ollypenrice

This appeared just below the Rosette on our Samyang Orion-Monoceros mosaic so we had a closer look with the RASA. It looks like a smaller Flying Bat nebula - a Flying Pipistrelle, perhaps? Like Lower's Nebula, this is big, bright and rarely seen in boradband images. Too many famous neighbours, maybe? Capture and pre-processing, Paul Kummer/ My post processing. 120x3 min subs. To see it in context, here's the link to the mega-mosaic with these data blended in. https://ollypenrice.smugmug.com/Other/Emission-Nebulae/i-TqBkb24/A Olly

Really sweet. Maybe the first one for me? Olly

For me, yes, but some find it variable from image to image. I also had a lot of hassle getting Starnett to work at all and then Pixinsight imperiously deleted it from my PC, which got on my wick. On some images, usually large mosaics, StarX can leave a kind of checkerboard grid pattern latent in the image but that's the only downside. There are different ways to recombine the stars. I don't find one consistently better than the other: again it varies from image to image. I still regard StarX as the biggest technical advancement in AP (hardware or software) since I started fifteen years ago. Olly

We don't dither using a CMOS OSC on either of our rigs and I didn't dither with the CCD rigs either. They were dual rigs so it would have been complicated. Looking at your kit list, I'd only regard it as essential with the DSLR and there it really is essential. Olly

Crisp and nicely exposed. Olly

I remember having shaft-like out-of-shot flares affecting Tak FSQ images (F5) and ODK14 images (F6.8). I wouldn't be too sure that it had anything much to do with F ratio but I really don't know. With the RASA we do get arcs, on occasion, rather than 'shafts.' I just go for a cosmetic fix on the starless layer. So far so good... I don't regard stopping down as an option on either of our F2 systems. F2 is just too good to mess with! Olly

My big thing is processing: Star X and Noise X have changed the game. Blur X is good provided your star shapes are decent to begin with. It's the least important of the three but stretching an object without stretching the stars is bliss. Star X. You won't look back! Olly

That's very nice with lots of texture in the nebula. There's a distracting amount of green in the background along the lower quarter of the image and on the right hand side. This would be a very easy thing to avoid using Hasta La Vista Green or SCNR green in PI. Also an easy fix even on the finished image as we see it. That apart, that's a hell of a lot of image for 33 minutes!! I'm impressed. Olly

No, I'm afraid I never had this one. I had 7 Atiks but never this chip or the 8300. These artifacts don't bother me but if they do bother an imager they are a simple cosmetic fix in Ps. Olly

The classic wheelbarrow handles might work for you, then. https://www.google.com/search?q=dobsobnian+wheelbarrow+handles&rlz=1C1CHBF_enFR821FR821&oq=dobsobnian+wheelbarrow+handles&gs_lcrp=EgZjaHJvbWUyBggAEEUYOTIJCAEQIRgKGKAB0gEKMTE5MTFqMGoxNagCALACAA&sourceid=chrome&ie=UTF-8#vhid=aue2pqn7Umgm0M&vssid=l&ip=1 Olly

I think that's much nicer. Have you tried Russ Croman's Noise Xterminator? It is utterly astounding and miles ahead of any other NR routine I've tried. It probably came along while you were out of action and I think it would be ideal for this image. Olly

Yes, that's true. I do, quite often, selectively process a handful of bright stars which haven't responded well to the overall stretch. This is easy with the selection tools available in Ps but I don't know if PI has an equivalent. Olly

It seems that you can generate a star image, which I take to mean 'stars only.' That's what it gives me in Ps and that image can be manipulated in Curves before being finally applied over the background. Pulling down the bottom of the Curve more than the top will bring the fainter stars below the brightness of the background, so they become invisible. Olly

Indeed so! Olly

I've had flares from out-of-shot stars with various scopes. I can suggest two solutions, one more 'ethical' than the other. 1) You can make a patch panel by shooting a fairly short run of subs with the source star closer to the image centre but with enough overlap to cover the flare. You just use this patch to replace the flared bit on the original in Photoshop Layers or whatever. 2) If you use a star removal product, once you have a starless image it is dead easy to lasso the flare and use Content Aware Fill in Photoshop - provided there is nothing much going on under the flare. If it goes right through the middle of the Horsehead, this ain't gonna work! Olly

You need to tell us the kind of portability you need. Stairs? Transport by car? Just rolling it out from garage or shed? For the latter, a 20 inch is no problem once you're organized. 'Less than stellar' is the understatement of the year in my house. Anything more must be by PM. Olly

OK, I'm not so sure about the rationale behind using two palettes in the same image. I can certainly see the point if, like HOO, the palette closely resembles RGB but the Hubble is in flat contradiction with RGB. I'd be more inclined to combine RGB stars with HOO. I think this would look more consistent. Olly

Good! The stars across the field are really classy in the M45 shot. Olly

It largely depends on the target, surely? Some don't have much fine detail, some have lots. I'd call the California relatively low on small scale detail at shorter focal lengths. Since I remove and replace stars anyway, and give them an entirely different stretch from the subject, I find myself using the standard stars over the BlurX ones but I like BlurX on fine target detail. Olly

Do you use StarXterminator? It's a wonderful tool for controlling star size, and manipulating the Curve on the star-only layer does give control over fainter and brighter stars independently. I don't do this in PI but in Ps, but it ought t be the same. Olly

More than a tad, I think. Massively oversampled anywhere with those optics. I found 0.66"PP oversampled using a 14" ODK at a guide RMS of 0.3 arcsecs. What is your guide RMS in arcsecs, Ron? A good EQ6 runs about 0.5" and that will support an image scale of about 1"PP, so nowhere near 0.66"PP. Darks do need to be the same as lights but flats could be resampled upwards to their unbinned equivalent. I'd shoot new ones, though. Except that I'd stick with the binning... Olly

Another Olly (but with a 'y') here. Greetings. I've been using a RASA 8 for two years, now. It really is a scope from which there is no going back. No F2 system is going to be dead easy but the RASA is very remarkable in some key respects, most notably focus. Incredibly, it autofocuses easily and holds focus better, if anything, than the premium refractors I've used. Tilt is going to be an issue at F2 as well, but it is just as likely to come from the camera as from the scope. Patience in the early stages is all. A good dealer like FLO will give you chapter and verse on the bad batch of optics Celestron received from China. I haven't used a Hyperstar but have read many tales of woe regarding setup and I'm very rarely impressed by the stars in posted images, especially broadband. RASA stars are pretty good, especially using star removal and replacement in post processing. (I think almost anyone working at short focal lengths is going to want to use this method these days.) Personally I would not buy a Hyperstar but that's me. I also find their marketing blurbs borderline illegal and in contravention of advertising standards, which does annoy me. Sample RASA 8 images: https://www.astrobin.com/eolyxc/ https://www.astrobin.com/rwyqce/ https://www.astrobin.com/bubqfe/ https://www.astrobin.com/vlomu9/ Olly

Great choice of gear. Compact and potent. The new CMOS cooled cameras roundly beat CCDs, let alone the older DSLRs. At some point you might consider a dual or tri-band filter designed to work with one shot colour. I use the same camera plus another with the same chip and I recently had a couple of Redcats visit. They gave pinpoint stars across the chip. Very impressive. Olly

First a gentleman. And then a very fine telescope craftsman. I went to his home in Nottingham to discuss a possible order when I was setting up Les Granges twenty years ago. Sadly I had so many demands on my available funds at that time that I had to go for a lesser instrument, second hand. However, I still have a vivid recollection of his courtesy and gentle manner. He really did make an impression on me and I'm deeply saddened by this news. Condolences, of course, to his family. Olly

Very nice work indeed. The thing about a NB palette is that it allows far more distinction between OIII and Ha emission than is possible in natural colour. Paul did say it was known as Lower's nebula but I clean forgot. Can we tempt you to add a second panel in search of that southern loop? (Our version is N up.) Olly