Thank, I would also prefer teflon over glue. Do you have an online source, or the spec of the longer screws please?
Change a Hikvision lens from 2.8mm to 4mm or 6mm?
- Thread starter sharpharp
- Start date
Thank, I would also prefer teflon over glue. Do you have an online source, or the spec of the longer screws please?
Thanks again, and sorry for the continued dumb question, but I have one more.
The longer screws are for the lens board, and you put washers under the board, is that correct.
is 2 x 10 a standard size for most cameras?
bickford
Getting comfortable
- Mar 12, 2016
- 468
- 432
DS-2CD2342WD-I 4MP originally 2.8mm.
Lens shots purely to show difference in FOV- all taken through a very dirty window which is why they all don't look too good. Each of them has only been roughly focused and I was holding the disassembled camera by hand.
Original 2.8mm lens
6mm
8mm
12mm
Lens shots purely to show difference in FOV- all taken through a very dirty window which is why they all don't look too good. Each of them has only been roughly focused and I was holding the disassembled camera by hand.
Original 2.8mm lens
6mm
8mm
12mm
bickford
Getting comfortable
- Mar 12, 2016
- 468
- 432
This week i have converted a DS-2CD2342WD-I : http://www.hikvision.com/us/Products_1_10508_i7593.html with a 25mm lens from eBay its running pretty good as ou can see :
distance beetween camera and licence plates is about 25 meters.
The only problem I have is that at night the vehicles appear with squares or strange shapes around them, the angle of my camera is not good I know it but it is strange.
BICK
distance beetween camera and licence plates is about 25 meters.
The only problem I have is that at night the vehicles appear with squares or strange shapes around them, the angle of my camera is not good I know it but it is strange.
BICK
@bickford which 25mm lens did you use and did it require spacing the lens module back?
I did some more examples with the lens changes, so I've compiled them below. From 2.8mm (stock lens), 4mm (stock lens), 6mm, 8mm, 12mm and 16mm on the same model DS-2CD2342WD-I 4MP camera. Taken through a dirty window and hand held, so they're not representative of the image quality you'll obtain, only the FOV. The 16mm had been focused for closer subjects, so the house across the road isn't in focus. All the lenses I tried are more than capable of matching the clarity and detail of the OEM lenses.
(Note: Experimenting with the "longer" length lenses quickly shows up the advantages of having a varifocal at that range which has continuous electronic focus. The depth of field is very restrictive: the focus for close range subjects is very poor if set the focus of the lens on distant subjects. You really need to manually focus the lens for the subject range where that camera will be used.)
POSTED FOR FOV COMPARISON ONLY- the focus isn't perfect in some shots and all are taken hand held through a dusty/dirty glass window!
2.8mm stock lens
4mm stock lens
6mm after-market "5MP IR" lens
8mm after-market "5MP IR" lens
12mm after-market "5MP IR" lens
16mm after-market "5MP IR" lens (out of focus on house, has been focused for closer use- note the bushes in foreground in focus.)
PS: I found using my NVR's digital magnification (zoomed in) using Liveview to be an excellent way to focus the lenses.
I did some more examples with the lens changes, so I've compiled them below. From 2.8mm (stock lens), 4mm (stock lens), 6mm, 8mm, 12mm and 16mm on the same model DS-2CD2342WD-I 4MP camera. Taken through a dirty window and hand held, so they're not representative of the image quality you'll obtain, only the FOV. The 16mm had been focused for closer subjects, so the house across the road isn't in focus. All the lenses I tried are more than capable of matching the clarity and detail of the OEM lenses.
(Note: Experimenting with the "longer" length lenses quickly shows up the advantages of having a varifocal at that range which has continuous electronic focus. The depth of field is very restrictive: the focus for close range subjects is very poor if set the focus of the lens on distant subjects. You really need to manually focus the lens for the subject range where that camera will be used.)
POSTED FOR FOV COMPARISON ONLY- the focus isn't perfect in some shots and all are taken hand held through a dusty/dirty glass window!
2.8mm stock lens
4mm stock lens
6mm after-market "5MP IR" lens
8mm after-market "5MP IR" lens
12mm after-market "5MP IR" lens
16mm after-market "5MP IR" lens (out of focus on house, has been focused for closer use- note the bushes in foreground in focus.)
PS: I found using my NVR's digital magnification (zoomed in) using Liveview to be an excellent way to focus the lenses.
Continuing this thread.
I've fitted a "Starlight" 6mm f1.5 lens to a Hik 4MP DS-2CD2342WD-I. The stock lens fitted is f2.0 and some research seems to show an f1.4 lens allows twice the light to the sensor compared to an f2.0.... So an f1.5 should be in that ball park.
There seem to be two main sellers on AliExpress- one selling a (plastic) lens with IR filter assembly, the other bare metal lenses. I opted for the plastic lens as it looked the same design as fitted to my Hik ultra low light DS-2CD2335FWD-I camera. I've also ordered a 4mm and 6mm metal lens from the other supplier.
I've mounted the camera outside however I've got the focus slightly out
. I'm going to leave it "as is" for now as I'm mainly interested in performance changes in low light. The lens is rated as a 3MP so it might not give the same detail/ clarity as the stock lens. (When it's focused correctly, I can't comment on that aspect at the moment!)
I'll post some comparisons later when it's dark.
Edit- That was a big fail. IR reflection off my house eaves caused a near total "white out" with the 6mm f1.5 . I'd been using a 4mm lens previously and had the camera aimed at a slightly different angle, which was working okay.
I've fitted a "Starlight" 6mm f1.5 lens to a Hik 4MP DS-2CD2342WD-I. The stock lens fitted is f2.0 and some research seems to show an f1.4 lens allows twice the light to the sensor compared to an f2.0.... So an f1.5 should be in that ball park.
There seem to be two main sellers on AliExpress- one selling a (plastic) lens with IR filter assembly, the other bare metal lenses. I opted for the plastic lens as it looked the same design as fitted to my Hik ultra low light DS-2CD2335FWD-I camera. I've also ordered a 4mm and 6mm metal lens from the other supplier.
I've mounted the camera outside however I've got the focus slightly out
. I'm going to leave it "as is" for now as I'm mainly interested in performance changes in low light. The lens is rated as a 3MP so it might not give the same detail/ clarity as the stock lens. (When it's focused correctly, I can't comment on that aspect at the moment!)I'll post some comparisons later when it's dark.
Edit- That was a big fail. IR reflection off my house eaves caused a near total "white out" with the 6mm f1.5 . I'd been using a 4mm lens previously and had the camera aimed at a slightly different angle, which was working okay.
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@triumph202 Can you provide AliExpress links to lens that you've had good experiences with? Especially to vendors that you think were reliable?
dfhawk
Getting the hang of it
I have ordered at least a dozen lenses from Ali and all orders were fulfilled -- as long as the lens was at least 5MP (generally I used them for 3MP cameras) I had really solid results.
I ordered from the following:
4K Productions Store
Excelax Technology
Ale YISHUN Electronic CO.,Ltd
TOPCAMCCTV CHINA Store
Yumiki Store
GWFEYE Official Store
Witrue Factory Store
Chinajoy1st CWLENS Wholesaler store
Jiangxi Hongxin Optical Co., Ltd.
MUXINVISION SECURITY CCTV
I ordered from the following:
4K Productions Store
Excelax Technology
Ale YISHUN Electronic CO.,Ltd
TOPCAMCCTV CHINA Store
Yumiki Store
GWFEYE Official Store
Witrue Factory Store
Chinajoy1st CWLENS Wholesaler store
Jiangxi Hongxin Optical Co., Ltd.
MUXINVISION SECURITY CCTV
Most of mine came from this seller fulekan Official Store - Small Orders Online Store, Hot Selling and more on Aliexpress.com | Alibaba Group
As mentioned, go for the 5MP (or greater) resolution lenses.
The Starlight lenses are from a different store, but I wouldn't bother trying them on a non Starlight camera.
@triumph202 So the Starlight lenses did not improve night vision for your DS-2CD2342WD-I? I have the same Hik turret and wanted to see if better night vision is possible without buying a new camera.
It didn't seem to make a worthwhile difference. I'm going to swap a few cameras around today, so will be able to give you a better idea after that. The Starlight lenses are all rated at 3MP resolution, so in theory you would be losing definition by fitting one onto the 4MP camera. To my eyes, the image is okay during the day- but perhaps not as sharp/ clear?
There are other benefits to updating to one of the proper low light models (like the 2335FWD-I.) You gain H265 codec, so a decrease in bitrate. I can easily max out my Hik NVR with the 4MP 2341 cameras which use H264 codec as you only get an average of 10mb/s per camera (80mb/s total over 8 channels/ cameras.) The 2335FWD-I also has smarter control over day/night modes- it appears to use the video signal to control the switching rather than the simple light sensor used on the 2342.
The stock 4MP 2342 will give better results during the day- I can notice it on my 55" 4K TV. At night the 2335FWD-I is vastly superior. (It would be interesting to try a 2342 lens on the 2335 to see if it improves the daytime clarity.)
There are other benefits to updating to one of the proper low light models (like the 2335FWD-I.) You gain H265 codec, so a decrease in bitrate. I can easily max out my Hik NVR with the 4MP 2341 cameras which use H264 codec as you only get an average of 10mb/s per camera (80mb/s total over 8 channels/ cameras.) The 2335FWD-I also has smarter control over day/night modes- it appears to use the video signal to control the switching rather than the simple light sensor used on the 2342.
The stock 4MP 2342 will give better results during the day- I can notice it on my 55" 4K TV. At night the 2335FWD-I is vastly superior. (It would be interesting to try a 2342 lens on the 2335 to see if it improves the daytime clarity.)
Sorry to bring out this old thread, but this sentence caught my attention:
"2.8mm outside is almost never useful"
Why is this? I think the 2.8mm gives you a good overview doesn't it?
"2.8mm outside is almost never useful"
Why is this? I think the 2.8mm gives you a good overview doesn't it?
alastairstevenson
Staff member
Yes, it does.
But 'a good overview' is the antithesis of 'good identification' as the wider field of view gives fewer ppf (pixels per foot) that is needed for such as facial detail.
The more I am getting into this and tweaking my setup the more I realize that what you are saying in very true and at the same time, that you almost need more than one or more than two cameras to cover the front of a property. What I have noticed that is that a 2.8 4MP or 8MP a good height (10') is great for an overall, but then you need at least 4mm looking at specific areas of interest. One again the challenge always is know where the intruder will be coming from to get a good ID.
I have a 2.8mm 4MP at my door for instance to keep tabs on packages, but since the UPS guy or anyone trying to steal it will be so close the camera it does not matter that it is a 2.8mm and I get the added benefit of getting to see a little more.
Based on all this, what I have come up with for the front of my home is to have a 2.8mm looking at the driveway (cars) and a 4mm looking at a distance towards my property line. The idea would be to identify anyone entering my driveway.
I don't want to carry on this old thread too much, but I think you'd be better served with two cameras with 6mm lenses on your driveway and a couple or three cameras with 12mm lenses on the property line, depending on how far away it is and what you want to see. You might want a single wide angle to tie them all together, but I don't think it adds much value unless your actively monitoring and providing positional updates of a suspect to authorities. Check out my driveway pics at Just Sharing My Progress. They are both varifocals with a zoom setting equivalent to a 6mm lens.