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JimS_99

Easy method to adjust camera?

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I know this topic has been discussed before, I've searched but can't find anything though. I'm definately not a pro or even a semi-pro, just enjoy working on stuff like this around my house.

 

What is a good & easy method of focusing and adjusting camera's without running up & down ladders & stairs? Would a portable DVD player with a video-in input work? I would like some way of looking at a monitor while adjusting the camera.

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Focus inside your house/office with the lights dimmed or even off; with just low lighting. If its a high zoom lens though this can be an issue, then you will need to setup a spot outdoors to do this, and do this in the early evening when there is low light; not pitch dark though.

 

If this is a Varifocal Lens ....

 

If it is a Day Night IR camera, you will need to focus the color in low light, and then the BW mode under Pitch dark with the IRs on. If you dont focus with the IR on then when they do come on, you will normally not have a perfect focus as there is a focus shift (on normal lenses). IR Corrected lenses fix this, but you will only have one of these if the manufacturer specifies this or you install the lens separately. If doing this indoors, you can simply do this at night, and adjust the color mode with the lights on, dimmed or low light, and in the BW mode in pitch dark with the IRs on full.

 

If it is a Day Night camera without IR, simply focus it in low light.

 

If it is a fixed lens or an IR Corrected lens, you should not need to worry about focus shift, and then you can focus it anytime you can get a decent enough image from it. I would still do this under low light, not full sunlight as that can diminish the image quality, as well as your ability to view the image properly if doing this outdoors.

 

Use any portable device or even a TV to simply adjust the view (not the focus) at the location.

 

Don't focus at the location unless it has gone out of focus.

 

Use a high res monitor to focus with, 9" is a perfect size.

Or even something like a 13" TV; anything but an LCD.

 

There really is no "easy" way to focus a camera, but having your own large warehouse with multiple manual lighting conditions, 9" CRT CCTV Monitors, and a Focus Meter; do help.

Otherwise you will get what you get ..

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Rory, great reply!! Thanks!

 

One question, I'm going tp buy a 9" CCTV monitor. Are they pretty much all the same? Or is there one brand that is better than most?

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Ive had a Provideo (OEM) BW 1000TVL now for a few years, so they kind of all last. But the color models are harder to locate in High Res .. so its going to be shopping around. Most i could find generally in 9" Color is around 450TVL, though that still isnt bad seeing as a TV is around 250-300TVL.

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Hello, installers use a 6" TFT monitor for this application. Simply plug the camera directly into this monitor while the camera is mounted in the location. Then adjust the camera till you like the picture. The camera plugs into this monitor unsing a BNC to RCA connector. This saves you the the trip up and down the ladder. Let me know if there is anything else I can do for you. Thanks

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Hi, a 6" TFT monitor is not big nor clear enough to properly focus a camera.

You need a CRT monitor if you want a good focus. Those Portable monitors are great for minor adjustments though.

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That is true. If you want to get the best picture focus, then I suggest a large deticated CCTV monitor. This will give you the best picture for adjusting your camera. The TFT are great, but don't give you the clear, crisp picture you need.

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Rory, In your reply above you say to adjust focus in B/W & Color modes seperately. I"m confused. If you get it in focus in BW mode then it's out of focus in color mode and you adjust it there won't it be back out of focus in BW mode again??? Sounds sorta like chasing your tail.

 

Wouldn't the best time to adjust the focus be right when it's getting dark and almost before the camera switches between modes while it's still in color mode?

 

This forum is a wealth of info!! I'm following your advise so far on focusing & adjusting camera's. I went to BestBuy today and bought a cheap 13" tv to use to focus and adjust my camera's. I think I need an RF Modulator to plug the camera directly into the tv, don't I? What I'm doing is using the GV Spot Camera out and running a 100' piece of coax to the TV that I have hanging off the ladder. LOL It works, but sure isn't very professional LOL I ordered a Tatung 19" 1901 Color Hi-res CCTV monitor today. Should be here in a week or so. The TV thing is just to experiment with until the monitor arrives.

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Thats in regard to IR cameras only, as the BW mode needs to be focused under full IR. Yes you can end up chasing your tail, especially on the cheaper Bullet cameras Best would be the EX82 from Extreme CCTV, as an example.

 

As to the TV, you should be able to just plug it into the RCA input (AV).

Edited by Guest

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That's exactly what I'm trying to focus, a varifocal IR camera.

 

You're right about plugging the TV into the Av. Just tried it and it works!

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Just do those under low light then, but if you focus it in full IR in the dark, it will stay (or should) stay focused in full sunlight. You will have some minor out of focus during low light switches, but since they dont have IR optimized lenses, have to use what we have. That said you could focus it off 5-10% to take for that slight focus shift.

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Thanks for all the info. Just got done adjusting 1 camera following your instructions. Fantastik video!! I thought it was good before, now it's great! 5 more to do now. Again, THANKS!

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Would someone explain these IR cut filters. (Yes, I do know what IR stands for and the difference in wavelengths between IR and visible light)

Why is there a difference between lens with and w/o them? Why this "focus shift?

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i use a 4" tote vision battery-powered monitor most of the time because it's convenient to use, but it is difficult to focus with it.. you can get a good focus if you can pick out something with fine detail (like a sign in a parking lot or a poster on a wall, etc..) but most of the time that isn't really possible. i also use a 10" mintek portable dvd player sometimes, it works a lot better for focusing because of it's higher resolution but it's a pain to use on a ladder..

 

it really is best to pre-focus before installation where possible, using a big crt monitor..

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