No control over lighting at DVinfo.net

Judy Tate · April 9th, 2004, 07:36 AM

We are using a Canon Optura Xi for research in the ICU. Our objective is to document patient communication, facial expressions, gestures, etc. And (most importantly) we are nurses not videographers.

The rooms are lit with overhead fluorescents which may or may not be on. And there is a large window behind the patient and shades may or may not be drawn. In order not to interfere with the natural setting (a violation of the protocol) we are unable to control the lighting during filming.

The quality of our video has ranged from great to horrid. We have had the patient's face washed out and we have also had the images be completely shadowed. The image on the LCD during filming has been acceptable, however they change during transfer to the computer.

OK, keep in mind our skill level and the idea that we have budget constraints. Any ideas?

Allen Brodsky · April 9th, 2004, 08:13 AM

Position yourself, when possible, so that the window is behind you, rather than shooting with the camera pointed toward the window. If you shoot facing the window when the blinds are open on a sunny day, your camera will adjust for the brightness from the window, resulting in faces being too dark.
Since you can't control the lighting, you will have to move around the room to find the best places for filming. As you get more experience with this, you will no doubt improve greatly. Try to practice in an empty room, with a couple of you acting as the patient and doctor, etc., and just take shots from different places in the room. Make notes about where the shots were made, then see where you got the best shots.
Since the shots seem to change when you view them on your PC, check the brightness/contrast of your monitor and your editing software. Maybe these aren't adjusted properly for video. How does your video look when output to tape and viewed on your TV?
Hope this helps. Sounds like a good project!

Judy Tate · April 9th, 2004, 08:52 AM

Thanks for the ideas. So far we have not transferred to tape, nor have we viewed on a TV. We intend to transfer the video to DVD for storage, but to analyze the video on the computer. Again, our expertise with the editing software is another likely gap that we'll need to ramp up in order to achieve optimal results.

It would be great if we could film with the window behind us, but then we'd be filming from the back of the patient's head. Not too much data there! We will continue to pilot different positions within the room and document. It might be better, I suppose if we shot from an angle at the patient's bedside rather than a straight on shot from the hallway.

Again, thanks.

Rob Wilson · April 9th, 2004, 08:54 AM

Judy,

Since you can't control the light, you have to control the exposure. I'm not familiar with the cam you're using but hopefully it has some manual controls.

Try zooming in on the patients face (primary subject right?). By doing this, you have eliminated the backlight from the automatic exposure system. Lock your exposure controls (shutter/apature). Now you're free to zoom out/reframe while maintaining the correct exposure on the patient. I'm guessing the others in the room may also be included and since the overall light quality shouldn't change much, you'll get good exposures of them also. The only thing you'll loose is what's on the other side of the window, it'll be way overexposed.

April 9th, 2004, 07:36 AM	#1
Judy Tate Tourist Join Date: Apr 2004 Location: Pittsburgh, PA Posts: 2	No control over lighting We are using a Canon Optura Xi for research in the ICU. Our objective is to document patient communication, facial expressions, gestures, etc. And (most importantly) we are nurses not videographers. The rooms are lit with overhead fluorescents which may or may not be on. And there is a large window behind the patient and shades may or may not be drawn. In order not to interfere with the natural setting (a violation of the protocol) we are unable to control the lighting during filming. The quality of our video has ranged from great to horrid. We have had the patient's face washed out and we have also had the images be completely shadowed. The image on the LCD during filming has been acceptable, however they change during transfer to the computer. OK, keep in mind our skill level and the idea that we have budget constraints. Any ideas? __________________ JT

April 9th, 2004, 08:52 AM	#3
Judy Tate Tourist Join Date: Apr 2004 Location: Pittsburgh, PA Posts: 2	Thanks Thanks for the ideas. So far we have not transferred to tape, nor have we viewed on a TV. We intend to transfer the video to DVD for storage, but to analyze the video on the computer. Again, our expertise with the editing software is another likely gap that we'll need to ramp up in order to achieve optimal results. It would be great if we could film with the window behind us, but then we'd be filming from the back of the patient's head. Not too much data there! We will continue to pilot different positions within the room and document. It might be better, I suppose if we shot from an angle at the patient's bedside rather than a straight on shot from the hallway. Again, thanks. __________________ JT

April 9th, 2004, 08:13 AM	#2
Allen Brodsky Regular Crew Join Date: Jun 2003 Location: Eatontown, NJ Posts: 118	Position yourself, when possible, so that the window is behind you, rather than shooting with the camera pointed toward the window. If you shoot facing the window when the blinds are open on a sunny day, your camera will adjust for the brightness from the window, resulting in faces being too dark. Since you can't control the lighting, you will have to move around the room to find the best places for filming. As you get more experience with this, you will no doubt improve greatly. Try to practice in an empty room, with a couple of you acting as the patient and doctor, etc., and just take shots from different places in the room. Make notes about where the shots were made, then see where you got the best shots. Since the shots seem to change when you view them on your PC, check the brightness/contrast of your monitor and your editing software. Maybe these aren't adjusted properly for video. How does your video look when output to tape and viewed on your TV? Hope this helps. Sounds like a good project!

April 9th, 2004, 08:54 AM	#4
Rob Wilson Major Player Join Date: Dec 2002 Location: Flagstaff, AZ Posts: 473	Judy, Since you can't control the light, you have to control the exposure. I'm not familiar with the cam you're using but hopefully it has some manual controls. Try zooming in on the patients face (primary subject right?). By doing this, you have eliminated the backlight from the automatic exposure system. Lock your exposure controls (shutter/apature). Now you're free to zoom out/reframe while maintaining the correct exposure on the patient. I'm guessing the others in the room may also be included and since the overall light quality shouldn't change much, you'll get good exposures of them also. The only thing you'll loose is what's on the other side of the window, it'll be way overexposed.