Observing Log-Jupiter

davidpretorius · #1 02-08-2005, 10:06 AM

Date: 2/08/2005
Time: 20:30
Loc: 41'25"S, 147'07", UT +10
Apert: 10" Reflector
Mount: dob
Cond: hazy to aprox 20 degrees
Seeing: 6
FL: 1250
EP: 6
Mag: 208
Filters:
Object: Jupiter
Type: Planet
Const: Spica
Magnit: -1.8
Size:
RA: 12h51m05s
DEC: -4'10"50"
Comments: Got the toucam lined up nicely, did a 10 - 15 passes to get the exposure settings right. Very happy with results. Still need to collimate
Avi sett: Toucam, prime focus, 1/100, bri 100%, sat 100%, gamma 50%, gain 100%
Avi link: http://www.precons.com/iis/gallery/M...05-jupiter.wmv
Image sett: Registax pretty much standard settings, Photoshop 7.0
Image link: http://www.precons.com/iis/gallery/I...05-jupiter.jpg

I played with the wavelets in registax and ended up with this image

the top three settings in wavelets left as is, and moved the bottom three, wuth the 6:1 set to say 4

ving (David) · #2 02-08-2005, 12:33 PM

getting there dave!
got some stripage (is that a word?) on the ball!

well done.

davidpretorius · #3 02-08-2005, 12:36 PM

Ving, not sure if you got to post as i was editing and have added a wavelet version, much more detail

iceman (Mike) · #4 02-08-2005, 02:18 PM

Nice work David, you're on your way.

Quote:

Avi sett: Toucam, prime focus, 1/100, bri 100%, sat 100%, gamma 50%, gain 100%

Gain 100% is way too high - your aim should be to have gain as low as possible. Start with gain at 0, and adjust your shutter speed until there's no bright washed out areas. Then, if you need to make it a little brighter, adjust the gain upwards. But I would never go above 30% with gain, you'll get too much noise and your image will be all grainy.

Brightness 100% - I leave this default at 50%, always. As I said above, use the shutter speed and then gain to adjust your exposure.

Gamma 50% - I leave this at 0 (or, more accurately, all the way to the left) which means "maximum contrast". The camera will work out the best setting to get max contrast, which is what you want.

Have you got a link to the original avi? I'd be happy to have a go at processing it for you if you'd like. Your effort was quite good though, playing around in registax is the best way to learn it, but I do mean to write that guide soon. (Tony, i'll answer your q's soon).

One last request, your signature is way too long. See the forum posting guidelines, it's requested to have it no more than 4 or so lines high. Can you please amend it a bit? Thanks

Oh one last thing, it's great that you're getting into the imaging, but don't forget to use the eyepiece sometimes too.. you've only just got your scope and there's some wonderful things to look at with your eyes, instead of having your head in a laptop screen and continually moving the dob as the object drifts out of the FOV. I know, I've been there

I enjoy imaging a lot but I need to keep reminding myself to give myself some eyepiece time and relax with the telescope, avoid the stresses of imaging.

So that's my advice.. you've only just got your scope so spend some time with it before you get full-on into imaging.. I suppose though if you spend long enough each night outside, you may get to do both.. just don't neglect the observing, is all i'm saying

oh and I do understand that you would want to get better at imaging to get some good planetary imaging before Jupiter gets too low.

I've rambled.. bye

davidpretorius · #5 02-08-2005, 03:30 PM

Thanks Mike, signature all fixed. Don't worry about the eyepieces. The 30mm 80 degree ultrawide arrived yesterday and it is beautiful. I start with the eyepieces and have a good look around by star hopping. Test to see if i can find what i found the night before and look for anything new (referring to starcafe online).

Then i get into imaging for a while and then to finish off i treat myself to simply pointing it at random and using the ultra wide, simply pushing the scope and browsing.

ving (David) · #6 02-08-2005, 03:43 PM

oh yeah... that wasnt there before!!!

nice

asimov (John) · #7 02-08-2005, 05:22 PM

Nice Dave. Now do as Mike suggested...(& me awhile ago) Put the camera back in it's box & do some visual stuff? Just a suggestion Dave, do as you like though...& ENJOY!

davidpretorius · #8 02-08-2005, 06:53 PM

don't worry asimov, the camera is 1/4 time spent, mainly to share with you guys what i am seeing, whilst 3/4 of the time is eyepiece. especially with the excellent 30mm ultra wide!!!

asimov (John) · #9 02-08-2005, 07:21 PM

That's good Dave....Got my 2" out last night as well on a couple of objects. Not all that crash-hot with the F/5.25 newt...I think the 24mm 1.25" does a much better job for wide-views. In the F/8 refractor the 2" does good....(my reason for buying the 2") So it really depends on the F ratio of the scope as to what EP works great, or just average.

A newbie can blow a lot of dough buying EPs that give an average view.

asimov (John) · #10 02-08-2005, 08:18 PM

Dave. I just picked up on a comment you made...."Still need to collimate"

Can you tell me why you would think that it needs collimation? I'm Asking for no other reason than to analyse how you came to that conclusion....

davidpretorius · #11 02-08-2005, 08:40 PM

Three things for thinking slightly out of collimation.

1.. a very learned gentlemen (asimov) commented from the original mars video i did, that it was a little.
2.. stars don't come to a point on very high mag, they elongate
3.. looking down the focuser without eyepiece, all the mirrors don't line up perfectly. I used the cheshire tonight to line up secondary and now just have to adjust primary. Not sure how to adjust primary. I do not want to muck around with screws on the bottom of scope until i know what each one does.

I read that article you posted a week or so ago. I may take a shot if i can to show.

anyway a noobie assessment!!

asimov (John) · #12 02-08-2005, 09:06 PM

No worries Dave.
1 This 'asimov' may have been wrong.
2 This is a DEAD give away! confirming that 'asimov' was right.
3 ......not applicable
4 Thanks for your thoughts!

iceman (Mike) · #13 03-08-2005, 06:35 AM

Quote:

stars don't come to a point on very high mag, they elongate

Don't forget that could also be astigmatism, due to pinching of your primary and/or secondary mirror. Read Geoff's how-to article for isntructions on how to remedy this. It's a must-do for GSO dob owners.

asimov (John) · #14 03-08-2005, 12:07 PM

Ah yes. I forgot about that problem.

iceman (Mike) · #15 04-08-2005, 07:30 AM

Dave sent me a link for the full avi, which I had a go at processing.

A couple of comments:
- Focus looks good
- Start the avi once Jupiter fully enters the FOV, it'll make processing easier.
- Soon you'll want more image scale, and you'll have to start using a barlow. It makes things much more difficult as it flies through the FOV in half the time.
- Settings (brightness, gamma etc) not quite right as I said above, look forward to seeing your next attempt with tweaked settings.
- I couldn't get much different than your processing attempt (good job).
- Stacked 100 frames in registax, wavelets processed, colour balance adjusted.
- What frame rate did you use? Going by the length of the video and # of frames, it looks like you use 15fps. I'd suggest using 10fps in bad or average seeing, and 5fps in good seeing. The reason for this, is the ToUcam has to compress data to shove down the USB 1.1 pipe. The higher the frame rate, the more compression is needed. So in good seeing, you want the data compressed as little as possible, so use 5fps. When seeing is worse, you want more frames to be able to select the best, so use 10fps. Any more than that, you'll get more compression artifacts.

davidpretorius · #16 04-08-2005, 08:15 AM

thanks mike