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TV to set up cameras

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I've generally used portable DVD players that have A/V inputs... my favorite was a 10" one I had that had a flip-around, fold-flat screen and a case with straps that would let me clip it to the top of a ladder or the railing of a lift. Alas, it died a quiet death...

 

My coworker recently got one of these and it works great, so I got one too - can't beat the price!

 

He actually used to have an Archos media player - little thing with a wrist strap that made it very handy for using on a lift or ladder, PLUS it had an 800x480 resolution screen, which made focusing a lot easier (most portable players are only 400x240 resolution).

 

Rory should be chiming in here any second to tell you the only way to do it right is to lug a 14" or larger CRT up the ladder with you...

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its funny you should recommend the 7 inch Haier, i was looking also at this model:

 

http://www.amazon.com/Haier-HLT71-7-Inch-Handheld-LCD/dp/B001E78UQY/ref=wl_it_dp_o?ie=UTF8&coliid=I3I6FANVA08TMK&colid=31QL4BSN37OB2

 

plus you can buy this hood, should help see better in the sun:

 

http://www.amazon.com/ProAm%C2%AE-Video-Monitor-Hood-Sunshade/dp/B003KV3R1K/ref=wl_it_dp_o?ie=UTF8&coliid=I2GTXMJI3ZSI5B&colid=31QL4BSN37OB2

 

i figured i could duct tape a coat hanger type thing around the TV and hang it off the rain gutter...

 

at least i am on the same page, i was worried that someone would recommend some crazy 800.00 unit...

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There are some really nice units out there, that can provide 12V power for cameras, have high-res 4:3 screens (most DVD/consumer units these days are 16:9 widescreens, meaning camera pictures are stretched), PTZ control outputs, signal generators, cable testers, and even "focus meters" (watches image sharpness and displays a "meter" showing when focus is sharpest). But yeah, those tend to be really spendy...

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I use the Haier 7" unit for my own personal jobs. It works well and is cheap. At work I use a high end unit that can do almost anything but its about 15x-20x the cost of the 7" Haier.

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A 9" High Res CCTV CRT Monitor (or larger) is the best, though like the rest I also use a portable DVD Player. LCD is generally not as good quality for focusing, just doesnt show all the pixels, so its a gamble.

In fact a 13" CRT TV is better for focusing than those LCDs, but carrying it up a ladder is a PITA, and finding one these days can be difficult (at least down here).

 

I focused alot of cameras at different places over the past week and in most cases I used the 9" CRT as that got me the best focus (on ladders as well without issue), had the portable DVD hooked up as well but the 2 images do not compare at all (use the DVD for color settings/OSD setup and adjustment). I focused some today with the DVD but have to go back and fine tune a couple with the CRT. Either way the portable DVD player is handy and cheap and is a must (or something similar at least 7"), though fine tuning/testing requires something better - my truck doesnt leave home now without BOTH of them.

 

BTW I Also have a focus meter but rarely use it, reason is if there is motion in the video it will never focus, or take forever, also I find I get a better focus by eye.

 

For bright sunlight I carry a black tee shirt [1] and throw that over my head and the monitor (also use it to just generally block some sun from my head and neck in addition to a cap) but only with the DVD as with the CRT its too dangerous (hence Id never try focus with the CRT in the bright sunlight), but its not best to focus it in that bright sunlight anyway, wait for low light, early evening for example or a cloudy day. Some use filters to open the iris though I never had any luck with them.

 

If I havent explained myself good enough, to make it simpler ... for my own cameras I focus and adjust with the portable DVD, if I dont like the image quality then I break out the CRT in the evening. Clients are different and if I have the cameras prior to installation then in many cases I would prefocus in a controlled lighting environment for best possible video [2], otherwise you do the best you can out in the field.

 

[1] It does not necessarily have to be a black tee shirt, it can be a black towel, a blue tee shirt, or whatever.

[2] if zoom will be set to widest FOV, (99% of my jobs) OR if decided zoom using a view finder

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its funny you should recommend the 7 inch Haier, i was looking also at this model:

 

http://www.amazon.com/Haier-HLT71-7-Inch-Handheld-LCD/dp/B001E78UQY/ref=wl_it_dp_o?ie=UTF8&coliid=I3I6FANVA08TMK&colid=31QL4BSN37OB2

 

plus you can buy this hood, should help see better in the sun:

 

http://www.amazon.com/ProAm%C2%AE-Video-Monitor-Hood-Sunshade/dp/B003KV3R1K/ref=wl_it_dp_o?ie=UTF8&coliid=I2GTXMJI3ZSI5B&colid=31QL4BSN37OB2

 

i figured i could duct tape a coat hanger type thing around the TV and hang it off the rain gutter...

 

at least i am on the same page, i was worried that someone would recommend some crazy 800.00 unit...

 

That is the one that I was going to recommend. rechargeable battery built in and for $50.00 can't go wrong.

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... if I have the cameras prior to installation then in many cases I would prefocus in a controlled lighting environment...

Which works great IF you can pre-gauge your FOV, know the exact distance a camera will be from its area of interest, and have some test targets set up at the appropriate range(s).

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... if I have the cameras prior to installation then in many cases I would prefocus in a controlled lighting environment...

Which works great IF you can pre-gauge your FOV, know the exact distance a camera will be from its area of interest, and have some test targets set up at the appropriate range(s).

Should I Include a Disclaimer that its only useful if you are setting the camera to its widest FOV? (99% of applications) I didnt know I had to go into such detail, perhaps I will stop what I am doing next time and spend an extra hour writing an entire article.

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what i plan on doing, once i get the Haier TV is to get some poster board, and drawing some shapes and images on it, kinda like an eye chart at the doctors office, and then placing the board in the location that i want most defined and focused,,,,then focusing the cameras for the best image from those locations....

 

also what i like about the Haier is the rechargeable battery, i don't have to have a trailing power extension connected to the TV...

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all portable DVDs have rechargeable batteries .. i have whats left of a coby with a swivel screen.

once i remember to turn it off after each use I get a few days out of it now.

But like i said, dont expect to be able to make the perfect focus with them all the time.

 

For objects to focus on, just pick something with contrast, eg, front grill of a car, fence, etc.

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For bright sunlight I carry a black tee shirt [1] and throw that over my head and the monitor (also use it to just generally block some sun from my head and neck in addition to a cap) but only with the DVD as with the CRT its too dangerous (hence Id never try focus with the CRT in the bright sunlight), but its not best to focus it in that bright sunlight anyway, wait for low light, early evening for example or a cloudy day. Some use filters to open the iris though I never had any luck with them.

[2] if zoom will be set to widest FOV, (99% of my jobs) OR if decided zoom using a view finder

 

I can see the medics scratching their heads when they're called to a fall victim "so what do you think this guy was doing with the TV in a t-shirt wrapped around his head at the top of that ladder anyways?"

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My wife wanted a little portable 7" LCD TV a couple of years ago when the TV signals changed to all digital. We live in a hurricane prone area and she wanted it for the next time we get hit and the power goes out. It sat around collecting dust until I decided to use it one day to focus a couple of cameras. It's now part of my toolkit and works great

 

Something else I've done when I've forgotten to charge the portable TV is to connect the DVR to a wireless router and use my laptop to focus the cameras. It can be a little frustrating because of the small lag (and balancing the laptop isn't fun), but it's worked in a pinch. Sometimes I'll have someone on the ground with the laptop and I'll yell out "how's it look" and am met with replies like "back a little, got it, nope, back, no - the other way, ok, just little more - oops, too far"

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Ha! Done that one! Thus far I have cheap cams that auto focus so the only thing I need to do is adjust the angle/viewing area. I learned very quickly to bring my cell phone up with me so I can call the honey while she sits and views the placement remotely on the laptop- all from the comfort of our couch. Put her on speaker phone and whala- LOTS of up and down the ladder saved. Especially since I got better at communicating what I want to see, and her communicating what she's seeing. I rarley have to go back up to adjust after our dance.

 

 

Dan

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Thus far I have cheap cams that auto focus

they dont autofocus, that would be an expensive camera that does that like with a zoom lens

They just come focused to a particular zoom. Also they dont always come focused properly, many cases I refocus fixed lens cameras also.

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Ah yes- thanks for that clarification Rory. I wish I could do that. I just assumed it came down to my cheap cams having only 400tvl, but maybe it's more so they're actually focused for a set distance and I'm not at it with my placement?

 

Dan

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i found that focusing really cheap cameras rarely makes a difference .. sometimes its down to other factors like really cheap lenses and chips

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