Whistlin Bob

Great project, and love the quote! I have a 14” (manufactured, and nowhere near as beautiful as I suspect yours will be) and it is indeed full of stars. 

Finally got a finished version of last Saturdays subs. I managed to collect 16 ten minute Ha subs (it was a bright moon), along with another 10 of the shed wall (not included here!). I used them for the B&W image below, then combined them into the red channel of an RGB image from 9th October on the same target. My framing was a bit different this time (I definitely need to improve my framing), so the colour image below is the intersection between the 2.

130pds, Canon 600d, HEQ5, Baader Ha Filter (Ha), IDAS D2 filter for RGB from October.

1 hour ago, Uranium235 said:

would require a smaller central obstruction and secondary mirror size

So presumably a smaller illuminated field? I wondered if it might be something like that. Perhaps one day I'll get a short f/l frac instead- but I'm sure the 130pds will keep me going for a long time to come, before further investment is needed!

1 hour ago, Stub Mandrel said:

So assuming you focus perfectly in the middle of that zone, a temperature change of just  over 6 degrees will put you out (just) of focus.

I suspect the number of nights where this occurs is quite small. It's a good thing to be aware of, but unless there's a change approaching that, then I'm going to carry on hanging out in the single focus club! ?

I've not had too many problems with the focuser and mine seems to hold collimation pretty well- I check it most sessions and it's usually fine.

The thing I've always thought would be good was a shorter focal length f5 newt to go into the pds range, for a wider angle, so you can really go after some of those giant nebulas like the veil and the California. Wouldn't need to think so much about full frame then. I'd be more than happy to pay a similar price for that.

Sorry if this is getting off topic...

Here's another M33. On SW 130pds, HEQ5 and Canon 600d with IDAS D2 Filter.

50x5 min subs + flats, dark and bias.

Still a bit noisy, but very pleased with it.

Thought perhaps it's time my 130pds made it's contribution to the thread that caused its purchase...

Taken on 28/29 October:

Image: 17x539s Subs in Halpha (Baader 7nm) , 21x 300s subs in RGB, + flats, darks & bias.  Stacked in DSS, Processed in Pixinsight.

Kit: 130pds, HEQ5, Canon 600d (modified) , SW Coma Corrector, ZWO 224 on Finder/Guider using PHD2

Oooh- I saw that one. Very exciting! Nothing like spontaneity! ?

The HEQ5 copes fine with my 8 inch, so you might be lucky- although the tube rings may cost more than the scope...