Paul M

I've been playing with the latest ASTAP version again. I've got it going after selecting "ignore existing FITS header solution for astrometric stacking" in "Alignment" Tab. This version auto arranges the frames without specifying how many rows it contains.

It's a while since I used it but here is the method given in the ASTAP user guide:http://www.hnsky.org/astap.htm So, I'll do it again with the original stacked frames linked in my first post in this thread. See how I do! Here are my 6 stacked frames (all calibration done in the stacking of each frame, don't apply flats, darks etc for this stage). Just load them in the "lights" tab and make sure they are all selected. Click analyse and it should look something like this: In the "Alignment" tab select "Astrometric Alignment". Most of the other settings on that page are defaults for what we are doing now, but can look intimidating. In the Stack Method" tab select "Image Stitching Mode", and here I've opted to Equalise Background, Merge Overlapping Backgrounds. My mosaic is 2 rows high (the latest version of ASTAP does that automatically but I've had trouble with that development version just now), The 6% auto crop is just a number I liked the look of... Then select "Stack (image stitching mode)" After a while my modest lappy gave this: Which can be cropped by Right Clicking at one corner of the image and dragging out a crop box. Select Crop and hey presto, I have a whole world of gradients. The gradients are my problem not ASTAPS. The very latest version has a box to reduce overcorrection of gradients. But as above, that version wouldn't produce a mosaic on this occasion. Good Luck.

It does indeed, but my gradients beat it! Even Han, the developer of ASTAP, couldn't fix my gradients. But that's Blackpool Illuminations for ya!

That's pretty much how ASTAP does it too, for free!!

If you hit any snags just post here, I might be able to help. I found building a mosaic to be very satisfying. I know, I could have done a much better job of the pleiades by using a suitable instrument but where is the fun in trudging down a well trodden path?😁 And the clouds and light summer nights don't stop us playing with software.

I've used ASTAP for mosaic stitching. It worked very well although my individual panels had such strong gradients the final image was a bit pants! Here is a post I made midway through a topic I'd started. The ASTAP user guide gives details. It's just a case of making sure the right settings have been selected. Stack method tab, Image stiching method (Mosaic) Astrometric image stiching is possible with the internal astrometric solver. The reference of each pixel is the astronomical position. So stacking is not done against a reference image but against an position array set by the first image. You have to set the in tab alignment the settings for "Image stiching (method)" correctly. If you stitch 4 images, you have set "Mosaic width/height in tiles:" at 2. This will provide enough space to place for the 2x2 mosaic. Here a suggested work method: Stack the tiles separately using method "SIGMA-CLIP-average" and use for the alignment the internal STAR alignment method. Inspect the resulting tiles and crop them if required. You can also crop them later automatically with "Mosaic skip outside pixels" Do this for each color separately if you have separate files. In tab "stack method" select option "IMAGE STICHING METHOD" and select astrometic alignment using either the internal solver. In tab "stack method", set the "mosaic width/height" correct and check-mark the option "equalise background". If the input images have poor borders, set option crop images larger then 0%. Select the files. Most likely the files names contain "_stacked, so you have the check-mark the files after selection. Click on the button Stack check marked images| Crop the stacked result using the image crop option in the viewer mouse pop-up menu. Adjusted the stretch range and save as JPEG, 90% quality. Here an example mosaic x 4 of M31 made with ASTAP: http://www.hnsky.org/astap_mosaic%20x%204.jpg Here an example of a mosaic build of DSS images: http://www.hnsky.org/astap_mosaic.png The size can be reduced by a crop function (right mouse button) later. Making the oversize too large could result in memory overload. If you have DSLR/OSC sensor and using a monochrome filter like H-alpha, you can split the raw the images in seperate R, G, G, B image using the viewer Tools, Batch processing, Raw colour seperation menu. In case of H-alpha use only the R=red image for future processing.

I was just reading up on those and although I'm not on the market for anything in that price range, the spec impressed me. It's got a good weight capacity, but I continue to struggle with the idea of such a low mass fully controlling a big old rig. My main stumbling block, if I were on the market, is the integrated computer. It sounds expensive to repair or replace. Maybe back to a piggy-back mini PC if it dies outside the warranty period? But no, probably no external access to the motor control boards, even if they are separate from the computer board. Perhaps it's one of the growing number of ARM based SBC's that are commercially available, but my gut instinct is that it will be sufficiently custom that it's not so easy.

Very nice indeed. At the scale shown on my laptop the stars look fine, natural even. Indeed the whole image is very easy on the eye. I find myself flicking past an ever increasing number of AI enhanced images that are too "jolting" for my taste!

I had a look at 04:30 yesterday morning from a high vantage point at my work site but found Venus to be a faint red spot. Just to confirm the negative result, I scanned the area with my ickle 8 x 40's but couldn't find a single star in the sickle so that was that. Probably my one and only atempt.

As an aside, tonight might well be my one and only atempt at spotting this. Providing the sky stays clear. Unfortunately it's forecast to devolop a high cirrus overcast towards dawn

I'll try to keep to bullet points. I just added myself using this. Configuration Window Plugins Solar System Editor Configure Solar system > Import Orbital Elements in MPC Format. Online search Enter C/2023 P1 in search window - it will then show this: Tick the box and "add object" Done!

It wasn't ISS going off this: https://spotthestation.nasa.gov/sightings/view.cfm?country=United_Kingdom&region=England&city=London ISS is currently culminating in the early mornings. There will be plenty of candidates with 2 large solar arrays, but it would need you precise loaction and a bit of work and even then, if it's a military sat then it might not be very well advertised! Whatever it was, it was a very impressive capture! Excellent!

It seems to be the case that whenever a reseach group takes on General and/or Special Realtivity hoping/expecting to "break" them, they end up by proving those theories to ever closer tolerances! Is it time to accept that the Relativities are, for all intents and porposes, no longer a theory? How much more proof is needed? At what point does a theory become fact? And, while we are here, how/why is Darwin's Evolution of the species still a "theory"? I mean c'mon!!!!

Quite a spectacular Moonrise here at our Luxury Cumbrian Villa. Unfortunately I only had my phone camera to hand, which doesn't really lend itself to lunar photography.

That's impressive. I rember Shoemaker Levi leaving a dark, oersistant "scar" at the site of the individual impacts. I'd expect something similar this time.

The late and arguably great, Sir Fred Hoyle, coined the phrase "Big Bang" dismissively* But could "it" have been named any better? Entries on a postcard... 🤣 * I really liked the Steady State theory as a boy, and at the rate that science was disseminated to the masses by books back then, it was still seriously considered. No scientific evidence on my part, it just upset me less than the idea of a "beginning".

Here it is as displayed in HNSKY, between the yellow markers in Gemini, Low in the ENE at 4 am tomorrow. Doable, with a good sky and horizon. It's just about 10 deg altitude from my location at that time.

I rarely use eyepieces now, for a few reasons not entirely related to having the imaging bug. Eyesight showing its age. Bad back and stiff neck make sitting at an eyepiece a chore quite often... The Douglas Adams quote, above, reminds me of something I've mentioned a few times before; that some things should be experienced and not just recorded. A case in point being the two total solar eclipses I've had the privilege of experiencing. It is a multisensory experience that no image or video will ever capture. The change in the quality of the light, long before totality. The gradual drop in temperature. The rushing of the umbral shadow over the horizon. The silence of totality. And the visual appearance of the corona, like nothing else you will ever experience. My second eclipse was the 2006 total eclipse, who's central track we intercepted near the resort of Side in Turkey. Our hotel was the base for many eclipse chasers and when we wandered down to the beach (in our speedos) before totality we saw a large group on a Sky & Telescope eclipse tour. Tons of gear set up and they in their overcoats and hats. Sure they saw an eclipse but how much did they miss? I think that if you come from a position of looking up and wondering about the night sky then you'll likely pass through a period of visual telescope use. I guess that might be the case for a long while yet. Having a dark site helps a lot but the planets offer so much to visual observers that they alone are worth retaining a visual set up., as I do at our dark(er) sky get-a-away in Cumbria.

Whilst it's a truly exquisite image . It's a bit of overkill just to capture nova V1405, which is still hanging on in there in Cassiopeia! Well, once a star hop and assiciated asterisms are burnt into your minds eye, there's no escaping it... 😁

It's been very clear here all day. The view accross Morecambe Bay to the Lakland Fells was stunning. So I wasn't surprised to see the peaks of the Isle Of Man this evening while walking the dogs. And for added interest, I arrived on the seafront just a couple of minutes before sunset. I did wonder if the slusive "Green Flash" would be vivible. I just had time to get my phone camera set. Visually the Green Flash was quite clear but it's less defined in my video. The camera was hand held, I had two insane Labradoodles trying to drag me down to the beach and I wasn't really watching the screen, I was watching the sunset. So it's a bit drifty. I'm assuming that the larger of the Manx humps is Snaefell and the sun sets just to it's left flank. 20230816_204026.mp4

I've always held the belief that, so far as the general public and national press are concerned, the Perseid's are over hyped. In my own lifelong stargazing career, I've only had one positive experience with this shower. It was circa 2001/2002 and I was on a Scuba Diving trip to Oban during the Perseid's peak. As with all proper Scuba Diving trips, you dive in the day and drink all evening... So my Buddy and I got back to our digs after lights out (oops!) and eventually got to our room. I was mindful of the meteor shower so hung out of the bedroom window to have a look. Boy, it was a good sky! And I remember seeing a number of great meteors. Perhaps it was a good year? Good sky? Both? I probably saw more Perseid meteors in that one impromptu session than in all other years combined.

Climbed to the top of a silo at my work at about 3am. Good view overhead and to the easterly quadrant of sky. Still lots of industrial lighting but just about the best spot I could find at work. I looked for meteors for some time but failed. It's so long, a season nearly, since I looked up at a dark sky, that I took some time to get orientated. I mean, when did Jupiter get all the way back up there! I nearly put in a UFO report!🤣

I've only seen the green flash a couple of times in many years of looking but I guess there is about as much chance of capturing that as there is of capturing first contact of the eclipse!

I had a few looks in the early hours of today while working a night shift. Lots of cloud had moved in but there were big gaps here and there. Didn't see a thing. My work site is currently a huge construction zone. Temporary floodlights abound, so limited dark adaptation also. Hopefully there will be some big gaps in the clouds during tonight's shift. I've always been disappointed by the Perseid's. I'd say my success rate isn't much above the sporadic meteor rate!! Bring on the Gemenid's, a proper meteor shower

This bloke would have surely been a YouTuber....