Working 1100D cold finger sensor cooling with TECs and water cooling

[Gina]

I've succeeded in resuscitating my apparently dead camera Took it apart, took the power circuit board off the battery holder, cleaned the battery contacts and checked the memory backup battery and put it back. Reassembled everything and it worked Of course that was a few hours after I ordered a refurbished one from eBay. Never mind, I'll have a spare or I might do the filter mod and sell it. I'll do the filter mod anyway.

[ih8usrnames]

I finally got back to working on mine. I have removed the following and it still works fine:

Front panel

Rear LCD/Buttons - removed-disconnected

Flash Assembly - wires cut, completely removed from camera

Flash Capacitor - discharged and cut from the board

AF sensor assembly - completely removed, cables disconnected

Lens electrical connections (pins that interface with lens for AF) - removed and disconnected completely

Learned I can operate without viewfinder display ribbons connected.

If I can figure out a way to have this operate without power switch and mode dial then I will remove the top cover and pantaprism assembly to make it smaller yet.

Pattern for cold finger has been made though not installed.

Made patterns for the EOS mount today so I can make/drill out a T-Adapter or I can use the Teleskop m42-EOS http://www.optcorp.com/product.aspx?pid=17696&kw=EOS&st=2 - bypassing the eos mount. I can then place a glass filter between the T-Thread adapter and the box housing the camera to create an air tight unit and possibly purge air with some dry inert gas.

Ditching the EOS mount and going straight M42 will shorten the optical path, even if with a filter in place, and possibly give me more options in OAG's.

[Gina]

I finally got back to working on mine. I have removed the following and it still works fine:

Front panel

Rear LCD/Buttons - removed-disconnected

Flash Assembly - wires cut, completely removed from camera

Flash Capacitor - discharged and cut from the board

AF sensor assembly - completely removed, cables disconnected

Lens electrical connections (pins that interface with lens for AF) - removed and disconnected completely

Learned I can operate without viewfinder display ribbons connected.

Yes, I've done most of that too. I have a smaller box I would like to use.

If I can figure out a way to have this operate without power switch and mode dial then I will remove the top cover and pantaprism assembly to make it smaller yet.

Yes, indeed! I've been pruning pieces of plastic off the top section to reduce the size. Have removed the flash shoe and front lens of viewfinder. The problem with going further is being able to retrace steps if it stops working. Actually, I think I may have done that already (but I have a spare top from a camera I succeeded in destroying earlier). At that point I gave up on it yesterday and haven't touched it today but I will be getting back to it - just need a break and give my fingernails time to regrow

Pattern for cold finger has been made though not installed.

Made patterns for the EOS mount today so I can make/drill out a T-Adapter or I can use the Teleskop m42-EOS http://www.optcorp.c...696&kw=EOS&st=2 - bypassing the eos mount.

That's alright if you can be sure of preserving exact alignment (mount at right angles to light path). I thought of doing that but it didn't work out for me. I'm using the focal reducer for my scope and clip filters which I need access to.

I can then place a glass filter between the T-Thread adapter and the box housing the camera to create an air tight unit and possibly purge air with some dry inert gas.

I find using silica gel (4 10g bags) reduces the moisture and stops condensation down to -5C or more.

Ditching the EOS mount and going straight M42 will shorten the optical path, even if with a filter in place, and possibly give me more options in OAG's.

That's certainly true.

I'm looking into the possibility of incorporating a filter wheel into the box the camera goes in. If you get in close to the image sensor (eg. just in front of the shutter, you can use 1.25" filters (the flip mirrors can be removed). I'm using narrow band clip filters with the 1100D though only have Ha so far. A 4 filter wheel would be plenty viz. none, Ha, OIII, SII. Of course, colours are catered for by already having a colour sensor But as I said above, the problem is maintaining perfect alignment.

[ih8usrnames]

I spent about an hour going through all the ribbon cable in the top seeing if I could make sense of it then decided good enough was good enough.

I have not looked into it yet but I would like to ditch the flip mirror, there is absolutely no need for it. If you ave knowledge about this or links I would be very interested in it.

[Gina]

I spent about an hour going through all the ribbon cable in the top seeing if I could make sense of it then decided good enough was good enough.

Yes, I too had a good look at it and gave up - so many tiny tracks going this way and that!

I have not looked into it yet but I would like to ditch the flip mirror, there is absolutely no need for it. If you ave knowledge about this or links I would be very interested in it.

I read that someone else had removed the flip mirror saying that it had no sensors to detect its position so it was safe to remove. I haven't removed mine yet.

Here's a couple of pics of the butchered camera fitted into the smaller ABS box.

[fwm891]

I think it was yesyes who removed his flip mirror on a 1000D?

[Gina]

Quite possibly

[yesyes]

Indeed. But I don't know yet whether it still works. It's all in little bits in antistatic bags. I wanted to sort out the cooling problem before making an enclosure and test everything.

[Gina]

Well... I put the other top on the camera, fitted battery etc. and shutter release worked the shutter. However, when I opened the battery cover, before taking the battery out it started beeping - not had that before. More testing needed I can connect it to a computer and/or put a back on with display screen to show any error. The cloud has come back and I shan't be imaging so I can bring the netbook indoors.

I've completely removed the viewfinder and penta-mirror unit but the top remains the main problem. If that could be removed it would save a whole inch from the height! It may be possible to dismantle the top except for the mode and on/of switches, being careful not to harm the ribbon cable/circuit.

Apart from this ultra extreme modding I'm looking into making up a box that will take a camera with top part intact, including all the lumps and bumps. There will still be the filter and cold finger mods though. I might make a slightly different cold finger to raise the TEC to allow a heatsink to sit above/behind the back of the top. Yes, there's still plenty of experimenting to do

[Gina]

Indeed. But I don't know yet whether it still works. It's all in little bits in antistatic bags. I wanted to sort out the cooling problem before making an enclosure and test everything.

Ah that's the crucial point - does it still work?! The cooling depends on the heat produced by the sensor of course. I'm aiming to get the heat produced by it all low enough to use an air cooled system. One way of increasing the cooling efficiency of heatsink/fan combo is to raise the temperature and go for two low power TECs cascaded.

[Gina]

I did both - connected to netbook and put a back on. The backlight on the screen comes on but no display except a quick flash something about the internal battery when I pushed one of the buttons. When I push the shutter release half way the screen backlight goes off. In Tv mode the shutter speed thumbwheel setting is displayed in EOS Utilities so some things are working. I've more testing to do but I don't think that will be tonight.

[Gina]

I have now abandoned water cooling and gone for air cooling so I will be adding no more water cooling info. I have just removed the water cooling bits from my mount.

Thank you for all contributions to this thread - it was an interesting experiment and produced some good results but in the end the complication was just not worth it.

[nightvision]

What was it about the water cooling approach that put you off (you were certainly getting some very low figures at the sensor)?

[Gina]

What was it about the water cooling approach that put you off (you were certainly getting some very low figures at the sensor)?

I found it awkward to take the camera off to change adapters (eg. FR/FF) or clip filter. Cables can be unplugged but if the water tubes are unplugged the water (plus additives) runs out. So I did experiments to see if I could achieve sufficient cooling without increasing the weight unduly using an air cooler. If I decide I want to go really low in sensor temperature and I can get the humidity low enough to prevent condensation I may go back to water cooling. ATM the amount of cooling seems more than adequate but "the proof of the pudding is in the eating". With my new camera arrangement I can easily swap the CPU fan cooler for a water block.

[Gina]

I think it was yesyes who removed his flip mirror on a 1000D?

The flip mirror weighs so little I shan't bother with removing it - tricky job anyway.

Regarding the possiblitity that I might go back to water cooling... the water block, pipes and coolant weigh around 100g for the first water block I used (ThermalTake) whereas the Zalman air cooler weighs 320g. Also that WB I have fitted with unions which make it easier to disconnect though it's still necessary to drain the coolant out of the WB and pipes.

I'm prone to changing my mind on things

[yesyes]

The flip mirror weighs so little I shan't bother with removing it - tricky job anyway.

True. I didn't remove it for its weight but to eliminate the vibration. On my 1000D mirror lock-up can't be done via USB but I would need a serial shutter release (which would also add weight again).

On the 1100D this doesn't make sense as you can use mirror lock-up over USB.

[Gina]

True. I didn't remove it for its weight but to eliminate the vibration. On my 1000D mirror lock-up can't be done via USB but I would need a serial shutter release (which would also add weight again).

On the 1100D this doesn't make sense as you can use mirror lock-up over USB.

Ah - I didn't know the mirror lockup (or live view method) via USB didn't work with the 1000D.

[yesyes]

the "live view workaround" works with the 1000D. But since it's using live view it's causing amp glow after a while. Real mirror lock-up requires a shutter cable with Digic 3 cameras. Digic IV cameras support true mirror lock-up via USB.

[Gina]

the "live view workaround" works with the 1000D. But since it's using live view it's causing amp glow after a while. Real mirror lock-up requires a shutter cable with Digic 3 cameras. Digic IV cameras support true mirror lock-up via USB.

Ah, I see.

[ih8usrnames]

I ordered an Antec Kuhler 620 for my system, it is a sealed system. I will mod the water lines making them longer. My only concern is potential vibration, the water pump is integrated with the water block. I imagine, however, the vibration from the pump can be no worse than from a fan on a traditional cooling system.

I spoke with an engineer who specializes in thermoelectric coolers after sending him drawing and information about cooling the seonsor . Considering what I'm trying to accomplish he feels this is the proper unit for the job: http://www.tetech.com/Peltier-Thermoelectric-Cooler-Modules/Standard/TE-127-1.0-2.5.html I was able to acquire one of the TEC units but it was tough, they have a minimum $85 order.

He mentioned the import TEC (chinese, taiwan, etc) units are not all that efficient - imports can be usually be identified via the model number 1270x.

I do not have the Kuhler 620 or the TEC yet, both in transit.

[yesyes]

Hmmmm, that makes me wonder whether my problems come from duff TECs. Mine are all of the 127xx variety.

[Gina]

The ones I've found best were from a UK seller but whether they originate from China I don't know. The seller provided no model number and they were unmarked. But even these are inefficient I'm sure and I've often wondered if much better ones were available at a price. To get away with a single TEC the hot side needs cooling to just a few degrees above ambient. So requiring water cooling or a great big heat pipe CPU cooler.

Having done a lot of experimenting with both water cooling and air cooling I have succeeding in providing a sensor temperature of between -10 and -20C. The water cooling is still more efficient than the air cooling by about 2C and the water cooling is 200g lighter at the camera. But air cooling doesn't need water pipes and instead of the radiator being mounted away from the camera with piped water circulated by a pump, the radiator is moved onto the camera. So there are pros and cons of both systems.

The Zalman Reservator has coolant connectors with automatic valves that close when the pipes are disconnected from the radiator. These are plastic and lightweight and block off leakage from both sided - only a drop or two of coolant escapes. I don't know if these could be obtained separately but if they could they would overcome what I cobsider a main disadvantage of water cooling viz. being able to disconnect the camera without having to drain the system..

[ih8usrnames]

From what I was told real differences between the imports and what he sold me is the density of thermoelements. I believe height may play into it as well.

The engineer and company are based in Michigan (shaped like a mitten). The Michigan economy is horrible so I gladly spent my money there.

This may be similar, if not the same thing. http://www.quick-cool-shop.de/peltierelemente-thermogeneratoren/peltier-element-einstufig/thermoelemente-qc-127-1-0-2-5.html

[HenrikSchneider]

Gradually tidying up the cooling parts. These photos show how the cooling parts fit together. Next I have to work out how to hold things in place.

1. 25mm square TEC on cold finger.
   
2. Intermediate copper plate on top of 25mm TEC.
   
3. 40mm square TEC in place.
   
4. Water Block on top of 40mm TEC.
   

This is a brillant setup

What happent with the back-plane electronic, and display unit?

Can it just be removed and the the camera is stille working via USB or is there a requirement for chance in the camera SW?

[Gina]

This is a brillant setup

What happent with the back-plane electronic, and display unit?

Can it just be removed and the the camera is stille working via USB or is there a requirement for chance in the camera SW?

Thank you Yes, the display and all the bits on the back part of the camera are not needed - everything can be controlled via USB.