I’d like to ask about this Night Vision Camera please:
Are you able to keep it in a closed, air-tight, waterproof polycarbonate container (with an RPi)? I know it gets quite hot, so wasn’t sure if I need some ventilation or a fan etc.
If you’re only taking photos every few hours, is there a way to turn off the camera so it doesn’t get too hot? I note that when it’s not in use, the photoresistors (or something else) seems to still be glowing and giving off heat.
If I do have it in a waterproof container with a clear lid, would I need to somehow position both the infrareds and lens against the clear lid to avoid any reflection and to best ensure the photoresistors work effectively, or is it okay just to have the lens against the clear lid?
Finally, I don’t see any mount on the camera board, so how are you suppose to position it securely?
Thanks so much,
Whether or not the night vision camera will see out of your waterproof container will depend a lot on what material it is made of and how thick it is. Just because something is transparent to visible light doesn’t mean it’s transparent in the infrared spectrum that the night vision camera relies on heavily.
This guide covers what materials can be seen through and shows some examples.
Veritasium also did a great video explaining how things can look very different in the ultraviolet spectrum which sits on the other side of visible light which you may find interesting.
Regarding the thermal situation and how your project will avoid overheating, the first step I’d take would be to tally up the power consumption of each device as a ball-park estimate.
The IR LEDs on the camera are 3 Watts each, the camera is likely to be negligible compared to that. A Pi 4B’s typical bare board consumption with no accessories is 3.06 Watts for a comparison point.
There are so many factors that impact the heat dissipation of a sealed container which include the material, surface area, surface finish, and ambient temperature so I can’t really estimate that. You’ll likely get the most useful information from real-world experimentation. If you set up your container with a resistor and a thermometer inside it, you’ll be able to judge how hot it gets inside for a given power level pretty quickly.
It seems since the camera module is powered directly from the CSI connector that it will be powered on whenever the camera is in use.
I’d need to read a bit more to determine if it’s powered on whenever it is enabled in the rasi-config, or just when it’s being accessed and it powers down when the Pi isn’t accessing the camera.
I think you can still get them. When I was working we used a stick on label which changed colour permanently when a pre defined temperature is reached. By using a range of different temperature labels stuck inside or on a piece of equipment the user could get a fairly accurate idea of the maximum temperature reached over a period. Similar to the tell tale moisture detector labels found inside mobile phones etc. Used I assume to tell if a device has been dunked in water or something to get out of a warranty claim.
This method saves all the hassle of setting up temperature monitors and recording devices. The down side is that you don’t have any idea at what time a particular temperature was reached only the fact that it happened. In most cases the time doesn’t really matter, only the fact that that temperature was reached.
I don’t remember where these came from but I will do some research and try to find out. Element 14 would be a good place to start as they were used extensively (Farnell in those days) when bits were required quickly in small quantities for development work.
Search “Thermindex” and you will find strips covering different ranges. Thermindex is one manufacturer but there are others. Element 14 stock this brand.
Thanks so much @Trent5487676 and @Robert93820. I will run some tests to see if it will ‘see through’ my clear lid. I didn’t even suspect that that was going to be an issue, so thanks for the heads up. I found a design for a 3D printable camera enclosure that exposes just the lens, so I’ll also take a play with that.