EX1 Fails Strobe Test

Vincent Oliver · December 28th, 2010, 01:47 AM

I too have experienced half frame flashes, to get straight to the point I am not sure what all the fuss is about. Full frame flash or half frame flash on your footage etc. it all looks bad. It's just one of those facts of life we have to accept. I have never had a client complain about a partial flash frame and I very much doubt if anyone else has, unless of course it is during an expensive production involving actors and a hired location.

I know it is annoying, but then if you are doing a wedding then you should point out to the bride and groom before the event that flashes could affect some of the frames, then it is their responsibility to ask guests not to use flash. However, the paparazzi effect of lots of flashes going off, often adds to the buzz of a successful wedding coverage.

Happy New Year to you all

Brian Rhodes · December 28th, 2010, 03:28 AM

Patrick I did this Helicopter shoot in Vegas last year. I did not have any issues with my EX1...I am also doing a shoot of the downtown area in Houston soon.
YouTube - Bellagio fountains and Vegas Helicopter Video

Alister Chapman · December 28th, 2010, 03:33 AM

I have not used the 350 in a chopper but I have used EX1's and 3's in choppers and planes and provided you isolate the camera from direct vibration (ie camera not touching airframe) I have found them to be fine.

I've been using EX's for 3 years and rolling shutter has never caused a problem so bad that I can't use the footage. With care even thunderstorms and lightning can be shot successfully by using 25/24P an either no shutter or a 2 frame shutter. Sure I wish I didn't have to do that but all the other EX benefits over my previous small cameras outweigh the down side of the rolling cmos shutter.

Paul R Johnson · December 28th, 2010, 05:36 AM

The post that inspired this doubt was somewhat clumsy in the way it 'tested' the camera. It says

Quote:

If you take white strobes firing at precise, regular intervals, and shoot it with a camera recording video frames at precise intervals, then you should have a regular pattern of flashes, not a seemingly random series of flashes

The camera is shooting at precise intervals, but the strobe from a police zenon flash unit? There's no timing at all to speak of - it charges through a capacitor/resistor and fires - you don't get any timing accuracy whatsoever? Why would it need to be synced to a common reference? That's why when you see multiple strobes all working together the pattern constantly shifts. Or have I totally misunderstood the complaint in the report?

Serena Steuart · December 28th, 2010, 05:52 AM

The complaint is a nonsense --- the strobe was not synchronised with the camera frame rate and often the shutter would have been closed when the strobe fired. If it had been synchronised with the camera then it would have been possible to arrange all flashes to fire when the shutter was closed, so then you would see no flashes at all.

Patrick McLoad · December 28th, 2010, 10:27 AM

Thank you Alister, that makes me feel abit better. Aerials are hard enough to pull off without worrying about shutter artifact.

My usual mode of camera work is with the sliding door tied back with me sitting on the floor with legs out the chopper, camera on my shoulder. I rarely have the luxury of using a Tyler mount. I recall using an expensive-to-rent image stabilizing lens many years ago, but it seemed to be a pain-in-the *** to use. Seems that without full axis gyro stabilization, you're simply at the mercy of the pilot and the winds. Some days diamonds, other days coal.

Thanks.

Patrick McLoad

Patrick McLoad · December 28th, 2010, 10:35 AM

Thanks Brian, that looked good with no apparent shutter problems.

Patrick McLoad

Alister Chapman · December 28th, 2010, 11:05 AM

You might want to consider hiring a pair of kenyon gyros. They can work minor miracles. Hope you have a proper dispatchers harness.

Patrick McLoad · December 28th, 2010, 11:14 AM

Thanks, will look into them. We have a motion-picture supply / rental outfit here in Houston called Texcam, and they can probably rig up a set for me. I had heard of these but had forgotten.

Yes, of course, the chopper crew wouldn't let me off the ground without ALL safety harnesses in place and of the right type. I personally own 4 full-body harnesses and shock absorbing lanyards.
I also tie-off the camera.

Thank you.

December 28th, 2010, 01:47 AM	#16
Vincent Oliver Trustee Join Date: Sep 2004 Location: Chislehurst, London Posts: 1,724	I too have experienced half frame flashes, to get straight to the point I am not sure what all the fuss is about. Full frame flash or half frame flash on your footage etc. it all looks bad. It's just one of those facts of life we have to accept. I have never had a client complain about a partial flash frame and I very much doubt if anyone else has, unless of course it is during an expensive production involving actors and a hired location. I know it is annoying, but then if you are doing a wedding then you should point out to the bride and groom before the event that flashes could affect some of the frames, then it is their responsibility to ask guests not to use flash. However, the paparazzi effect of lots of flashes going off, often adds to the buzz of a successful wedding coverage. Happy New Year to you all __________________ Eyes are a deaf man’s ears. Ears are a blind man’s eyes

December 28th, 2010, 03:33 AM	#18
Alister Chapman Inner Circle Join Date: Dec 2005 Location: Bracknell, Berkshire, UK Posts: 4,957	I have not used the 350 in a chopper but I have used EX1's and 3's in choppers and planes and provided you isolate the camera from direct vibration (ie camera not touching airframe) I have found them to be fine. I've been using EX's for 3 years and rolling shutter has never caused a problem so bad that I can't use the footage. With care even thunderstorms and lightning can be shot successfully by using 25/24P an either no shutter or a 2 frame shutter. Sure I wish I didn't have to do that but all the other EX benefits over my previous small cameras outweigh the down side of the rolling cmos shutter. __________________ Alister Chapman, Film-Maker/Stormchaser http://www.xdcam-user.com/alisters-blog/ My XDCAM site and blog. http://www.hurricane-rig.com

December 28th, 2010, 11:05 AM	#23
Alister Chapman Inner Circle Join Date: Dec 2005 Location: Bracknell, Berkshire, UK Posts: 4,957	You might want to consider hiring a pair of kenyon gyros. They can work minor miracles. Hope you have a proper dispatchers harness. __________________ Alister Chapman, Film-Maker/Stormchaser http://www.xdcam-user.com/alisters-blog/ My XDCAM site and blog. http://www.hurricane-rig.com

December 28th, 2010, 03:28 AM	#17
Brian Rhodes Major Player Join Date: Nov 2005 Location: Houston, Texas Posts: 753	Patrick I did this Helicopter shoot in Vegas last year. I did not have any issues with my EX1...I am also doing a shoot of the downtown area in Houston soon. YouTube - Bellagio fountains and Vegas Helicopter Video

December 28th, 2010, 05:52 AM	#20
Serena Steuart Major Player Join Date: Jun 2006 Location: Studio Alnitak, Melbourne, Victoria, Australia Posts: 640 Images: 3	The complaint is a nonsense --- the strobe was not synchronised with the camera frame rate and often the shutter would have been closed when the strobe fired. If it had been synchronised with the camera then it would have been possible to arrange all flashes to fire when the shutter was closed, so then you would see no flashes at all.

December 28th, 2010, 10:27 AM	#21
Patrick McLoad Regular Crew Join Date: Mar 2003 Location: Houston, Texas Posts: 52	Thank you Alister, that makes me feel abit better. Aerials are hard enough to pull off without worrying about shutter artifact. My usual mode of camera work is with the sliding door tied back with me sitting on the floor with legs out the chopper, camera on my shoulder. I rarely have the luxury of using a Tyler mount. I recall using an expensive-to-rent image stabilizing lens many years ago, but it seemed to be a pain-in-the *** to use. Seems that without full axis gyro stabilization, you're simply at the mercy of the pilot and the winds. Some days diamonds, other days coal. Thanks. Patrick McLoad

December 28th, 2010, 10:35 AM	#22
Patrick McLoad Regular Crew Join Date: Mar 2003 Location: Houston, Texas Posts: 52	Thanks Brian, that looked good with no apparent shutter problems. Patrick McLoad

December 28th, 2010, 11:14 AM	#24
Patrick McLoad Regular Crew Join Date: Mar 2003 Location: Houston, Texas Posts: 52	Thanks, will look into them. We have a motion-picture supply / rental outfit here in Houston called Texcam, and they can probably rig up a set for me. I had heard of these but had forgotten. Yes, of course, the chopper crew wouldn't let me off the ground without ALL safety harnesses in place and of the right type. I personally own 4 full-body harnesses and shock absorbing lanyards. I also tie-off the camera. Thank you.