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-   -   Tutorial or recommended reading for how to apply photography knowledge to DV? (https://www.dvinfo.net/forum/open-dv-discussion/485531-tutorial-recommended-reading-how-apply-photography-knowledge-dv.html)

Bob Mikleson October 1st, 2010 05:28 AM

Tutorial or recommended reading for how to apply photography knowledge to DV?
 
I'm a fairly advanced photography and I have a very comfortable understanding of all the terminology, principals, etc. and I'm about to embark on a fairly ambitious project but I have never done video before. I have a canon 5D MK II but might also use something like a Sony PMW-EX1. When doing some initial reading I've noticed that the terminology with DV is in some ways completely different.

Sometimes I can see how it translates pretty easily - i.e. iris = aperture but with others not so much. For example I wanted to see how the low light performance of a Sony PMW-EX1 stacks up against my 5d and I realized they aren't rated in ISO but instead sensitivity. I read in some forums there is a way to convert but it is a somewhat tedious process involving a gray card and light meter, etc, etc. Also I'm a little fuzzy on shutter speed in the video world. I suppose that perhaps you want to have some motion blur due to shutter speed when you shoot motion pictures to get a smoother overall effect - is this true? Would 1/25 be the slowest shutter speed you can set when shooting 24 frames per second? What is a good common all around rule of thumb shutter speed for video/motion film if one even exists?

Can anyone give me some recommendations? Besides learning about the broad concepts how about some tutorials on doing video with the 5D MKII?

So what's the best way to bring myself up to speed both to learn the general principals and how I might use a dedicated video cam as well as how to make the most of my 5d MK II. I've read my 5d manual cover to cover so I'm familiar with the camera but reading the manual doesn't make you a good photographer so I'm sure it also wont' make you a good videographer.

Bryan Cantwell October 1st, 2010 06:51 AM

This should help you out with understanding shutter speed and its effects: 180 Degree Shutter – Learn It, Live It, Love It

Bob Mikleson October 1st, 2010 03:48 PM

Oh yea that's one I forgot shutter angle! Leads me to another question of what's overcranking or undercranking? Also when would you want to break that 180 degree rule? I'm not clear, they allude to the fact that you might want to do it for soem special case but not when or why.

Also when they talk about the "statcatto" effect by using very fast shutters speeds - do they mean something like "jerky motion?" If memory serves correctly I guess that's what saving private ryan was like.

This gave a great understanding of shutter angle though thanks - now it's clear!



Does anyone have any other recommendations that go more in depth in general about doing video? Especially coming from a photography background?

Jonathan Levin October 3rd, 2010 10:34 AM

Bob,

"Over cranking" is best described as film/video that appears to be in slow motion. In the old film days when film was projected at either 18 (silent) or 24(sound)FPS, if film was over cranked in camera i.e. shooting at 60fps, and then projected, the film would appear in slow motion.

Undercaranking is the opposite. Think time lapse here, i.e. seeing a day go by from sun up to sun down in a matter of seconds or minutes. Here you are shooting one frame every xxx second/minute/hour etc. So if you shot 48 seperate frames through out a day, and projected that footage at 24fps on the 'ol projector, the "movie" would be 2 seconds long, but you would see the day go by that fast.

That's an extreme example and using the film analogy dates me, but it gives the basic principle which I believe for the most part also applies to video.

Do a search for over/undercranking in google. Lot's of info written better than this art student alumni.

Jonathan

Bob Mikleson October 4th, 2010 03:33 PM

Makes perfect sense thanks... I guess what really must be dated are the TERMS... I guess they come from the time when motion picture cameras actually had to be cranked by hand.

Bruce Foreman October 5th, 2010 11:05 AM

Bob,

As you immerse yourself in doing something with the 5D MkII and dedicated video cameras you become pretty familiar with the jargon. Just remember that like still photography, you can get "flooded" with a lot of theory in video.

Like the 180 degree shutter. 24fps in the film days was the best compromise between film consumption economy and image quality that worked with most people's persistence of vision. The 24p frame rate setting we see on a lot of today's video stuff is still a "holdover" from the film era.

Since in video we are not dealing with a mechanical rotating shutter disk we are not "locked" into the 1/48th of a second shutter speed the mechanical setup with the 180 degree cutout on the shutter disk dictated at 24fps. The "film look" purists would set their video cams at 1/48th if they could. But for us in a practical sense it might work like this:

On most DSLRs we have 1/50th and there is for us no practical difference between those two (persistence of vision should allow the same amount of slight motion blur we are used to in the movie theatre). And if you live and work in a PAL region that 1/50th may be your best starting point (and you should get very little "flickering" effect from lights powered by 50Hz current).

I live and work in NTSC "country" and artificial lighting is driven by 60Hz current so for me the "starting point" on shutter speed is 1/60th of a second and again due to persistence of vision there is not a lot of difference between 1/48th and 1/60th. There is enough motion blur to keep the moving image from "strobing" or suffering from a "staccato" effect.

Higher shutter speeds do not necessarily cause problems, much depends on how much motion you are dealing with. A couple of times I needed to do an outdoors demo shot using a 50mm f1.8 lens, and had no ND filters on hand to reduce light and therefore get the shutter speed down so that was around 1/1500th in that setting. But there was really no motion to deal with except for wind blowing hair and foliage a bit.

This may have oversimplified it a bit but set the shutter at 1/50th or 1/60th in most cases and go from there. but take that 5D MkII and start working with it. The more you use it, edit your efforts, and get out and try some more, the more you will learn "hands on" and like it.

Heiko Saele October 23rd, 2010 07:20 PM

I think the most significant difference between photo and video is the shutter speed. With video it is mostly set to x2 the frame rate (that is 1/50 for 25fps or 1/60 for 30 fps).

In photography you set you shutter speed according to your chosen aperture, and it just needs to be high enough for the kind of movement you want to capture. In videography, you need to know that anything other than x2 the framerate will give you a certain look/effect other from the normal look.
Consider yourself stuck with 1/50 or 1/60 for most of the time - you need to regulate the rest with the iris and ND filters (that are luckily available as a dial-in option on all professional video cameras - though not on video dslrs)

Jim Andrada October 23rd, 2010 08:16 PM

By the way, I think the"overcranking/undercranking" terminology dates back to when there was a real crank handle sticking out the side of the camera which the cameraman turned by hand.


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