Over-cranking?

[Jimsimm]

Does any-one know about over cranking? The effect can be seen in 'saving private ryan'during battle sequences and the more recent 'Gladiator' in the fighting sequences. Anything to do with shutter or film speed? Cheers
Jim

and while your here check out - www.undergroundfilmworks.com

[eddie]

overcranking was used in the early days by cameramen with manually cranked cameras, who wound it too quickly, this gives the effect of slowing down the image when its projected. I think you are talking about a sped up image, almost like a strobe blur of action, which you can get by *under* cranking (I think the terms have gotten confused over the years). Ive got exactly the same effect using a camcorder with the gain on high, and on a sunny day. The camera was waved around quite a lot at a festival. The effect was identical.
So whats happening?
The gain is on. This opens the aperature, slows the film speed or decreases the shutter speed or all three.
And it was a very bright day.
Looking at the results I think what happened was that my camera *closed* the aperature, and upped the duration the shutter was open for.
Aside from all that Ive found using the gain on my camera under different circumstances can give all sorts of very weird effects. From strobing like this to blurring.
Try using high gain, a sunny day and moving camera around a lot handheld.

[eddie]

oops sorry I made a mistake. The aperature must have been opened and the shutter speed reduced. The images arent blurred at all, it looks like animation. Since the camera was moving around, the shutter must have been up quite high.
So.....
since the gain was on I think that this opened up the aperature.
since it was a sunny day the camera needed to balance the opened aperature by making the shutter time smaller.

Im not kidding, this looked exactly like the effect you mention above.

Since this is a video camera the camera effectivley took lots of stills (so for the rest of the shutter duration it used that original image (instead of blackness) and thats what you see.

Sorry Ive messed up this explaination, but I think that the above was what was happening

With a film camera you can change the filmspeed, so *slow* the speed down when you are shooting, this then appears sped up when its projected at the correct speed.

With a video camera you cant change the film speed (please someone correct me if Im wrong)

[marti-c]

mmmmmm. I've got some comments on this but the last bit isspeculation so dont take everything as verbatim.

Eddie the effect you were describing sounds like you stuck the gain on and electronically the camera would have a fully opened apeture because it's been told that there is very little light. OK. Now whats happened is too much light is getting in so to get a correct exposure the camera has to up the shutter speed to lets say 1/500. This changes 2 characteristics on the lens, the depth of field lowers and the strobe effect you describe.

I use this trick during a bright day when a normal shutter speed would keep everything in focus and i want to pull focus between two objects.( I dont touch the gain though, just the shutter speed manually. But if you have auto shutter speed then switching the gain forces the camera to change shutter speed)

Next up, the gladiator effect.

I read somewhere that the shutter speed is changed to a variable that is divisable from 24 (frames per second) i.e 8 then every frame is duplicated twice more to bring it back up to 24 frames and this give the stroby effect on saving private ryan and gladiator. I think i have the article somewhere so maybe i will dig it out. You could try this out manually in premiere by cutting and copying in you timeline. It might take a while but experiment to see if it works just for a few seconds.

marti

[marti-c]

mmmmmm. I've got some comments on this but the last bit isspeculation so dont take everything as verbatim.

Eddie the effect you were describing sounds like you stuck the gain on and electronically the camera would have a fully opened apeture because it's been told that there is very little light. OK. Now whats happened is too much light is getting in so to get a correct exposure the camera has to up the shutter speed to lets say 1/500. This changes 2 characteristics on the lens, the depth of field lowers and the strobe effect you describe.

I use this trick during a bright day when a normal shutter speed would keep everything in focus and i want to pull focus between two objects.( I dont touch the gain though, just the shutter speed manually. But if you have auto shutter speed then switching the gain forces the camera to change shutter speed)

Next up, the gladiator effect.

I read somewhere that the shutter speed is changed to a variable that is divisable from 24 (frames per second) i.e 8 then every frame is duplicated twice more to bring it back up to 24 frames and this give the stroby effect on saving private ryan and gladiator. I think i have the article somewhere so maybe i will dig it out. You could try this out manually in premiere by cutting and copying in you timeline. It might take a while but experiment to see if it works just for a few seconds.

marti

[Red House Painter]

i've noticed this effect and have been wondering what it is for ages. I don't know if this is what you are talking about marti-c but animation is done in a similar way where there are 12 differnt frames shown twice to make 24 per second as it saves time.

[eddie]

Thanks Marti-c, thats a better explaination.

Animators often cut corners by shooting 2 frames to one, since the eye cant really tell the difference, I think its called double cutting or something.

This 'gladiator' effect is *similar* to animation, it looks to me like they speed up action for brief moments, and hold on the image for about 8 frames or so occaissionally.
You could do this in premier (but it would take forever!)
I think the 'gain' trick works very well, for an action scene it would be excellent.
But the trick is to use it sparingly, dont overdo it.

There is a wicked trick for film-camera's called 'ramping' where you change the speed the film is travelling through the camera whilst you are shooting. This gives a similar (if not quite as slick) effect. Sam Raimi uses this in the hut in Evil Dead II, when Ashley is getting his pants scared off.
Things speed up and slow down very dramatic, like.

Cheers

[Matt-from-London]

It was possibe to get this effect in the battle scenes in the film Gladiator because the film was edited on computer. While filming a high shutter speed was used to prevent blurring. But instead of "projecting" the image at the standard rate, to achieve a slow motion effect, the images were played at the speed they were shot at, thus achieving this effect. It is possible to vary the "projection" speed to get the effect seen on many TV ads where action suddenly slows down mid shot (like the Renault Clio advert). You can try this yourself by editing your Super-8 homemovies with a computer.