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Sony VX2100 / PD170 / PDX10 Companion
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Old March 8th, 2003, 06:35 PM   #1
Liam Donnelly
 
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Shooting with a strobe light and PD150

Will many technical problems / difficulties arise if I try to shoot a fast strobe lighting effect with PD150? what settings should I use? The light will be white and really strong. There will also be mirrors involved.

Thanks.
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Old March 8th, 2003, 08:50 PM   #2
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leave steady shot off or your picture will jump in time with the strobe.
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Old March 11th, 2003, 02:41 AM   #3
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Strange you should say that Mike. The Sony VAP OIS is purely dependant on camera movement. As such it works in total darkness and/or zero contrast. Strobes won't affect it at all as far as I can see.

But strobes certainly will effect the exposure. I've shot a lot of disco sequences with the VX2k and I always lock down the exposure for the available light. Let the strobes over-expose, that way you add sparkle to the footage.

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Old March 11th, 2003, 05:27 PM   #4
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It may be strange but it is true. I have no idea what little bit in the camera is sensitive to it but I can show you lots of footage of police car lights where the image jumps in sync with the strobes.

It may be electrical interference which we know is a problem with the PD150 or something else. But it happens. I was about 4 feet from the light bar when this happened.

There are at least 5 known problems with the OIS in the PD150:

1. It is sensitive to radio waves and will move the image in the frame.
2. It causes internal reflections of bright lights.
3. It causes the image to move.

The other problems have to do with having the OIS on when walking. It can cause the image to snap from side to side.

The other is that OIS will fight a pan or tilt movement and make the first and last bit of that movement a little strange.

BTW, I don't know whether the OIS sensor are image dependent (sampling the image on the CCD) or are accelerometers. If they are image dependent, then the OIS will not work in full black or zero contrast environments (but then how would one know?).
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Old March 12th, 2003, 03:11 AM   #5
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Very interesting post Mike. Are you in the USA? I ask because I take "strobes" to mean electronic flash whereas in England strobes can be tungsten filaments that simply switch at varying frequencies.

However - to the VX2k's Steadyshot. I didn't know about its sensitivity to radio, but I hope you're not including radio mic receivers in this.

Reflections in bright lights - yes. It is after all four glass surfaces, and there's no way the extra flare won't be seen. If you shoot straight into the light and wobble the camera you can see the Steadyshot elements floating independently of the other (fixed) elements on replay. Just watch the lens flare highlights.

As you say, SSS causes the image to move, and it's just detectable that there's a slight stickyness to the start of pans. Nothing like as bad as EIS systems though, and for most people it's very hard to spot. I forgive it its slight weaknesses; OIS is as close to magic as you or I will see.

The OIS mechanism is purely camera movement dependant Mike. The big rectangular box under the front element (exactly as on the GL2 and the XL1s) houses the stabilisation pistons and their electronics. Go into a max aperture, max wide-angle, max gain up situation. It's pretty dim, yes? Switch the SSS on and off and you'll see that it happily caries on working, whereas the autofocus (image dependant) has given up ages ago.

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Old March 12th, 2003, 11:16 AM   #6
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<<<-- Originally posted by Tom Hardwick : Very interesting post Mike. Are you in the USA? I ask because I take "strobes" to mean electronic flash whereas in England strobes can be tungsten filaments that simply switch at varying frequencies.

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In the USA, the term 'strobe' is meant to describe an electronic flash.
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However - to the VX2k's Steadyshot. I didn't know about its sensitivity to radio, but I hope you're not including radio mic receivers in this.

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Only transmitters and it doesn't take much of a transmitter to cause the problem.
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Reflections in bright lights - yes. It is after all four glass surfaces, and there's no way the extra flare won't be seen. If you shoot straight into the light and wobble the camera you can see the Steadyshot elements floating independently of the other (fixed) elements on replay. Just watch the lens flare highlights.

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I find it curious that they manage to handle reflections off of other glass surfaces inside the lens. And my multi-coated filters don't seem to cause any problems either. Granted, they are not at an angle with regard to the optical axis as is the OIS.
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As you say, SSS causes the image to move, and it's just detectable that there's a slight stickyness to the start of pans. Nothing like as bad as EIS systems though, and for most people it's very hard to spot. I forgive it its slight weaknesses; OIS is as close to magic as you or I will see.

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Magic is not my point. The point is it causes an artifact and users need to be aware of it before it effects their footage. It is possible, if accelerometers are used in the camera, they could be used just as effectively (with computation) to soften the abrupt start/stop. Maybe even offer several different programmed modes so we could chose how the OIS offers assistance in different shooting situations.
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The OIS mechanism is purely camera movement dependant Mike. The big rectangular box under the front element (exactly as on the GL2 and the XL1s) houses the stabilisation pistons and their electronics. Go into a max aperture, max wide-angle, max gain up situation. It's pretty dim, yes? Switch the SSS on and off and you'll see that it happily caries on working, whereas the autofocus (image dependant) has given up ages ago.

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You are talking about observed camera behaviour. That is not what I questioned. The question is whether they use accelerometers or the CCD to detect camera motion.

The difference between no detectable image detail as you stated in your first post and the latest, where you talk about a 'dim' image is of major difference (in trying to answer the question).

In a dim visual field, the camera could indeed be using the CCD signal. In a blank visual field, the CCD would be of no use at all but how would we detect the operation of the OIS to confirm this? Maybe through the use of a microphone as mentioned in another recent post on this forum.

The difference between the use of a multi-axis accelerometer and the CCD could be of major importance if we want a system that will always differentiate between movement in a scene and movement of the camera. Of course they could be using a combination of both.

BTW
I think the OIS in my old Hi-8 camera, a Sony TR-CCD3300 is effectively at least as good if not a bit better than that in my PD150. I have some really good footage taken by myself as a friend drove me down an English country road in a Mini outside of Cheltenham. The apparent movement is much 'softer' than my footage taken in the passenger seat of a Police Car here in Northern California as we took a Code 3 drive (fast with lights (strobes) and sirens) through town.

I'd say it was better except I have to recognize that the PD150 is longer, larger, and less well-balanced than the Hi-8 camera.

Actually, my PC110 with its EIS is effectively just as good as the PD150 due, I think, to its very small size and my ability to cushion it from shock so much better than I can the PD150.

BTW, BTW
One does have to differentiate between Steady Shot and Super Steady Shot as they don't or didn't always differentiate between EIS and OIS cameras.
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Old March 12th, 2003, 03:56 PM   #7
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You're right - Sony don't go to pains to point out which of their stabilisation systens are optical and which are elecrtonic. My TR2000 Hi8 had just Steadyshot (not "super") yet was a VAP design with the lens-lump to house the pistons.

My Panasonic MX300 has OPTICAL in big letters, but I feel this was more to alieviate buyers fears that they might be getting the dreadful and degrading EIS that Panasonic used for many years.

>You are talking about observed camera behaviour. That is not >what I questioned. The question is whether they use >accelerometers or the CCD to detect camera motion.

I take it they only use accelerometers as with your ear pressed to the VAP operating enclosure you can hear it work even with the lens cap on.

tom.
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