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RickJ
2008-Feb-06, 09:42 AM
I don't have a good set-up for planetary work. A mono CD is probably the worst tool for it possible. It takes about 15 minutes just to take 4 lum and 4 RGB each. By then rotation is too much to continue and you start a new set. In that time a web cam would have taken a thousand frames. The good ones stacked and the result a pretty darned good shot. But I had to pick the best out of each of 4 and just use one shot in effect. I tried three such sets. This is the best of the bunch. Also I have no way to put a barlow into the system so this is pure prime focus at f/10. Working at f/20 or more is much preferred. But you go with what you have and hope. Maybe next opposition I'll have a better system for planetary work. Taken with my 14" LX200R. I tried to process it naturally as it looked in the eyepiece without pushing contrast. This was my last shot of 2007. Or the first of 2008 if you use UT.

Rick

JAICOA
2008-Feb-06, 07:36 PM
Hi Rick, you did super on Mars and in color. You didn't mentioned which ccd you have and not having a barlows makes it more difficult. On this photo i used my ST402ME ccd and at a setting of 0.04 of a second with a F6.3 focal reducer. High speed for movement and a focal reducer for more light. Clear skies my friend.

RickJ
2008-Feb-06, 08:30 PM
I've got barlows and powermates but no way to use them with the STL-11000, same as I use for my deep sky stuff. Everything there is set for a 3" opening and no way to mount even a 2" barlow in my set-up. I need to get a good web cam but haven't as yet. I used the STL-1100 as it is the only thing I have RGB filters for. I have an ST-7 but its got photometry filters not RGB. The 9 micron pixels are large for trying to work at pure prime focus. I don't recall the exposure. It was under 0.01" as my header says 0.00". That's a display rounding problem. The exact value is in the header if I want to dig for it. CCDSoft's default display of the header rounds to two decimal places. Still Mars hit an ADU count of 25000 which is about the max and still be linear with this AGB chip. I didn't lack for light!

Nice Jupiter. I've not even tried it. Maybe in a few months. It's rare for my seeing to be very good and since I can only snap one frame every 40 seconds or so getting even an RGB series with Jupiter's rotation rate means I gotta hit perfect seeing three times in three tries. Not likely to happen. Mar's turns slower giving me 4 tries each color before it rotated too much. Fortunately, the sharpest of the bunch was an L image so went LRGB to hide the problems with even the best color frames. Actually, I should have used the Guider chip as it's readout is very fast. Noise is high but with a bright planet that shouldn't be a problem. Then I could get dozens of shots a minute. Didn't think of it until now. Even isolating a small part of the STL-11000 results in a very long delay before readout begins. Doesn't really help much. Though moving it to the guide chip gets the image out of the zone of highest resolution. So maybe that wouldn't work well. The web cam is the cheapest route and I can use that with a barlow very easily.

I'm not much of a planetary shooter so hard for me to get all that interested!

Rick

winensky
2008-Feb-06, 11:20 PM
Great work Rick. I have all but given up on the idea of planetary work for the moment as even with the barlows I am at f/8. My DSI II has a webcam mode so it can manage a lot of exposures but for prime focus its just too much light, too little magnification and not enough contrast...not to mention refocusing between filters. You have done well.

Kind regards
Matt

RickJ
2008-Feb-07, 01:32 AM
Matt,
You could stack a 3x barlow and get it to f/24. That works well from the results of those that do it in our club. But a one shot web cam is the best way to go. My filters all come to the same focus. I'd be dead in the water if they didn't.

I almost had too much light here. Checked the full header and the exposure was 0.001" which is the shortest I can do and the ADU count almost hit the non linear part of its range. The only way I can image the moon is through the Ha filter! Otherwise it saturates the CCD. I had a web cam but one of the grand kids pulled it off the shelf. I didn't see it and stepped on it. Now I need a new one! It was only USB1.1 so too slow and a lot fewer pixels than those of today so no real loss.

Rick

winensky
2008-Feb-08, 02:02 PM
Ah yes my barlow is 2X and a good one but my next investment will be in a guide scope and cam. Thanks for the encouragement

Kind regards
Matt