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EQ3 Pro Unguided test shots...


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First clear skies since i had the mount ... hopefully i followed AB's tutorials correctly to setup the polar scope and use it to PA...

Although I have made a prototype autoguiding setup for it i decide that i would bnuild up slowly so tonight I have been doing increasingly long test shots wi the Mount just tracking at the Sidereal rate... No laptops etc just the hand controller skipping the alignment routines and just manually enabling the Tracking...

heres a couple of test shots roughly centered on Saturn - no processing to remove gradients etc as all I am interested in is tracking...

300s%2050mm%20f4%20unguided%20QS.jpg

600s%2050mm%20f4%20unguided%20QS.jpg

I'm "fairly" happy :D:p;)

Peter...

Edited by Psychobilly
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I think it might be...

That the setup i want to take to a couple of dark sky sites up inthe Black mountains to get some widefield shots later in the year if i can get results like taht without the added weight and complexity of the autoguiding rig and the netbook etc then it means i can go a bit further away from the Car..

I need to get a pack frame next...

Peter...

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Cheers John...

It makes the efforts (and expense) of the last few days seem worthwhile...

Obviously longer FL are going to put more demands on it but I am quite encouraged so far...

I cant wait for Cygnus to be better placed ... I would love to stay up for it tonight but an early start in the morning :D

The battery ran out in the middle of my 20 min test shot .. normally the cameras are run from adaptors so its not an issue .. just one of those things I forgot :p

Looks like I fluked a metor inthe first one HA isnt listign any Iridium flares at that time or in that direction......

Peter...

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Looking good, have you quantified the polar alignment error? Which lens is this? I was doing the same thing last night (but on EQ6 Syntrek) and my Takumar 55mm f/1.8 had to be stopped down to f/3.5 to give nice stars to the edge.

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No I havent..

I'm taking the that looks about right approach for the 50mm lens will have to see how it gets on at longer focal lengths .. the longest I am going to be using is 180mm ...

If i can get away with that unguided with 5 min subs I will be really happy...

Peter...

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Drift Rate Calculator

suggests that a one-arc-minute polar misalignment will result in a 5-minute drift of about 19 arc-seconds (at the celestial equator, declination 0).

19 arc-seconds covers one pixel (5.2 microns) with the 55mm lens. It would be only 6 arc-seconds per pixel with the 180mm.

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Thanks for the link :D

I have just been Playing with the 180mm - Its a Nikon Fit Sigma 180 f3.5 APO Macro with a Nikon-EOS Focus Confirmation Adaptor.. seeing as the lens has a manual aperture ring it works a treat with the canon in Av or Manual modes and has no problems with Infinity Focus...

Tried the 10-20mm Sigma as well cant see me being able to use that one at home though.

Peter...

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May I just ask, is it because you are using an ordinary lens at 50mm that you are able to get such long subs? I am yet to buy motors for my scope but even with pretty accurate polar aligning, I was under the impression that I would only be able to get in the region of 45 second subs. Or is that when you are imaging at prime focus?

With motors on my EQ5, and some more practice at polar aligning, am I likely to be able to get 300 seconds at 50mm too? Or is the EQ3 Pro a much better mount at tracking?

Thanks

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An accurately levelled tripod (in all direction) good PA and a mount with lower PE will all help..

The longer the focal length the more evident the effect of the numerous sources of error will be in the star images...

The 4 bolt arrangment on the pier makes leveling easy and in the end I used a level which is accurate to 0.5mm/m (about 0.025 of a degree) .. I spent some time making sure the polar scope was properly aligned to the mount (Astro Babys tutorials) and then made sure that the date circles etc were properly setup. I also made the adjustment for the fact that I am a few degrees west of Greenwich...

I took some time on the Polar alignment but only using the polarscope... and then I by-passed the star alignment routines in the handset and just enable the RA tracking at the Sidereal rate.

Its almost a case of anything close is better than nothing but the closer you can get it the better the results....

Peter...

Edited by Psychobilly
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Only the second tiem out with it tonight so another KISS night I ahve the autoguidign setup mounted up but only to co align the finder and the guidecam which i did on venus a bit earlier...

At the moment i just ahve the mount set to sidereal tracking again but this time I am using the Modded 1000D with a Nikon fit Sigma 180mm f3.5 APO Macro... infinity focus is a bit touchy as its a dedciated macro lens...

I used the B&S head to swing it round onto Arcturus and I am taking increasingly long test shots... Bit more breeze tonight and a few clouds as well so I don't think it will be a long night...

Getting some trailing at the longer FL "unguided" so will need to revisit the PA and think about drift aligning...

Helps if you remember to tighten up the Main mounting bolt -- doh...

So here's a 480s sub with the 180mm f3.5 unguided...

480s%20180mm%20f3-5%20unguided.jpg

Going to spend a few hours with the nifty 50 getting a few constellation shots...

Peter...

Edited by Psychobilly
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