I have a Hosafe PTZ security camera, and during a recent cold snap, the focus froze or stuck. I've tried manually adjusting the focus using the software, and it appears to move only a hair in either direction (in or out) but remains out of focus. Is it possible that due to the freezing temps, any lubricant? has thickened enough that the focus mechanism can't overcome the resistance? Anybody familiar with how basic focus mechanisms work? Does the lens rotate to focus, or does it move in or out? I may attempt to poke around inside it, or otherwise wait till the temps warm up and see if it starts work properly again. The focus is sharpest at its extreme zoom point, which is still very blurry. When zoomed out, the picture is totally unviewable, if that's any help?
PTZ focus stuck
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looney2ns
IPCT Contributor
I would wait until it warms up, and NOT be messing with trying to focus until it does warm up, to prevent further possible damage.
I finally took it down and opened it up. There's 2-3 worn teeth on the focusing ring near the end of its travel so I may try to form new teeth using epoxy shaped with a knife, and give it a clean/lube, or failing that, will just replace the whole lens complete with IR filter assembly available for $35 Cdn for a 5 MP to replace the existing 2 MP. The motor rotates the barrel causing the lens to move in a linear direction in and out. Likely cold weather/age/lack of lubrication created a bit too much friction for the nylon teeth to handle.
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Assuming I'm not changing the image sensor, which I assume was designed for the original 2 MP lens, will "upgrading" to the 5 MP lens have negative effects (ie pixilation/poorer image at night). Will it improve the daytime image? I realize the existing image sensor is the key ingredient and limiting factor here, so is it just a case of wasting money upgrading the lens when a 2 MP would do the same job because the image sensor will downgrade the lens image, or will it have other detrimental effects or benefits? For a consumer-grade quality camera, it was great at capturing IR/low light images. The difference in cost between the 2 MP and 5 MP lenses was only about $2, so I figured what the heck.
Well I replaced the lens assembly on the image sensor board (which is mounted using 2 screws, and plugged in the two board connectors), and ran it through its paces, and all seems well except for focusing at its widest field FOV (shortest focal length). I tried overriding the auto-focus settings using my PC APP but it's behaving as though there's a physical limit stop preventing it from focusing any nearer. Anybody familiar with these motorized vari-focal lenses? I noticed there appears to be screws on the perimeter of the focusing ring (clearly viewable in the pic on the right above), which may adjust the limit stops for focus but I just wanted to be sure before I start messing with them. Based on their position on the ring, it would make sense that they're limiting screws, but they could also be some kind of assembly screws. I'm guessing I need about 1-2 more teeth of travel to solve the issue. The rated FOV for these lenses is 31.4 to 113 degrees of width, and everything works well from about 45 to 113 degrees, but from 31.4 to 45 degrees, I can't get a short enough focal length for a sharp image. Anybody ever had to adjust theirs?
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I used the IR cut filter that came attached to the new lens, however, I believe it's slightly taller than the original, which is throwing off the focal point. I will reinstall the new lens using the old IR filter which should solve the minor focusing issue. Although ,in theory, this higher megapixel lens should have no effect as it's limited by the original 1080p image sensor, the images seem slightly sharper both day and night. If anything, the night vision actually seems crisper, with no loss of vision using the IR illumination. Final cost including shipping was $26 Cdn, and the camera is good as new. I paid $179 Cdn 6 years ago for the entire camera, so no complaints. I also switched it over to a new POE power system which is a great feature. Luckily I ran CAT 6 ethernet when I first installed the cam. This will save me from having to use a step ladder in the garage to reset it 4-5 times a year whenever needed. The POE system will allow me to easily add a cam covering the rear yard finally, as that cam will be located 10 feet away from my pc, on the outside wall.
Surprisingly, there is very little info on the web about repairing/replacing components on security cameras. I assume a lot just get thrown out when they stop working. Hopefully somebody else can use the info in the future. The repair only required 2 screwdrivers.