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frustrated!!! (getting to grips with a 6" Newtonian)
Posted: Fri Mar 02, 2012 6:05 pm
Last night i managed to get out for approx 2hrs with the scope. I attempted to get my newly acquired polar scope & RA motor-drive assy on & working so i could have an enhanced viewing session (not much light pollution at all from my back garden - back onto a school playing field). By the time i got the motor fitted (it fits quite well Ross - unless I'm doing something obviously wrong!!!) it was dark enough that i couldn't make anything out through the polar scope - so i had to revert to 'bore-sighting' polaris through the aperture of the polar scope & a laser pointer to guide me onto target!!!
Once there, i thought that i would simply engage the motor drive & it would hold polaris in the eyepiece... Sadly not. No matter what i did, the motor drive moved the scope not a jot!
So, undeterred, i carried on having a great viewing session. I realise that i can't make much out at all, i have a barlow x2 lens, a 25mm & 10mm wide angle eyepieces. I can just make out the concentric bands on jupiter, but any other planet is a bright blob, i managed to make out (what i call) the 'gaseous' nebulae cloud around horse head & flame nebulae (M42 & M43????) in the scabbard of Orion.
What eyepieces would enhance my viewing experience??? Can you guys recommend me some (that won't break the bank!!!).
Posted: Fri Mar 02, 2012 6:35 pm
We have all had frustrating nights! It is always best to trial everything during daylight - darkness makes it much much harder. Can you see anything through the polar scope in daylight? Is it in focus? Sometimes the reticule can be difficult but Polaris should be obvious. It can be quite difficult though to get Polaris in the field of view. Set the angle correct first and it should appear with a bit of sideways movement. As regards the motors. Did the light come on? Could you hear them - if they are stuck I would guess you would hear a buzz.
I wouldn't worry about a better eyepiece until all your other problems are sorted.
Don't give up - you can always bring the scope in next meeting for a health check!
Posted: Sat Mar 03, 2012 8:20 am
Yes, As Dave says, most of these set-up problems are best tackled indoors in daylight.
To that end, we're planning a series of "tutorial" sessions over the next few months - details to be announced soon!
Posted: Sat Mar 03, 2012 10:56 pm
thanks to you both for the advice. If i removed the polar scope i could see through it perfectly, i just couldn't make anything out through it in-situ.
The lights come on & you can hear the motor turn I've even tried the fine motor speed control - again to no avail.
I can't wait for the tutorial sessions planned, as all i can manage at the moment is to find my targets by 'bore-sighting' the scope & walking it onto target using a laser pointer. Not ideal & bad practice i guess as it would infuriate other observers - so its a crutch I'm going to have to ween myself off & pretty quickly!!!
Posted: Sun Mar 04, 2012 6:21 pm
Just like to say many thanks to Ross for taking the time to sort me out today - skies are darkening & cloud is almost non-existent, so hopefully, should be able to get some great viewing done...
Will report on the success/failures on Tuesday!
From frustrated to sorted in an hour?
Posted: Sun Mar 04, 2012 7:00 pm
Andy and I spent an hour working through his kit this afternoon, after which it should be all systems go..
First, we fitted the brand-new polarscope (the "posh" type where the reticule shows the relative constellation positons as a guide to setting the Polaris alignment-bubble) in his EQ3-2 mount: this was easy once we realised that we needed to unscrew and replace the complete original hour-angle bezel assembly:
Then we aligned the scope with the axis by rotating it in RA whilst sighting on a distant treetop.
Next we fitted the RA motor (the "economy" model without any slow-motion controls) and worked out that it needed to be switched to the "S" position to rotate the axis in the correct direction.
Then we tweaked the collimation (of the 6" Newtonian) using the BAS "Cheshire" eyepiece (http://www.boltonastro.org.uk/forums/vi ... f=17&t=112
And finally we installed the 6x30 finderscope and aligned it with the main optical axis.
This was all straightforward stuff (so no cursing needed
), apart for needing a selection of both Metric and Imperial Allen-keys for the various adjustments!
We also found that the 1.25" eyepiece-holder unscrews to reveal a T-thread, so he'll be getting an adaptor for focal-plane imaging with his Canon
Posted: Mon Mar 05, 2012 7:41 pm
I also have a motorised EQ3-2. I set mine to "N" (northern hemisphere). It seems strange that you need to set yours to "S".
The polar scope does have quite a narrow field of view. Under light polluted skies, it is easy to point it at an empty part of the sky. However, once the latitude is set, you will only need to make minor adjustments. Since Polaris is one of the first stars to appear in that direction, I always try to set up the mount before it goes completely dark then I have less chance of lining up on the wrong star.
Re: frustrated - not any more! (another satisfied customer)
Posted: Mon Mar 05, 2012 11:10 pm
A report on Sunday night's success received in email from Andy:
In a nutshell - absolute success!!!
I got the rig polar aligned - or close enough. I tested it on M42/M43 & used the fine motor control to keep the object on target. I also had to make a couple of adjustments to the finderscope as it seems to go out of kilter quite easily. So all in all, a fantastic evening's viewing! I managed to be out from approx 7pm until 11.30 which was amazing.
Cant wait to start a bit of imaging when i get the T adaptor (probably tomorrow now).
Posted: Fri Mar 09, 2012 1:37 pm
T Adaptor arrived yesterday (minus the allen key!!!) so ive rectified that by buying both metric & imperial sets. So hopefully (cloud cover willing) i will be able to at the very least stick my EOS 1100D directly into the eyepiece.
Or have i grossly miscalculated what i need to do to start snapping away????
Ideally, im going to try to snap the moon & see how it comes out. I know i need to set it to macro or something???
Cheers & will report back (hopefully with a piccy or 2!)
Posted: Fri Mar 09, 2012 4:41 pm
With your Canon the telescope becomes a large telephoto lens. So you don't use an eyepiece - your camera body connects direct to your focuser. You might get a bit of vignetting with that 1.25 inch adapter - 2 inch ones are better but would require a larger focuser. The critical issue will be whether the camera can reach focus ie get in far enough as the camera is roughly 2 inches thick and the telescope focus has to reach almost to the back of it.
You are right start with the Moon and ideally use mirror lock-up. Good luck!