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Thanks and further on videoastronomy capture
Thanks to those who have responded to my requests for advice on video capture, and sorry for my late response - I have been away. After some trials with easycap and virtualdub I agree with Jeanette that manually duplicating the 99% or so of redundant frames is too tedious, and since it seems easycap itself (at least the one I received) is incapable of recording at less than the maximum 25fps rate, I will also change horses and get a Belkin device.
Jeanette, I went for virtualdub because that seems to be what those who had been successful with videocap were using. I no longer have any strong reason to prefer it, but having said that the software seems OK based on my limited experience. I'm not clear what the GStar software offers that virtualdub doesn't (noting that I have a Stellacam3 and not a GStar) but I guess I'll find out. Karl, AstroVideo also sounds like a good option though at some purchase price.
Jeanette and Tony, thanks for your insights on the actual DSO capture process - I had assumed leading from my own visual use that if an image had good fine detail in the monitor say at 128X that the camera would be recording that detail sufficiently at greatly lower integration rates (such as 8X) even though I couldn't see it on the screen, and only needed stacking and processing of an equivalent number of fresh 8X images to bring it out. But it seems from my limited practice that stacking say 120 such unique images is nowhere near as effective in bringing detail out as increasing the integration from 8X to 128X; ie. a relatively high level of integration in the camera itself (say 64-96X or so, or more for faint objects) is still necessary as a starting point. In other words, you need to be able to more or less see on the monitor what you are going to capture. Let me know if you agree or not with this.
Another thing that has just dawned on me; the 128X (for example) that GStar and probably Stellacam quote as taking 2.56sec must signify half frames rather than full ones, since 25fps*2.56s = 64 frames.
Cheers,
Andrew
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