delay in switching between day and night

[anorthcote 0]

Hi,

 

I am trialling a camera at my local theatre for use by the stage manager to see the stage from the audience perspective.

 

I am trying a Genie HDED2812IR, all is good except a very long delay (6 seconds) in the night mode activating.

 

When the stage lights go to "black out" I need the camera to switch to IR night mode as quickly as possible, 6 seconds is an entirety in a theatre.

 

I have set any delay settings in the menus to LOW but it is still too long.

 

I have also considered a Samsung SCD-6081R but on reading the manual it looks like the smallest delay that can be set is 5 seconds, still too long!

 

Can anyone suggest a fix, or an alternative hd-sdi dome camera, available in the UK, for around £250?

 

Many thanks.

[SeattleBrian 0]

anorthcote,

 

Welcome to the forum!

 

The camera was designed to handle the transition from daytime to nighttime, which naturally takes some time. So hysteresis is designed in. Damping, so to speak. It makes for a more stable system. Otherwise, the camera could toggle back and forth quickly and repeatedly.

 

You might consider alternative solutions. Could IR illumination be on all the time? A separate IR illuminator could be constantly powered. When stage light got to "black out", the camera would remain in color daytime mode. The image will have a purple-ish tint, due to the IR illumination, but the image contain the things you want to see. Six seconds later, the camera will transition to black & white nighttime mode, and it will turn on its IR LEDs (for additional illumination in this scenario)

 

This may address the real root cause. ie: it's not that you need to switch from color mode (daytime), to b&w mode (nightime) immediately. Instead, you want IR illumination available whenever the lights are switched off.

[anorthcote 0]

Hi, thank you for your reply. What a good idea, it may be a solution for us.

 

In theory, accepting any warranty would be void, could the IR diodes on the camera be re-wired to be always on or would it be easier to get another IR array?

 

I've been spending a lot of time reading up on cameras, I have found another camera - CBP6324DN-HD that shows, in the manual, Day/Night Delay configurable between 0 ~ 255 seconds. Take a look at http://www.videcon.co.uk/uploads/files/CBP6324DN-HD_CVP6324DN-HD_Dome_Manualsplit.pdf

 

What are your thoughts???

 

I have e-mailed the supplier but, not being a trade security distributor, they are being awkward in talking with me!!

[ak357 0]

Hi, thank you for your reply. What a good idea, it may be a solution for us.

 

In theory, accepting any warranty would be void, could the IR diodes on the camera be re-wired to be always on

Cover camera light sensor?

[anorthcote 0]

Wouldn't that enable the night BLACK & WHITE mode at all times?

 

Colour is important unless we are in "black out"

[SeattleBrian 0]

On some cameras, you turn off IR permanently. This capability is demanded by users who aim a camera through a window. When IR turns on, the IR reflected from the window bounces back into the camera, effectively blinding it.

 

But I haven't seen cameras where you can enable the IR to stay on permanently. I don't think there a customer demand for this ability. And this operating mode has drawbacks, in general use. IR illumination will adversely affect the color image. (things will be purple-ish). Going into b&w mode avoids this discoloration.

 

Covering the daylight sensor will turn on IR since the camera will always be in nighttime mode. Unfortunately, in b&w mode.

 

Do a google search for "CCTV Ir Infrared Night Vision Illuminator". I recently boiught a 48 IR LED unit for less than $10.

 

Using the 10 to 12 IR LEDs of the camera for lighting the theatre stage may not provide enough light. I imagine the camera will be further from the stage than the camera's LEDs can adequately light. Therefore, you may need auxiliary illumination anyway!

 

Extra illuminator(s) also allow you to locate them for the best effect. Angle, intensity, eliminate shadows, etc. You state "6 minutes is an eternity in theatre". The corollary may be "poor lighting is is a calamity in theater"

 

Using a camera at a concert or play generally isn't allowed. You could even aim some IR illuminators from the stage area into the audience seating area. It will seriously disrupt anyone taking pictures or movies with their cell phone. And won't affect the human viewing....

 

Have fun!

[anorthcote 0]

very interesting reply. The IR lamp idea would be ideal but, I perhaps didn't explain very well in the first place is, what I am experiencing is when it goes dark the IR diodes illuminate immediately but the camera doesn't switch to night vision until 6 seconds later.

 

This switch over is done with a 'click', is that the IR cut filter moving (I'm a beginner and only just starting to understand the various terminology and technology!)?

 

If that is the case then I could have as much IR illumination possible but the camera would just filter it out until the cut filter is removed. This would still give me a 6 second delay!!

 

Does anyone have any views on my suggested alternative CBP6324DN-HD?

[SeattleBrian 0]

The plot thickens...

Your camera has a moveable IR cut filter. (I had wrongly assumed it was IR correction fillter on the lens, ie: less expensive)

I don't have experience with cameras with mechanical IR cut filters...

 

I looked at both camera spec sheets, I didn't spot either stating a mechanical IR cut filter. The 2nd camera you mention may have the ability to immediately switch to night mode:

DAY & NIGHT: Auto/Day/Night: Delay: 0 to 255 sec

 

I also now realize you're looking at HD-SDI cameras. Is this because you want to take advantage of existing wiring? Siamese wiring: Coax + power

 

If this is a new installation, I'd suggest you look into IP cameras, and use Cat6 cable for the wiring, instead of coax. HD-SDI is a "transition solution". It support new technology HD images, but over old technology coax cable. Existing CCTV installation can upgrade to HD but avoid the expense of rewiring. IP is coming, it has staying power, and if you're doing a new installation, most advise going IP.

 

I see the video is PAL, not NTSC. I gues you're not in the USA (which is NTSC)

[anorthcote 0]

ok, for the IR cut filter I am not 100% convinced I have one. All I know is that when I turn the lights off the IR diodes come on immediately then after about 4 seconds there is a click and the B&W picture comes through. The click is like a relay switching. It may be part of the colour/B&W setting change rather than an IR cut filter moving, I don't know really.

 

Yes, I am looking for HD-SDI, we have an existing system in place and would like to utilise existing cable runs where possible although this isn't the driving force for using this protocol.

 

I looked at IP cameras but all of the cameras I looked at are designed to work with digital recorders and have web based portals for viewing images.

 

What we are after is real time viewing with no recording capabilities (in fact if we had capabilities for recording we would be breaking the performing rights license for most of our productions!). I want a camera and a screen (or two or three screens with splitters).

 

I have the infrastructure purchased and ready to go so I don't want to change that now. I just need to get the camera sorted. And, yes, I'm in the UK so PAL is what I need.

 

I have e-mailed the manufacturer of the last camera I suggested and a re-seller, lets hope I get the right answers.