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Old September 18th 17, 09:14 AM posted to uk.railway,uk.transport.london,misc.transport.urban-transit
Roland Perry Roland Perry is offline
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First recorded activity at LondonBanter: Aug 2003
Posts: 10,125
Default Explosion on district line

In message , at 20:05:01 on
Sun, 17 Sep 2017, Charles Ellson remarked:
On Sun, 17 Sep 2017 09:40:01 +0100, Roland Perry
wrote:

In message , at 03:29:35 on
Sun, 17 Sep 2017, Charles Ellson remarked:
But instead of the early grainy, very low res, fuzzy, extended play VHS
images on worn-out tapes, it's now HD quality, sharp, clear, digital
images. Perhaps some are now 4k video quality?

How many would sir like ?
https://www.cctvcameraworld.com/4k-ip-cameras.html

I wonder how widely installed those are? Most installed cameras are well
behind the state-of-the-art.

At around 200 squid a time possibly roughly the same good/bad quality
spread among users applies as before when it seemed to be "TV" quality
v. something cheaper ?


The cost of CCTV systems is much more than just a consumer grade camera.
For public surveillance not only is there the backhaul, but they are
often able to pan and tilt, and need much better sensitivity/
illumination than those listed.

Have you actually installed and used those cheapo ones? They are OK for
the passageway down the side of a shop, but not much else.

There's not much point having pan and tilt if you haven't got someone
to operate it; the "do you know this person?" pictures generally seem
to come from fixed cameras.


Tell that to the installers of the tens of thousands of cameras which do
pan and tilt.

The need for moveable cameras is reduced by siting fixed cameras at
pinch points;


The moveable cameras tend to be at strategic points where they can cover
may different routes. The panning and tilting can be automatic on a
timer. Such cameras are more for preventing crime than detecting it.

each moveable camera is likely to augment several fixed cameras
depending on purpose. When you get to the point of needing to track a
specific target then you probably are needing more moveable cameras
(and zoom lenses).


You've been watching too much "Spooks".
--
Roland Perry