Yes, I have read many positive reviews about the 5442H-ZHE VF. Sounds like a winner. I just got a IPC-Color4X-B180 and want to try it for one of my street-view cameras. Currently I am using a Color4K-X in that location (have all three versions: 2.8, 3.6, and 6mm). Plenty of light from one street light for the 4K-X, but I am thinking that the B180 might not work quite as well with that illumination. Anyway, going to try it out and see. The wide angle is appealing for an overview camera. BTW, really enjoy your thoughtful reviews. Nice work always.
Are the 5442's still best? or time for 4k variants...
- Thread starter CamCrazy
- Start date
As you put words into my mouth I never said and are repeatedly resorting to an "argumentum ad hominem", there is no point in discussing this with you further.
Last edited:
fenderman
Staff member
- Mar 9, 2014
- 36,892
- 21,408
That is precisely what you said . It's okay to admit that you don't know what you're talking about and that you're wrong... Stop posting misinformation. You literally have not seen or tested any of these 4K cameras with one over 1/1.2 sensors with or without F=1.0. You are a surveillance camera novice. So much so that to prove your point about the alleged focus difficulties you link to a post about need 3-year-old dual lens camera that has a focus problem which is not related in any way to the issue you were discussing.
Last edited:
As I said before:
As you put words into my mouth I never said and are repeatedly resorting to an "argumentum ad hominem", there is no point in discussing this with you further.
At the risk of venturing into turbulent waters, back in the days of newspapers, the reporters had a saying "F8 and Great" meaning set the camera's f-stop on 8 , and everything will be in focus. All you worried about was getting enough light for proper exposure.
Like news photography, security photography isn't interested in bokeh (artistically blurred background.) We want foreground, background and everything in between to be in focus. Lower f-stops (i.e. wider apertures) bring more light onto the sensor, but there is a tradeoff. The area in front of the lens that is in focus is very narrow by the time f-stop approaches zero. The size of the sensor also plays into it. Smaller sensors like cell phone cameras have wider focus range than large-sensor photo cameras.
So as sensors on security camera sensors get bigger, the attempt to get better night vision with lower f-stops means depth of field (the range where the camera's in focus) will be more of an issue. I wouldn't be surprised to see security cameras having autofocus in the future.
Like news photography, security photography isn't interested in bokeh (artistically blurred background.) We want foreground, background and everything in between to be in focus. Lower f-stops (i.e. wider apertures) bring more light onto the sensor, but there is a tradeoff. The area in front of the lens that is in focus is very narrow by the time f-stop approaches zero. The size of the sensor also plays into it. Smaller sensors like cell phone cameras have wider focus range than large-sensor photo cameras.
So as sensors on security camera sensors get bigger, the attempt to get better night vision with lower f-stops means depth of field (the range where the camera's in focus) will be more of an issue. I wouldn't be surprised to see security cameras having autofocus in the future.
bigredfish
Known around here
fenderman
Staff member
- Mar 9, 2014
- 36,892
- 21,408
I don't understand why you feel the need to lie.... Those were your exact words... You made a false statement about 1/1.2 sensors being more difficult to focus but moreover, even if true you fail to account what steps manufacturers will take to deal with the same...
Incompetent newbies who have never used surveillance cameras before like you should not be pushing your assumptions about specific setups that you've never tested and you've never even seen anyone else test... Why don't you pull up some images taken from the cameras we've discussed..
As a newbie, our primary goal is to learn. It may be more productive not to talk down on people.
You know, I always think about this when I see the term varifocal being used as a synonym for zoom. As I remember it, a varifocal lens is one which keeps a steady focus as it zooms in and out. This requires some extra engineering by the lens manufacturer. It would be important for a ptz to be varifocal, but not so much for a camera you're just going to zoom to get the desired field of view and then leave alone. All the zoom lenses I ever had would also change their maximum f-stop, with the wide end being lower (more light coming in, but harder to focus) and the tight end being significantly higher.
Same here, but constant aperture zoom lenses do exist. They are usually more expensive and weigh more. (front lens is larger)
I go back to the days when the varifocal zoom lenses were manual-focus only. They were made for news-gathering and got picked up by reality tv and even scripted shows to some extent. The operator had to set the focus manually, but once it was dialed in, the lens would stay focused through the range of its zoom. This commanded a hefty premium, and you didn't see varifocal lenses on consumer cameras.
I'm sure that in these days of good electronic autofocus, it would be a lot cheaper to use electronics to hold focus, so what you say doesn't surprise me.
I'm sure that in these days of good electronic autofocus, it would be a lot cheaper to use electronics to hold focus, so what you say doesn't surprise me.
CCTVCam
Known around here
- Sep 25, 2017
- 2,834
- 3,712
I don't think it's factory focusing but Depth of Field you're observing. Put a large sensor on a wide aperture and you get a very shallow focus range.
I have 2 x 4kx and the dof is indeed shallow.
I'd predict that the 5442 on a 1/1.2" and f1.0 will have a similar dof to a 4kx, simply because it's a similar sized sensor on the same aperture. However, I don't have one so until someone has tested it.....
The real answer here is manufacturers are going to have to balance sensor size vs aperture to give the best low light performance whilst not getting too shallow on dof. eg I mentioned it elsewhere - I believe one of the action cameras on a 1" sensor uses an f3.6 lens. I rather suspect the CCTV manufacturers are just discovering large lens + f1.0 isn' a good idea and that they need to look to other combinations either at the sacrifice of a little low light performance, or at the cost of an even bigger sensor but on a smaller aperture to rebalance the dof vs light gathering ability. The best low light camera seen on here had a 35mm sensor, but unfortunately it was north of £5k without a lens and Dahua discontinued it, presumably because of low sales. However, whilst larger sensors are the way to go, combining them with large apertures isn't. The 35mm sensor used an DSLR camera lens so in most instances would have had an aperture north of f5.6 with any kind of zoom.
Agree, I observed this from 6x9 photography and large scale darkroom work in the past. This is one part of the F=1.0 problems. But it is already worked into the specs. All these cameras list DOFs starting further away than their F=1.6 relatives. Some people ignore this until it hits them. That is a user problem.
My three 5442 f=1.0 lenses tell me a different strory.
The 3.6mm is supposed to have DOF starting at 2.6m. But it is still noticably blurred at 4m. It is even somewhat blurred at 9m. So this is not me looking at something outside the stated DOF, this is the camera not being crisp inside the stated DOF. Both 2.8mm lenses provide a clearer image at 4.0m, despite lesser magnification.
Why is it slightly blurred? It may not be focused, which is another way of saying the object isn't located in the actual DOF. Or it may have a bad lens assembly. Or there may be some problem with the sensor. So let us take a look at the other lenses.
My two 2.8mm 5442 F=1.0 lenses tell a different part of the story. They are crisp in some distance zone. But it isn't the same distance zone for these two. Despite them being the same model, same settings. One lives up pretty much to specs, DOF starts at about 1.6m. At 1m, it is noticably blurry (which is quite OK, specs warned you). The other 2.8mm lens seems slightly blurry at the far end but renders well to about 1m. So in these two "identical cameras" the lens or focus has been adjusted differently. As these are just two samples, it gives you an estimate about the variability of factory focus adjustment.
If you take the angular turn difference between the 2.8mm lenses, take it to a 3.6mm lens and apply this angular turn it in the other direction, you would likely get a rather far off DOF. Maybe even beyond infinity. Which would bring us back to the 3,6mm lens. If you have ever used a manual focus camera lens, you will have observed that you have to turn the dial a lot for near distance changes. But it isn't such a big turn from 2.6m to infinity.
My first task will be to find out if my 3.6mm can render a crisp image with some help outside. Cause I would like to rule out the sensor as cause.
Edit:
I am not sure I understand your statement. To me it sounds as if you would like to take one of my 5442 f=1.0 lenses and just enlarge the sensor. Afaik, this would change nothing in the already existing region of the sensor. So the DOF would stay the same there. But perhaps this current lens would not illuminate the entire new sensor field or have severe distortion further out.
Last edited:
CCTVCam
Known around here
- Sep 25, 2017
- 2,834
- 3,712
The 5442 is on a 1/1.8" sensor. Smaller sensor = larger DOF even with the same aperture.
How do you tell which fixed lens focal length you're closest to once you find the right zoom on the varifocal?
When I hover the cursor over the zoom slider I just see a value between 0 - 2275 but I'm not sure what these correlate to.
