Doesn’t the fan cause vibration? Is it turned off during shooting?

I am looking at the images on his site that he took. Can you see them that well with your own eyes through the telescope? I have always wanted to get into this but it just feels so unreal when I see the images people can get at home.

Instead of waiting an hour, why not put the camera in the freezer first, then use the peltier to keep it cold during the shoot? Might shave half an hour off cool-down time.

Luke, no they do not look that way in the scope. To get images like these you have to use a long time exposure. The scope will track the object in order to account for the earth’s rotation.

samuel, the water cools the hot side of the peltier cooler. The water never gets near freezing, but the more effective removal of heat from the peltier allows the cold side to get more cold.

If interested in long exposures, then read this thread discussing hacking a cheap Canon camera to add a Peltier cold-finger and reducing the CCD voltage during exposure to avoid the pink corner effect.

There’s no way a single man with a dslr camera, a telescope, and miles and miles of atmosphere can get pictures like that.

Where’s the pictures from observatories that surpass this quality?

@samuel: As others have mentioned, most water cooling systems use some kind of anti-freeze coolant mixed with the water. It has the added bonus of being able to hold more heat per volume than water too (or so I’ve been told).

@_matt: I’m not, personally, into this stuff but I’ve orbited around their community due to the really cool hacks they have been doing with software and digital cameras. After seeing what I’ve seen, I can believe that those pictures were home-made. There’s a reason why the impact detected on Jupiter yesterday was found by a hobbyist before NASA/ESA/etc. Some of these guys are INCREDIBLY dedicated and down-right brilliant. They’re willing to (like this guy) modify expensive digital cameras, buy/build the highest quality private telescopes, set up extremely long shutter rates, and implement some of the most complex atmospheric distortion compensating algorithms in order to produce the pictures you see. I rank amateur astronomers up there with a select number of hobby communities like Amateur Radio operators and Amateur rocketry enthusiasts where the top tier of the craft have shown themselves to be capable of accomplishing things that even most geeks wouldn’t think possible outside a corporation or government agency. If anything, I think the amateur astronomers even have a leg up on the other two hobbies as, at the very least, they don’t have to worry about, nearly, as much government regulation of their chosen hobby. One last thought, if you check out the caption besides a number of the pictures, it suggests that he is, also, going to special locations (with, I’m assuming, much lower light pollution) in order to take his pictures).

As for this project, I’m impressed by his results. Of course, as an armchair quarterback, I have to chime in with suggestions for how he might be able to improve the efficiency:

* A larger heat sink on either (or both) side may help.

* More importantly, he may want to replace the Styrofoam with some of the pink Dow-Corning rigid foam insulation you can pick up, extremely cheaply, from any Lowes/Home Depot store. The stuff he’s using right now looks like it might be the cheap stuff I got from Home Depot when I needed to block off the space to the right and left of my window air conditioner. I only went with it because I was feeling cheap that day and I wasn’t too worried about paying for a few extra kWh of electricity. For as sensitive a job as what he’s doing, I would think that he’d want every edge he could get. It comes in multiple different thicknesses and even the same thickness as the present styrofoam should provide much higher insulation values due to the fact that it’s specially designed for that purpose.

* Also, it looks like some of the edges of the aluminum box are showing through the styrofoam. He, probably, should make sure that the foam overlaps it’s self at the edges and that any other visible aluminum gets covered as any visible parts of the aluminum can be a bad source of heat gain. He may even want to go that extra step and look into using a small piece of foam pipe insulation (which can, also, be picked up extremely cheaply from Lowes/Home Depot) to wrap the first few inches of the telescope eyepiece where it connects to the camera box.

* He could, probably, further cut the time it takes to cool by removing the extra components he doesn’t need from the camera (the casing, the flash, mount the camera battery remotely, etc.). In the case of re-locating/rewiring the battery, this could be especially important as a battery being drawn from represents a significant heat source even closer to the image sensor than the Peltier system. An added bonus might be longer battery life as most batteries don’t work well in cold environments. Of course, if the removes the casing, then he’d have to be more careful about the potential for condensation on the electronic components. This might be avoided though the use of cheap silica desiccant like the stuff you find in the bottom of new shoes. Even if he didn’t want to crack open the camera’s case, he should still be able to wire up a battery mock up that allows a wire out to an externally mounted battery.

* While it may not improve cooling, he may want to consider trying to put a piece of fine wire mesh (like bug screening, but being careful to make sure it’s made of metal) between the inside fan and the camera. That fan on the cold side of the peltier set-up is very close to the camera and those kinds of simple motors are notorious for producing lots of electromagnetic interference. He may be introducing a new source of noise for the image sensor while trying to eliminate the noise caused by excess heat (though, obviously, the work he’s done has, definitely, produced a net positive).

* An obvious solution would be to buy a second cooler, construct another peltier unit, and mount if on the opposite side of the camera but, I’m sure, that’d add a lot more weight.

Like I said, I’m just armchair quarterbacking here but if any of these ideas help him, or anyone else, refine his technique even further (assuming he’s even reading these comments) then I more than happy to throw them out there.

This guy must be very passionate about this. Thats over a 700 dollar camera.

i always wanted to build the Cookbook camera, unfortunately i started about 10 years too late. anybody got any spare texas instruments tc211 chips?

Quote:

“@ colecomanm, the significance of the filter replacement is probably more than the peltier cooling, it increases the cameras sensitivity to Ha by 5x, this means 1/5th of the exposure time is needed to capture the same amount of data, this has many benefits, less noise in the image, less heat build up, less sky glow noise etc.”

@Reggie: I would, certainly, have thought so after seeing his graph showing the difference between the pass spectrum of the old filter vs. the new filter. My suggestions were intended to be in addition to the, already existing, filter swap.

This is awesome, I remember a few years back modifying a parallel port QuickCam for thermal imaging. Nothing fancy but it does work for higher temperatures. A company I worked for at the time was having problems with warping of metal after welding. I used the camera with the IR filter and colled down to show them heat transfer and develop a better “jig” and welding patern to keep warping from staying “warped” because the guys would weld the seam AFTER it has already shifted. Then when it would cool down. Bam… one bent and warped object. Any way. great work, I didn’t realize it could be used for this purpose too…..

not sure what the bayer filter does for things apart from add colour, not sure where abouts that is in relation to the sensor, but I’m guessing as there is no mention of removing it for DSLR and astro imaging then there is nothing to be gained from trying, as I’m sure someone would have by now :D

@Reggie it’s explained with sample pictures, when you remove the internal IR filter the colors go all off since the camera expects the normal visible spectrum, so to compensate when you take normal pictures with the camera you have to either use manual whitebalance and point it at a reddish card or use the simpler method of using an external bayer filter that does the same thing as the filter you removed namely stripping the IR out, that way you can still use the camera for normal photography but can simply unscrew that bayer filter to do IR photography, and put it in the cooling box for astro IR.
The bayer doesn’t add color, it removes IR.

Also, the page seems to imply that it’s “Baader” not “Baayer” so I’ve been misspelling it.

Seems I was partly wrong, they use the baader UV+IR filter to cut out the IR+UV in telescopes so the sensor gets more sensitive to the visual spectrum and thus gets more color in too.
Here’s the guy on his experiments with the baader filter and the reasoning:
http://ghonis2.ho8.com/rebelmod450d14a.html
The site baader uses and linked in this hackaday bit seems down though, but thy have this one (in german) http://www.baader-planetarium.de/default.htm