Not just DSLRs. Over the past 10 or 12 years, i.e., beginning pre-DSLR, every video camera I recall shopping for (all less than $5000 admittedly) were advertised or listed with "35mm equivalent" lens specs.
 
GrahamH said:
Not just DSLRs. Over the past 10 or 12 years, i.e., beginning pre-DSLR, every video camera I recall shopping for (all less than $5000 admittedly) were advertised or listed with "35mm equivalent" lens specs.
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Because that's what real world people are more accustomed to. But if you have a cinematography background, those numbers will be off. I understand both sides of this argument, honestly, but I don't understand why those from the cinematography background refused to acknowledge that a consumer stills camera will be compared to the world of photography.

BTW- Phillip Bloom has been alerted to the existence of this thread. His comment on twitter made me laugh:
Dvxuser. Mmmm. They need to remember that full frame DSLR is not what came first. Film did and was all "full frame"! :)
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Not that I necessarily agree with everything Mr. Bloom says, but he seems to be at least one cinematographer who feels rather strongly against using s35 as the reference.
 
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For consumers who are not that familiar with cinematography or Super 35, a manufacturer will have an easier time saying 35mm equivalent (which we are assuming means FF) because that's what consumers are familiar with.

Here's the thing. No one is disputing that the crop factor for 4/3 compared to FF is 1.86 or 2 or 2.1 or whatever it actually is. However, there's also a crop factor when compared to Super 35, which for the GH2 is 1.3. I think we can all agree on that. There's 2 different crop factors that can be used.

However, as someone entering the world of cinematography it is important to learn the world of cinematography, and that world is Super 35 based at this time. There was a recent thread over at RedUser discussing the future for sensor size and lens image circle size and if it will continue to increase. Perhaps one day cinematography will change to FF or something different, but right now it's Super 35 and any cinematographer will talk in terms of Super 35. You start talking to a cinematographer in terms of FF now and you'll get nowhere fast.
 
M. Gilden said:
Not that I necessarily agree with everything Mr. Bloom says all the time, but thought this was funny.
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Might want to remind him that motion picture film has never been "full frame"... :thumbsup:

(yes, there was vistavision, but come on, there was also 9.5mm, so no need to get esoteric. Movies have been shot on 35mm film from the earliest days, and 99.998% of all films shot on film have been shot with the 35mm film aperture, either "academy" or "super", and none of that is "full frame")
 
M. Gilden said:
Because that's what real world people are more accustomed to. But if you have a cinematography background, those numbers will be off. I understand both sides of this argument, honestly, but I don't understand why those from the cinematography background refused to acknowledge that a consumer stills camera will be compared to the world of photography.

BTW- Phillip Bloom has been alerted to the existence of this thread. His comment on twitter made me laugh:


Not that I necessarily agree with everything Mr. Bloom says, but he seems to be at least one cinematographer who feels rather strongly against using s35 as the reference.
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I don't know Phillip Bloom's background. Did it start with photography? If so, that might be why? Cinematography may have started out as FF (I don't think it did), but it also started out as a 4x3 (or close to it) aspect ratio. Things change... now it's widescreen and Super 35. One day it may go back to FF or something larger and all will need to change again. IMAX is certainly picking up steam albeit very slowly. But right now cinematography is Super 35. For those with a photography background, yes FF is easier to think about. But when you enter a new field you need to learn the ways of that field and not expect it to change to what you're familiar with because it's easier for you, especially when there's only a couple cameras that are FF that might be used for shooting video.
 
Barry_Green said:
Might want to remind him that motion picture film has never been "full frame"... :thumbsup:

(yes, there was vistavision, but come on, there was also 9.5mm, so no need to get esoteric. Movies have been shot on 35mm film from the earliest days, and 99.998% of all films shot on film have been shot with the 35mm film aperture, either "academy" or "super", and none of that is "full frame")
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I don't know my film history as well as I should I guess. What was the first film stock? Was it smaller than 16mm? Should we start talking crop factor in 16mm terms, or 8mm?
 
From Wikipedia http://en.wikipedia.org/wiki/35_mm_film#Technical_specifications :

35 mm spherical[SUP][SUP][44][/SUP][/SUP]
  • aspect ratio: 1.37:1 on camera aperture; 1.85:1 and 1.66:1 are hard or soft matted over this
  • camera aperture: 0.866 by 0.630 in (22 by 16 mm)
  • projector aperture (full 1.37:1): 0.825 by 0.602 in (21 by 15 mm)
  • projector aperture (1.66:1): 0.825 by 0.497 in (21 by 13 mm)
  • projector aperture (1.85:1): 0.825 by 0.446 in (21 by 11 mm)
  • TV station aperture: 0.816 by 0.612 in (21 by 16 mm)
  • TV transmission: 0.792 by 0.594 in (20 by 15 mm)
  • TV safe action: 0.713 by 0.535 in (18 by 14 mm); corner radii: 0.143 in (3.6 mm)
  • TV safe titles: 0.630 by 0.475 in (16 by 12 mm); corner radii: 0.125 in (3.2 mm)
Super 35 mm film[SUP][SUP][44][/SUP][/SUP]
  • aspect ratio: 1.33:1 on 4-perf camera aperture
  • camera aperture (4-perf): 0.980" by 0.735" (25 by 19mm)
  • picture used (35 mm anamorphic): 0.945 in (24.00 mm) by 0.394 in (10.00 mm)
  • picture used (70 mm blowup): 0.945 in (24.00 mm) by 0.430 in (10.92 mm)
  • picture used (35 mm flat 1.85): 0.945 in (24.00 mm) by 0.511 in (12.97 mm)
35 mm anamorphic[SUP][SUP][44][/SUP][/SUP]
  • aspect ratio: 2.39:1, in a 1.19:1 frame with a 2× horizontal anamorphosis
  • camera aperture: 0.866 in (22.00 mm) by 0.732 in (18.59 mm)
  • projector aperture: 0.825 in (20.96 mm) by 0.690 in (17.53 mm)
.
.
.
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No full frame there. In fact, 35mm as used in cinematography has been much smaller than full frame.
 
Mike@AF said:
I don't know my film history as well as I should I guess. What was the first film stock? Was it smaller than 16mm? Should we start talking crop factor in 16mm terms, or 8mm?
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Depends on what you mean by "first", of course, but movie film's primarily been 35mm since Edison.
http://wichm.home.xs4all.nl/filmsize.html

The fun thing is, in today's crush for "wider and wider", film was originally (and still is primarily) a 4x3 format! The reason TVs were 4x3 is because film was 4x3. Modern movies get their 1.85:1 aspect ratio by cropping (throwing away) chunks of the frame...
 
http://en.wikipedia.org/wiki/List_of_film_formats

That's probably a better article. It shows the Edison format of 35mm film, 0.98" x 0.735", dating back to 1891. Which is basically exactly the same as S35mm movie film that's used today.

Lots of different sizes in-between, and actually S35 wasn't used for decades; they shrunk the frame size down to normal 35mm film to make room for the soundtrack. S35 is 24.89mm, normal 35mm is 22mm wide. Normal35 has been the standard since sound was introduced, with very few films using Super35, and mainly those were specifically as a replacement for anamorphic. Nobody used S35 for normal motion picture work because you couldn't make an optical print of S35 material, you had to shrink it down in order to make room for the soundtrack. In recent years with the advent of the Digital Intermediate, S35 has become more popular because people don't typically do optical printing anymore, they digitally scan everything, and that eliminated the drawback of using S35.
 
As far as "full frame" in the movies, that would be 65mm film (70mm when projected). Wiki has a list of all the films they could find that were shot on 65mm... Considering that the IMDB has a total of 268,000 feature films, but only about 50 in history have been shot in "full frame", that's why we say that largely it's irrelevant to cinema work. Sure, some big pictures were shot in it, but very few, and 65mm makes up such an incredibly tiny minority of the # of films shot overall. By those numbers, "full frame" was used in 0.02% of the films shot (and that doesn't count the hundreds of thousands of short films, documentaries, movies of the week, and all the rest that were all shot on 35mm film).

Heck, "full frame" hasn't been used to shoot anything since 1996's "Hamlet" -- that's 16 years of it going completely unused... (except for a documentary, "Samsara").
 
Ah, that's the article I was looking for. Good info. Full frame clearly doesn't apply to cinematography right now.
 
Barry_Green said:
Heck, "full frame" hasn't been used to shoot anything since 1996's "Hamlet" -- that's 16 years of it going completely unused... (except for a documentary, "Samsara").
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I believe Paul Thomas Anderson's new film "The Master" was shot on 65mm but I could be wrong.

Edit: Actually after a bit of research, it looks like it's split between 65mm and 35mm.
 
M. Gilden said:
BTW- Phillip Bloom has been alerted to the existence of this thread. His comment on twitter made me laugh:


Not that I necessarily agree with everything Mr. Bloom says, but he seems to be at least one cinematographer who feels rather strongly against using s35 as the reference.
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Weird, it made me sigh and a little sad inside that he just mis-informed an entire community of followers. I hope he meant something else and it just wouldn't fit in twitter's letter limit.

Edit here:

Barry_Green said:
Might want to remind him that motion picture film has never been "full frame"...
thumbsup.gif


(yes, there was vistavision, but come on, there was also 9.5mm, so no need to get esoteric. Movies have been shot on 35mm film from the earliest days, and 99.998% of all films shot on film have been shot with the 35mm film aperture, either "academy" or "super", and none of that is "full frame")
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Not a single one of those... blerg...
 
I think perhaps Mr. Bloom was talking about full frame 35mm for photography being an existing standard before cinema s35 was around.

At least, that's how I understood it.
 
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Barry_Green said:
The spec for the GH2 has never been released, but we kind of back-calculated it to be 18.9mm based on the number of quoted pixels on the chip overall, and the number of pixels used in each of its modes.
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Hi Barry,

The sensor in 4:3 mode is quoted as measuring 17.3mm horizontally, and yields an image 4608px wide in that mode. In 16:9 mode, we know it yields an image 4976px wide. Therefore, if I'm not mistaken, wouldn't the math needed to determine the horizontal measurement of the sensor in 16:9 mode be the following?

17.3mm / 4608 * 4976 = 18.68mm

Any thoughts on this? Is this too simplistic for some reason?
 
When I started the thread my goal was to find the crop factor between GH2 and 35mm Still because I come from the 35mm still background.

I think the discussion about to find the standard crop factor for everybody is not important and it is a wrong way to go.
each people come from a different background, some from still, some from 35 cine, some from 16 cine, some from medium format photo, and so on...
and who started shooting with M43 does not come from any background...
so the important point is to know the crop factor between you actual camera and the camera you used to shoot in the past. for me it is GH2 x 35mm STILL.

when i was a teenager (about 15 years old) my father got a Canon FD AE1 Program, a realy nice machine, used from a friend. I become excited, started shooting and reading about photo. So I did some extensive workshops to learn it better and start shooting weddings with it. the camera came with a Canon Book showing all FD lenses From 7.5mm to 1200mm, a very nice book with photos comparing the lenses field of view and showing photos of the best aplications for each lens.

When using the Canon FD AE1 Program Full Frame Still camera, In my experience shooting people i found some rules for using the lenses. To shoot a portrait or a face close up I need to be 1,5 meter or more far away from the person. because if I get closer the nose would increase in size. So the best lens for a portrait (from chest to head) is from 70mm to 100mm (in 35mm still) and this will be 35mm to 50mm in GH2. For a face close up the best lens is a 135mm in full frame still (about 70mm in GH2). To shoot a group of people i found the best wide angle is the 35mm because any wider than this have distortions, so I just used the 28mm when realy needed. 35mm in still will be close to a 17mm or 18mm in GH2. So following this rules and using a great flash (the 299T) I got great photos and everybody loved my job with the Canon Fd AE1 Program. Due to this background it is important to me to know the GH2 crop factor comparing to 35mm still to know the best lens for each situation.

You can see a little portrait movie shoot with the GH2 with lenses from 14mm to 85mm and you will see the difference in the person face, showing the big nose with wider lenses and good composition with the correct lens for the situation and also the difference in background for each lens used. the link is:

http://vimeo.com/34423217
 
dishan said:
Its not about not wanting to use lights. I used to use full sized ENG style cameras and still have one for that type of shooting if I need it. The DSLR opened up the ability to shoot in natural lighting, however. I can get live event and other real-world footage that would have been impossibly grainy on my old cameras.
Fast primes brought me here. Otherwise I would have been happily using my big camera with its XLR inputs and superficial client confidence. Sadly, fast primes tend to be pretty long in focal points. You find the most common fast option being 50mm. Why? Because on a photography camera, that is considered the standard "portrait lens" size. It is the most common, and the most manufactured (and therefore also the easiest and cheapest to find). This is where crop sensors become an issue to many of us. To get the same FOV as the 50mm portrait lens, the GH2 needs something like a 28mm. To get really great low light performance, finding a 50mm f/1.4 is stupid easy. But finding a 28mm F/1.4? Not so much. Sure, there is the Lumix pancake lens at F1.7, but that is one of the rare options that exist and will only be compatible with other micro 4/3rds mount cameras in the future.
The general advice on this forum is to invest in glass for the long haul, and not in camera bodies. That means I'd like invest in full frame lenses that will be compatible on just about any body I choose, and hence the reference to full frame crop values.

Not that any of this really matters, use what works for you and your background. Those of us who are just starting out in the world of interchangeable lens cameras don't see the value in comparing to the old cinema film size, when everything else we see is comparing it to full frame. But if you are coming from that background I get it. Aren't we all entitled to our own perspective here? Since when are we deciding industry standards?
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Having purchased video cameras in the past costing well over $10,000.00 and buying a whole new one every time to replace it I just cannot justify the obsession of being able to use $3,000.00 worth of lenses. Yeah it would be nice but keep in mind not all lenses work to their optimal level on different mounts. Sure they can be adapted but there is always some level of control lost in the translation. Personally I don't mind buying a bunch of M4/3 lenses because they work damn well and honestly in comparison to the cost of a $10,000.00 + video camera personally I don't care if I would have to sell the whole kit to buy whats next. Overall I have about $1,200.00 invested in M4/3 which is cheaper then most crappy consumer video cameras. Even if I had to throw all my M4/3 glass in the trash it would still all be worth it in the end.

The way I look at it is that I am not going to be concerned about buying the 20mm f1.7 and if it will be future proof because the damn thing was only $350.00. Heck there was a time when my batteries cost more then that.

On the flip side if you do need telephoto then a 135mm f2.0 is pretty awesome on M4/3. That is something that is virtually impossible to have on full frame. I have yet to find a 270mm f2.0 lens for any camera.
 
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