5 in total at the end.. farthest would start at one, then 2.. then goes up as it gets closer to where its combining and to NVR
I would then start with a 3/4" pipe to a junction box for the first drop, a 3/4" to the next, then finish with the 1/2' EMT.
As the junction boxes from Dahua take a 1/2" EMT pipe - I would add that to the drop.
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Hopefully the above ascii art works...
( it did not, so I added "." for spaces )