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Why not increase shutter speed? Why use NDs? (Seriously)
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  • Shooting in a faster shutter has advantages for me and still allows a moderate amount of motion blur and sharp images. Much of my footage would contain too much motion blur if i shot at 1/60. For example, this video below I shot last weekend from the back of a jetski on GH1, 14-140kit, 720p 60fps at 1/125 shutter, video was edited and exported for vimeo at 30p. As you can see, still has a pleasing amount of motion blur. ( I did miss pressing that damn tiny lock exposure/focus button a few times....big fingers..small button) :-)

    Powerade 20 Beaches Ocean Classic

  • @Rambo Isn't that still (almost) a 180 degree shutter since you were shooting at 60p, which would give you the standard 'natural' motion blur? I think what the OP was talking about is the usage of shutter to control exposure, rather than ND, which would mean varying shutter speeds throughout a shoot and real time playback speeds. And that's what people are having a hard time accepting as an approach. Your approach, on the other hand, is more conventional. Very nice stuff, but the way. Well captured and presented!

  • Actually for 60p a shutter of 1/60 is still recommended for natural motion blur, normally you would use 1/120 if intending to slowmo in post. I do sometimes shoot in variable shutter mode as it allows faster stepless exposure compared to aperture changes on the fly. In my game it's not so important to stick to guidelines..... as it's live action, one take, getting the content is a priority. Major broadcast accept it, I just had a 30 min show featured on NBC Universal Sports Network that consisted entirely of PAL, NTSc footage shot on GH1/2 at shutters between 1/50-1/500, but I appreciate most people on PV are from film backgrounds and follow the industry guidelines .... outside of that, plenty of news, sports and docs get shot on auto mode. Thanks for the kudos.

  • Odd, I thought 1/120 was what you used for 60p too.

  • I used to follow that "stick to a shutter of 1/50 rule" I personally disagree with that, film however you want. Whatever looks great to you. I haven't shot with a shutter speed of 1/50 in two years I always keep my shutter speed at like 1/100 or higher. I have never used a ND filter in my life and really think about the GH2 isn't going to produce the same motion blur you see in cinema cameras regardless if you stick to the 180 degree rule or not

  • @Vicharris Odd, I thought 1/120 was what you used for 60p too.

    Check any post by Barry Green on DVinfo on the subject, he recommends 1/60 for 60p for regular capture or 1/120 if slowmo is desired in post. :-)

  • @Rambo Ah, I guess I've never used 60p for anything other than slow mo. Guess that explains it. We work in different worlds my friend :) And yep, for the type of work you do it's all about getting the shot no matter what!

  • @DeShonDixon Here's where personal taste and styles differ. I personally can't stand when there's barely any blur. Looks like cheap video or soap opera stuff and I can see it easily. Makes me click X right away if it's narrative work. And as the shutter goes for the GH2, I've never shot with 1/50th as I still think it looks like crap. I shoot with 1/40 or even 1/30 if I can get away with it and there's zero or little movement.

  • Questioning one's assumptions is a good way of creating new experiences, but also it brings about the unfamiliar, which we know from the past, offends the eye of the traditionalists. We rarely learn from the past ;)

    Btw @Rambo really nice work! :)

  • @vicharris I always shoot with higher shutter speeds and i've seemed to never have a problem with any of my footage looking like soap opera from my experiences. If anything they seem more filmic to me. I avoid 1/50 or anything lower cause I feel they look like cheap video or soap opera stuff to me, but its all personal preference everybody sees things differently.

  • shooting in 25p and without a set up of lights

    I use 1/25 most of the time in lowlight, for not increasing the iso tooo much (as it decreases de dynamic range and increases the noise, i never go upt of iso 1000), but with 1/25 there is a decrease in resolution (at least to my eye), so 1/50 whenever i can

    in daylight i try to use 1/50, but also 1/100 if there is no movements on the shot (i try to avoid the use of the nd filter that i have), because if there is no big movements, there is no need of motion blur

  • btw thinking about it i would very much prefer to have control in post over the motion blur (to use it just like in animation, to increase the emotional intention of a movement), but as of right now i believe there is simply no workflow that is useful, just plain painful and only after tons of work one can get more expression out of the blur

  • @DeShonDixon Well, there you have it :) Even though that defies the laws of film and all known standards, it looks the opposite to you and I guess that's all that matters.

  • @Rambo That's news to me! Math tricked me and told me 1/60 would be 360 degree shutter, but I admit my experience with 60p and it's conventions is quite low.

    Either way, I just got schooled by a video beach bum! =)

    And I mean that in the most jealous way possible. I'm probably in the warmest climate in Canada right now but the sun is still down by 4:45pm this time of year. Thanks for the virtual sunshine!

  • @Jumo, Either way, I just got schooled by a video beach bum! =)

    Haha....that makes Barry Green a "beach bum" too, not sure he would be happy with that. :-) but he would get this question re 60p 1/60 at least one a week.

    You know, its funny how things work, in the GoPro World we actually ADD ND filters to lower the shutter speed so that it eliminates most of the jello wobbles caused by the fast shutter and hi Freq vibes, also to blur out propeller blades in the frame.

    Time to head back to the beach.:-)

  • This discussion should split in at least 3,

    • "How I like my motion blur"

    • "HELP! Why do I have those dark lines going in and out of my image??"

    • "Things you should never ask on a film set"

  • 120 shutter for 60fps has always been mechanically locked-in for movie cameras (those which have a 60fps or variable setting). the Bolex reflexes had a variable shutter which was seldom used although the manual suggested, "In dazzling light, such as snow and water.."

    We used that variable shutter lever to do in-camera tricks like fades and double-exposures. Nobody I know used it to reduce exposure time - the tiny ND filters between the lens and the film gate did the trick.

  • At 1/50, your footage will indeed appear more "jerky" -- but it'll also exactly match the motion of film shot at 25fps on a movie camera with a 180-degree shutter.

    At 1/25, the motion will be substantially more blurred, and not film-like. 1/50 gives you the look and motion rendition of film.

    Barry Green, in response to the question, "why is it not better to film 1/25th of a second at 25p?" (about a slower shutter speed but all I could find on DVinfo)

    http://www.dvinfo.net/forum/canon-xl-gl-series-dv-camcorders/39506-differences-between-shutter-fps.html

  • If there has been a big breakthrough with motion blur, IQ, and other things using a higher shutter speed, we'd know about that. 180 degree is normal motion blur, I'm sure there have been a lot of tests to settle on that.

    That would make 60fps with a 120(or 125) degree shutter. Working in and with news, that was the norm. 2 and a Half Men uses 3 35mm Panavisions all at 60fps and 180 degree shutter, 1/120.

    I guess shutter speed is a choice for a certain look. So do what you please.

  • @nomad says:

    I was once asked to fix a daylight shot of dancers that was shot with 1/100 by mistake and it was a nightmare of masking

    As it happens, I often use a fast shutter specifically to obtain stills later. As was said in other threads, you cannot keep up a burst mode for half an hour (and why would you want to sort through all those stills), whereas a well-chosen grab from a 60fps/250+ video can produce a winner shot of dance, sport - and even just that right smile!

    Naturally, I have run these videos at normal speed. Fast movement becomes ridiculous; at 24fps/200 (stage lighting can be low), sometimes dancer's step happens between frames and never appears within a frame.

  • Why should you use ND instead of shutter? hm... No absolute (and there will never be) but a bit of a clue:

    1) Realistic Motion blur in post looks unrealistic if it has to be on an entire image. (In 3D we generate a Velocity pass which calculate the movement of every pixel making it more flexible and accurate to produce a realistic motion blur but from a plate it is very hard and the few softwares that does it are kinda... wip at the moment). 2) It takes a lot of time to the R&D to nail the thing and even when they get it, the result is far from a real motion blur. 3) Rendering can become easily inaccessible for the latest i7 and could require more than 32go ram.

    The motion blur added in post that I'm aware in the VFX industries are mostly for green screen since you do not want motion blur and a few other cases that would require rotoscopy by breaking the image and re-making the motion blur (and it's a pain in the ass to do this) but otherwise you tries to do everything on set.

    If you lack the money (no money for an ND filter but money for an i7 is kind of ironical) for a ND filter and are willing to extend your time in post then I see no reason that should stop you. But motion blur in post can quickly be categorized as Advanced compositing and unless you've studied the thing very carefully you'll have very hard time.

  • Just found this topic and have to agree with the op. I have always followed the 180 degree shutter rule, both in my professional and personal work to make it look what we would call 'filmic'. This has given me serious headaches in the past, especially in run and gun scenarios when trying to constantly control exposure by scrolling an nd filter around to make sure your scene is not blown out or too dark.

    In controlled environments it is easy to use an nd but run and gun, when you are constantly moving around, changing from dark to light scenes an nd filter makes things impossible.

    I in these instances would switch to an automatic mode like Shutter priority which would give me a constant 1/50 shutter at the expense of no DOF or put the camera in A mode so I get the shallow DOF but at the expense of probably high shutter speeds.

    I have used rsmb pro in the edit and it works very well in normal action scenes. Yes it does struggle with a lot of action and causes smearing but to me it is another useful TOOL...and thats whats important, what tools you need to make your work easier.

  • A faster shutter speed will not reduce rolling shutter, as the rolling shutter always reads the sensor out at the same speed regardless of shutter speed. They are entirely separate processes. In fact, a slower shutter speed can often improve the look of rolling shutter effects by hiding them with motion blur.

  • I use old Leica R lenses on the GH4. I try to keep my aperture as wide as possible.

    Shooting with a 180 degree shutter does indeed create the most pleasing representation of motion. Unfortunately, I have found that all of the ND filters (B+H, Formatt, etc.) that I have tested result in an unacceptable loss of image quality. I have not tested the Heliopanbut I would be surprised if I did not get similar results at the higher grades (.9 and above).

    I therefore shoot with high shutter speeds. (The GH4 goes up to 1/10,000.) The out of camera look is unacceptable of course. I add blur in post with ReelSmart. So far it provides the representation of motion comparable to shooting with a greater shutter angle.

    I may indeed find scenes that contain motion that is incompatible with this approach and may need to shoot with ND filters at a true 180 angle. But so far I have not dealt with such a scene.

    For dailies, the blur can be added almost instantaneously -- once the 4k shot is brought down to FHD. So no one need see the footage without the blur.

  • @Noelpuppet - try the Genustech Eclipse vari ND. Yet to have a color cast problem.