kiwibird
n3wb
- Dec 21, 2016
- 26
- 2
I have one 1-Dahua HDW5231Rp-Z Starlight (and happy with it) but wouldnt a hfw4431r-z be better. Light levels lower and price a lot lower too.
guykuo
Getting comfortable
With a limited zoom 5X, the hfw4431r-z would be okay for LPR out to about 25 yards based on what I've experienced.
The 4431's minimum lux ratings should not be better than the 5231's. But since Dahua made the 4431 only for sale/use within China, AFAIK nobody's been able to find the "official" Dahua specs for this model. The entrepreneurs that resell the 4431 outside of China (after loading on a hacked firmware, as the official Dahua firmware for this model is in Chinese only) are known for putting their own specs in their ebay/AliExpress/etc listings.
Not saying this camera won't work for LPR, but from reading the reviews of it in this thread, it doesn't seem to perform as well in low-light as the 5231. Makes sense .. it has a smaller image sensor combined with a higher MP lens ... that combination works against having better low-light performance than the Starlight models (like the 5231). It all comes down to how bright your scene will be... The darker it is, the better the 5231 should do vs. the 4431. Check out @nayr's comments in post #12. That thread also has some comments from folks trying to use this 4431 as a LPR camera.
Remember that the inexpensive "Chinese-market only" models (like the 4431) require some special consideration. Normally you can not upgrade the firmware that comes on them. This may not seem like a big issue, but the latest 5231 firmware upgrade added a feature that I think might be useful for LPR -- the ability for the camera to switch between day/night profiles automatically, based on how bright the scene is. Also, if you're planning on recoding to a Dahua NVR, the latest NVR firmwares block the 4431s. Not dealbreakers for some, but definitely anyone considering one of these cameras should be aware of (IMO).
mat200
IPCT Contributor
- Jan 17, 2017
- 15,034
- 25,343
@kiwibird indeed concur w/Aristobrat do NOT trust the specs claimed on any Chinese market models... in fact, do not trust specs sellers put up - verify always when using specs to determine your purchasing options, and follow up by reading the reviews and recommendations here.
guykuo
Getting comfortable
Better yet.... just get them from Andy. I've done that for about 8 cams now. He always comes through.
hmjgriffon
Known around here
Francisco73
Getting the hang of it
How to verify the specs sellers put up without buying and testing the product? My limited experience from Ali is that all sellers are making same claims.
mat200
IPCT Contributor
- Jan 17, 2017
- 15,034
- 25,343
Hi @Francisco73
The easiest is to go to the Dahua International website and pull up the spec sheets - while they're certainly not perfect, they represent at least a standard by which Dahua presents to it's partners and potential customers.
For those who do this for a living, IPVM probably has some good info also - though many of us are not in the business, we're what would be called pro-consumers.
Francisco73
Getting the hang of it
The sellers often repeat what Dahua has on the website and this may not be correct. I have Starlights with 64mm varifocal that according to Dahua offer 88m identification daytime. Must be a person with a really big face or hopefully I need more practice zooming and setting up the cameras. Thanks.
mat200
IPCT Contributor
- Jan 17, 2017
- 15,034
- 25,343
Hi Francisco
I think Dahua ( and others ) use the most "beneficial" planning numbers when determining their DORI ranges / distances. They certainly do not use 100 ppf / about 300 ppm - but a far lower pixel density when calculating their stats.
So, think of the numbers as a way to compare one Dahua product vs another Dahua product.
Are you saying the 4431r-z does better in low light? I have both the 4431r-z and a 5231-z and can tell you that the 5231 is way better in low light. I'm not putting the 4431 line down. They are good cameras with great daytime images. They just don't have the night sensitivity of the starlights. I was using a 4431r-z for lpr and switched to a fixed-focus 2mp starlight for the better night performance. The new day-night profile switch aristobrat pointed out is big. I've found that the exposure settings to get night lpr yield a lousy daytime image. I see it as a simple cost vs. capability issue. If you need only the good day image, the 4431r-z is a great deal. If you need a better night image, pony up the bucks for a real starlight model. I posted sample images in these threads:
Comparison of IPC-HFW5231E-Z and IPC-HFW4431R-Z
Comparison of mini bullet HFW-4231E-SE with 3 other cameras
Francisco73
Getting the hang of it
What's the firmware version in your nvr? As of May this year, the latest 5xxx-4ks2 firmware was V3.215.0000001.0.R.20180326.
Francisco73
Getting the hang of it
I am new to this and just ordered 3 5231's and a poe 4208 nvr. I see the cameras have a sd card slot. How does that work and do I need them?
Thanks, Joe
Thanks, Joe
Taking apart the 5231s and putting in a SD card gives you the ability to record to the SD card as well as the NVR. If someone steals your NVR (but leaves the cameras alone), there could still be video recordings on the SD cards. I'd guess that few people here do that, but the option is there.
Francisco73
Getting the hang of it
Does the SD card also not make it possible to record without using NVR and having PoE as long as there is another power source?
Yes, you should be able to plug in 12v power (or use a PoE injector/switch) and not use an NVR at all. I've only done this once with a Hikvision camera, not Dahua, but I'm sure the experience is similar.