Lens size

[carcol_123 0]

I have installed a Samsung SCB-2001p with a 3.5 to 8mm lens over my garage, the 8mm side of the lens is not quite big enough so is very slightly out of focus, before I had a 2.8 to 12 lens, should I stick to this size lens or should I go larger and would this make it easier to focus, with a larger lens. Will wait your response. Colin

[myiicu 0]

Some vari-focal lens have difficulty maintaining optical correction throughout the zoom range.

As a result, focus can suffer at the extreme ends of near and far.

 

Going with a larger vari-focal lens should help but keep in mind that your fov will be reduced.

 

For low light, a day/night ir corrected lens with f1.0 or f1.2 is recommended.

 

Computar, Fujinon and Tamron are better brands.

[carcol_123 0]

I have found a Computar cs 5-50 lens it is f1.3 would this lens be ok for a good night vision

[myiicu 0]

That Computar 5-50mm f1.3 lens is not day/night IR corrected.

This will result in some focus shift from day to night use.

 

The Computar TG5Z8513FCS-IR is day/night IR corrected

8.5-40mm f1.3

[carcol_123 0]

Can I be cheeky and ask if you know the equivalent lens made by Fujinon and Tamron, you have been a great help so far Thanks Colin

[myiicu 0]

Good 1/3" low light lens (non-MP):

Day/Night IR corrected, vari-focal, dc auto iris

 

Computar TG5Z8513FCS-IR

8.5-40mm

f1.3

 

Computar TG3Z2910FCS-IR

2.9-8.2mm

f1.0

 

Computar TG3Z3510FCS-IR

3.5-10.5mm

f1.0

 

Computar HG3Z4512FCS-IR (This is 1/2" lens)

4.5-12.5mm

f1.2

 

Fujinon YV2.7X2.9LR4D-SA2L

2.9mm-8.0mm

f0.95

 

Tamron 13VG308ASIRII

3-8mm

f1.0

 

Tamron 12VG412ASIR-SQ (This is 1/2" lens)

4-12mm

f1.2

[myiicu 0]

Samsung SCB-4000 with 80mm lens