Stub Mandrel

My guess is slightly different default settings? Spot the difference and you have found the cause and can correct it.

Good stuff, Galen, nice red Ha halo outside the blue.

I use a 6" F8 on an EQ3!

I hadn't seen this thread before, it's really useful.

Try reducing extruder temperature, also do you have a cooling fan on the extruder yet?

I was sure I had some images of that bit, but only at 135mm. this is the other bit with a modded 450D:

That's great for the amount of data! I thought it was red, I must go back and look at my subs again and see if I can get more out of it!

Works on my android and is mercifully ad-free (except for Aunty Flo of course!)

I haven't set it yet

Just studied my GOTO box code in detail. Discovered the 'guiding' routine I thought I'd have to remove and re-write is actually OK! I just have to figure out which button is which wire... but I'll be trying to break the EQ3 sub-length record soon

One zillion times easier with the new reticle, you set the cross-hairs vertical/horizontal, use Polarfinder to tell you where to put polaris on the circle and there's a crib in the corner telling you which diameter ring to use for the year. You can download a new-style reticle for polar finder here: http://www.stubmandrel.co.uk/astronomy/123-new-style-reticle-for-polarfinder My home made goto box displays the correct position:

I use AV mode at the same iso and it works very well. You will need to restack, but you may be able to reuse the flats if you don't suffer dust bunnies and have a consistent setup.

The new-style reticles are good for up to 120 seconds.

It's a faint object against a rich starfield.

Here you go Bob, 60-second subs, 65 of them.

Not getting brilliant results trying to image Ha on a DSLR with a sensor temperature of 29 degrees... but here's a 50% Ha lum with a standard DSLR image of the crescent from May. Interesting that Mikey seems to have got some OIII (the blue nebulosity):

Cosmic! Literally and figuratively!

Potentially much better than the Baader ones, but no doubt you need a second mortgage to buy a set!

Luck man!

No The gamut of a 'square curve' sensor is vastly smaller than that of a 'curved curve' one, even if its sensitivity to absolute luminosity is lower.

So far I just mixed it 50/50 with the 'synthetic' LUM

Initially I will revisit ha-rich targets, although I may have a go a the Eagle nebula or with my 135mm lens on the crescent.

First results with using Ha: The Ha stacked at 50% resolution using DSS super pixel mode, was very noisy (it was hot night!) so denoised in Astra which took out some of the fine detail. 60 1 minute subs and 30 2-minute subs. Mixed in a 50% lum with an ordinary DSLR image from last summer (but with different framing): The original image without Ha:

M57 responds really well to lots of subs + drizzling.

Good question indeed! I'd be intrigued to see how a CMYL sensor would perform (bear in mind that 'L' is essentially the inverse of 'K' - black). It would have sensitivity of (2+2+2+3)/12 per unit exposure = 3/4 compared to (3+3+3+3)/12 for a mono sensor - that's 3/4 the performance of mono! But then you can collect much more data as you don't need to do the RGB runs, plus you are collecting twice as much R and B data as with an RGGB sensor. I think it would knock both RGGB-type OSC and LRGB/mono into a cocked hat.