New IPC-Color4K-T is Out of Focus.

[ThomasCamFan]

I just added a third IPC-Color4K-T (3.6mm) to my Dahua NVR. First two have been in service for a few months and have very nice images. But the new one is slightly out of focus. Drat!

All three are using the same settings.

The camera is still within the Amazon return window. I have a week to return it if that is the recommended solution.

However, I would rather fix it myself. But only if doing such a thing does not cancel the warranty. And only if the lens is not factory glued in place.

Basically I'm seeking advice on the recommended solution for camera focus problems.

- Thomas

 

[wittaj]

It is easy to do. It is glued but comes off easily.

 

[ThomasCamFan]

I disassembled the camera and found the lens fully contained inside a protective barrel. I tried pulling off the barrel piece, but gave up before I broke something.

Time is running out -- My 30 day return window ends in two days. So I am taking the easy way out and will return camera. I did a factory reset, repacked in as-new condition, and now have a Amazon return label. My apologies to Andy for having to do this, but it is disappointing to get a poorly adjusted camera.

It would be nice to know how to safely adjust the Color4K-T lens in case this happens to me on the next camera. For reference, attached is an image of what I ran into. The barrel hides the lens; how do I safely take it off and adjust the lens without affecting the camera warranty?

- Thomas

 

[Photon Farmer]

I have a few of these cameras.
Picture with depth will not all be in sharp focus at different depths.

Using your picture to adjust focus remove two patches of clear glue on circular threaded area(red arrows).
Before removing glue, I use sharp light grey felt pen to, make an alignment mark from base onto lens barrel.
To remove glue I use a tool similar to an ice pick with a bend behind point.
I put camera on bench and setup a target at minimum focus I want.
Hold base(purple square) still - twist lens barrel(yellow circle) small amount - check focus - repeat.


Picture below is with a 3.6mm lens.
This cameras function is to cover doorstep, only!!
This camera gives a sharp picture only for a limited depth of field.


Look at building in background, this camera is a timestamp.
If you want focus for a large change in depth of field - get a different camera.
To me this camera is great for lowlight overview, or limited area of closeup.

 

[Oneup]

I wonder if this depth of field focus issue is only on the 4K color version, or is it on all the newer 4K cameras?

 

[bigredfish]

I think anything with an F1.0 lens will have some, (there's a few photog guys around here that can better explain why)
but I have found the bullet version 4K-X (3.6mm) is not nearly as bad

 

[ThomasCamFan]

@Photon Farmer, thanks for the detailed instructions.

I received the replacement camera today (ordered it before my Amazon return). Previous version was 3.6mm (my preference), but I replaced it with 2.8mm. I suspect focus looks better to me because the 2.8mm has a shorter minimum focus zone (1 meter less).

From what I can tell, the IPC-Color4K-T 3.6mm has a minimum focus zone of about six meters, maybe more. That is a very long distance! Anything less is blurry. But as mentioned by Photon Farmer, it can be optimized if necessary.

- Thomas

 

[bigredfish]

6 meters?
Its less than 1/2 that distance to the bags and wheelbarrow on the left of the image above from the 4K-X

And was exactly 10ft to the bumper of the Toyota in the other image

 

[ThomasCamFan]

6 meters?
Its less than 1/2 that distance to the bags and wheelbarrow on the left of the image above from the 4K-X

I checked the Empiretech data sheets:
IPC-COLOR4K-X with 2.8 mm lens has 3 m (10.2 ft) focal depth. {That is confirmed by your photos}
IPC-COLOR4K-T with 2.8 mm lens has 5 m (16.4 ft) focal depth. {Mine seems a little bit further than that, hence my claim of 6 meters}

- Thomas

 

[biggen]

The T version has a terrible minimum focus distance. I’m glad this post is here. I need to get around to modifying mine to see if I can shorten it.

 

[bigredfish]

I checked the Empiretech data sheets:
IPC-COLOR4K-X with 2.8 mm lens has 3 m (10.2 ft) focal depth. {That is confirmed by your photos}
IPC-COLOR4K-T with 2.8 mm lens has 5 m (16.4 ft) focal depth. {Mine seems a little bit further than that, hence my claim of 6 meters}

- Thomas

Yes agreed. My point was the bullet is better

 

[Oneup]

The T version has a terrible minimum focus distance. I’m glad this post is here. I need to get around to modifying mine to see if I can shorten it.

I guess you sacrifice the long distance focus when setting the close focus better?

 

[biggen]

I guess you sacrifice the long distance focus when setting the close focus better?

Yes, but long distance doesn't matter much anyway when working with focal distances this small.

 

[EMPIRETECANDY]

Yes, this mainly because of the turret hardware limited,bullet is bigger, so the lens design the turret will be a little hard, these models have longer focus distance than normal IR cams or the full color one.
So for very nearby watching use a 2.8mm turret would be great!

 

[jeff_]

@EMPIRETECANDY, would you recommend attempting the method @Photon Farmer has explained about to adjust the minimum focus distance? I've made the mistake of purchasing a 3.6mm when I probably should have ordered a 2.8mm and made better use of the 1m closer focusing at my back door. I only really need from approx 3-6m in focus. I'm happy to carefully give manually focusing a go, but not if it's easy to break the lens.

 

[EMPIRETECANDY]

The camera 3m focus there is no problem. Here is the testing pic, that is only at 1.5m high, horizonal distance to the big box is 1.65m(5.41ft), so it has some blurry, but at 2m（6.6ft）, it will be bit clear. The focus distance not their specification shows.