Shutter speed creating image problem at DVinfo.net

Joe Seidel · April 19th, 2011, 06:44 AM

I've had my NXCAM for over a year now with no problems since the firmware upgrade. But I came across an issue today and wonder if anyone else has experienced it.

I've always shot in manual with the shutter speed set to 60 and adjusted the iris accordingly, however I wanted to shoot an interview with a shallower depth of field and left the iris wide open. I then increased the shutter speed to 350. After doing this I noticed i was getting a slowly rolling dark area up the screen. I thought it was an LCD screen issue but it also appears in the recorded video.

Is this normal and I'm doing something wrong? Or is this an issue with my camera? I uploaded a quick YouTube video of me messing around with the camera. You can see it more in the lighter area on the left side of the screen.

YouTube - Clip #4 - 2011-04-19.mov

Yannick Hausler · April 19th, 2011, 07:54 AM

WOW. I have never seen such a thing before. I change the shutter a lot on my NX5P but this has never occurred to me.
Have you tried turning on/off the anti-flicker filter in the menu?
What lights are you using to illuminate the room/scene and yourself?

Joe Seidel · April 19th, 2011, 08:03 AM

Yes I just tried the flicker filter on and off. There's no difference.

I have a Comer LBPS-1800 on the camera. Other than that it's just natural lighting. The problem also exists with the light off.

Joe Seidel · April 19th, 2011, 08:23 AM

Since you mentioned about lighting... I went back to the location and believe I may have found the problem. There is a bank of fluorescents in the ceiling that were on during the taping. I tried turning them off and this video "glitch" went away. Big relief. Thanks for spawning that thought. I just never thought of those flourescents having that great of an effect.

I'm going to continue to experiment a bit, but all indications are good tha this was the issue.

Tom Hardwick · April 19th, 2011, 09:41 AM

Yup - that's it Joe - strobing with the mains frequency.

April 19th, 2011, 06:44 AM	#1
Joe Seidel New Boot Join Date: Mar 2010 Location: Pittsburgh, PA Posts: 17	Shutter speed creating image problem I've had my NXCAM for over a year now with no problems since the firmware upgrade. But I came across an issue today and wonder if anyone else has experienced it. I've always shot in manual with the shutter speed set to 60 and adjusted the iris accordingly, however I wanted to shoot an interview with a shallower depth of field and left the iris wide open. I then increased the shutter speed to 350. After doing this I noticed i was getting a slowly rolling dark area up the screen. I thought it was an LCD screen issue but it also appears in the recorded video. Is this normal and I'm doing something wrong? Or is this an issue with my camera? I uploaded a quick YouTube video of me messing around with the camera. You can see it more in the lighter area on the left side of the screen. YouTube - Clip #4 - 2011-04-19.mov

April 19th, 2011, 07:54 AM	#2
Yannick Hausler New Boot Join Date: Sep 2010 Location: UK Posts: 18	Re: Shutter speed creating image problem WOW. I have never seen such a thing before. I change the shutter a lot on my NX5P but this has never occurred to me. Have you tried turning on/off the anti-flicker filter in the menu? What lights are you using to illuminate the room/scene and yourself?

April 19th, 2011, 08:03 AM	#3
Joe Seidel New Boot Join Date: Mar 2010 Location: Pittsburgh, PA Posts: 17	Re: Shutter speed creating image problem Yes I just tried the flicker filter on and off. There's no difference. I have a Comer LBPS-1800 on the camera. Other than that it's just natural lighting. The problem also exists with the light off.

April 19th, 2011, 09:41 AM	#5
Tom Hardwick Inner Circle Join Date: Mar 2003 Location: Billericay, England UK Posts: 4,711	Re: Shutter speed creating image problem Yup - that's it Joe - strobing with the mains frequency.

April 19th, 2011, 08:23 AM	#4
Joe Seidel New Boot Join Date: Mar 2010 Location: Pittsburgh, PA Posts: 17	Re: Shutter speed creating image problem Since you mentioned about lighting... I went back to the location and believe I may have found the problem. There is a bank of fluorescents in the ceiling that were on during the taping. I tried turning them off and this video "glitch" went away. Big relief. Thanks for spawning that thought. I just never thought of those flourescents having that great of an effect. I'm going to continue to experiment a bit, but all indications are good tha this was the issue.