higher megapixel camera = less coverage?

wackystuff

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a friend replaced his old dahua ipc-hfw-4300 bullet 3mp 3.6mm camera with a dahua ipc-hdw4631c-a 6mp 3.6mm ..

he's quite disappointed though ..that the image coverage of the 6mp camera is a lot less than then 3mp camera (even though they are both 3.6mm lens).....(changing resolution of the 6mp camera to 3mp didn't help)..he thought with the 6mp camera, that he would get a bit more/around the same coverage of the old 3mp camera...

so what gives?
 

mat200

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a friend replaced his old dahua ipc-hfw-4300 bullet 3mp 3.6mm camera with a dahua ipc-hdw4631c-a 6mp 3.6mm ..

he's quite disappointed though ..that the image coverage of the 6mp camera is a lot less than then 3mp camera (even though they are both 3.6mm lens).....(changing resolution of the 6mp camera to 3mp didn't help)..he thought with the 6mp camera, that he would get a bit more/around the same coverage of the old 3mp camera...

so what gives?
Chinese Market model, so you get less than spec'ed! ;->

ps - would be good to see an example of what you are mentioning.
 

GCoco

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The HFW4300 has a resolution of 2048 x 1536. The HFW4631 has a resolution of 3072 x 2048 at 6MP and 2304 x 1296 at 3MP. So you can see that the the 4300 has a 4x3 image while the 4631 has 3x2 at 6MP and approximately that at 3MP.
 

wackystuff

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yes, it is the chinese market model.. sad thing is that i'm the one that recommended it...
 

mat200

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yes, it is the chinese market model.. sad thing is that i'm the one that recommended it...
Hi Wacky,

Concur with Fenderman - think they sent you a different lens than 3.6mm on that one. ( 6mm )

Probably a good idea to get another 3.6mm lens and redeploy that to another location.
 

tigerwillow1

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With the 4631 having a larger sensor, it should give greater coverage with the same focal length lens.
 

wackystuff

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quite odd..the serial number on camera and box matches and stickers says 3.6mm...

6mm makes sense though...

guess quality control is not what one gets for a ~$60 chinese region camera..
 

geezer

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Possibility: the vendor supplied a 3.6mm lens that was intended for a larger size sensor.
 
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