Test Monitors

[G-MEN 0]

What kind of test monitors do you use? I use a tote vision and I'm not real pleased with it. Thinking about getting a ganz PSM-02.

[VST_Man 1]

get the CM-2........takes the human factor out and provides you with several video checks to help in troubleshooting CCTV.

 

use the test monitor for pic view only and the CM-2 to set focus.

[cctv_down_under 0]

I have to admit I use the Ganz, it is a little small but the loop through is great and the built in disty amp really helps

[libertysurveillance 0]

we use the tatung monitor here, nice heavy duty, though i wish there where better cases for these things..

 

its basically the same thing as the ganz, just looks a bit different.

[CollinR 0]

I just use a cheapo 12v LCD.

[griffonsystems 0]

CM-2?

[rory 0]

9" CCTV BW 1000TVL monitor - need at least a 9" Monitor to focus a camera properly.

[griffonsystems 0]

how do you hang a 9" monitor around your neck on a ladder?

 

rory do you have a step by step approach to focusing a camera that you could share,, i use my small handheld and make the 2 adjustments with the lens and then im off to the next camera

[rory 0]

i focus in the evening when its dark, outside on a plastic table, do each camera one at a time, focused on my jeep, then when they are all setup, take them to the location ... but then thats just me ..

 

But yes I also have carried the 9" monitor up the ladder many times before ..

Once you dont mount the cameras at a crazy height (which you shouldnt) then its okay.

[CSG 0]

My tech just busted my little Supercircuits handheld that runs off AAA batteries that he was borrowing. I had a feeling when he gave it back to me something was rotten.

 

oh well they only cost $99

[libertysurveillance 0]

9" CCTV BW 1000TVL monitor - need at least a 9" Monitor to focus a camera properly.

 

I use my tatung 2.5" to aim.. use a walkie talkie's to focus

[VJD 0]

Everfocus EN220.

 

Nice size screen and the straps works well but a little hard to see in sunlight.

 

I'm thinking about the CM-2; depending on the cost.

[vitHoward 0]

Don't forger that when focusing a lens you MUST OPEN THE IRIS first. Use a #5 welders lens to force a auto-iris open during the day. Otherwise you're likely to have a great picture during the day but the nighttime shot will be fuzzy (out of focus).

 

Howard

www.videoguardit.com

[cctv_down_under 0]

Not if you use some of the newer cameras like the LTC range from Bosch, they do this for you and still give you the same image to focus with, they simulate the backfocus so that you never have worry about it, i threw my ND filter out the day this happened

[vitHoward 0]

That's what I love about this business. I learn something new everyday!

 

Howard

www.videoguardit.com/cctv_essentials.html

[Cooperman 0]

This may be a slight drift off the original topic, but I'm sure you'll forgive me ....

 

The improvements in technology may indeed make it easier for an individual to achieve a sharp focus, but some basic background knowledge is still very useful.

 

Achieving the correct 'back focus' setting, is simply a mechanical mechanism that enables you to correctly exploit the full focus range of whatever lens is fitted (assuming of course it's not fixed focus ).

 

The point about focussing the lens itself, exploiting the available depth of field, and achieving an optimum setting for the application, doesn't necessarily mean that the focus has to be set on the precise location of a target.

 

Now before you think I've totally flipped, I'll try and explain in simple terms.

 

If for example you were setting up a camera indoors under controlled lighting, perhaps looking along a corridor 50 feet long, the temptation might be to set the focus at around 20 feet; the assumption being that the depth of field will take care of much of the rest.

 

In practice, it would probably have been better to set the primary focus at perhaps around 30 feet; the simple reason is that whilst depth of field increases in size as the distance to target increases, it is also a basic principle of optics, that the depth of field normally extends for about 30% in front of the point of focus, and roughly 70% behind (and not 50:50 as is often mistakenly quoted).

 

So within reason, the further away you focus, the larger the depth of field (same basic concept for all lenses whether wide angle or telephoto).

 

This is a standard principle much known to professional photographers, who are often told when taking pictures of people, to focus on the eyes. That way, the nose (a short distance in front) and the ears (much further behind) will hopefully all be sharp in the eventual picture.

 

It's also a very good reason why in some indoor situations, in can be extremely beneficial to use a highly sensitive camera (allowing a smaller lens aperture, with a resultant greater depth of field).

[vitHoward 0]

Cooperman,

It's so nice to read a post from someone who knows what they are talking about. Cheers!

Howard

[Cooperman 0]

vitHoward,

 

You're far too kind, and that creates a bit of problem for me;

 

I always swore i'd retire when people start to think I know what I'm talking about ....

 

.... and there's still so much working life in the old dog yet

[baywatch 1]

I have been using Archos 420 dvr walkmen for various covert tasks & have sold more than 20 since Christmas.

 

I now use it as a set up monitor & it has the advantage that you can record the view to show the customer from different positions. We use a little rechargeable battery to power the camera & easily show the different views from different lenses etc.

[kg6mti 0]

I picked up a 7" flat panel DVD monitor the other day. It is designed to be installed in a car so it already runs off 12V DC. The screen resolution is great. It is very light and easy to carry. It came with its own case, cables, and AC/DC adapters. It has input for RCA audio and video and S-Video input.

 

All I did was make a patch cable with a piece of cut off coax RG-59 and a couple of ends. Then I bought a RCA - BNC connector to convert the RCA inputs on the monitor to male BNC. I have also created a 12V DC Y adapter so I can use power from the camera if I want to. This way all I have to carry up to the camera is the monitor.

 

So far it works perfect and the total cost was only around $90 US. When I am not using the monitor to adjust the camera's I can use it in my car connected to a mobile DVD player to watch movies.

[AVCONSULTING 0]

This was at the ISC show, very nice little package.

 

http://www.vitekcctv.com/ProductDetails.asp?ProductID=188