NEQ6 - First light + CCD/DSLR experiment #1

[Uranium235]

Since first starting out astronomy/astrophotography the only mount I had used until now was the CG5-GT, which until a few months ago had satisfied my thirst for the dark art of imaging since 2010. That was until I went to SGL7 and actually saw what these Skywatcher mounts had to offer. Initially, the only thing that put me off was polar alignment as I’m not a fan of getting my knees dirty by looking through a polar scope.

However, once the new beta firmware became available (which included a PA routine in the handset), I once again became very interested in upgrading. Though it was not purely because of that as I’d had enough of wasting (very) valuable clear sky to dec backlash and dodgy guiding, I also felt I was being held back in terms of payload as I would prefer have the flexibility of having multiple scopes/cameras working in unison, rather than explore the minefield of fast optics. Hence my decision to snap up a hardly used NEQ6 from ABS.

Nothing will prepare you for the weight of an NEQ6 – it makes the CG5 feel like a feather! By the time I’d mounted the OTAs I had quite a sweat on, which might prove useful in winter. But as far as carrying the mount + tripod at the same time down a steep flight of wooden steps to the patio is concerned, that’s not going to happen (would be v dangerous in the winter) so I will have to take it down in bits.

Additionally, when setting up it’s a good idea not to have the tripod above waist height (depending on how tall you are) otherwise, when you come to mount a cumbersome setup that weighs in excess of 10kg – you’re going to struggle a bit because the saddle will be at chest height.

Right, all cables hooked up both OTAs aligned and both cameras ready to go... Fired it up and entered the details required to begin alignment, choosing a 3 star alignment (not many stars to choose from though). Once aligned, the first task was to test the new software polar alignment routine that seemed very familiar to the one offered by Celestron mounts. And indeed that turned out to be true, exactly the same procedure and produced an alignment good enough for perfect guiding straight off the bat. The only thing I didn’t like about the PA was the altitude adjustment bolts, its hard work using those – and after hearing the horror stories about bent bolts I think they should be swapped out asap.

After calibrating PHD (thanks to Andy for the settings) I sat there staring at PHD for a bit waiting for backlash that never came, I was blown away.... absolutely rock-solid. At one point I forgot to stop PHD before removing the dew shield and popping on the b-mask – but PHD hardly flinched.

Being the day before the longest day of the year, it was getting pretty late by then so I decided to do a quick 30min run on the veil in luminance with the 1000d snapping the colour through the 150P, no serious work as it was just to see if I can get the holy grail of round stars.... yep.. all round, right to the corners, sweet! All that’s missing now is another 285 based CCD and another ED80, which would allow for 15 or 20 minute subs at double the rate, instant colour (using bicolour technique), faster mosaics, or speeding up narrowband imaging (especially in SII).

Roll on autumn/winter!

Loaded with everything ive got: ED80, 150P, 314L+, FW, 1000d, reducer, mpcc, finderguider, 500g counterweight (on ED80). Total weight, roughly 11.5kg.

Just half an hour on the Veil in 5min subs, with registar used to register the DSLR colour against the CCD luminence. Just testing so no calibration used (for either camera) and no major effort, the only problem was the awful off-axis halo in the 150P data, which is something I got when I used the 314 with it too - so that needs looking at or changing (I suspect its a secondary mirror issue). But, it didnt show through on the final version as i was able to clone brush it out on the RGB layer, however the red parts of the diffraction spikes on 52Cyg from the 150P remain. Which is a small price to pay for mixing two sets of data from different telescope designs. If id done this all on the 314 I doubt I would have gotten the full set in just 30min (I wouldnt even get two of each channel!).

[ncjunk]

That´s a very nice veil for the number of subs and looks like the set-up works perfectly...good luck and hope you get some more!

[Uranium235]

Thanks Neil,

Im hoping to put it through its paces over the coming months of increasing darkness, I just need to get that 150P halo fixed. It wont be as bad for targets where there are no really bright stars in the fov, but it would look rather nasty on something like M45. Im just wondering whether its becuase the secondary isnt properly central to the focuser, but that just means messing with it yet again with no certainty of fixing it until Ive tested it under the stars (only to find it hasnt gone away!).

Rob

[steppenwolf]

Excellent, an interesting project with good early results too.