| Author |
Message |
Richard Tubb
Guest
|
 Posted:
Thu Mar 10, 2005 4:58 pm Post subject:
CCTV Interface |
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Hi,
Have had a good google on this subject but can't find any help - so am
hoping somebody in this newsgroup can. I've lurked here for a while and
can't find a more suitable newsgroup that covers CCTV but apologies if this
is slightly off-topic.
I'm using a Geovision GV-250 PC based CCTV recording system. It has two
cameras, one aimed at my drive and another at my front garden. Both cameras
work fine during daylight but after dusk start displaying what I can only
describe as "rolling white lines" that interfere with the display and the
motion detection recording. The display itself stays still, but hazy white
lines roll down across it. This is a larger problem on the drive than it is
on the front garden camera where the white lines are less bothersome.
I've had it suggested that this is "power" interference. Would anybody agree
with this?
What I find odd is that I have another separate camera (on a different
system) pointed by my front door, nearby the drive, and this also exhibits
the same "white line" problem and it's cabling goes no-where near the drive
camera.
One final piece of info - I live by a electricity sub-station - it lies less
than 100m at the end of my garden. If "power interference" is an issue -
could it be generated by the sub-station? If so, how do I protect against
this?
Any suggestions on what I might do to alleviate this problem gratefully
received.
Regards,
Richard Tubb.
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Paul Worsley
Guest
|
| Posted:
Thu Mar 10, 2005 8:20 pm Post subject:
Re: CCTV Interface |
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"Richard Tubb" <richard@netlinktrading.co.uk> wrote in message
news:iLVXd.34671$y25.3761@fe3.news.blueyonder.co.uk...
| Quote: | Hi,
Have had a good google on this subject but can't find any help - so am
hoping somebody in this newsgroup can. I've lurked here for a while and
can't find a more suitable newsgroup that covers CCTV but apologies if
this is slightly off-topic.
I'm using a Geovision GV-250 PC based CCTV recording system. It has two
cameras, one aimed at my drive and another at my front garden. Both
cameras work fine during daylight but after dusk start displaying what I
can only describe as "rolling white lines" that interfere with the display
and the motion detection recording. The display itself stays still, but
hazy white lines roll down across it. This is a larger problem on the
drive than it is on the front garden camera where the white lines are less
bothersome.
I've had it suggested that this is "power" interference. Would anybody
agree with this?
What I find odd is that I have another separate camera (on a different
system) pointed by my front door, nearby the drive, and this also exhibits
the same "white line" problem and it's cabling goes no-where near the
drive camera.
One final piece of info - I live by a electricity sub-station - it lies
less than 100m at the end of my garden. If "power interference" is an
issue - could it be generated by the sub-station? If so, how do I protect
against this?
Any suggestions on what I might do to alleviate this problem gratefully
received.
|
Do you have outside lights? if so, do the cables run near the CCTV coax?
Paul
--
real is pjw at ntstelcom#co#uk
Landline SMS with a PC www.z-text.com |
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Greg
Guest
|
| Posted:
Fri Mar 11, 2005 1:13 am Post subject:
Re: CCTV Interface |
|
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"Richard Tubb" <richard@netlinktrading.co.uk> wrote in message
news:iLVXd.34671$y25.3761@fe3.news.blueyonder.co.uk...
| Quote: | Hi,
Have had a good google on this subject but can't find any help - so am
hoping somebody in this newsgroup can. I've lurked here for a while and
can't find a more suitable newsgroup that covers CCTV but apologies if
this is slightly off-topic.
I'm using a Geovision GV-250 PC based CCTV recording system. It has two
cameras, one aimed at my drive and another at my front garden. Both
cameras work fine during daylight but after dusk start displaying what I
can only describe as "rolling white lines" that interfere with the display
and the motion detection recording. The display itself stays still, but
hazy white lines roll down across it. This is a larger problem on the
drive than it is on the front garden camera where the white lines are less
bothersome.
I've had it suggested that this is "power" interference. Would anybody
agree with this?
What I find odd is that I have another separate camera (on a different
system) pointed by my front door, nearby the drive, and this also exhibits
the same "white line" problem and it's cabling goes no-where near the
drive camera.
One final piece of info - I live by a electricity sub-station - it lies
less than 100m at the end of my garden. If "power interference" is an
issue - could it be generated by the sub-station? If so, how do I protect
against this?
Any suggestions on what I might do to alleviate this problem gratefully
received.
Regards,
Richard Tubb.
Richard, |
I use the same software, with 4 cameras, and had the same problem in a low
light situation.
The problem turned out to be a bad power supply, which we discovered only
when mag locks on the same supply were weak.
HTH
Greg.
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Bob Evans
Guest
|
| Posted:
Fri Mar 11, 2005 5:23 pm Post subject:
Re: CCTV Interface |
|
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In article <C01Yd.8492$1S4.907983@news.xtra.co.nz>, Greg
<not_here@nospam.com> wrote
| Quote: | "Richard Tubb" <richard@netlinktrading.co.uk> wrote in message
news:iLVXd.34671$y25.3761@fe3.news.blueyonder.co.uk...
I'm using a Geovision GV-250 PC based CCTV recording system. It has two
cameras, one aimed at my drive and another at my front garden. Both
cameras work fine during daylight but after dusk start displaying what I
can only describe as "rolling white lines" that interfere with the display
and the motion detection recording. The display itself stays still, but
hazy white lines roll down across it. This is a larger problem on the
drive than it is on the front garden camera where the white lines are less
bothersome.
I've had it suggested that this is "power" interference. Would anybody
agree with this?
What I find odd is that I have another separate camera (on a different
system) pointed by my front door, nearby the drive, and this also exhibits
the same "white line" problem and it's cabling goes no-where near the
drive camera.
One final piece of info - I live by a electricity sub-station - it lies
less than 100m at the end of my garden. If "power interference" is an
issue - could it be generated by the sub-station? If so, how do I protect
against this?
I use the same software, with 4 cameras, and had the same problem in a low
light situation.
The problem turned out to be a bad power supply, which we discovered only
when mag locks on the same supply were weak.
|
If the predominant night-time illumination source is from street
lighting (sodium or mercury vapour discharge lamps, etc.), remember also
that light from such sources carries a strong 100Hz modulation that will
produce rolling "hum bars" on CCTV systems that are not "mains-locked".
--
Bob Evans |
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Arthur
Guest
|
| Posted:
Mon Mar 14, 2005 3:51 pm Post subject:
Re: CCTV Interface |
|
|
On Thu, 10 Mar 2005 10:58:22 -0000, Richard Tubb <richard@netlinktrading.co.uk> wrote:
| Quote: | Hi,
Have had a good google on this subject but can't find any help - so am
hoping somebody in this newsgroup can. I've lurked here for a while and
can't find a more suitable newsgroup that covers CCTV but apologies if this
is slightly off-topic.
I'm using a Geovision GV-250 PC based CCTV recording system. It has two
cameras, one aimed at my drive and another at my front garden. Both cameras
work fine during daylight but after dusk start displaying what I can only
describe as "rolling white lines" that interfere with the display and the
motion detection recording. The display itself stays still, but hazy white
lines roll down across it. This is a larger problem on the drive than it is
on the front garden camera where the white lines are less bothersome.
I've had it suggested that this is "power" interference. Would anybody agree
with this?
What I find odd is that I have another separate camera (on a different
system) pointed by my front door, nearby the drive, and this also exhibits
the same "white line" problem and it's cabling goes no-where near the drive
camera.
One final piece of info - I live by a electricity sub-station - it lies less
than 100m at the end of my garden. If "power interference" is an issue -
could it be generated by the sub-station? If so, how do I protect against
this?
Any suggestions on what I might do to alleviate this problem gratefully
received.
|
A little more information would be helpful:
- what type of illumination do you have on these areas?
- do the cameras have built-in IR lights?
- do the white lines come on suddenly, or slowly as the light fades?
Arthur |
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Richard Tubb
Guest
|
| Posted:
Mon Mar 14, 2005 11:06 pm Post subject:
Re: CCTV Interface |
|
|
Hi all,
Thanks for the suggestions thus far. In answer to the questions asked:-
I do have outside lights. 1 x 500W PIR (over the drive, the most problematic
area for "white lines") and 1 x 150W PIR (over the less problematic front
garden area). The cabling for these lights doesn't run very near the Co-Ax
Cable for the CCTV at all though. Maybe 3m away and through a brick wall.
The "white lines" on the CCTV show up whether the area is illuminated by my
outside security lights or whether it is dark.
There is a street light reasonably nearby - but it is perhaps a good 8m
away, and I do notice the "white lines" appearing around dusk before those
street lights have come on. The "white lines" come on slowly as the daylight
fades and are most prominent when it's pitch black outside but the drive is
being lit as a result of somebody or something triggering the 500W PIR.
Greg - will take your idea about the cameras Power Supply being weak
on-board. I have a spare I can use with the cameras to see if this makes any
difference. I have a single PSU powering 2 x CCTV cameras, that PSU plugged
into a 4-gang surge-protected from a main socket. Should I be aiming to be
plugging directly into a mains socket in case of power interferance from
other devices on the 4 gang?
Finally, both CCTV cameras have IR lights built in. You can clearly see them
"glowing" from a distance in the dark.
Hope that helps clarify things. Will be most grateful for any more advice or
possible solutions given!
Regards,
Richard Tubb.
"Arthur" <Arthur@nospam.com> wrote in message
news:op.snmgcda7ilotte@home2.mshome.net...
| Quote: | On Thu, 10 Mar 2005 10:58:22 -0000, Richard Tubb
richard@netlinktrading.co.uk> wrote:
Hi,
Have had a good google on this subject but can't find any help - so am
hoping somebody in this newsgroup can. I've lurked here for a while and
can't find a more suitable newsgroup that covers CCTV but apologies if
this
is slightly off-topic.
I'm using a Geovision GV-250 PC based CCTV recording system. It has two
cameras, one aimed at my drive and another at my front garden. Both
cameras
work fine during daylight but after dusk start displaying what I can only
describe as "rolling white lines" that interfere with the display and the
motion detection recording. The display itself stays still, but hazy
white
lines roll down across it. This is a larger problem on the drive than it
is
on the front garden camera where the white lines are less bothersome.
I've had it suggested that this is "power" interference. Would anybody
agree
with this?
What I find odd is that I have another separate camera (on a different
system) pointed by my front door, nearby the drive, and this also
exhibits
the same "white line" problem and it's cabling goes no-where near the
drive
camera.
One final piece of info - I live by a electricity sub-station - it lies
less
than 100m at the end of my garden. If "power interference" is an issue -
could it be generated by the sub-station? If so, how do I protect against
this?
Any suggestions on what I might do to alleviate this problem gratefully
received.
A little more information would be helpful:
- what type of illumination do you have on these areas?
- do the cameras have built-in IR lights?
- do the white lines come on suddenly, or slowly as the light fades?
Arthur |
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| Back to top |
|
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Arthur
Guest
|
| Posted:
Mon Mar 14, 2005 11:17 pm Post subject:
Re: CCTV Interface |
|
|
On Mon, 14 Mar 2005 17:06:11 -0000, Richard Tubb <richard@netlinktrading.co.uk> wrote:
| Quote: | Hi all,
Thanks for the suggestions thus far. In answer to the questions asked:-
I do have outside lights. 1 x 500W PIR (over the drive, the most problematic
area for "white lines") and 1 x 150W PIR (over the less problematic front
garden area). The cabling for these lights doesn't run very near the Co-Ax
Cable for the CCTV at all though. Maybe 3m away and through a brick wall.
The "white lines" on the CCTV show up whether the area is illuminated by my
outside security lights or whether it is dark.
There is a street light reasonably nearby - but it is perhaps a good 8m
away, and I do notice the "white lines" appearing around dusk before those
street lights have come on. The "white lines" come on slowly as the daylight
fades and are most prominent when it's pitch black outside but the drive is
being lit as a result of somebody or something triggering the 500W PIR.
Greg - will take your idea about the cameras Power Supply being weak
on-board. I have a spare I can use with the cameras to see if this makes any
difference. I have a single PSU powering 2 x CCTV cameras, that PSU plugged
into a 4-gang surge-protected from a main socket. Should I be aiming to be
plugging directly into a mains socket in case of power interferance from
other devices on the 4 gang?
Finally, both CCTV cameras have IR lights built in. You can clearly see them
"glowing" from a distance in the dark.
Hope that helps clarify things. Will be most grateful for any more advice or
possible solutions given!
|
I recognise this, and it's why I asked if you had built-in IR lights. I had an exactly similar symptom which occurred after my system had been running for a couple of years. It was a fault in the power supply, which could still provide enough current to run the cameras during the day, but not enough for the extra current of the IR LED's at night. I replace the power supply with another having greater current capacity and it fixed it right away.
Since the cameras are running continuously, I would suggeat that the power supply is rated at least twice the capcity of the cameras with LED's on. If it's running flat out it will inevitably fail.
Arthur |
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Richard Tubb
Guest
|
| Posted:
Mon Mar 14, 2005 11:52 pm Post subject:
Re: CCTV Interface |
|
|
Hi Arthur,
Thanks for the details - I'm certainly going to take your advice and upgrade
the PSU so that it's comfortable enough to run the camera without any
problems.
However... at the beginning of the thread I mentioned that I had a 3rd
camera, pointed at the problematic drive area, but on a completely separate
system which exhibits the same "white line" problem. This camera is a
bog-standard "Argos, plug into your TV through SCART" affair that *doesn't*
have IR built in.
I'll definitely be taking your advice and upgrading the PSU, but I wonder
that if my 3rd camera is affected by these "white lines" too but it doesn't
use IR and is on a separate system... where does that leave us?
Regards,
Richard Tubb.
"Arthur" <Arthur@nospam.com> wrote in message
news:op.snm0ztlzilotte@home2.mshome.net...
| Quote: | On Mon, 14 Mar 2005 17:06:11 -0000, Richard Tubb
richard@netlinktrading.co.uk> wrote:
Hi all,
Thanks for the suggestions thus far. In answer to the questions asked:-
I do have outside lights. 1 x 500W PIR (over the drive, the most
problematic
area for "white lines") and 1 x 150W PIR (over the less problematic front
garden area). The cabling for these lights doesn't run very near the
Co-Ax
Cable for the CCTV at all though. Maybe 3m away and through a brick wall.
The "white lines" on the CCTV show up whether the area is illuminated by
my
outside security lights or whether it is dark.
There is a street light reasonably nearby - but it is perhaps a good 8m
away, and I do notice the "white lines" appearing around dusk before
those
street lights have come on. The "white lines" come on slowly as the
daylight
fades and are most prominent when it's pitch black outside but the drive
is
being lit as a result of somebody or something triggering the 500W PIR.
Greg - will take your idea about the cameras Power Supply being weak
on-board. I have a spare I can use with the cameras to see if this makes
any
difference. I have a single PSU powering 2 x CCTV cameras, that PSU
plugged
into a 4-gang surge-protected from a main socket. Should I be aiming to
be
plugging directly into a mains socket in case of power interferance from
other devices on the 4 gang?
Finally, both CCTV cameras have IR lights built in. You can clearly see
them
"glowing" from a distance in the dark.
Hope that helps clarify things. Will be most grateful for any more advice
or
possible solutions given!
I recognise this, and it's why I asked if you had built-in IR lights. I
had an exactly similar symptom which occurred after my system had been
running for a couple of years. It was a fault in the power supply, which
could still provide enough current to run the cameras during the day, but
not enough for the extra current of the IR LED's at night. I replace the
power supply with another having greater current capacity and it fixed it
right away.
Since the cameras are running continuously, I would suggeat that the power
supply is rated at least twice the capcity of the cameras with LED's on.
If it's running flat out it will inevitably fail.
Arthur |
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Arthur
Guest
|
| Posted:
Tue Mar 15, 2005 1:30 am Post subject:
Re: CCTV Interface |
|
|
On Mon, 14 Mar 2005 17:52:38 -0000, Richard Tubb <richard@netlinktrading.co.uk> wrote:
| Quote: | Hi Arthur,
Thanks for the details - I'm certainly going to take your advice and upgrade
the PSU so that it's comfortable enough to run the camera without any
problems.
However... at the beginning of the thread I mentioned that I had a 3rd
camera, pointed at the problematic drive area, but on a completely separate
system which exhibits the same "white line" problem. This camera is a
bog-standard "Argos, plug into your TV through SCART" affair that *doesn't*
have IR built in.
I'll definitely be taking your advice and upgrading the PSU, but I wonder
that if my 3rd camera is affected by these "white lines" too but it doesn't
use IR and is on a separate system... where does that leave us?
|
Yes, the independent third camera does seem to be an anomaly that I can't explain. If it's accessible in its current position I would suggest a few tests like covering it over in daylight, or shining a bright light in front of it at night, to see whether the effect is induced by a change in illumination or if it's due to an external effect like radio pick-up.
Arthur |
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