Length of Avi files for Saturn

[Moonwalker3]

Hi! I wanted to know how long I should film Saturn for through my webcam (SP900nc). Typically are longer Avi files better as there will be more good frames kept? Last time I got 1,700 frames and I got my best image of Saturn ever but if I had like 8,500 frames then I should hopefully get more detail? Thanks, Andrew.

[Mattscar]

Hi Andrew

I'm sure thats the right idea - more frames = more possible good quality frames to get detail from. I'm only just starting out on this myself, but I'm sure you can go higher than 1,700 frames. I'm sure someone who knows what they are on about can give you some actual numbers to work with

[Moonwalker3]

Thanks Mattscar! I can go higher than 1,700 frames and tonight looks like being clear so I might try and get 5,000+ and see what magic RegiStax can weave! Although as you say I will wait and see what other people think :-)

[Mattscar]

5,000 sounds a good number for me to try aswell, last time I was cloud dodging like mad. Though I did manage to stack several videos together from that, so maybe two 5,000 frame videos would be worth a try.

I'm not sure how many I can get with my mount before its drifted too far so 5,000 seems a good as any number to try.

[Moonwalker3]

I'll give that a go and show you what the final results are later! Right I'm off to get my equipment out now so hopefully it's clear where you are as well.

[Mattscar]

I'll happily compare results tomorrow night when Iv had chance to process. What equipment are you using?

[Moonwalker3]

This is just a quick processed image as I've got to get up early! I used a Celestron C8 XLT with HEQ5 synscan mount. SPC900n webcam attached to a 2x barlow lens! The 5,000 frame avi didn't work that well as it slightly drifted too much making it out of line.

[JamesF]

You can use PIPP to sort out some of the alignment issues to allow you to use more frames. With the C8 I'd have thought you should be able to grab five minutes worth of video without any major problems because of the rotation of the planet, but I'll try to check later when I'm not outside myself

I wrote up some information last year about capture times and so on for planetary imaging. I'll also find the link for that later and post it.

James

[JamesF]

(By all means prod me to remind me if I forget. Monday's are usually a bit hectic.)

James

[Mattscar]

Even if youv not done much processing on there I think its still going to be better quality than mine. I managed to get 2 5,000 frame videos at different resolutions so I can compare them. Won't get to do the processing untill late tonight though.

[JamesF]

Ok, in theory, with the two metre focal length of the C8 and the SPC900 you could probably go for three minutes per capture run. In practice you can probably double that without pain.

If you'd like all the gory details, they're here:

http://www.tanstaafl.co.uk/2012/03/focal-ratio-capture-length-planetary-imaging/

James

[Mattscar]

This is 5000 frames at 20fps through PIPP and Registax. I'd like to believe the cassini division is visible, as I certainly saw it through an EP before doing this, but I'm a little unsure.

Saturn 640 20fps 02_06_2013 by A Drummers Space, on Flickr

[JamesF]

There are darker lines there that are probably are the Cassini Division. They can look a bit oddly-positioned in lower resolution images.

James