image source help
Posted 30 March 2009 - 12:33 AM
Posted 30 March 2009 - 12:09 PM
Basically, the USB camera's don't require an external power supply, while the Firewire ones usually do (Firewire ports can be "powered", but this is very rarely the case on laptop computers, in which case you'll need to supply power through either a powered firewire hub, or a PC-card which can take a power supply).
For the rest, there is virtually no difference in performance or results between them - on older PCs (say 4 years or older) you may get better results with the Firewire camera's because they require less CPU, but on a modern PC the overhead for that is pretty much negligeable.
On the question of "what type", the answer is again "it depends"...
The DMK21 is by far the better camera for planetary imaging, being more sensitive and capable of 60fps (especially on rapidly rotating Jupiter, having more frames in less time is *very* useful).
The DMK31 & DMK41 are better for lunar or solar imaging, because they have higher resolution - you can use mosaicking to create bigger images, but the smaller the camera, the more complicated, timeconsuming and difficult that becomes. The moon & the sun usually are bright enough that the lower sensitivity isn't quite such an issue, and the slower framerates aren't quite as problematic because most change is slower (except perhaps for some fast-moving protuberances on the sun).
I've got a DMK21 and a DMK31, but for starters, I would say the DMK21 is the easiest camera with the most flexibility (and need I mention it's the cheapest of the bunch :-)
Posted 30 March 2009 - 12:52 PM
But for more information, you can read my review:
Review of the DMK41AF02 with High Resolution Images
For the DMK31, the AstroVid Voyager X is similar, and I did a comparison with that one a few years back too:
Astrovid Voyager X - Planetary Imaging Camera
Hope that helps.
Posted 30 March 2009 - 11:33 PM
Dont know if that works for your cameras, but I have used it on other projects where I needed some power for a peripheral device.