ollypenrice

For me, a £500 budget for a refractor to look through would be second hand without a doubt. I'd want 4 inches minimum and a semi-apo spec. Olly

Nice to see all of it! Olly

That's a really interesting one with similar irregularities on the right hand side. Olly

Good capture but I agree with Alan on the colour. Are you absolutely sure you have the right debayer pattern in play? Olly

You've done a great job on the colour, bringing out the bluer, OIII-rich regions and distinguishing them from the more Ha-dominated parts. That's a lovely image. Olly

Lots of very old galaxies there! Nice. Why shoot Ha on this? Most of the galaxies are ellipticals so have no star-forming regions and I'd have thought the spirals would be too small to allow such regions to be resolved at this FL? Did you find it added much? Olly

It's a great result. The sharpening, though hard, didn't offend me and my only thought concerns the colour of the flame, which is rather reddder than in most renditions. My OSC cameras have always given it a kind of yellow-orange colour but I guess this is the filter at work? Olly

I'm going to argue firmly against printing services. Astrophotos are highly stretched and at the extremes of dynamic range. A calibrated screen does not, in my experience, give a predictable print outcome. It may or it may not. With your own printer you can make small test prints and adjust them before running a big one. I bought my own printer after print service disappointments. For photo printing in any quantity only an ink tank printer makes sense. Cartridges are financial madness. So... I use an Epsom ET15000. I'm very, very pleased with it and, as an astrophotographer, I'm a fussy so-and-so. I did wonder whether a 4 ink printer would cut it but, to my eye, it does. I'm also more than happy with the quality of regular photos - macro, landscapes, portraits, etc. I'm a far less observant critic of regular photos than of astrophotos, however. Once you've bought a printer like this, printing costs are trivial. Olly

Lovely job, Dave. Nicely balanced processing which makes me think mine was shouting a bit! lly

It becomes a shape when looked at.

My objections don't appeal to the standard model in any way whatever. I'm not trying to protect it, I simply want to know what makes a shape a structure. Olly

I don't understand why living in a first floor apartment means that power is a no go.. You can just use a power pack as many do. Olly

Good call. Olly

With a small chip like this you won't have anything like as much trouble with tilt as you can expect with an APSc. You're working within the comfort zone of the image circle. As for sucking in the photons - you bet. 3 hours with the RASA is a long exposure time. While my Avalon is out of commission our RASA rig is doing fine on a very well-used 12 year-old EQ6, too. You are in for some fun, I think. Olly

Never forget that Henri Cartier-Bresson said, 'Sharpness is a bourgeois concept!' It's a quality seen more frequently in pictures than in reality, too. We are all tempted to over-do it. I think it essential to test each each iteration of sharpening against the original by importing both into a program offering layers, so you can blink the sharpened version on and off, vary the opacity so you can have some, rather than all, of the sharpening and you can erase it entirely in parts where it is not a benefit. Olly

I confess to posting this earlier as B32, in a croped form. My processing was a total bungle from start to finish. Here I post it under a new identitity with grovelling apologies to Paul Kummer who did capture and stacking. Edit. Link to larger one: https://ollypenrice.smugmug.com/Other/Emission-Nebulae/i-d4KDgCR/A 😬lly

I cannot imagine imaging without a permanent observatory. Hats off to those who do - and I really mean that. Olly

Great results. The RASA isn't overkill at all. You could push significantly harder for the faint stuff if the mood took you. It's in there. Olly

Seconded! lly

What factors make this ring a structure? So far as I can see, it's considered a structure because it takes the form of a spiral. But does a shape equate to a structure? I'd have thought that, to be regarded as a structure, an object needs more than shape: its shape needs to be the consequence of coherent forces at work, forces which would produce this shape and no other. The components of a structure, unlike a shape, need to be united by a common experience or common history. Is there any evidence of this corkscrew's having been created by, or being sustained by, any forces in common? If not, I'd be more inclined to consider it a shape than a structure. I'd certainly consider it to constitute circumstantial evidence in favour structure but, until some uniting force were revealed, it would just remain a chance shape for me. (I once had the pleasure of attending a course and workshop run by Dr Roger Clowes at UCLAN. He was most entertaining and most impressive.) Olly

That's great, particularly in Ha which shows the connections so well. Gettng started on Samyang 135 mosaics is always a risky undertaking! https://ollypenrice.smugmug.com/Other/Emission-Nebulae/i-TqBkb24/A Your Sh2-284 looks lovely. Another one for the RASA... Olly

South is correct. I tried to match the hues from each source and would say that the Sharpless objects are a tad brighter than in nature. Then again, the Rosette here had a near-infinite amount of data and I stretched the blazes out of it. Olly

This is a situation in which 'stacking the stacks' can be better than stacking in one go. Make two stacks, one from each orientation, then co-register one to the other, crop the edges of the co-registered image and then stack it with the base image. Whenever you combine images it is vital to edge crop them because edges always have artifacts. Olly

Now that I've finally spotted this as a framing, I find myself wondering why it's not an established imaging classic. I've always felt the obvious extension was to the north and the Cone region rather than south to these. I suspect Paul Kummer and I will try this one properly at some time, using the RASA. For now this is a small doodle based on a Samyang 135 base image overlaid by an old Tak FSQ HaLRGB Rosette and RASA Sh2-280 and 282 in OSC. We'd actually need two more RASA panels to fill in the little bits that are missing. Samyang and RASA data captured and pre-procesed by Paul Kummer. Olly

One of the most attractive objects in the sky and done beautifully. It's easy to make nebulae look falsely solid but this is truly gaseous and ghostly. Olly