Stub Mandrel

Craig Stark's famous pdf goes into more detail - he suggests you work out what is the limit on your resolution (seeing or aperture) and what that limit is, then select a pixel size of roughly half that. I'd guess teh AS178 is very well matched to the 130PD-s under our wonderful British skies Out of interest - where did you take that image of Bodes?

Presumably if your scope oversamples, then you may as well bin to get a better signal:noise, if it undersamples (130P-DS with a DSLR, say) just live with it or fit a barlow :-) My recent moon shots were with a 150mm scope, theoretically about 0.75" resolution, but 0.25" per pixel - in theory about 0.35" would be ideal (nyquist theorem - sampling should be at twice the frequency of the highest frequency you want to record - applies to spatial frequency of an image as well as sound*). 0.75" equates to a resolution of 1.5km on the moon but in practice I seem to have got features down to under 1km after stacking. Even though it's technically oversampled, the shapes of craters and mountains etc. are smooth down to the pixel level. Although oversampling may not give any extra image information, it does improve the appearance of the image, just as 'oversampling DACs' give a more pleasant sound. *To explain this in more detail - to record a 20KHz signal you need a 40KHz sample rate to record the high and low parts of the signal. Equally if Raleigh says you can resolve two stars 1" apart, you need three pixels spaced at 0.5" to record the darker zone between them, or four pixels spread over 2" to be able to always record the stars as two points.

Keep trying and you'll soon get the hang of it Bodes well for the future...

Yep, nice one

I've spent ages tuning my monitor and setting everything to the same colour profile, so at least my own images are consistent between applications. I still worry that my images look awful on other people's monitors... If you and @SteveNickolls see the same image differently it could well be because you are using different colour profiles, even if both monitors are perfectly adjusted. FWIW I can barely see a fuzzy dot at the middle of the pinwheel, but it leaps out if I do a stretch on the data.

Things did get a bit better and I had an inspired idea! Fit a bahtinov mask... you need a longer exposure but with a bright star yo can use the ADC to bend the bahtinov 'cross' like a banana. I found I could use Io with about two seconds exposure and get a very obvious shape, I then used trial and error to get it as straight as possible. Not 100% sure how much this is just getting eh orientation right and how much it is actually getting the setting right... In the end I ran out of sky and couldn't face moving the scope a third time at 1:00am

This is ZWO's manual. ADC Manual EN.pdf

Not sure it will make any difference - jupiter is bouncing round like a bunny - the seeing is appalling. Perhaps it will be better when it gets up to 20 degrees

I was going to set it using the IR cut only setting to get 'maximum blurring'. Google says you can get a filter that lets through red and blue (magenta coloured I suppose) so you point it at a nearby star that 'splits in two' and you adjust the ADC until it is a single point.

I glued a tiny square of printed circuit board material on as a stop.

Last night: I accidentally did M95 and M96 instead of the triplet... lots of duff subs due to losing the faint guide star. I have changed my workflow a lot, and combined with temperature matched flats I seem to be getting much less noise and much better star colour, although I could do with finding a nice colourful target and darker skies.

Apparently it still sharpens each channel quite a bit.

OK, I've set up my 150PL with a five position filter wheel (IR cut, IR&UV cut, Blue, Green, Red), then ADC, then x3 barlow then mono camera ready for Jupiter. Great! Epic! But... how do I get the ADC set properly using a mono camera? All I can think of is selecting blue then trying to get the image as sharp as possible? <edit> should add I've been practising on aldebaran setting up finderscope, practising focus, get to know camera controls etc.

Last night's Martkarian's Chain. 90% of 3 hours 30 minutes of 5-minute subs.

All they need now is a vibration-proof webcam on the drone ship!

Launch OK and first stage landed on OCISLY

Broadcast in the 'trance music' stage...

Thirty second launch window in 112 minutes. Need to time my battery change right :-)

How far you can see towards the horizon rather than straight up (i.e. it gets reduced by fog, haze, snow or rain).

Unfair! I'm boycotting Norfolk and Kent...

With any luck I'll finally be outside imaging! At least it's a couple of hours earlier in the evening...

I think it was always planned for today?

LOL! SpaceX have 'transparent Pricing' http://www.spacex.com/about/capabilities Think about how hard it is to get a firm price for some very simple things - yet you can just look up the cost of a satellite launch...

Oh dear. Bad Tie. ... Now Autocue Alert - I didn't know they worked outdoors... "On Time and On Schedule... and On Script"

In its defence MEPC does dare to state that you can do AP with an EQ3.