Noobie Diary part 7 - first night summary

[davidpretorius]

Hi all,

Well, the first night is over.

Put finishing touches on assembly at around 6.30pm last night.

Small video here http://www.precons.com/iis/gallery/The%20girls%20and%20the%20telescope %20small.wmv

Large (1mb) here http://www.precons.com/iis/gallery/The%20girls%20and%20the%20telescope %20large.wmv

The assembly went well.

Carrying assembled unit all in one hit down the stairs.... ummmmm.... Wheres those scope buggys Mike? want my credit card details?

Loved looking at the sky, Thru the 6.5mm Jupiter looked the size of your nail on your little finger held at arms length. bands could be seen. Loved the moons, Didn't expect to see them and there they were. Even in the 40mm, they were there.

Took time to get used to everything being upside down, but you get the hang of it ie push left on scope to move right, push down on scope to move up.

Time came for sharing with the forum guys. Sadness ensued. Got out the toucam and removed the lens, connected the adapter. Removed the eyepiece and inserted the webcam and adapter into the scope. NOthing!!!!

Hours later, i tried again, but had been thinking on how to focus this setup. Had read about Mike and the Hartmann mask, but seemed a lot of work to do there and then and at night. So I simply focused on a street light aprox 200m away. Success, i got the image on the computer to focus.

Right, now where is mars?

aprox 2pm, there is mars. I must really recommend skyviewcafe.com - great for finding out what is happening and where, updated in real time as the earth rotates. Ok here we go, point scope with toucam at mars and see what comes up on computer,

small version : http://www.precons.com/iis/gallery/20050729%20mars%20unfocused%20small .wmv

large version: http://www.precons.com/iis/gallery/20050729%20mars%20unfocused%20large .wmv

As you can see, i can't get the focuser to go any further into the scope. There must be a way. I shall put it to the forum who may be using 2" crayford focusers and toucam with adapters (Mike????)

Promised the wife I was coming to bed at 2.30am, but one look at starcafe showed the moon was getting higher, but the clouds weren't letting her thru.

2.45am.... success, out cam the moon. I had put away the computer and toucam so i could go to bed, so out came mr 40mm and wow!!!, out went mr 40mm and in went 25mm ooooooooooh, and again with 12.5mm, bl**dy hell......clouds coming, quick get that 6.5mm in... holy sh&t that is awe inspiring. What a way to finish the night.

Asimov, I know i said i was having a great time but very calm, but that little 30sec observe of the moon between clouds sent my heart racing and a grin from ear to ear

I'm Hooked!!!!

[elusiver]

i guess the curse mustn't apply to people with six toes :P ;) j/k

u should be thankful.. u were very lucky to get it out the night you got it.. and it sounds like u had a ball!!

did u manage to try the moon with the moon filter? u get a bit more detail and it's also less blinding..

el :)

[davidpretorius]

moon came out late literally as i was about to pack up and go to bed. I had 30 secs to view it roughly. where does the filter go, but the way? I did have a quick look at the filter itself, saw it had a thread, but not sure where in the link to put it.

yes it was great, i was very lucky with the weather. it was raining the night before and raining today!!!

[xstream]

Glad to see you were lucky enough to have an enjoyable first night Dave. :D
BTW the F/T screws into the base of your eyepieces. ;)

[ballaratdragons]

Dave,

That was an excellent write up. Love the Video. See, boxes are very handy for all sorts of things!!

That excitement of yours sounds familiar.

[ving]

your umm... mars shot is interesting... so you pulled the lens out out of the webcam didnt you?

[davidpretorius]

thanks all for comments. Have just came back from lunch and tried focusing the webcam in prime focus setup. Like last night, the lens of the webcam came out, the 1.25" adapter went in. In this setup, i can focus well on land based objects up to say 100m away. Past that, i have to take the 1.25" to 2" adapter in the focuser off and push the webcam into the 2" hole and then i can get focus on land based objects say around 10km away.

As you can see by the infamous "one night in mars" video i shot, i am at the minimum travel of the focuser late in the video, but still not at focus.

here is my attempt without the 1.25" to 2" adapter in the focuser and the webcam shoved in the 2" hole by hand

http://www.precons.com/iis/gallery/20050729-001%20terrestrial.wmv

I still have a bit of room to play with as i came back from minimum travel to focus. But still the ccd of the webcam is closer to secondary mirror than wih the adapters in and at mimimum travel

At a bit of a loss. I have noticed that in daylight, the mirrors are perfectly lined up, so will have ot do a collimation next week.

Off to melbourne tomorrow morning to get pissed and fall over. But taking my Dell laptop to keep up with all the news

[ving]

see above...

[davidpretorius]

yes, lens out of the webcam , eyepiece out of focuser, adapter into webcam, and inserted into focuser

[ving]

oh, ok then :(
nfi what the problem is then...

[cahullian]

Nice one Dave
Wait until you see omega centuri and Saturns rings lol

[asimov]

quote:
'As you can see by the infamous "one night in mars" video i shot, i am at the minimum travel of the focuser late in the video, but still not at focus' unquote

By that statement Dave, I've got the impression that 'minimum' focus means your IN as far as you can go????? If that's the case....your in a spot of bother? If you mean the focuser is racked OUT as far as you can go, it's a temporary set back.

According to your mars video, the collimation is out by just a smidgin. But that could be a false indication, considering mars was not central.

Just re-read your report again. ok, your meaning your in as far as you can go but need to go further in to get to focus. Gonna go do a search on that & see what I can come up with.

[asimov]

http://www.cloudynights.com/ubbthreads/showflat.php/Cat/0/Number/31232/page/0/view/collapsed/sb/5/o/all/fpart/3/vc/1

It's a fairly long read, but it may be of use to you.

[asimov]

Found the prob Dave! Just read where a guy had the exact same trouble as you. He used the barlow with it & everything was fine!

[davidpretorius]

may have found the problem, (thanks asimov, i have quickly some of the link and this sounds very similiar as i can't turn my focus in any further ).

The switch on the modified toucam sticks out a fairly long way, so when you put it along with its adapter into the focuser, the switch hits the focuser.

So having now cut this switch to 1/4 of its length with a pair of pliers and reinserted it, i have focus.

Unfortunately the clouds came in as I was starting to take shots, but got some star video of achernar

From reading asimov's link, a barlow may help, but i am going to be taking the switch off the front of the toucam and moving it somwhere to the back

[asimov]

That's a crazy place to put that switch, don't you think?

Hmmmm. That would void it's warranty?? Moving it yourself?

[asimov]

"Changed the adapter on the camera to a 1.25" nose so that it slots into the barlow.
Put the whole lot on the scope and focus is spot on in the middle of the focuser travel.

Thank you very much"
-----------------------------------------------------------------------------

" typically the barlow lens is inserted into the focuser sleeve first.
In addition to amplifying the image 2X with a given eyepiece it also increases the focal length of the telescope ( that's actually how it works) and moves the focal plane back a little in the process. "

[davidpretorius]

thanks asimov, much appreciated. hmmmm guess who may have to speed up getting his orion shorty barlow?????.

I notice mick uses his barlow most times with his toucam.

I think three things to be done
1. collimation
2. move switch
3. get barlow.

all three things should sort it out.

By the way, i found an old trolley, which is basically 4 castors with a 1 1/2 foot x 1 1/2 foot piece of flat steel on it. It has been at my parents work for 20 + years. Beautifully fits the bottom of the dob!!! no more carrying, just pushing.