Color4K-X 6mm FOV vs T5442T-ZE

[karlocikovic]

I plan to replace existing T5442T-ZE with Color4K-X in 6mm, but I'm not sure if FOV will meet my needs.

I read a good thread from Alaska Country (Color 4K-X-6MM vs Color 4K-X-3.6MM (HFW5849T1-ASE-LED) Side by Side Test Images), comparing 4K-X in 3.6mm and 6mm.
Also one good thread comparing varifocal 5442 and fixed lens 5442 FOV (Comparison of a Fixed Lens and a Varifocal Lens Camera's FOV)

I'm not sure if mine calculations are correct:



Does anybody has side by side 4K-X 6mm and T5442T-ZE and confirm me what zoom level results in same FOV?

 

[Ri22o]

If it helps, this is my 4K-X in 3.6mm.

 

[EMPIRETECANDY]

Different focus distance on the 4K and the 4mp cams, the camera pic will be a little different, esp the side items is blurry. So just watch the pic,4K-X 6mm will reach further with narrow views.

4K-X 6mm



5442T-ZE

 

[karlocikovic]

Andy thank on your effort! I see that 5422T-ZE should be zoomed out a little bit, and pointed up, for same FOV. I'm interested what zoom settings results in same FOV?

 

[jarrow]

I'm interested what zoom settings results in same FOV?

Use the Focal Length Calculator

 

[karlocikovic]

Use the Focal Length Calculator

This tool is not useful for comparing different cameras, especially different sensor sizes. Calculations from that tool gave me too wide FOV.

 

[jarrow]

The tool doesn't give you a FOV, it gives a focal length. You can take the focal length, width of the sensor and distance to the place you want to watch and calculate the field of view yourself.

 

[karlocikovic]

OK, but calculated zoom level for desired focal length of 6mm is not true. This resulted in too wide FOV. The 4k-X 6mm should be close to zoom level 1600, and not 807:



Also to consider, post from wopi ("This means the varifocal T-ZE is actually 3mm to 9mm." ):

Dahua T5442T-ZE in-depth review

Hi guys, Today I present you a review of Dahua T5442T-ZE. This model is equipped with 2.7-12mm zoom lens and an excellent 4 megapixel 1/1.8 inch CMOS sensor. Compared to 5442TM-AS-LED and 5442TM-AS models, which I’ve already reviewed, this one has twice as much RAM available. The housing is...

ipcamtalk.com

 

[EMPIRETECANDY]

4K-T 6MM



T5442T-ZE as you required.

 

[jarrow]

I see what you mean, the numbers of the 5442T-ZE are indeed off.

BUT, when comparing different sensor sizes, the focal length doesn't say anything.
To calculate the width of the scene, you need: sensor width, focal length and distance to the scene.
The sensor width differs and sadly Dahua doesn't offer them in their specs (not where I could find it), but I found a post here.

The formula is as follows:
f = (L x w) / W
Where f = focal length
L = length or distance to the scene
w = width of the sensor
W = width of the scene

You can then rewrite this to calculate the W, width of the scene.
If we were to use L = 10 m and f = 6 mm, this would be the width of the scene for both cams:
4K-X = 30,8 m
5442T-ZE = 20,5 m

The width of the scene would be 1,5 times larger with the 4K cam using the same focal length lens, which is a huge difference.
These are of course only valid if the numbers in the Dahua specs are right.

 

[karlocikovic]

Based on Andy's pictures, and mine calculations, 4K-X 6mm FOV would be approximate to 1900 ZOOM of 5442T-ZE:




BTW, based on Focal Length calculator, that zoom level would be close to Focal Length of 10mm:

Correct me if I'm wrong

 

[jarrow]

I don't see how you came up with the green rectangle for the 4K-X 6mm.
Right side seems about right but to the left you almost cut the entire FOV off, I think it should be more like this:


Which is indeed a bit different, but not equal to 10mm on the 5442T-ZE.

 

[karlocikovic]

I don't see how you came up with the green rectangle for the 4K-X 6mm.
Right side seems about right but to the left you almost cut the entire FOV off, I think it should be more like this:

View attachment 157033
Which is indeed a bit different, but not equal to 10mm on the 5442T-ZE.

 

[jarrow]

That one seems to be placed closer by. You need to compare it with the one in post #9.

 

[karlocikovic]

Then also full zoom in 5442T-ZE is not valid... Also in post #9 he wrote 4K-T 6MM.. Does Full Color Turret in 6mm even exist? I don't think so.

 

[jarrow]

No that one doesn't exist. It doesn't look like a 4K-T 3.6mm either, so I assume its a spelling mistake with the X/T. Only @EMPIRETECANDY would know

 

[wittaj]

No that one doesn't exist. It doesn't look like a 4K-T 3.6mm either, so I assume its a spelling mistake with the X/T. Only @EMPIRETECANDY would know

There is a 3.6mm 4K/T.

There is a 6mm 4K/X.

There is no 6mm 4K/T

 

[digger11]

I'm planning on replacing a t5442t-ze with a 6mm color4k-x on Saturday. I'll see what I can do around capturing some comparison images.
Give my your best estimate of the zoom level on the ZE that will match the 6mm FOV and I'll make sure to capture stills at that zoom level along with a few zoom levels -/+.

 

[105437]

Really impressed with the 5442 picture quality compared to the 4K-T.

 

[wittaj]

Really impressed with the 5442 picture quality compared to the 4K-T.

Many here say 4MP is more than enough in the surveillance camera world and the 5442 is still the overall king since that series has varifocals.

But to be fair, the larger sensor of the 4K cameras also has a tighter, more defined focus distance and I think that example above is on the short end of the optimal distance focus for the 4K.

But where the 4K/X and 4K/T shine compared to the equivalent 5442 fixed cam is that a lot less light is needed for the 4K/X/T compared to the 5442.

So for many with challenging light conditions, but want to capture in color, the 4K/X/T is probably the better choice.

But for someone that is ok with B/W or that wants optimal capture regardless of whether it is color or B/W with infrared, then the 5442 is probably the better choice since it can see infrared whereas the 4K/X/T cannot.