Pentaplex Power Telecomm PDVR-8300

[intelli-home 0]

http://www.powertelecomm.com/

 

I just received and setup the Power telecomm PDVR-8300. It seems to be a nice machine but that's coming from someone who has not installed many DVR's. I had a need for 4-5 channels so decided on the 8ch unit although the 8 ch unit only has 120fps. I went with it anyway because you can set up each channel for it's own resolution and FPS. So in my case ch 5-8 are not used so I set them up for 0 FPS. The unit keeps track of "remaining available speed" So you can mix and match any combination of resolution and fps for each camera. If you select too much your "remaining available speed" shows "ERR", so you have to lower one or more cameras fps or resolution.

I was very surprised to learn that only one channel can be set to record at full res (720X480) and 30fps. All other 7 channels must be set at 0fps and 360X240.

So with channels 1-4 setup at 720X240 at 15fps each. I have no available fps for cameras 5-8. The best I can record across all 8 channels is 360X240 at 15fps. My question is...Does this sound normal? In other words looking at the spec sheet the system says 120fps (grant it that's only 15fps per ch as adverised but I figured I'd set ch. 5-8 to zero fps and I'd have 120fps or 30fps across ch.1-4) The resolution states 720X480 or 360X240. Turns out I have to set the resolution to the lowest setting to get 30fps across 4 channels. I'm just trying to understand if most middle line systems (I'm assuming this unit is "middle line") are setup this way or is this really a bottom line system that I was duped or naive into thinking was better then it is?

I have to admit the system works very nice and the playback looks great at 360X240 at 15fps. The video looks great on a LCD and over the internet. So I'm not unhappy with the unit just wondering if I should have known by the specs that only one channel was capable real time recording.

Thanks!

Kevin

[Thomas in BP 0]

Kevin,

 

The short answer is that if you get ~15fps per channel on 8 channels with your 120/100fps device, then, yes, it sounds absolutely normal.

 

If you see a manufacturer mention the speed of their device in only fps (120/100fps in your case), then you can assume that it is the fps at CIF (NTSC: 352×240, PAL: 352×288) or half-D1 (360x240) resolution. As far as I know, CIF used to be the standard analog storage resolution while half-D1 is the digital equivalent. The standard output of an analog NTSC/PAL CCTV camera is actually 2CIF (NTSC: 704x240, PAL: 704x288) which corresponds to D1 (720x240), the full resolution for digital storage. That is why you will get half the fps mentioned by the manufacturers when you want to record full resolution.

 

A typical A/D converter chip can handle 120/100fps (NTSC/PAL) in CIF, so if you see a device advertised with those figures you can be relatively sure that it uses one A/D chip for all the channels - in your case 8 channels.

 

BNC connectors are relatively cheap, so the price of a device/capture card is normally not based on the number of channels, but rather on the number of A/D converter chips and other components, so you always get what you pay for - in terms of performance, image quality, and build/hardware quality. In my opinion, it does not make much sense to judge a system solely on the fps performance, because you can easily have a high-end system designed to deliver 1 fps per channel if that is what the customer wants and you can also have a low-end system designed to deliver 15 fps per channel. Image quality is relatively easy to judge, but you should always judge it on the quality of the playback, because on a system with 'real time monitoring' feature it simply loops the input video directly through to the monitor, so what you see (on your monitor) is not necessarily what you get (on your harddrive)!

 

The build/hardware quality is more difficult to judge, as that is dependent on the electronic components chosen, but again price is a relatively good indicator. As I am not a techie, I judge build quality on whether the soldering and layout looks 'clean' and then I focus on the condensators (maybe capacitor in English?) on the PCB as that is the easiest way for a non-techie like me. If the condensators have a blank surface on the top, then they cost two-three times as much as the condensators with three lines engraved in a star shape on the top. Of course the more expensive condensators will have a longer life with reliable performance and a manufacturer who spends extra on the condensators is not very likely to have picked the cheapest A/D chips etc. That is the logical deduction I use in lack of deep technical knowledge about electronic components!

[intelli-home 0]

Thomas,

Thank you for taking the time to help me to get a better understanding of the "DVR". Your explanation helps a lot.

It appears that's it is not an easy task to determine what your getting in terms of a quality DVR. Although at least knowing the basics helps rule out a good portion of them. I've just always found it difficult to pay a high price for a product and assume it must be good because of the cost. Although, a DVR seems to be one of those items.

 

Thanks again!,

Kevin

[BurstElement 0]

You're pretty much on the money there Thomas... CIF is pretty much the CCIR broadcast standard for analogue video and D1 is the broadcast standard for digital video.

 

To me 100IPS @ CIF for an 8ch is half the speed I would expect to see, however, we are seeing more and more consumer / prosumer / povstaller hardware these days and it's sort of coming down to a question of what do you need vs what is good / bad.

 

Basically I would put it down to price... if you (yourself) are happy with the price as defined by your region (I expect that would go for ~250-300US but your market will differ) then go for it.

 

Also although I've never seen that unit / brand before it smells like an Avtech product... either OEM or copy and running at half the speed.

The reason I say that is simply because of the layout of their spec sheets and the "pentaplex" BS which if anyone has read the box and considered what they are claiming would realise it's just marketing BS.