Dahua 3841T-S vs Dahua 3841T-S2 - bad quality - hardware problem?

[Speed666]

Hello,
I just compared two cameras as mentioned before. I bought 8Mpix ones. On one site i had to lower both profiles to 1920x1080 because of NVR limitation and bandwidth problem. I suddenly realized that S-series cams has real problems with firmware or hardware in quality when 1st profile is not set to 4K.

It is clearly visible on comparsion below. Latest firmware upgrade doesnt help. Looks like bad scaller inside first S-series cameras. Any clues? S2 with CHIPUP CPU works well. Sigmastar based produces bad quality.

On both pictures i play "Third Stream" setup as 1920x1080 on every time. On S-series - when i setup 1920x1080 on Main profile - playing back Main Profile also looks as bad as on the right side. What the heck?

 

[wittaj]

I say here often when people ask if downrezing a camera is the same as purchasing the lower resolution camera and the answer is usually no.

The firmware will make some algorithm attempt at downrezing it, but it could be a complete crap image or a somewhat usable image, so we always suggest if the NVR is the limitation and one doesn't plan to update the NVR, then buy a native resolution camera instead of downrezing a higher MP camera.

This looks like a camera that falls more under the crap image if downrez.

 

[Speed666]

But the problem is more complicated. If i setup resolution higher that 1920x1080 on Main stream - the problem doesnt show - works well.

Real problem is that i need to use those cameras in Corridor MODE. And limitation is that i can only use 1080p resolution then.

 

[wittaj]

Yeah I think it is taking whatever the mainstream is and using that to downrez, but it must be a % reduction or some other crazy attempt because it appears to take the 1920 mainstream and downrez that even though the 2nd stream is the same resolution, so it is downrezing regardless of what main is set to?

 

[Speed666]

Nope. Both Main and Sub looks like this - very bad. What the hell is wrong here? Different resampling method?

 

[Speed666]

Next resolution in list fixes problem. But then i cannot setup Corridor Mode....