Questions about IP cameras with SD cards

[Joeinamillion 0]

Do cameras using SD cards...

 

1. use the SD card to work like a DVR for each camera?

2. overwrite data on an ongoing basis?

3. save much time on a 32gb card? (7fps - 30fps, & 720p - 3mp, compression etc.)

4. need a 10x (high end) brand name (Lexar, etc) sd card, or can a 'no name' cheap card be used?

5a. stop recording, and retain (keeps) it's lastest data, if it loses contact with the IP?

5b. use SD cards as a fail safe device for NVR, FTP, etc?

6. report missing or SD card read/write fails (for aging, damaged, or stolen cards)?

7. loses power will the last file it was writing be readable?

 

With regards to question 5. If the camera loses power of course it will retain it's data and stop recording, but if it's not PoE, or if the PoE is injected and only the IP connect is lost what happens to the cameras ongoing recording? (Ie. Camera supports 12v separate power, or user has injected PoE near the camera and the NVR, switch, or router are disconnected (stolen)?)

 

I'm trying to decide if SD carded cameras are worth it. I mean it would be upsetting if you needed the SD recording, then found out any one of the above issues made the feature useless.

 

...and at #6 stolen SD card, I mean... really? The visual image had me ROTFLMAO!

[buellwinkle 0]

1. Some brands do this better than others, some do it different. For example Hikvision and Dahua have playback on the camera itself. The advantage is as long you can access the camera via the browser, you can play recorded video back in a similar fashion to an NVR, but one camera at a time. Some like ACTi and Axis have Windows programs that consolidate the cameras, so you can view a group of cameras, like 4 cameras like an NVR would and typically allow playback of one camera. The app only runs when you want to view cameras, so not the same as NVR software that's actually doing the recording.

 

2. Yes

 

3. Depends on the situation. I have SD cards in my cameras at our vacation home and the only time it gets triggered is when I first enter the home, then unplug them while I'm there. Has a 16GB card that has yet to fill up.

 

4. I always had the best luck with no-name cheaper cards. The faster 10x or faster cards have issues sometimes. I've put expensive sandisk high end cards in cameras and works with one camera, not another brand camera, yet the cheap cards work on everything. When I say cheap, I don't mean go to China and buy them for $1 each.

 

5. It will only stop recording if you turn the camera off or pull the SD card out or set an option not to record. If you lose power, clearly it will stop recording. Get a UPS for the PoE switch, cheaper than getting a UPS at each camera location and I can't imagine not having a UPS for your networking equipment because to me, they are the most sensitive to power issues, lost several switches & routers over the years, even Cisco, so absolutely do this. You can also plug in your PC to the UPS.

 

6. Depends on the brand and model. Some have an alarm (just happened to me on a Hikvision camera I was reviewing. I put the SD card, the alarm beeping went off really load until the format of the card started).

 

7. If you lost power while writing a file, I would assume that file would be corrupt. I use a UPS to minimize that from happening, at least to bridge momentary interruptions, although not like a server where you can have it do a graceful shutdown when the UPS signals an outage.

[MaxIcon 0]

If you do have file corruption problems for whatever reason, those can slowly fill up the card until there's little room left for recording, and the card will need to be formatted. I had this happen on one cam, and you always discover this at the critical time that you need the backups recordings!

 

So, if you use SD cards, it's not a bad idea to check them or format them regularly.

[Joeinamillion 0]

If you do have file corruption problems for whatever reason, those can slowly fill up the card until there's little room left for recording, and the card will need to be formatted. I had this happen on one cam, and you always discover this at the critical time that you need the backups recordings!

 

So, if you use SD cards, it's not a bad idea to check them or format them regularly.

 

The above is so true.

 

It raises another question, can the SD card be formatted in the camera. And can all files, corrupt ones too, be copied from the card for attempted repair on a PC?

 

The only time I'd want to have to physically remove a card would be to replace it (they have a limited number of writes), or to use the physical card for legal reasons.

 

Does anyone know if any IP cameras use XD (64GB+) cards yet?

[MaxIcon 0]

All the cams I've tried have allowed formatting the cards in place, but firmware can be unpredictable. The big names should have no problem with this.

 

To do any kind of corrupt/damaged file recovery, you'd want to remove the card and plug it into a PC. Some are easier than others to get at; most of mine are quite a pain to remove.

 

I don't know about the capacity issues. I quit using SD cards some years ago because of how much trouble they were (though multiple cams still have them installed), and support has progressed since then.