Post by Dragon Man on Jun 14, 2014 11:22:54 GMT
As we all know, CCD chips get hot, causing hot pixels and noise.
We attempt to control this by cooling the imaging chip in the camera.
Here is my own version of how I cooled my SCC-A2333 (also the SCB-4000).
A similar process can be used on almost any CCTV camera.
I knew it was dangerous to cool the chip directly by placing a peltier cooler directly onto the chip, or even the back of the PCB that the chip is attached to, so the trick was to get the whole camera cool enough to make the chip colder without damage from Cold shock, excessive cold, or condensation.
I followed other peoples examples of placing the camera inside an Aluminum box and chilling the box. Then having a fan inside the box blowing the chilled air towards the chip.
Here's how I did mine:
1. I made an RF/Heat barrier doubling as a cold finger inside the camera. This way it blocks RF interference and heat from the lower and rear PCB's.
The cold finger attaches to the camera case at top so cold can conduct through the aluminum.
Then I placed a 5 volt micro-fan from an old Netbook onto it. I used the 12v power inside the camera to run this Micro-fan through a 5 volt 'voltage regulator' mounted near the back (to keep the extra heat away from the front).
This fan blows the cold off the Aluminium cold-finger onto the back of the chip.
__________________________
Step 2:
Getting the Coldfinger cold is done by making the whole body of the camera cold using the Aluminum box idea.
I started with 2 pieces of Aluminum Channel made for a shower recess, cut to the length of the camera body.
With one upside down to the other they interlock to make a complete wrap-around casing with small voids each side for electrics to tuck into.
You can see in the pics where I mounted the power sockets for the peltier and the Heatsink fan (I kept these as seperate power lines as the peltier cuts off at 3c degrees but I want the fan to keep running).
The Parasite box for my remote control on the other side.
When all assembled it is a perfect fit around the body of the camera.
Note: I slightly bent a curved shape in the straight sides so they matched the curve of the camera sides. More contact means more effective cooling.
__________________________
Step 3:
Then I attached the Peltier cooler out of a $29 Car Fridge.
I didn't use the enormous fan or heatsink that came with the fridge. I grabbed a smaller heatsink and fan from a dead Computer in my shed.
I attached the Heatsink using 2 small blocks of wood (poor conducter) so no heat travelled back from the heatsink to the cooled side.
I ran 12 volts into the peltier to make sure all was working good. Once I was happy that it was very very cold, I covered all the external Aluminum surfaces in sticky-backed Flocking Felt as an Insulator.
Now with the peltier running and the Camera very cold, I can't feel any cold on the outside felt, letting me know that all the cold is going inside, not off into the outside air.
__________________________
Step 4:
The switch.
I used the switchgear that came with the Peltier. It has a Hot or Cold selection but I doubt I will ever need the hot unless I want to thaw the ice off the camera at the end of a session
I mounted the whole switch assembly into a project box and mounted it to the Scopes accessory plate along with my heater control box and laser.
Here you can see it all completely wired up and in use. I took this pic whilst testing it.
Well, that's it until I show you the test results.
Was this cooling Project worth all the work?
__________________________
TWO FURTHER MODIFICATIONS TO THE PROJECT
1. I have totally removed the camera's original case, and just use the wrap-around Aluminum cover (shown in my tutorial above) as the case.
This will allow ALL the coldness into the camera, not have it trying to work its way through the steel Samsung case.
2. I have added a 40mm PC fan through the side of the case. It collects the chilled air at the peltier and blows it directly across the electronics inside the camera.
If you look at the above images you'll see where the power sockets are mounted in a void area between the Peltier and the camera body.
This area is full of chilled air. This is the air the fan will blow into the inside.
I have tested it on the work bench and the inside of the camera now gets even colder.
So now the peltier is not only chilling the Aluminum body it is also supplying the chilled air being blown inside. Which also helps chill the RF/Heat coldfinger even further for the other micro-fan to blow colder air onto the back of the chip.
__________________________
Some photos of the new Alterations:
1. The 40mm Fan mounted inside the Aluminum case
(yeah I know, the hole is cut a bit rough)
2. top view showing how much of a tight squeeze it is to get the 40mm fan in there!
3. How it all goes together without the original Samsung case.
The bottom photo shows the semi-closed-in area where the fan sucks air from the peltier cooled area (the void in behind the power sockets)
4. Close-up of what's been added inside
The coldfinger and the Voltage Regulator have contact with the Aluminum case and have Thermal Compound on them for good temp transfer.
The idea is that the cold from the case will transfer down the cold-finger to the little micro-fan and blow cold air into the back of the chip
Here is the Camera in use:
From a different angle:
____________________________
The results of the Cooling Mod.
The image is a dark frame with Gain turned up to Maximum, and at x512 sensup.
Camera had been on for 30 minutes in this image. No Hot Pixels!
___________________________
One of the great benefits of Cooling is being able to take the Gain to very high levels to capture objects in a shorter time without fear of Noise being introduced from the high gain level.
Here is a Screen Grab of Centaurus 'A' Galaxy at the crazy short time of only x96 sensup with Gain at max!
The image is very clean.
Thanks for reading this lengthy thread about my Cooling Project
We attempt to control this by cooling the imaging chip in the camera.
Here is my own version of how I cooled my SCC-A2333 (also the SCB-4000).
A similar process can be used on almost any CCTV camera.
I knew it was dangerous to cool the chip directly by placing a peltier cooler directly onto the chip, or even the back of the PCB that the chip is attached to, so the trick was to get the whole camera cool enough to make the chip colder without damage from Cold shock, excessive cold, or condensation.
I followed other peoples examples of placing the camera inside an Aluminum box and chilling the box. Then having a fan inside the box blowing the chilled air towards the chip.
Here's how I did mine:
1. I made an RF/Heat barrier doubling as a cold finger inside the camera. This way it blocks RF interference and heat from the lower and rear PCB's.
The cold finger attaches to the camera case at top so cold can conduct through the aluminum.
Then I placed a 5 volt micro-fan from an old Netbook onto it. I used the 12v power inside the camera to run this Micro-fan through a 5 volt 'voltage regulator' mounted near the back (to keep the extra heat away from the front).
This fan blows the cold off the Aluminium cold-finger onto the back of the chip.
__________________________
Step 2:
Getting the Coldfinger cold is done by making the whole body of the camera cold using the Aluminum box idea.
I started with 2 pieces of Aluminum Channel made for a shower recess, cut to the length of the camera body.
With one upside down to the other they interlock to make a complete wrap-around casing with small voids each side for electrics to tuck into.
You can see in the pics where I mounted the power sockets for the peltier and the Heatsink fan (I kept these as seperate power lines as the peltier cuts off at 3c degrees but I want the fan to keep running).
The Parasite box for my remote control on the other side.
When all assembled it is a perfect fit around the body of the camera.
Note: I slightly bent a curved shape in the straight sides so they matched the curve of the camera sides. More contact means more effective cooling.
__________________________
Step 3:
Then I attached the Peltier cooler out of a $29 Car Fridge.
I didn't use the enormous fan or heatsink that came with the fridge. I grabbed a smaller heatsink and fan from a dead Computer in my shed.
I attached the Heatsink using 2 small blocks of wood (poor conducter) so no heat travelled back from the heatsink to the cooled side.
I ran 12 volts into the peltier to make sure all was working good. Once I was happy that it was very very cold, I covered all the external Aluminum surfaces in sticky-backed Flocking Felt as an Insulator.
Now with the peltier running and the Camera very cold, I can't feel any cold on the outside felt, letting me know that all the cold is going inside, not off into the outside air.
__________________________
Step 4:
The switch.
I used the switchgear that came with the Peltier. It has a Hot or Cold selection but I doubt I will ever need the hot unless I want to thaw the ice off the camera at the end of a session
I mounted the whole switch assembly into a project box and mounted it to the Scopes accessory plate along with my heater control box and laser.
Here you can see it all completely wired up and in use. I took this pic whilst testing it.
Well, that's it until I show you the test results.
Was this cooling Project worth all the work?
__________________________
TWO FURTHER MODIFICATIONS TO THE PROJECT
1. I have totally removed the camera's original case, and just use the wrap-around Aluminum cover (shown in my tutorial above) as the case.
This will allow ALL the coldness into the camera, not have it trying to work its way through the steel Samsung case.
2. I have added a 40mm PC fan through the side of the case. It collects the chilled air at the peltier and blows it directly across the electronics inside the camera.
If you look at the above images you'll see where the power sockets are mounted in a void area between the Peltier and the camera body.
This area is full of chilled air. This is the air the fan will blow into the inside.
I have tested it on the work bench and the inside of the camera now gets even colder.
So now the peltier is not only chilling the Aluminum body it is also supplying the chilled air being blown inside. Which also helps chill the RF/Heat coldfinger even further for the other micro-fan to blow colder air onto the back of the chip.
__________________________
Some photos of the new Alterations:
1. The 40mm Fan mounted inside the Aluminum case
(yeah I know, the hole is cut a bit rough)
2. top view showing how much of a tight squeeze it is to get the 40mm fan in there!
3. How it all goes together without the original Samsung case.
The bottom photo shows the semi-closed-in area where the fan sucks air from the peltier cooled area (the void in behind the power sockets)
4. Close-up of what's been added inside
The coldfinger and the Voltage Regulator have contact with the Aluminum case and have Thermal Compound on them for good temp transfer.
The idea is that the cold from the case will transfer down the cold-finger to the little micro-fan and blow cold air into the back of the chip
Here is the Camera in use:
From a different angle:
____________________________
The results of the Cooling Mod.
The image is a dark frame with Gain turned up to Maximum, and at x512 sensup.
Camera had been on for 30 minutes in this image. No Hot Pixels!
___________________________
One of the great benefits of Cooling is being able to take the Gain to very high levels to capture objects in a shorter time without fear of Noise being introduced from the high gain level.
Here is a Screen Grab of Centaurus 'A' Galaxy at the crazy short time of only x96 sensup with Gain at max!
The image is very clean.
Thanks for reading this lengthy thread about my Cooling Project
...Any Pics sir ?? Patrick