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-   -   Helmet Camera user experience (https://www.dvinfo.net/forum/open-dv-discussion/31705-helmet-camera-user-experience.html)

Mike Rehmus September 10th, 2004 01:18 PM

Helmet Camera user experience
 
I just purchased a HelmetCam and am having a few problems with it.

1. When the camera is inserted into the aluminum safety mount, the picture is vignetted even though the camera is touching the plastic cover of the safety mount.

2. As the police office rides around a large blacktop parking lot, the color balance of the camera flops around.

Similar experiences? Solutions?

Aaron Rosen September 10th, 2004 03:35 PM

What kind did you get?

I attached one to my side view mirror. It worked ok but it was to dark to see if the color balance shifted and I think I did cut off a bit at the ends.



What are you using to record?

Mike Rehmus September 10th, 2004 04:36 PM

It is actually called HelmetCam. I feed it into my Sony PC-110 that I hang on the officer's waist.

I just shipped it off to Helmetcam as they say the color balance shift and vignetting are unusual. They promise to have it back before the 18th when it is scheduled to be used in the Harley-Davidson West Coast Police Motorcycle Competition.

Aaron Rosen September 10th, 2004 05:05 PM

Sounds great.

You got if from helmetcam.com? Thats where I borrowed my buddies from.

The rez. is pretty good in the right light.

Ide love to see some footage when you get it back.

Mike Rehmus September 20th, 2004 07:30 PM

Ok, 3 helmet cameras later.

I tried 2 copies of the HelmetCam product and returned them because of color shifts when the camera is rapidly panned.

Ordered a Laird Helmet Camera setup. Quite a bit nicer but still the same problems. Still, this one in a bit nicer in its integration with a small lead-acid battery with charger rather than a 8-hole AA battery holder from HelmetCam and a large rubber band to hold the batteries in place. Nicer case too.

However, their microphone is almost useless as it has a miniplug output and only microphone level available. Most camcorders I know of deactivate the microphone input when in VTR mode.

So I've ordered the Laird miniature microphone preamp and will use my Shure SM-11 which is a large, clunky dynamic lavaliered that can take a lot of overpressure and general abuse.

I'm sticking with the Laird because it does work OK except for the color shift but then most applications won't be moving the camera rapidly like a Police Officer looking for the next pylon to drive around on his Harley.

But I do want to take it on a rollercoaster! Good thing Six Flags has a location here in town.

Bottom line? It costs more than $500 to get a decent helmet camera.

Rick Bravo September 20th, 2004 07:49 PM

G-Forces!!!
 
The helmet cam will fair well on a coaster, but...the G-Forces will play havoc with the tape transport.

I faired much better in the back of an F-16C than the Hi-8 cam that went up.

Which Laird did you get? Let me know how it performed.

RB

Dan Euritt September 20th, 2004 09:18 PM

it doesn't seem possible that 3 different cameras can all have a color shift problem when put into motion... they are solid-state devices, maybe try looking elsewhere to solve that problem... wiring, the pc-110 connector, manually balance the color if possible, etc.

rick is right about the tape transport, it won't hold up under serious useage.

here is a clip of what i shot with my on-board camera: http://www.oceanstreetvideo.com/vide...ncarcamera.zip

you'll have to save it to your local drive, and unzip before viewing... and yeah, that rig cost me more than $500!!

Aaron Rosen September 20th, 2004 09:24 PM

Whats the link to the Laird website?

Mike Rehmus September 20th, 2004 09:59 PM

I got the high-res version.

It did ok except for the color changes caused by moving the camera too fast. Microphone not worth a hoot. Have ordered their $90 very small microphone preamp and will use it with a dynamic microphone to better handle loud noises.

If you get one, either order extra velcro or find a separate supply (assuming you want to move the camera around).

I think it would be very good for using outdoors in inclement weather where you'd like to keep the recorder under wraps.

I put everything in a rain-proof and padded fanny pack. I'd probably cut holes in the bottom so I could keep the zippers fully closed in bad weather. Hate to cut THAT fanny pack but I could, I suppose.

I also got the remote Lanc control unit. Push the button once to power up the camera, push again to record, push to stop, hold button down to turn off the camera. LED is red when recording, green while in pause. Also indicates faults with a flashing red LED. It is a double-color LED and it is small. The entire control is kind of the shape of an old-fashioned bell-push without the mounting ears. Maybe 75% of the bell-push size. It could be glued down or whatever.

For the motorcycle comp, we just drapped the cord between the officer's belt and his weapon. He'd just look down and trigger the camera and off he'd go.

We first placed it on the last rider in the Oakland Police Motorcycle Drill Team. Nice effect, especially when they started hauling tail down the street. Then we put it on one of our officers who was in the competition. Incredibly smooth looking but he was really hauling. I'd have put it on the officer who rode his bike 2 blocks standing on the saddle and holding a salute had I known they were going to do that. A large American flag streaming from the rear fender.

Unfortunately, the microphone included in the Laird, even though it worked for me on Friday, did not work on Saturday. Laird said it should have never worked. So I sent the camera through on a couple of rides just using its on-board microphone. All sealed up in the fanny pack, it recorded a nice Harley-Davidson sound.

As a side note, the Napa motorcycle squad was represented by just a single officer. To give him a partner for the doubles competition, they asked the Harley rep to ride with him on a loaner motor. The officers rode nose to tail on two motors. By the end of the course, most of the guys in the rear were way back. The Harley rep stuck like glue and they came in 3rd in a very fast field. Turns out the guy is a retired Miami Motor Cop! His name is Bob Foreman and can he ride. Probably could take first or second in the competition if they allow him to run.

Mike Rehmus September 20th, 2004 10:30 PM

<<<-- Originally posted by Dan Euritt : it doesn't seem possible that 3 different cameras can all have a color shift problem when put into motion... they are solid-state devices, maybe try looking elsewhere to solve that problem... wiring, the pc-110 connector, manually balance the color if possible, etc.
-->>>

The problem is inherent in CCD techonolgy according to Laird tech support. All CCDs exhibit this problem but most of use view video through a compensation system that these cheap Sony cameras don't have. There are no external means of controlling the camera. I also tried it with a PD150 with the same results.

Conclusion is that it is possible and, in fact, certain.

Dan Euritt September 21st, 2004 03:09 PM

do you see any color shifting in the clip that i posted? maybe i just didn't notice it?

i've used at least 3 different on-board cameras over the years, and i don't recall ever having a color shift problem.

everything else has gone wrong, tho! lol

those cops on bikes sound like a blast to videotape.

Mike Rehmus September 21st, 2004 05:05 PM

You missed my statement about why the color shift occurs, Dan.

In the use you put it to, the shift would never occur.

But when you place it on a helmet and the rider then runs an obstacle course at speed, their rapid head movements cause the problem. Held more or less steady, without the equivalent of a rapid pan, the issue will never arise.

When I mounted the camera on the helmet of an Oakland Police Officer Drill-Team member, their motion is far less violent and the problem did not arise.

Now Harley Davidson wants to build a tandem saddle for me. Facing backwards, I can tape another person following us through the cones. I guess I need a helmet mounted viewfinder so I can see what the camera is shooting. I learned not to ride with the viewfinder up to my eye when I shot another airplane from the back seat of a biplane. The air buffeting the camera gave me a black eye over the course of several hours.

Dan, do you have the camera strapped to a roll bar? Or do you have some sort of flexible mount to absorb shock? The police want me to mount the camera on the front fork of the motorcycle. I'm afraid the Harley shake will just beat the camera to pieces or at the least, let the image shake a lot.

Dan Euritt September 22nd, 2004 10:32 AM

i just can't get my brain to wrap around the concept that it can't be fixed with manual color balancing... but i'm trying, lol!

i have heard that those virtual reality glasses will work for framing a video shot.

all the in-car camera stuff that i have shot was done with the i/o port roll bar mount bolted to the roll cage of the car... the bad vibration problem arises when the roll cage reaches a real serious resonant frequency that's brought on by certain engine rpm's on the starting line... i had to loctite the lens to the lipstick camera to keep it from coming unscrewed, and then the wiring connector vibrated right off of the back of the camera, despite it's own locking arrangement, so i had to rig up a bunch of zip-ties for that.

i found that hard-mounting the camera was the only way to go, but the i/o port device does have a thick urethane gasket in it... any kind of flexible mount other than that will seriously increase the camera shake.

putting the camera on the front fork of a motorcycle would be a great shot, if you have a wide-angle lense... but it's gonna be a challenge!

Mike Rehmus September 22nd, 2004 11:54 AM

<<<-- Originally posted by Dan Euritt : i just can't get my brain to wrap around the concept that it can't be fixed with manual color balancing... but i'm trying, lol! -->>>

Probably can but the color correction would have to be keyframable so it could be controlled as the color change isn't (I think) a snap change from one frame to another. But it could be, I've not analyzed the footage for that but I will now!)


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