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-   -   Shutter angle and shutter speed settings not really matching? (https://www.dvinfo.net/forum/sony-xdcam-ex-pro-handhelds/146066-shutter-angle-shutter-speed-settings-not-really-matching.html)

Michael Maier March 17th, 2009 07:53 PM

Shutter angle and shutter speed settings not really matching?
 
I was looking at the shutter angles today for the first time and I realized they don't match the shutter speeds. For example, in 24p, 1/48 is the normal shutter speed and that is equivalent to a 180° shutter angle. But while under shutter angles there's a 45° shutter angle setting available, in the shutter speed section there's no 1/192 for 24p which is the shutter speed equivalent to a 45° shutter angle in 24p. In 24p it jumps from 1/125 to 1/250. What's wrong? The only way to get a 45° shutter effect is to select shutter angle and you can't get that effect if you go by shutter speed? Or you can't get a 45° shutter effect at all and just either 1/125 or 1/250?
Quite confusing.

Another thing I don't get is how you control the shutter when in S&Q motion.

Tom Roper March 17th, 2009 09:39 PM

I don't have the cam in front of me but what you need is I think it's called ECS shutter, to get those in-between shutter speeds.

Doug Jensen March 18th, 2009 05:49 AM

Hi Michael,

I think you are making an issue out of nothing. Sony obviously just wanted to stick with nice round numbers when it chose which shutter speeds and shutter angles to provide on the camera.

It’s just a mathematical fact that angles and fractions aren’t going to have nice neat equivalents.

People who prefer using the Shutter Speed mode don’t want to see 1/192, 1/384, etc. as the options just to stay in sync with angles. What’s the point? If someone wants 45 degrees, then it is simple enough to choose 45 degrees. There is no need for an equivalent fraction.

To answer your second question about controlling shutter speeds in the S&Q modes, they really have nothing to do with each other. They are two separate settings. S&Q Motion controls how many frames are captured each second (frame rate), and the Shutter Mode controls the length of time that each of those frames is exposed (shutter speed). They are two unrelated settings so you just set the shutter speed the same way as you always do in the normal shooting mode.

There are a couple of limitations with S&Q:
1) The shutter speed cannot be slower than the frame rate.
2) You can’t use SLS and S&Q Motion simultaneously.

I hope that helps.

Doug Jensen March 18th, 2009 05:55 AM

Not that it makes any difference, but here's what the equivalents would be for 24P:

SLS 4 = 1440 degrees (try doing that with a film camera!)
SLS 2 = 720 degrees
1/24 = 360 degrees
1/48 = 180 degrees
1/96 = 90 degrees
1/192 = 45 degrees
1/384 = 22.5 degrees
1/768 = 11.25 degrees

I agree with Sony. I'd rather see 1/125, 1/250. 1/500 etc. as choices
I defy anyone to tell the difference visually between 1/384 and 1/500 anyway.

Michael Maier March 18th, 2009 07:44 AM

Hey Doug. Thanks for the reply. It's nice to see you around here.
I got your DVD a year ago when I got my EX1 and it helped me to get up and running with the camera. Great job you guys did there.

Quote:

Originally Posted by Doug Jensen (Post 1029590)
Hi Michael,

I think you are making an issue out of nothing. Sony obviously just wanted to stick with nice round numbers when it chose which shutter speeds and shutter angles to provide on the camera.

Yep, I thought so.

Quote:

Originally Posted by Doug Jensen (Post 1029590)
It’s just a mathematical fact that angles and fractions aren’t going to have nice neat equivalents.

It wouldn’t bother me to have the exact numbers, we are already talking fractions which are not round numbers anyways. The angles make sense to be round and they are in a film camera anyways, at least the most used ones.

Quote:

Originally Posted by Doug Jensen (Post 1029590)
People who prefer using the Shutter Speed mode don’t want to see 1/192, 1/384, etc. as the options just to stay in sync with angles. What’s the point?

I don’t see the harm. If you know what you are doing you probably know 45° is 1/192 and if you don’t know you probably won’t need that 1/192. In any case fractions are fractions in my opinion. But I see where you’re coming from. I just think this is a professional camera and the need to do it right needs to surpass the need to do it “pretty”. Just my opinion.

Quote:

Originally Posted by Doug Jensen (Post 1029590)
If someone wants 45 degrees, then it is simple enough to choose 45 degrees. There is no need for an equivalent fraction.

Ok, as long as this is how it works. Because I was afraid the angles were just for show and if you chose 45° it would be actually set at 1/250 etc. If 45° is a real 45° and is giving me 1/192 at 24p I’m fine with it.

Quote:

Originally Posted by Doug Jensen (Post 1029590)
To answer your second question about controlling shutter speeds in the S&Q modes, they really have nothing to do with each other. They are two separate settings. S&Q Motion controls how many frames are captured each second (frame rate), and the Shutter Mode controls the length of time that each of those frames is exposed (shutter speed). They are two unrelated settings so you just set the shutter speed the same way as you always do in the normal shooting mode.

Ok but my question was, for example, I’m shooting 40fps and want a 180° shutter. That is 1/80 for 40fps. This is not available under shutter speeds. So this means I can’t have a 180° shutter with 40fps or it means if I change to angle and set it to 180 the shutter will stay at 180° for any frame rate I select under S&Q and so when I’m at 40fps the shutter will adjust itself to 1/80 for a true 180° angle? This was my question. I know what a shutter is and what frame rates are. They are two very different animals. Sorry if I was not clear enough.




Quote:

Originally Posted by Doug Jensen (Post 1029593)
Not that it makes any difference, but here's what the equivalents would be for 24P:

SLS 4 = 1440 degrees (try doing that with a film camera!)
SLS 2 = 720 degrees
1/24 = 360 degrees
1/48 = 180 degrees
1/96 = 90 degrees
1/192 = 45 degrees
1/384 = 22.5 degrees
1/768 = 11.25 degrees
.

Yeap, for 24fps those are the equivalents. But when running the camera at different frame rates the shutter is also affected.













.

Michael Maier March 18th, 2009 08:58 AM

Quote:

Originally Posted by Tom Roper (Post 1029460)
I don't have the cam in front of me but what you need is I think it's called ECS shutter, to get those in-between shutter speeds.

I haven't needed to use ECS yet, but I'm not sure it's intended for that. It's a clear scan and in the manual it says the available setting values vary depending on the frame rate of the video format selected. I just tried to get 192 under 24p and I was able to though. Maybe Doug could elaborate on that Doug? Thanks.

Doug Jensen March 19th, 2009 06:21 AM

Quote:

Originally Posted by Michael Maier (Post 1029623)
Ok but my question was, for example, I’m shooting 40fps and want a 180° shutter. That is 1/80 for 40fps. This is not available under shutter speeds. So this means I can’t have a 180° shutter with 40fps or it means if I change to angle and set it to 180 the shutter will stay at 180° for any frame rate I select under S&Q and so when I’m at 40fps the shutter will adjust itself to 1/80 for a true 180° angle?
.

Hi Michael,
I'm Sorry didn't understand your original question, and you do bring up a very good point.

As Alister Chapman recently pointed out on another thread, using shutter angle is an easier way to keep your shutter speed consistent when you change video formats. I would expand on that and say that using angle is also the best way to keep the shutter speed consistent during S&Q shooting, too. If you want a 1/80th shutter at 40 fps, then use 180 degrees.

I can see why Sony didn't include a 1/80 setting because then they'd need a fraction for every other frame rate, too. How about 1/76 for 38 fps? 1/110 for 52 fps? It's so much easier just to put the camera on 180 degrees and be done with it.

ECS (Extended Clear Scan) is mainly designed to compensate for flickering you see on CRT computer monitors or other screens that have a different frequency than that of the camera. Personally, I wouldn't use it for anything other than that.

I'm glad you liked my DVD. Thanks.

Michael Maier March 19th, 2009 04:05 PM

Yeah, it seems using the shutter angle is a lot easier then. I will do that from now on. Thanks Doug.


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