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Old September 1st, 2020, 10:21 PM   #16
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Re: Is this a good way to fix this rolling shutter issue?

Oh okay, well how could it have been knackered in the editing? I watched the video but not sure how that applies to mine, or how I edited mine.

Another thing is, let's say the DP turned up the shutter speed. It was said before in a previous post that a high shutter speed is good because then you avoid rolling shutter. But is that true, or is a high shutter speed bad? I've never liked the high ones, myself, out of personal taste. If the video was at a higher shutter speed, then I suppose it got turned up without my knowledge, since I said to the DP that I wanted a 1/50 shutter speed while shooting at 23.976 fps, and say that it was 1/50 when he first selected it. Perhaps it got turned up later somehow, when he was operating the camera. At one point, he said the sun got too bright, even with the ND filters on, and so he said he was closing the aperture more. Perhaps he was actually increasing the shutter speed instead...
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Old September 2nd, 2020, 12:29 AM   #17
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Re: Is this a good way to fix this rolling shutter issue?

It seems to me that you plan things but never ever try to get really comfy with your equipment. Almost like you plan and plan but the shoot is the very first time you try things? The verticals should have been in your head and stability would have been my first thought, camera artefacts second. I would have tried that shot out weeks before to test that sideways track to see how smooth it was, and how I could make it better. Shots with obvious horizon, horizontal and vertical elements need special care, because camera movements, even tiny ones, are so obvious. Then you could try the adjustments to minimise the shuddering.

I have a hand held stabiliser. Never used it. If I get some spare time, I'll try some sideways shots with it and see how dreadfully it works with no skill level at all..
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Old September 2nd, 2020, 12:54 AM   #18
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Re: Is this a good way to fix this rolling shutter issue?

You won't notice any difference between 1/50 and 1/60, you need a bigger difference in shutter speed before it becomes noticeable.

I wouldn't get excited about the example you've given, if the audience notices anything you've got bigger problems than any rolling shutter or shutter speed artifacts.

You have to use your own eyes and make a judgment call on if an artifact is acceptable or not. On some occasions you may even want to use an artifact for dramatic effect.

With rolling shutting you need to take it on a shot by shot basis. The effect can be seen by panning your camera at ever increasing speeds in a location with verticals.
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Old September 2nd, 2020, 06:06 AM   #19
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Re: Is this a good way to fix this rolling shutter issue?

Oh okay. Well as far as getting comfortable with the equipment, it was the DP's camera and his gimbal, so for next time, should I arrange for more practice dates beforehand, perhaps with a DP?

Also, there are lots of movies that use verticals when panning or tracking with the camera though. Why are verticals bad now, since other movies in the past have used them, or what are they doing differently?
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Old September 2nd, 2020, 07:32 AM   #20
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Re: Is this a good way to fix this rolling shutter issue?

Skewed verticals are an artifact created by rolling shutters in digital cameras using CMOS sensors. Cinema cameras like the Arri Alexa and the RED have much lower levels, as do higher end video cameras, These cameras will have processing tricks in the camera to ameliorate the effect.

DSLR cameras tend not to do well in tests for this artifact, because it would add to costs in a price sensitive market For a camera in its class, the Panasonic GH5s does pretty well in this test, however, it's more a video camera than a stills camera.

Movies use either the very high digital cameras, which have a lot more processing power than your cameras or they shoot on film. A test for the Alexa's rolling shutter reports: "This level of distortion is not noticeable in practice; the design of the scanning process has largely eliminated the effect in this camera"
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Old September 2nd, 2020, 08:56 AM   #21
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Re: Is this a good way to fix this rolling shutter issue?

Quote:
Originally Posted by Paul R Johnson View Post
It seems to me that you plan things but never ever try to get really comfy with your equipment. Almost like you plan and plan but the shoot is the very first time you try things? The verticals should have been in your head and stability would have been my first thought, camera artefacts second. I would have tried that shot out weeks before to test that sideways track to see how smooth it was, and how I could make it better. Shots with obvious horizon, horizontal and vertical elements need special care, because camera movements, even tiny ones, are so obvious. Then you could try the adjustments to minimise the shuddering.
This.

The biggest learning lesson you should take away from this is when you lack experience with the equipment, filming technique, or location, you should do a dry run a week before. Obviously you don't always have the time, but you have expect that your chances of getting unpolished results and unanticipated issues increases.
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Old September 2nd, 2020, 05:03 PM   #22
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Re: Is this a good way to fix this rolling shutter issue?

Oh okay sure. I guess I just thought well if the DP/gimbal operator and actor are already available for that day, maybe we should just shoot it. But would a DP/gmbal operator find it insulting if you ask them to go out to a location and test out the shots, without the actors? Or is it perfectly normal to ask this of a DP/gimbal operator?

As for verticals being skewed, I always thought verticals were a good thing, such as in this video, where they talk about how verticals help polish a shot. He talkes about it at 1:15:


So he talks about how vertical objects during camera movement is a good thing, and I've always thought they helped look good during horizontal movement. But on a camera with rolling shutter, does that not apply? What if you pan the camera in a shot, and you can't help if there are vertical objects in the shot, what then?
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Old September 3rd, 2020, 12:53 AM   #23
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Re: Is this a good way to fix this rolling shutter issue?

Don't confuse the aesthetic of using verticals in a shot with an artifact created by the camera, they are different.

You can test the camera without going to a particular location, so you will know how prone the camera is to rolling shutter. in advance of the shoot.

By testing you'll know the limitations on how fast you can pan or move across verticals with a particular camera. If the skewing in the verticals are unacceptable at the speeds you want to use, you'll have to find a camera model that suffers less from rolling shutter. Although, if using a 1/100 or 1/120 shutter speed reduces it to an acceptable level, you may have to live with that on some shots. You have to be pragmatic at times, especially if you've got no or a very low budget.

Finding out on the day of the shoot isn't good planning, especially since you now know that rolling shutter exists.

I wouldn't worry about the example in your short, it's pretty acceptable.
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Old September 3rd, 2020, 02:25 AM   #24
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Re: Is this a good way to fix this rolling shutter issue?

What I find simply amazing here is that you use the term DP/Gimbal op when that does indicate to me a person that understands the equipment, the implications for movement, the technical reasons problems appear and the ability to spot problems and errors when shooting, and solve them. You would NEVER insult a professional and competent operator by questioning their ability like this. What you would do is tell them the shot, and ask if the equipment can do it OK? If they say yes, it will. If they say yes and clearly the equipment is unable to do it, then they're rubbish, and deserve the title trainee camera op, not your one!

When I engage somebody to light, their track record tells me I leave them alone and they'll do what I want. Same with sound. Your team sound like very unusual professionals, and your role as Director or Producer, or whatever you style yourself this week to be does not include being a camera supervisor. We've told you all this many time before. I suspect that you will insult them, but frankly, if they need to test and practice a simple blend of shot style and camera type, something is not quite right. Proper DP people will say "I can't do that withe the rubbish camera you are forcing me to use - we need an XXX if you must have that shot"

Brian pointed out the different context in that clip - how did you misunderstand it?
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Old September 3rd, 2020, 06:11 AM   #25
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Re: Is this a good way to fix this rolling shutter issue?

Oh okay thanks. I didn't misunderstand the context I don't think, I just meant to ask, if vertical is good, like some pointed out, how do you make it work on a camera without a global shutter? However, I read that the Sony A7s II is sensitive for rolling shutter, so perhaps I should use a different camera next time then, or have a DP use a different one.
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Old September 3rd, 2020, 06:34 AM   #26
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Re: Is this a good way to fix this rolling shutter issue?

You have to know the limitations of each camera model and avoid situations that will cause issues. You can check these through testing, if a camera is sensitive to rolling shutter you should either find another camera or change your shots.
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Old September 3rd, 2020, 11:17 AM   #27
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Re: Is this a good way to fix this rolling shutter issue?

Most tools have difficulty with certain processes - this is exactly why professionals need to be able to analyse and produce conclusions followed by proper plans. In the forces they refer to it as the five P's.
Proper Planning prevents piss poor performance and this has always held so true for me. The better the plans, the better the end result!
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Old September 3rd, 2020, 01:07 PM   #28
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Re: Is this a good way to fix this rolling shutter issue?

gimbal op for his movies is a friend who owns a cheap gimbal that they can throw someone's camera on that they've borrowed for the day. I laugh that you wouldn't know that dslr/mirrorless cameras might have problems with rolling shutter and verticals.
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Old September 3rd, 2020, 02:55 PM   #29
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Re: Is this a good way to fix this rolling shutter issue?

Which verticals Pete? Vertical verticals or vertical Verticals? I suspect Ryans using the wrong ones and getting 90/270 issues on his horizontals.
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Old September 3rd, 2020, 04:20 PM   #30
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Re: Is this a good way to fix this rolling shutter issue?

Oh by verticals I meant objects that are sticking vertically out of the ground. But if mirrorless cameras have problems with rolling shutter, perhaps my next camera investment should be a mirror camera therefore maybe, if it helps avoid it?
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