bigredfish
Known around here
New: These look interesting - HDW3449H-AS-PV-PRO
- Thread starter bigredfish
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Yes they have. I wish they’d put the deterrent lights on this dual lens model.
https://us.dahuasecurity.com/?product=4mp-night-color-2-0-fusion-network-eyeball
EMPIRETECANDY
IPCT Vendor
Cool, will get some to play. I watched hikvision's not too sharp compare to the pure full color camera or the pure IR one.
Looks interesting but wish it was a varifocal out to 12mm.
steve1225
Getting comfortable
There are a new models with 4mpx, 6mpx and 8mpx... All 1/1.8".. And all with WDR only at 120db... Very limited IVS functions... and missing some AI modes (VideoMetaData, Face*, People count etc).. Plus hybrid (IR + warm) light and sound/light alarm..
So this is copy/Dahua reply to last generation of hybrid HikVision ColorVu 2xxx series cameras which have the same specs..
Those cam use the same sensors as latest HikVision ColorVu 2xxx series...
Those are NOT 1/1.8" 4/8 MPx sensors from OmniVision (as Dahua 5xxx and 7xxx)!!!
4MPx OmniVision have WDR 140db.. and OmniVision don't have 6MPx 1/1.8" sensor...
Yeah, this is probably to offer a balance of costs vs features using lesser quality specifications.
There are a new models with 4mpx, 6mpx and 8mpx... All 1/1.8".. And all with WDR only at 120db... Very limited IVS functions... and missing some AI modes (VideoMetaData, Face*, People count etc).. Plus hybrid (IR + warm) light and sound/light alarm..
So this is copy/Dahua reply to last generation of hybrid HikVision ColorVu 2xxx series cameras which have the same specs..
Those cam use the same sensors as latest HikVision ColorVu 2xxx series...
Those are NOT 1/1.8" 4/8 MPx sensors from OmniVision (as Dahua 5xxx and 7xxx)!!!
4MPx OmniVision have WDR 140db.. and OmniVision don't have 6MPx 1/1.8" sensor...
Both companies seem to be doing the same in this area to capture the lowest hanging fruit customers to the highest end with real performance and features.
Probably the worst scam from Hikvision was offering human / vehicle detection with zero adjustment on the entry level models.
EMPIRETECANDY
IPCT Vendor
Yes, need a cheap model for fighting with hikvision, l will get some to play soon and will see how is going.
There are a new models with 4mpx, 6mpx and 8mpx... All 1/1.8".. And all with WDR only at 120db... Very limited IVS functions... and missing some AI modes (VideoMetaData, Face*, People count etc).. Plus hybrid (IR + warm) light and sound/light alarm..
So this is copy/Dahua reply to last generation of hybrid HikVision ColorVu 2xxx series cameras which have the same specs..
Those cam use the same sensors as latest HikVision ColorVu 2xxx series...
Those are NOT 1/1.8" 4/8 MPx sensors from OmniVision (as Dahua 5xxx and 7xxx)!!!
4MPx OmniVision have WDR 140db.. and OmniVision don't have 6MPx 1/1.8" sensor...
Those cameras never reached the market where I am, would have loved to get one of these. Im not to pushed on the deterrent lights. The new Tioc is still a 3 series so you dont get all the IVS functions as you would on that one.
They will have Acupick though which some in here are interested in I feel
EMPIRETECANDY
IPCT Vendor
Booked some, will have at Middle June.
alekk
Pulling my weight
Note specs says F/1.0 lens ... easier to do if fixed focal length.
It's a logical response to Hikvision.
I'm holding out for the varifocal F/1.0 lens with 1/1.2" (latest technology) sensor - aka the "light sucking monster" ;-)
It's a logical response to Hikvision.
I'm holding out for the varifocal F/1.0 lens with 1/1.2" (latest technology) sensor - aka the "light sucking monster" ;-)
CCTVCam
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With that Alekk you'll have no depth of field. That's been something some don't like with the 4kt and the cause is most probably the aperture size. The larger the sensor, the shallower the dof. Add in a wide aperture and you get a very shallow area thats in focus. Larger sensors are great but they probably need to be paired with a narrower aperture like a 1.6 which reduces the overall amount of light gained.
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alekk
Pulling my weight
Roger on the reduced DOF @CCTVCam ... and I certainly do NOT expect a sharp image from a foot away to infinity when zoomed in with large sensor/aperture since that ... violates the laws of optics! ;-)
But if you are on the wide-end of the focal length, do you think reasonable focus/sharpness is attainable from ~10/20' to infinity?
I have seen the complaints about lack of sharpness on the larger sensor/aperture camera's, but don't have first-hand experience with them. Is perhaps a contributing factor that the large sensor/aperture are more demanding of the lens, etc.?
Perhaps related is when/as (regular) cameras got more mega-pixels, us pixel-peepers would zoom in a 100% and see defects (and the laws of optics) more easily ... which begat grumbling ... which somewhat subsided when newer technology lens came out with better optics.
But if you are on the wide-end of the focal length, do you think reasonable focus/sharpness is attainable from ~10/20' to infinity?
I have seen the complaints about lack of sharpness on the larger sensor/aperture camera's, but don't have first-hand experience with them. Is perhaps a contributing factor that the large sensor/aperture are more demanding of the lens, etc.?
Perhaps related is when/as (regular) cameras got more mega-pixels, us pixel-peepers would zoom in a 100% and see defects (and the laws of optics) more easily ... which begat grumbling ... which somewhat subsided when newer technology lens came out with better optics.
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bigredfish
Known around here
While DOF is an issue on the 4KT, I’ve not seen that at all on 4MP 5442s with the 1/1.8 sensor and I’ve installed a lot of them.
alekk
Pulling my weight
Good info from an extremely knowledgeable source - thanks @bigredfish. Some random thoughts below.
Depth of field doesn’t immediately change from clear to blurry - there's a "circle of confusion" and it depends on how visually discriminating you are. So I'm wondering if since you have "not seen at all" on the 5442's with 1/1.8" sensor and F/1.8 lens, how noticeably different (using same focal length/distance) would that reduction in DOF be with a 1/1.2" sensor and using SAME F/1.8 aperture? And then how much does it change as you open it all the way up to F/1.0 ... which also demands more from the lens.
In the "regular" camera world, you can open up that aperture and with a big telephoto lens, the drop in DOF is very obvious and often desirable to isolate the subject. But not near as much with wide-angle, especially if you aren't trying to nail focus on something really close up. Sure, if you want those wildflowers as a foreground element, you have to close the lens back up (or focus stack) ... but then defraction comes into play ... really soon on high-mega-pixel cameras.
So I played around with some DOF Calculators - here's a pretty nifty one that also does a visual simulation.
For my specific application, the field of view is about a focal length of 28mm (35mm equivalent) and my area of interest is from 5-30 meters. So I set the focus point at 8 meters and I got the following numbers for the depth of field.
Even a 1" sensor (1/1.2" wasn't an option, but obviously would have more DOF) works (barely) for my parameters - obviously if you add telephoto and/or increase the near distance requirement (or are more visually discriminating), your mileage may vary. I also include the DOF distances when you set the focus at the HyperFocal (HF) distance. Note all distances are in Meters.
For a 1/1.8" sensor with 5.8mm lens focused at 8 meters
F/1.8 has DOF of 2.23-Infinity with HF@ 3.10 so focus from 1.55+
F/1.0 has DOF of 4.39-Infinity with HF@3.29 so focus from 2.07+
For a 1/1" sensor with 10.2mm lens focused at 8 meters
F/1.8 has DOF of 3.22-Infinity with HF@5.39 so focus from 2.7+
F/1.4 has a DOF of 3.72-Infinity with HF@6.93 so focus from 3.47+
F/1.2 has a DOF of 4.02-Infinity with HF@8.08 so focus from 4.04+
F/1.0 has DOF of 4.39-45.34 with HF@9.70 so focus from 4.85+
BTW, just to show how much difference zoom makes, if I set that 1" sensor to 18.3mm (which is a 35mm equivelent of 50mm), the DOF (at a focus point of 8m) is now only 6.37-10.75 meters.
So for my application of 28mm (35mm equivelent) field of view and area of interest from 5-30 meters, even with a 1" sensor and an F1/.0 lens, I could set the focus point at 9.7 meters and have "reasonable" sharp focus from 4.85 meters to Infinite. I could get a little "closer" by setting the focus at 7 meters so my DOF would be from 4-25 meters. Regardless, I would probably grumble about the sharpness at the near and far points! ;-)
So while it seems that the not-too-challenging situation of 28mm FOV with focus from 5-30 meters is doable with a 1/1.2" sensor and F/1.0 lens, it does approach the the optical limits.
Disclaimer: This is all theoretical based on laws of optics and assumptions above. Does not account for cumulative errors due to lens/sensor/image processing, etc. Plus I do NOT have hands-on experiences with the latest generation of 1/1.2" sensor and F/1.0 cameras.
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bigredfish
Known around here
LOL you obviously know far more than I on the subject. I think I follow most of it and I’m sure you’re right about it being present. I’m speaking from the practical side in that it’s noticeable on the 1/1.2” 4K-T but not so much on the 1/1.8 5442s within our normal residential scenes and distances.
I tend to use fixed lens where possible so that may be part of it. I do notice it slightly with zoom, especially with high zoom PTZs it becomes more observable but not really on the std 2.8-12mm cams.
I tend to use fixed lens where possible so that may be part of it. I do notice it slightly with zoom, especially with high zoom PTZs it becomes more observable but not really on the std 2.8-12mm cams.
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CCTVCam
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My experience of the 4kt is it's good camera but the dof drops off rapidly before and after the focal point. As an aside, it also suffers badly from compression away from the focal point in the background. I have to wonder here if this is something to do with the firmware. Could it be reducing the compression in these areas to save bandwidth? I know some VR gaming headsets reduce the quality away from the centre where you're focused. That said, mine aren't going anywhere anytime soon. They're still good cameras overall within the limitations of not being great too far behind or to a lesser effect in front of the focal point. I wouldn't use one for LPR though!
@bigredfish - the smaller sensor on the 5442's will explian why the dof is greater. I think on the 4kt, they chose an aperture a bit too wide for the sensor size.
@bigredfish - the smaller sensor on the 5442's will explian why the dof is greater. I think on the 4kt, they chose an aperture a bit too wide for the sensor size.
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