My thoughts on the AF100 after 1.5 days

Your shutter speed is set by the dial on the back. You can choose a fractional speed (i.e., 1/250th or 1/24) or you can select the Syncro Scan speed (which is located between the fastest and slowest shutter speeds).
 
Okay, that is what I thought. It seems some people thought the selection would be different depending on what mode you were in, but they are the same for me no matter which mode (FILM or VIDEO).

With Syncro Scan, how do you change the value on the fly? Only through the menu?
 
So they changed the way it works compared to the HVX? I remember in the HVX if you were in VIDEO CAM mode it was 1/48, 1/60, etc. And in FILM CAM mode you adjusted the shutter as degrees. Now it's 1/48, 1/60, etc in both VIDEO CAM and FILM CAM modes, but you can choose SYNCRO SCAN and then adjust in degrees in both modes to override the other setting? Am I getting this right?
 
So in 24fps I see 1/24, 180.0d, 1/60, 1/120, 1/250, 1/500, 1/1000, 1/2000. There is no 1/50 listed. This is in both FILM and VIDEO mode. When 180.0d is selected, you can hit the DIAL SELECT again and go into setting the synchroscan in 0.5 degree increments.

I am not sure why 1/50 doesn't exist in there?!? (It is listed in the manual)

While I can set the exact shutter speed I want with the syncroscan feature, at 0.5deg changes it is too much effort to cycle through the settings. I don't see myself using this OTHER than selecting something between 1/24 and 1/60 that I like using. I still contend adding some additional settings in there would be better.

Interestingly, the manual says adjust the IRIS and shutter speed for exposure. Those silly engineers :) Also, I like that for long exposure times, it says red, blue, green or white pixels are normal. In other words, if you see a hot pixel, deal with it! :)

So no, sounds different than the HVX.
 
There's no reason for 1/50th on a US camera. Well, maybe not "NO reason," but 1/48th is the shutter speed you'll want to use at 24 frames.
 
Obviously, Barry is right; leaving the shutter at 1/60 and fine tuning exposure with the iris is the safest/most orthodox way to go. However, with my HVX, I fly in the face of this sound advice all the time; I actually have scene files set to 120 degrees, 180 degrees, and 240 degree shutter, so I can quickly flip between them to finesse exposure without compromising my preferred f-stop. As long as there's no kung-fu or car racing going on in the shot, the difference in motion blur is basically imperceptible; it's only when you start to approach a 90 degree shutter or beyond, to me, that things get noticeably staccato. (Just my opinion and admitedly unorthodox way of working; I think I may miss having this ability with the AF00, but the large sensor is more than worth it!)

Of course, as Barry says, you have to watch out for flicker when ballasted lights are involved, but that's pretty much always something to keep in mind!
 
Mike@AF said:
So they changed the way it works compared to the HVX? I remember in the HVX if you were in VIDEO CAM mode it was 1/48, 1/60, etc. And in FILM CAM mode you adjusted the shutter as degrees. Now it's 1/48, 1/60, etc in both VIDEO CAM and FILM CAM modes, but you can choose SYNCRO SCAN and then adjust in degrees in both modes to override the other setting? Am I getting this right?
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No, it works exactly like the HVX/HPX170 do. FILM CAM = syncro scan displayed in degrees. VIDEO CAM = syncro scan displayed in fractions.
 
grimepoch said:
So in 24fps I see 1/24, 180.0d, 1/60, 1/120, 1/250, 1/500, 1/1000, 1/2000. There is no 1/50 listed. This is in both FILM and VIDEO mode. When 180.0d is selected, you can hit the DIAL SELECT again and go into setting the synchroscan in 0.5 degree increments.

I am not sure why 1/50 doesn't exist in there?!? (It is listed in the manual)
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1/50 is the default shutter speed for 24p and 30p (and 25p) when you turn the shutter off. If you're actively selecting a shutter speed, it'll choose from those you listed. When you turn the shutter off, it goes to the default speed, which is 1/50 for progressive or 50i, and 1/60 for 60i or 60p.

So no, sounds different than the HVX.
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It is exactly the same as the HVX.
 
bkmvincent said:
There's no reason for 1/50th on a US camera. Well, maybe not "NO reason," but 1/48th is the shutter speed you'll want to use at 24 frames.
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ONLY if you know exactly what you're doing and exactly what the lighting conditions are! 1/48 can screw you over if you're shooting under magnetic-ballast HMI's or fluos, or dimming LED's, or stadium lights, or streetlights.

Seriously, people, join in with me on this -- this "1/48th for 24p" mindset is potentially damaging to your footage and it really needs to be educated out of folks. 1/48 is great for film or CCD, but for CMOS it is NOT what you want to be using!
 
Barry_Green said:
ONLY if you know exactly what you're doing and exactly what the lighting conditions are! 1/48 can screw you over if you're shooting under magnetic-ballast HMI's or fluos, or dimming LED's, or stadium lights, or streetlights.

Seriously, people, join in with me on this -- this "1/48th for 24p" mindset is potentially damaging to your footage and it really needs to be educated out of folks. 1/48 is great for film or CCD, but for CMOS it is NOT what you want to be using!
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+1 (unless you are actually shooting 24fps and not 23.98 on something like a RED, then 1/48 is ok)
 
Brian@202020 said:
+1 (unless you are actually shooting 24fps and not 23.98 on something like a RED, then 1/48 is ok)
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Red is subject to the exact same limitations. Put a Red under a magnetic-ballast HMI at 1/48, and you're going to see scrolling waves in the footage. Same thing with dimming LED's, or stadium lights, or magnetic fluos. Red is a CMOS camera, there's nothing magical about it, it's subject to the same restrictions as everything else is.

Only major difference is that likely a shoot that can afford a Red, would also be using electronic-ballast HMI's and electronic-ballast high-frequency fluos, so they just wouldn't encounter the problem because they would be shooting with equipment that doesn't generate the problem. But that's the same with an AF100 or a GH1 or a 7D too, if you used them with electronic-ballast lights they wouldn't have waves either.

The problem is shutter speed and ballasted lights on CMOS sensors, regardless of who makes the CMOS sensor. The only "safe" shutter speeds are those that are divisors of twice the line frequency -- so in 60Hz territories that means 1/120, 2/120, 3/120, 4/120, and 5/120. In 50Hz territories that means 1/100, 2/100, and 4/100. Those are the "CMOS safe" shutter speeds. Any other shutter speed is subject to showing the effect. Period. And the only way to avoid it is to a) only use the approved shutter speeds, or b) avoid ballasted lights.
 
Brian@202020 said:
I was just referring to 24p and how RED can shoot actual 24p and not only 23.98. At 24p 1/48 shutter is ok.
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But it's still a CMOS sensor and it is still subject to all the same problems. 0.1% speed difference doesn't change that. It's true that the Red can shoot at 24.000 instead of 23.976, but it's still going to have the problems of scrolling bars in its footage, if shot under those types of lights, unless they use 1/60th, or 1/40th, or 1/30th, or 1/24th shutter speeds. 1/48 will cause the bars.
 
Barry_Green said:
But it's still a CMOS sensor and it is still subject to all the same problems. 0.1% speed difference doesn't change that. It's true that the Red can shoot at 24.000 instead of 23.976, but it's still going to have the problems of scrolling bars in its footage, if shot under those types of lights, unless they use 1/60th, or 1/40th, or 1/30th, or 1/24th shutter speeds. 1/48 will cause the bars.
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I was unaware of this. I thought it had to do with the shutter speed and how well it'll pick up on a CMOS sensor if you were off and not the 60Hz/50Hz thing. I might have to look at some old footage and see if there is anything going on. I know I've been screwed a few times with random framerates and random shutterspeeds in metallic HMI situations early on in my career, but I always thought 24fps and 1/48 would work even with a CMOS chip in 60Hz land.
 
No, I tested it on my Red One, and definitely it is subject to the same issue. Simply put, you should never use 1/48th unless you know exactly what kind of lights you're shooting under and you know for certain that they will not cause a problem. Your shutter speed HAS to be a divisor of double the line frequency, in order to avoid the scrolling bars. The closer it is to the line frequency the less noticeable the bars will be (which is why 1/48 produces very mild bars, whereas 1/500 produces horribly obvious bars) but they'll still be there.

You can change the frame rate all you want, with no worries. It's all about the shutter speed, as to whether the bars will show up or not.
 
I'm trying to think if I have ever shot my RED under magnetic ballast HMI's. I know I did with my HVX a few years back but you said it's less noticeable with CCD's.
 
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