Help with Graduate Research at DVinfo.net

Mike Jacobson · March 3rd, 2011, 09:37 AM

Hello All

I am a graduate student studying fluid mechanics and was looking for some help. For my research, I need to use some video cameras and, as my area of study has nothing to do with cameras, I figured I would ask for advice from the experts (no harm in a little flattery!) Please forgive me in advance if my camera terminology is off—the more I seem to learn about video cameras the less I feel I know.

What I am attempting has been done before by other researchers but, as with seemingly everything these days, I am trying to do it for cheaper due to budget cuts. Basically, I have a long skinny tank filled with water and certain flow conditions will take place inside the tank. The tank will be backlit by fluorescent lights. I am going to film the front of the tank and determine various quantities based on the amount of light that makes it through the flow.

Typically, people have filmed the tank with CCD cameras. My understanding of this is that CCD cameras are more ‘accurate’, but I also think they might be overkill for my application. I have tested the system using Sony HDR-XR150 camcorders and it has worked relatively well. However, even though I can manually set the exposure, the camera automatically adjusts the gain and aperture. Since I am looking at the amount of light let in, if the camera automatically compensates for darker and brighter scenes, the film is essentially useless.

I was hoping that you could point me to cheap camcorders that allow me to set the exposure, gain, aperture, and any other feature that will affect the amount of light let in to manual. Black and white is fine (preferred actually).

From spending time reading the threads I have seen that most of the camcorders on here are professional, expensive cameras, which I know is in contrast to what I am looking for. But any help you could provide me would be great!—to be honest, I never knew that selecting a camera would be so difficult.

If I haven’t been descriptive enough or if I need to clarify something, please let me know. Thank you in advance!

Garrett Low · March 3rd, 2011, 10:48 AM

Hi Mike,

In addition to doing videography I'm actually a Civil Engineer and a lot of what I do is storm hydrology related.

A Canon makes a line of inexpensive cameras that allow you to lock the exposure so that the gain, aperture, and shutter speed are fixed. They are up to the third generation of the and the current model is a Canon HV40, If you can find a used HV20 or HV30 they should be no more than $300 or $400.

Cheers
Garrett

March 3rd, 2011, 09:37 AM	#1
Mike Jacobson Tourist Join Date: Feb 2011 Location: Clemson, SC Posts: 1	Help with Graduate Research Hello All I am a graduate student studying fluid mechanics and was looking for some help. For my research, I need to use some video cameras and, as my area of study has nothing to do with cameras, I figured I would ask for advice from the experts (no harm in a little flattery!) Please forgive me in advance if my camera terminology is off—the more I seem to learn about video cameras the less I feel I know. What I am attempting has been done before by other researchers but, as with seemingly everything these days, I am trying to do it for cheaper due to budget cuts. Basically, I have a long skinny tank filled with water and certain flow conditions will take place inside the tank. The tank will be backlit by fluorescent lights. I am going to film the front of the tank and determine various quantities based on the amount of light that makes it through the flow. Typically, people have filmed the tank with CCD cameras. My understanding of this is that CCD cameras are more ‘accurate’, but I also think they might be overkill for my application. I have tested the system using Sony HDR-XR150 camcorders and it has worked relatively well. However, even though I can manually set the exposure, the camera automatically adjusts the gain and aperture. Since I am looking at the amount of light let in, if the camera automatically compensates for darker and brighter scenes, the film is essentially useless. I was hoping that you could point me to cheap camcorders that allow me to set the exposure, gain, aperture, and any other feature that will affect the amount of light let in to manual. Black and white is fine (preferred actually). From spending time reading the threads I have seen that most of the camcorders on here are professional, expensive cameras, which I know is in contrast to what I am looking for. But any help you could provide me would be great!—to be honest, I never knew that selecting a camera would be so difficult. If I haven’t been descriptive enough or if I need to clarify something, please let me know. Thank you in advance!

March 3rd, 2011, 10:48 AM	#2
Garrett Low Trustee Join Date: Jul 2007 Location: Novato, CA Posts: 1,774	Re: Help with Graduate Research Hi Mike, In addition to doing videography I'm actually a Civil Engineer and a lot of what I do is storm hydrology related. A Canon makes a line of inexpensive cameras that allow you to lock the exposure so that the gain, aperture, and shutter speed are fixed. They are up to the third generation of the and the current model is a Canon HV40, If you can find a used HV20 or HV30 they should be no more than $300 or $400. Cheers Garrett __________________ Garrett Low www.GLowMediaProductions.com