Missing footage during playback

[Baspinall]

I have a Hikvision 9632NI-ST NVR installed at commercial customers building. Last Thursday someone ran off the road and through the property tearing up the lawn. I went to retrieve the footage and that portion is missing? I know that I have heard that this can happen if you use PC hard drives in the NVR. These hard drives came from Hikvision installed (two 6 GB) not sure which brand they installed. Obviously there is no way to retrieve the footage for my customer at this point which does not look good on me. Any thoughts as to what is going on?
I have also noticed that when I enter the playback mode there is no events listed for a few days on a couple different cameras. I know that they are set up for motion only recording. Nothing on a couple cams for two days? People are working here so I know there is motion going on. Current Firmware on the NVR is V3.4.2.

 

[nayr]

Your recording on motion thats the problem; record continuously and you wont be in this boat next time.. it has nothing to do with the HDD's you used and everything to do with the way you configured motion.

 

[Baspinall]

But if I record continuously I will burn through HD space way quicker. I was trying to get at least three to four weeks recording. Or am I missing something here? I have 15 cameras with 12TB HD

 

[nayr]

disk space is cheap, I get 3-4 weeks w/my 8 cameras off 10TB.. so you need at least 2x what you currently have..

Do you have legal compliance reasons for that much archive? Ive never needed to retrieve footage past 2 weeks even through I have the capability..

You can reduce bitrate and/or use VBR or more efficient encoding (h265) to reduce disk usage.. motion detection will just miss shit and then whats the point of even having cameras

 

[Baspinall]

I get what your saying but. Why does motion miss things? What good is that setting if it doesn't work

 

[nayr]

because you set it up without proper testing; it was not constantly triggering.. kinda hard to test a car driving through a wall unless you want to do it a few times while tweaking the settings.. probably happened far too fast for it to be registered.

motion detection is good for flagging your timeline so you can find activity without watching days of video at high speed; other than that its not worth much anything at all.

 

[Baspinall]

Actually we do test them to see that they trigger in motion. This was a car that drove right through the iddle of the field of view, stopped there and a woman got out and walked away then returned. Another camera caught it but at a bad angle. So again, I don't understand why this particular camera even though set on motion did not. The event happened at 12:36. When I play back this cameras footage it jumps from 12:35 to 12:39 missing everything.

 

[Baspinall]

I can set all the outside cameras to continuous I guess but still don't understand why it did what it did.