Mars 20th nov. 12.5"+good Ol' toUcam

[asimov (John)]

Hi.

Most of these are 'over-processed' I know, but I'm just experimenting/learning the ropes.

I've had a kink thrown into my image scale logic! These are at prime using the F5 reflector (with 2X barlow = F10) yet their twice as big than shooting with the refractor (F8 with diagonal & 2X barlow = F24 roughly!) ???????

Anyway, I found out shooting at this mag with this scope my polar alignment is up the.......so I only got like 200 odd frames & the result is 101 frames stacked.

Anyone want to buy a 6"achro refractor??

Can't wait to get a decent polar alignment & get 2000 frames!!!

[Robert_T]

Hi Asi - nice shots, a big patch of cloud there over some of the albedo features. That's wierd re the image scale. Is it possible you changed from running a different format such as 320x290 on the refractor to 640 x 480 on the reflector as that will certainly create a different image scale?


cheers,

[davidpretorius]

They are great, there sure is some potential in the old girl!!!!

when you say over processed are you talking wavelets or deconvolution in astra image or some other process .

do you have a vid you can compress and send me to play with.

well done.

[davidpretorius]

Originally Posted by asimov

These are at prime using the F5 reflector (with 2X barlow = F10) yet their twice as big than shooting with the refractor (F8 with diagonal & 2X barlow = F24 roughly!) ???????

All i know is that at prime focus, the old girl will be putting out 1800 / 6mm = 300x and with a barlow, 600x

The focal length of the refractor is not that big is it???

[asimov (John)]

Hang on, I'll have to do some calculations to determine it's exact focal length...it's not a TRUE f5 scope....

[davidpretorius]

1800 / 12.5 = 5.6

[iceman (Mike)]

asi, it's focal LENGTH that determines image scale.. focal RATIO is related to the brightness.

Your 12.5" newt is 1800mm FL, whereas your refractor is what, 800?

That's why it's bigger.

Great pics too, you're getting the hang of that webcam!

[asimov (John)]

Ok...the reflector is axactly F5.0473186...near enough to F5 to not make a spot of difference!

Yes, the refractor is F8 + 2X barlow + diagonal which I have read...gives close to 3X (with barlow) = F24 ....or is this wrong??

[asimov (John)]

Focal length of primary is 1600mm exactly.

[iceman (Mike)]

Check my reply above yours asi, we posted at the same time.

Your newt, with a 2x barlow = 3200mm FL.
Your refactor, with a 3x barlow = 2400mm FL or there abouts.

When talking about image scale, it's best to always talk about focal length as opposed to focal ratio.

[asimov (John)]

Aaah! All too complicated for my pea brain lol! Who cares!? Throw the refractor back in it's hidey-hole...

[Striker (Tony)]

Yep what Mike said....F ratio is only the ratio of aperture to Focal length....

It's the focal length that gives you the scale.

See I said Houghy post would confuse people...lol

[asimov (John)]

Thanks Mike. Yeah, I see it now...3200 focal LENGTH!!

[asimov (John)]

Anyone ever cried at the scope...cos' I nearly did! seeing was 9.5/10!! And I managed to get 200 frames! Well DONE asi-dummy!

[davidpretorius]

it is so rare where you live, but i hope you enjoyed it.

i felt like a mini asimov last night, star testing for about 30 mins. a tweak here a tweak there.

It was so rewarding then zipping over to the trap and seeing pin points!!!!! 5 stars on a moon night, i was very happy!

[asimov (John)]

It was a total comedy of errors last night Dave! Everything that could go wrong did! 3/10 seeing for the first 3/4 of the night, so by the time the seeing got to 9.5/10 mars was well on it's way to setting in the west. (about 25 deg) Gusts of wind everytime I went to shoot! Power failure at 2.30am. for about 2 hours. I was halfway thru processing an AVI when it went down. Got on the blower to AGL...they said it was my curcuit breakers! Do my house curcuit breakers operate the street lights of my town as well!??....Dummies.

Apart from all that...YEP!! I enjoyed myself immensely!! The best part is that feeling when you see that image popup just after stacking the frames!! Can't beat it! (even if it does turn out to be a crap image) The next bit is QUICK! upload it to the forum for the guys!! QUICK!

Sounds like your getting the hang of the collimation, that's great! It will be second nature to you soon.

[ving (David)]

wel done asi. I like em.

[RB (Andrew)]

Originally Posted by asimov

Power failure at 2.30am. for about 2 hours. I was halfway thru processing an AVI when it went down. Got on the blower to AGL...they said it was my curcuit breakers! Do my house curcuit breakers operate the street lights of my town as well!??....Dummies.

FCOL it's a wonder they didn't blame you in the end for the failure to the whole area for operating telescopic equipment off the grid.

Nice images Asi, I especially like the first 2.

[asimov (John)]

Thanks RB! Yeah, the first 2 are the most natural looking aren't they. The others...well I just wanted to see how far I could tweak them in different programs.

Yeah LOL! it was my HUGE laptop and 6V stepper motor on my RA drive that sent the grid crashing!