Tips for Dahua coaxial and IP systems

[maguro]

Hi everyone, I'm planning to redo the CCTV system in a house. I already have the old coaxial cables that I'd like to use for 7 cameras, and I'd like to add an IP camera.
My idea was to go with Dahua, specifically the dual-light turret models like the HAC-HDW1239T-IL-A-S2 (2mp) or HAC-HDW1509T-IL-A-S2 (5mp)
I'm actually undecided between these models. I'm worried that, having the same sensor, the 5MP model might be too noisy at night, but I'm also worried that 2MP is a bit low.
What do you recommend?
As for the IP camera, I was considering an IPC-HFW2449T-ZAS-IL to have the varifocal lens, as it's in a more sensitive area.
Let me know your expert opinions.
Thanks

 

[wittaj]

Welcome!

You are correct, a higher MP on the same size sensor as a lower MP camera will result in poor night time quality.

With the right focal length, 2MP is sufficient for most.

Most go by this chart. Anything in green is what you want:

 

[TonyR]

Thte 4MP IP cam you linked has a sensor suitable for a 2MP camera....if you want 4MP, get at least a 1/1.8" sensor, as shown in the above chart.