João Calhau
@astrocalhau
The second rock from grandpa. Astronomy from Alentejo🇵🇹 to the World. Lancaster Uni alumnus. Post-doctoral researcher at INAF, Italy. Likes galaxy evolution, AGN,SFR, and Universe in general. Personal account; Opinions my own. astrocalhau.wordpress.com
Because the daytime temperatures are around 42ºC and the night time temperatures don't go below 28ºC, we basically can't sleep properly at night anyway, so I spent the night yesterday imaging the Veil nebula. Around 3 hours so far. (1/2)
I tried. The clouds didn't let me go too far. They weren't thick, just annoying enough not to allow guiding (though it did rain this morning so now we are in high heat AND humidity. Fun). Managed less than one hour of NGC5982 and friends. Not a good one - too noisy. 1/2
Also, the inner section of the Nebula, barely resolved by my small telescope. In order to see both clearly, I'd have to integrate for longer, get a longer focal length telescope, or separate the image in sections to process differently and then merge them back together (but that feels wrong to me).
So I did another 2h on it. It clearly needs much more integration time to really bring it out from the background, but it's such and amazing object. Really looks like an iris. Hopefully I can target it again in the coming months, as it rises earlier and earlier.
It is only two hours, as my sky is restricted to the eastern celestial hemisphere, due to the houses in my street so, past the meridian, it becomes obscured by my roof. I also did not use a filter, and I think it is the better choice: no haloes, even when I blow up the image to kingdom come.
Last night was the first clear night in the past month or so that I was able to catch (all others were either work days, or had full moon). So it was time for some photos. My sister had expressed disappointment that I had not captured the "one with the little one on the side", so I started with M51.
But is this due to the Frenchness of the emojis or simple variation of patterns? To check this, I have selected a pattern of distinct British emojis. No amount seems to trigger the Korean response. I also rechecked that the thumbs up emoji works on Windows. So it is not OS dependent.
I also did ~1h of M13. Here the processing wasn't as aggressive as it is only stars, anyways. But I pushed the saturation a lot and am happy to see the contrast between the older and colder red/yellow stars, and the younger blue stars. (3/5)
Had the opportunity to take some photos last night. I wanted to test the 6'' RC, which my Ragdoll 17 Pro should be able to carry without counterweights (it did). First, ~2h of M63, the sunflower galaxy: (1/5)
I reprocessed my M101. I am hoping to get my replacement focuser next week, for the RC6, and then can get higher magnification and detail on these objects. Tonight is supposed to be clear, but it is also Monday tomorrow. Maybe I can trick myself to not feel guilty by doing work during acquisition.
To close the night, I decided to go for M13. Only half an hour, so not a lot of stars yet, but still a nice target for small telescopes like mine. Looks absolutely stunning at higher apertures and focal lengths though, so I look forward to see it through my 150mm RC, once I get the new focuser (3/3)
Once the Pinwheel was high enough I started the integration. The good part of rain is that it clears and stabilises the atmosphere so the seeing was pretty good for my place. Once the target got high enough, guiding kept within <0.5''. In the end I got 3h of useful data (2/3)
Yesterday we got the first clear night in 2 months and since my life kind of sucks right now, I decided to make use of it to relax with some astrophotography. From the get go, the idea was to target a single target: M101. But I had to wait for it to get higher. So I burned 1h with M106 (1/3)
I couldn't find a quality gif of the leroy jenkins sequence, so I had to go with this. It may not be smart. But it is more satisfying.
Hey, I also targetted this one a while back! Interesting how the optics and the data "reduction" changes the colors! Though I have it "laying down" as my desktop background :-D
Had to throw away several images due to said clouds but 5 hours in and we're starting to get somewhere. A good rule of thumb in Astrophotography is (aside from tracking issues) there is few problems that more integration time does not solve (or, the Kerbal Space Program approach to problem solving).
Then I went to the true target of last night's session: adding more exposures to the Rosette Nebula, NGC2237. It is working well, this is now 3h of total integration and I would like to add more... But I won't because luck is real and it likes to laugh so it'll be cloudy till April. (3/5)
Using sigma clipping when stacking removes these (or helps). This is just 30 minutes of The Great Orion Nebula (the capitalisation is required), just for me to test the sigma clipping. It works, but I still do not like having to do it. (2/5)
The only night in the past month where I have been able to set up my gear and snap photos, between work and weather. Targetting M42, hoping against hope that I can get a few clean frames. It is impossible.
Worked until late yesterday, but the weather prediction announced clear, so I decided to set up the gear in advance so I could take some pictures while I worked. So I got the double cluster NGC869, near Cassiopeia, and Bode's galaxy. Not too bad for a harmonic cat and a 60mm small scope.
Been having some fun with trying to get a Hubble palette image of the Rosette nebula using my data, Siril, and the tutorials from Deep Space Astro (www.youtube.com/watch?v=fDhO...) - I couldn't find if there was a bluesky account. My UHC filter isn't exactly dual band but eh - close enough.
A follow up with the Rosette Nebula, NGC2244, this time with correct Darks. Something went wrong with the flats, still haven't figured the flat panel out, but we just crop that zone. Just 1h20min.
Two hours of The Seven Sisters, yesterday night, using my cat and the Askar 60F. This is a great little scope. It comes pre-flattened, so no moving parts inducing tilt on the imaging train. Stars are a bit blown out but I wanted to try and bring out the nebula.
To finish the night, I went for the Monkey Head Nebula, with ~2.7h integration. This one was harder to equalise especially because, as with every time I target nebulae, the freaking satellites decide to show up. Also something went wrong with the flats. Suspect some images had dew condensation.(5/7)