phred

Dome covers are one of the biggest culprits for low quality and other image issues when dealing with Vandal Dome Cameras. They also tend to get scratched easily, so make sure to use a distributor that can supply you with the specific dome covers sold separately; they typically differ in size/shape from one model to the next. Otherwise you will be up the creek without a paddle when there are no "clear" spots left on the dome cover.

Problem is even worse for those domes with the black inner shell with a small cutout for the lens to see through. Often the shell is fixed, so you can't move it round and get a fresh unscratched area – would like to meet the genius that thought that up .

A possible solution that has worked for me on a few occasions is to polished out minor scratches with car polish, not the ordinary wax but the stuff used for restoring the paint finish. You would need to test different brands as some are more aggressive than others. Can also be used for polishing out scratches on DVDs.

gthms That's what I call a proper 'belt and braces' approach.

Have also used metal halides with very good results. High efficiency and give the best natural colour if you select appropriate colour temp lamps. Available in much higher power than CF if you have a large area to cover.

I also use auto switching via dusk-till-dawn photocells on the CF floods – nice to know you can light the place up all night without feeling guilty about cooking the planet.

Take a look at our ICR-10XDN

Not trying to self promote here, but it is an excellent all-in-one weatherproof camera.

 

Are these available anywhere in the UK?

Just discovered that Samsung make some DVRs that may allow you to do what you want.

Samsung GV-EM130DD - DVR with removable hard drive and DVR reader software you install on a PC to allow you to view the files directly from the removable hard drive. But only one channel.

So such things do exist.

No idea how good they are though.

one of my friend suggest to purchase hdd reader for viewing hot swap hdd on laptop , but neither i nor he is sure about this . please advice

as this will helpful in solving the problem of many small retailers like me .

Do not know of any standalone DVR that would allow you to do this. Many standalones are Linux based so disks are formatted in an entirely different way to a windows PC. Even with those that use FAT disk formatting, the files are written in a proprietary format with a proprietary codec and some also use encryption. Some DVRs allow you to export the video to removable storage in a form readable on a PC but often the files need to be transcoded first and this can take a very long time.

If you are going to need a recorder at each site then I would go with blowrabbit's suggestion and buy an extra one to keep at home. You will get the benefit of the DVRs rapid 'search for the interesting bits' facilities.

try googling 'integrated automated remote digital image collection'

also Harbortronics may have what you are after

Setting up IR lighting can be tricky as the light tends to be harsh and bleaches out detail, it really needs to be bounced of something to make it more diffuse. Works best with plain B&W cameras imo.

Often overlooked but worth considering is putting up some compact fluorescent lamps. CF lamps are still the most efficient form of lighting and you get a lot of light from a 9watt lamp or 24watt floodlight. I get nice clear recordings from my day/ night cams using this approach. Cheap to run, lamps last for years and backup power requirements are minimal.

Many standalone DVRs write data on the hard drive in a form that cannot be accessed directly by a PC as deliberate security measure to avoid tampering with evidence.

Many now have the facility to output recordings to a USB drive or dvd recorder, sometimes this can be viewed on a PC with appropriate viewing software.

Suggest you look for the facility to output only the motion alarm recordings as sitting through several days continuous recordings from 4 cameras is similar to watching paint dry and guaranteed to send you to sleep.

OK. so your requirements cover everything from the very demanding casino to the very modest bank vault. You also mention NVR and DVR so I guess you have a mixture of analogue and IP. No company imo has the best recording solution of-the-shelf for all situations.

Choosing the right codec for each task is important. Jpeg2000 still offers the sharpest image quality but requires many times the storage capacity of H.264. Considering your storage requirement, getting this wrong could break your budget.

Problem with mobos is they rush them out the door before the job is done then spend six months sorting out the bios bugs. I never buy the latest thing for that reason.

My home dvr system has a core 2 duo 6200 on an Asus mobo – totally over the top for the Vguard RT4 card.

When I first put the system together and powered up I though I had a serious problem as the CPU fan revolved a few times then stopped. Turns out that is all the cooling it requires. Even running as a dvr with four channels at D1, 25fps per channel I only use 4% cpu so the processor fan rarely turns. Makes for a nice quiet machine and the lack of heat can only be a good thing long term.

Anyway , thanks for sharing your experience guys. Looks like we have come to similar conclusions quite independently.

Apologies to anyone who feels I hi-jacked the thread.

Rory

I could not point my finger at any particular brand of PSU, most I have had to change have one common trait though– lightweight. By comparison, you don't want to drop an Antec on your toe.

Obvious answer is 'a very large one'

It would help if you gave some more specifics like-

how many fps at what resolution

preferred compression codec

Any 'must have' features

Perhaps a topic for a new thread but i'm a neub here.

What do you guys prefer for power supplies?

I have probably seen more PC power supply failures over the years than hard drives.

I now use nothing but Antec for my own builds – no failures so far.

Sparks – hold on. I will jump in my time machine and zap forward 5 years then come back and tell you how hard drive reliability panned out!

Joking aside – your guess is as good as anyones as to what will turn out to be the most reliable of the current crop of drives as they have not been tested in the real world for very long. If I knew of a drive model that had run for many years with zero failures it would be irrelevant today in terms of performance and capacity.

Based on passed experience I would suggest any model Seagate with the capacity you are after and relax with the 5 year warranty.

Motion detection with lots of cams may not always drive a cpu to its limits, it depends on the dvr or dvr card. With a geo 1480 for example the chips they use have in-built motion detection, which is why I think geo has now got two seperate motion detection bits (ie standard and advanced). If I recall (its been a while since I read the chip specs) the onboard chip is capable of fully handling the standard geo motion detection. It also explains why the two are seperate, and not one and the same. One they added because it was easy to do, the other they added due to the first not being up to scratch....

 

As for motion detection, I use it, but I also have a permanently recording backup dvr, as motion detection always seems to be fine, apart from now and again when its not... Hard to figure out why, or to reproduce, but its never perfect for me.

I take a similar approach.

The UK law on evidence states that evidence must be complete and not an extract, so motion only recording is open to a challenge.

Motion only recordings are not inadmissible in UK courts but advice is to record continuously.

Advice to police when submitting cctv evidence from public areas is to include recordings 10 minutes before and after an event.

Don't mean to hijack this thread but has anyone used samsung drives for thier dvr? How do these compare?

Have built a couple of dvrs with Samsung spinpoints. Nice quiet drives but too early to tell how they will fair longterm – oldest has been up for 11 months with no problems (left hand moving to touch large piece of Oak!). Overall my vote goes to Seagate - they don't give a 5 year warranty without good reason.

Is there a general knowledge method to identify a DVR board as having hardware encoding /compression on it (as opposed to software compression)?

 

In addition to the conexant fusion 878a chip, there must be a MPEG or H.264 encoding chip dedicated to do this, perhaps one per channel or MUX.

 

 

I'm in the amateur side of things, 4 to 8 channels, looking for solutions.

 

Please expand my brain.

Bt 878/879 chip is only an ADC so compression has to be done by something else - the cpu unless you have hardware compression chips.

Hardware compression cards use additional digital signal processing chips like TI DM64x to do compression. With something like H.264, motion detection is part of the algorithm.

From experience - the big benefit of using a hardware compression card is stability as the cpu is left with very little to do.

I have used Vguard RT4 cards with very good results - recording all four channels at 704 X576 25fps using H.264 compression uses only a few percent CPU

These cards are expensive in the US but much cheaper in Europe