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*lol* you got no idea what i'm talking about, do you? sorry, but not only are you actually wong, you've also missed the point of this thread completely...Lucas Lightfeat wrote: Mattias, I'm amazed that you're asking a question about this, as you are normaly such an authority on cinematographic related details, but I can assure you that 35mm has a much shallower dof than 8mm.
thanks, that's what i thought. however, these numbers might actually prove that format doesn't matter, since such a small circle is smaller than what the emulsion can register. given a resolving power of 120 lines/mm the smallest circle that can be registered is 1/600", so who cares if details even smaller are sharp or not? ;-) perhaps using 1/1000" is enough to be "safe" and to take account for the uneven graininess which as we know can increase the sharpness slightly.jessh wrote:'Traditionally 1/500" circle of confusion was used for 35mm filming, and 1/1000" was used for 16mm'(Appendix B)
The reason that a smaller circle of confusion is used with 16mm than 35mm is that ther 16mm frame has to be magnified more in order to cover the same space.
Yes, I would tend to agree. Again, as I mentioned in a previous post, "apparent" depth of field can be affected by a variety of outside influences not taken into account in basic depth of field charts. However, from a practical standpoint, I still feel smaller formats like S8 still have a functional DOF advantage over larger formats for most shooting situations, if one wants deeper depth of field. Having done some foreground miniatures in both formats, I can tell you that doing so in smaller formats is quite easy while maintaining enough depth of field in 35mm is a bit of a challenge. That said, one of the things that does help is when the resolution of the film is so limited that differences in COC size become moot and areas of the film not as sharp as others all tend to look the same due to limitations in film resolution and not so much lens resolution. This only becomes really critical if the image is blown up too much and it becomes apparent that parts of the image are not as sharp as they look when viewed small.mattias wrote:these numbers might actually prove that format doesn't matter, since such a small circle is smaller than what the emulsion can register.
RDepth of Field
Depth of field is the measurement of the area in front of and behind the subject that is held in acceptable focus. You can get a simple understanding of the phenomenon by holding your hand quite close in front of your face – and then focusing your eyes on your hand. Notice the quality of the background. It is very soft and out-of-focus. Now slowly move your hand away from your face, continuing to focus your eyes on that hand. Notice that, as your hand moves away from your face, the background comes into sharper focus.
This is a demonstration of one of the factors, distance to subject, that determines the depth of field of a given shot. There are two other variables that the photographer or cinematographer controls – focal length and f or t stop. And then, an inherent characteristic of any given imaging system is the actual size of the aerial image as it converges on the focal plane. This determines the “resting†depth of field. For example, a larger image (like you get with 65mm film) has very shallow depth of field while a relatively small image (like that of Super 8 film) has much greater depth of field.
But, overall film capture systems have a naturally shallow depth of field that can be easily manipulated. This is extremely important in terms of trying to focus the viewers’ attention to different areas in a scene.
The 2/3" chip size of current digital video equipment results in a smaller capture area than that of film, giving it an inherently deep depth of field – which is not easy to manipulate. That’s usually how you can tell the difference between reality-based television programming, for example, and dramas, sitcoms, TV movies or high-end commercials.
but it's not a basic truth, and it's not even a truth. you're talking about something else than the rest of us.Lucas Lightfeat wrote:I restated to you a basic truth of cinematography
you're talking about a difference at the same field of view, and not at the same focal length like the rest of us. everybody knows that 35 mm has less dof than s8 at the same field of view, but we're lightyears beyond that in this discussion. the question is whether you can use a dof chart for a larger format for super-8.but they do not change the simple fact that 35mm has a shallower dof than Super8 under all but the most unreasonable conditions
yes it does, which three of the later posts in this thread have clearly proven. i must say i find your disrespect for logic and theory quite stunning.you asked if Super8 actually had a smaller dof than 35 - well, no, it doesn't
where are you getting this number? My calculations are saying that for 120lines/mm the smallest point would be 1/3048"mattias wrote:given a resolving power of 120 lines/mm the smallest circle that can be registered is 1/600", so who cares if details even smaller are sharp or not? ;-)
Apart:f/Calc is a calculator for photographic formulas. These formulas are at the heart of many interesting questions about the technical side of photography. You could compute these functions by hand, but they range from tedious to difficult, even with a good scientific calculator. When you let f/Calc do the hard work, you gain an intuitive feel for what the results mean, because you can quickly try new input values to see how they affect the result.