DS-2CD2335FWD-I - Hikvision Ultra Low Light 3M camera

It seems to me we're kindof used to, and expect, an infinite depth of focus in these camera lenses - something we don't expect or get with a normal handheld camera.
There is presumably a design compromise between a small aperture, which gives a larger depth of focus but reduced amount of light, and a larger aperture, which gives more light but a reduced depth of focus.
So perhaps the lenses on the ULL camera have moved towards the 'maximise the light end' giving a more obvious finite depth of focus.
So in the case of your camera, you have just tweaked the setpoint out further than the factory-set compromise.

I have to say that, being familiar with how you have to compromise with a handheld camera, I've always been impressed with the depth of focus that's normally achieved with your average IP surveillance camera.

I've got a lot more knowledge of still photography and totally agree the depth of field from what's a f1.6 lens is astounding. However, I would expect they'd get infinity focus correct- they can't "guesstimate" somebody won't care the focus sucks past ~12 metres on a 6mm lens!

It's getting dark here now and the images at night are vastly improved. The Starlight isn't aimed at exactly the same point (to do direct comparisons) but what I see now is more what I expected to get from the Hik.

@aster1x I can put some photos up later. I can tell you the f1.2 lenses I was talking about are around 32mm long, the current lens is more like 17mm - so no way that will fit. There are f1.5 lenses that are the right length, but who knows how good they will be?
 
Yes, please post up the new pictures. I am also interested in how to change the lens out for better performance. In the automotive world we would call this "hot rodding". Hehehe
 
Okay, below are pictures showing the disassembly. Do so at your own risk and realise you'll be voiding your warranty. Be careful to avoid static electricity- so don't it in your polar fleece onesie while getting in and out a plastic chair!

1. Completely remove the screw and metal tab that is used to secure the turret into position. There's a circlip underneath that will need to be removed.

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2. Once they're removed the actual camera housing can be removed from the base plate by sliding it forward slightly. (The tabs in red hold it in place, along with the already removed screw and metal tab.)
You can then undo the three screws that hold the camera housing together- one of them is circled green in the below picture. Do not undo the blue screw.
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3. The camera housing can then be carefully split open. Note the rubber seal has a higher flange on one side with a corresponding higher cast into one of the housings. Remove the desiccant bag (RHS yellow arrow) and place it into a sealed plastic bag until you're ready to put the housings back together. The LHS yellow arrow points to the electrical plug that needs to be removed. There's a tab to press on the side where the arrow is pointing- press it in as you pull the plug out. Then remove the three screws circled in green.
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4. The lens circuit board should now be loose. If you can't remove it, check in the SD card slot as the card's small brown release button may be fouling - pressing it in should help.

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5. You should now have the lens module circuit board out like below. The red and black wire from the front aluminium housing are for the IR LED, unplug it off the lens circuit board. The lens itself is screwed into the sensor module and screwing it in or out is how the focus is adjusted. At the factory they have applied glue to prevent the lens moving during shipping- see blue circle. This glue will need to be carefully scraped off before you'll be able to refocus the lens. I used a small jeweller's screw driver to do it.

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Once you've removed most of the glue you should be able to rotate the lens.

6. Leave the front housing with the IR LED unplugged aside. Reconnect the plug from the rear housing circuit board to the lens module circuit board (the plug removed in step 3 with red, black, orange x2 and green x2 wires.)

7. Get a plastic bag (not a polyethylene freezer type bag as they generate static) big enough to fit the rear housing assembly inside. Cut a small hole in one of the bottom corners of the bag and feed the camera's cat 6 plug out through that hole. Place the rear half of the camera housing in the bag and close the bag around the lead that joins the two circuit boards together. I did this to avoid any chance of accidentally shorting the lens module to either the alloy housing or the circuit board in it. Sorry no pictures of that stage.

8. Plug the camera back into your network and power it up. Find something like a brick wall that is a long distance away (30m or more) and screw the lens in/ out to adjust the focus. Take your time. If you can get the display up on a large screen high res TV even better. It's safe to hold the module in your hands while it's powered up (be sure to remove any rings or other jewellery that could short out the lens circuit board.)

9. Once finished power the camera down and do the reverse of the above steps to reassemble it. Don't forget to put the desiccant bag back in and make sure the rubber seal is the right way up. You may need to carefully press in the SD card release button to get the lens circuit board back into the front housing. Make sure the lens itself is clean and the inside of the front housing glass before reassembling.

Measurements:
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The standard lens is supposed to be f1.6 .
 
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Very good write up. Thank you so much for taking the time to post this. Actually it looks fairly easy to do with your directions. Fortunately my camera seems to be focused okay. However if I wanted to change the lens this is how to do it.
 
I notice that this new generation of turrets (2335) do not have the LDR sensor that measures the light intensity that determines the auto switching between day and night profiles. It was the small 4mm hole between the lens and the EXIR. So how do they measure now the light intensity? Do they evaluate it from the sensor?
 
No worries. Hopefully it will help someone out. :)

It only looks like a relatively small focus issue in the pictures above, but it's made a big difference. Probably more noticeable at night, what previously looked like noise also involved poor image focus.

(It was actually my DS-2CD2342WD-I that was more difficult to do- it's got a mylar ribbon plug. It looks like the lenses would be a straight swap between the two.)
 
Has anyone else experienced " white flashing " on their 2335FWD-I ?

I've had the NVR alarm going off for video tampering (or similar) on one of them every night they switch to B+W + IR on. I didn't think much of it, but when I checked the first time the picture was massively over exposed- almost whited out. Then this morning, the 2nd camera set the NVR alarm off. I checked the video and it "whited out" twice in about five seconds- like the camera exposure has suddenly lost the plot?

I've since noticed other threads and videos for other Hik cameras with the same problems eg:
and White flashes on HikVision 4MP cameras
 
My cameras are not set for the alarm so I have never noticed any white flashing. The only time I would notice it is if it happened while I was sitting in front of the computer screen watching.
 
Has anyone else experienced " white flashing " on their 2335FWD-I ?

I've had the NVR alarm going off for video tampering (or similar) on one of them every night they switch to B+W + IR on. I didn't think much of it, but when I checked the first time the picture was massively over exposed- almost whited out. Then this morning, the 2nd camera set the NVR alarm off. I checked the video and it "whited out" twice in about five seconds- like the camera exposure has suddenly lost the plot?

I've since noticed other threads and videos for other Hik cameras with the same problems eg:
and White flashes on HikVision 4MP cameras

I've not noticed this either, but again not set up for video tampering alarms.
I don't sit and watch it all day, but never seen it yet.

Sent from my ONEPLUS A3003 using Tapatalk
 
It seems a firmware issue for the other models affected (from what I read.)

I'll have a look at the video for the one that alarms every night- it seems to be when it auto switches to night/ IR. (There's a gap of about 10 minutes between when the camera senses it's time to switch to night mode and when my outside automated lights come on. Once the lights come on it switches back to colour.)

Has anyone found a firmware update and been game enough to try it?
 
Okay, the one that is alarming every night is most likely my stuff up :oops: . I checked and I had it enabled for night mode at level 7 sensitivity, but I had disabled the "Smart IR" in the box below. So it was possibly turning the IR on full power and then copping the reflection back off the house eaves- thus causing the over exposed (almost white) image. I'll see what happens tonight.

I haven't heard the other one alarm again at all, so it must be a very rare occurrence. I'll have to check on the NVR to see if I can find the log for alarms. I'm guessing they're logged somewhere on it?

EDIT: This appears to be the correct firmware for updating the DS-2CD2335FDW-I -

DOWNLOAD PORTAL

There are three different versions available- all with the same date?
 
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Good news, hopefully my 6mm should be on it's way back today, nice service from Fiona on AE.
I'll test and let everyone know once it's back, but trying to find out what was done to it.
 
Yes, that's excellent service. I sent a short message to the seller I bought mine off regarding the focus issues I had with my 6mm- and I didn't even get a response! I wasn't asking for a refund/ exchange, just asking they pass on the info to someone at Hikvision regarding the focus issues.

I had the NVR alarm going off again last night just after dusk- so more investigation is required. I might just end up disabling the video tampering on that camera.
 
I'll set my Video Tampering alarm on mine this evening if you like and see if I get the same.
 
If you can that would be good. The one that is doing it switches to night mode/ IR for about 10 minutes before my outdoor lighting comes on. As soon as the lights come on it switches back to day and stops alarming. The other camera has enough street lighting that it stays in day mode. I've tried adjusting the sensitivity down and it still does it. The only other thing I'm wondering is if some IR reflection might be the problem?
 
Ok the replacement camera is arriving Tuesday, so hopefully everything will be ok with it.

Sent from my ONEPLUS A3003 using Tapatalk
 
Hi all,

Got mine Hik 2335 6mm delivered back end of last week. I told the seller that if they didn't ensure my 6mm lens was perfect, they'd have the wrath of the ipcamtalk people to answer to :)

Anyway, spent a long time up a ladder installing mine yesterday (my legs are killing me today), swapped out my old Hik 2342 2.8mm with this one.

After messing with my phone and getting the angle right etc, I can confirm the picture is perfect edge-to-edge. My only disappointment is that the 6mm chops off a bit of the driveway, but I can live with that as I am gaining a closer picture. Perhaps in future a zoomable cam like the Dahua might be best to get optimal coverage.

Anyway, I was amazed at just how good this cam is at night, at 10pm, the picture was like daylight (no street lights near) and around midnight, the picture was still good. I tried with and without WDR and there was slightly more sharpness with WDR turned off, but not much else helped in the settings.

The daytime picture is superb, I can honestly say it's on par with my old 4MP Hik 2342, I didn't get any softness and everything is as sharp as a razor.

Can anyone suggest the best settings to use for day/night? I haven't bothered with an external IR illuminator, just using the camera for now, so if anyone can suggest better settings, do post.

It was easier configured and picked up by my HIK NVR, just a shame my NVR doesn't support H.265+. The one thing I found was that the timezones were out on both the NVR and CAM. When I saved the settings on the 2335 for the correct time, then changed a different setting like picture, the timezone changed as well.... don't know why, but the only way it would save the correct time was to manually sync with computer and then save.

One thing I need some advice on (and it's been doing my head in since owning 4+ HIK cameras) is getting the live picture on a iPhone to work.
I am using IP Cam Viewer and it connects via "Generic RTSP over TCP" but the picture hangs after 10 secs everytime. I have to reload the app to view the cam again, then yet again it hangs after 10 seconds.

Which mobile app should I use and which is the best settings / ports / to view smooth live coverage on the iPhone without it breaking up every 10 seconds via a 4G connection?

Thanks all and if you had any doubt, don't. The Hik 2335 is truly amazing.