wimvb

That's a very nice monkey head. And from such a light polluted site. 👍🏾

@ONIKKINEN I thought of that. And some 20-40 hours of luminance might bring out the halo and maybe even a hint of the tidal stream. But as it looks now, we’d be happy to get half the time needed during all of galaxy season. I’m not sure I want to invest that time. There’s so much else out there waiting to be captured. the problem is also that I had my camera at bin 1x1, and not the usual 2x2. I would need to recapture all data to get a complete image.

Last year I imaged a blue compact dwarf galaxy, the "Little Cub", named after its parent constellation Ursa Major. Tonight I tried another blue compact dwarf glaxy, substantially larger than the Little Cub; the Bear Claw galaxy in the constellation Lynx. Because the galaxies are strongest in blue (obviously), I started by collecting just that. I soon realised that this galaxy is just too small to make an interesting image. There is no larger companion galaxy, and an image would just be too boring. The galaxy itself is quite interesting. According to images and scientific articles I found, it has a weak halo, ongoing star formation in H-alpha clouds, and even a possible tidal tail from an interaction event in its history. None of these were visible in my data. So here it is, 1 hours worth of uncalibrated data (12 x 5 minutes), collected with the SW 190MN and ZWO ASI294MM

I don’t think there is any scope where I would take darks with the camera in place. The best way is to remove the camera and take darks with a metal cover for the sensor. Do this in a dark room preferrably at night. Note that most plastic covers are not opaque enough to allow taking darks during daytime.

A few hours of clear-ish weather with only a late moon allowed me to visit the Tadpoles Nebula, ic 410. We had a family dinner planned, so I left my telescope unattended for a few hours and hoped for the best. All went well, but after the meridian flip, focus had shifted, resulting in a slight increase in FWHM in green. The sequence was interrupted by clouds moving in, but by that time, thin high clouds had already started to affect the data. Nevertheless, this is a mix of all subs, 40 x 5 minutes RGB and 33 x 4 minutes Ha. The colour data was used for the stars, and the Ha for the nebula. I processed this image with the intent of putting some drama into the clouds, but I added small amounts of Ha to the green and blue channels in order to desaturate the brightest areas. As always, data collected with my SW 190MN and ZWO ASI294MM camera. Optolong RGB filters and Baader 7nm Ha filter.

I think they will come down to earth and grab all the popcorn they can lay their hands on. Then settle on the moon, lay back and watch it all unfold. The question that presents itself now is of course if an AI can derail a thread on a forum as efficiently as a human can. That is the real Turing test. Now, let's attempt to put this discussion train back on track. The AI mentioned that one of the lenses is popular for low light level photography. But that is not the same as atrophotography. Low light level photography may very well be terrestrial photography, where a lens is evaluated completely differently from astrophotography. A lens may be called "soft", or have a good "bokeh". But if you ever hear that in AP, you have a lens that lacks contrast and is poorly focused. Hence, my original answer; don't rely on an AI, but try to get answers for specific lenses firsthand from owners.

If you treat an AI as a search engine, then given enough time, the AI should come up with a text based on what an(other) AI has previously written. Something to ponder indeed. As for the OP, why not ask the question that was put before the AI directly on this forum, rather than asking this forum if the AI output was accurate?

Herbig Haro 653 or 654 or Herbig 1? There is a small but intense star forming region in this part of the NA nebula, with Herbig Haro ojects 649 through 660 and open clustef Herbig 1. All according to Simbad. http://simbad.u-strasbg.fr/simbad/sim-coo?Coord=20+58+16.2577342440%2B43+53+35.104618644&CooFrame=ICRS&CooEqui=2000.0&CooEpoch=J2000&Radius.unit=arcmin&submit=Query+around&Radius=4

Asking an AI to recommend gear is a bit like asking me which is best, Lamborghini or Ferrari. I could tell you either way, but since I've never even sat in one, what is my advice worth to you? Personally, I'd prefer advice from an actual owner, rather than from a story teller.

Yes, I see it too. Nice image, by the way.

Then it doesn't have to be a gradient. More light pollution means more noise. And noise is a random pixel to pixel intensity variation. There are more bright and dark pixels where there is more noise, but we only notice the brighter pixels. Therefore, the noisiest channel can appear as a colour cast, while it isn't. Anyway, Tomato's suggestion to use scnr should solve the problem.

Thank you, gentlemen. The 190MN is a great scope, once you get to know it. An astrophotographer imaging with a mobile setup from Lappland used one for a year, but he got tired of hauling it around in the snow. This tool works at its best from an observatory. Yes, Göran, getting those 20 hours took some determination. But having some level of automation helps. The target is still a late riser, so I just programmed a sequence and let the equipment do its job, without having to babysit a meridian flip. (I don't always trust automated flips. I have the brakes on my mount loose enough, so that if I ever get a pier crash, nothing should be permanently damaged.)

I collected more data on this galaxy, and am now at a total of 20.6 hours, of which about half Ha. Red and Green 17 x 5 mins Blue 31 x 5 mins H-alpha 137 x 4 mins L 121 x 3 mins The additional data revealed very faint ifn. As always, data captured with the SW 190MN and ZWO ASI294MM camera Processed in PixInsight Previous version https://stargazerslounge.com/topic/405752-ngc-4236-in-draco-wip/#comment-4342568

You asked for it: 😉

The moon is shining bright, and for once without a halo. But it's too bright to do any LRGB imaging, so I'm just collecting Ha data tonight. First target was the bright nebula IC 405, the Flaming Star Nebula in Auriga. This is 80 minutes of Ha (20 x 4 minutes at gain 200) with the 190MN and ASI294MM, Baader 7 nm Ha filter Processed in PixInsight. I extracted the stars from the Ha master and inserted them into the G and B channels to create a colour image with white stars. Then added a touch of noise in order to give the image a more natural look when zoomed in. The image is also rotated 180 degrees from its more common orientation to give a more pleasing composition. (This is the orientation from my scope and camera. So I didn't have to rotate anything.)

Here's my attempt with PixInsight. - Dynamic crop (removing stacking edges) - DBE - Background Neutralisation -SpectroPhotometric Colour calibration - Histogram transformation (levels in PS) - Chrominance noise reduction (removing colour noise from the background) - Curves Transformation, luminance and colour saturation In my opinion, if you can get colour in the stars, you can get colour in the galaxy.

You can always follow up with a magnitude vs time curve. 😉

@tomato & @Tomatobro, thanks. I got it. Plus now I've also got good source for online reading.

Excellent. Do you have a link to the BAA article describing the method you used?

2 billion, or 680 Mpc. I had already checked. There are several other galaxies, but there isn't any information besides a catalogue number.

It certainly is faint. Some time ago, @gorann caught this galaxy "by accident" as he was hunting for planetary nebulae with his RASA. RASA makes it look so easy. 😉 https://www.astrobin.com/p7ycko/B/

ngc4236 is a spiral galaxy in Draco, situated about 15 million lightyears distant. This galaxy is rarely imaged with addition of Ha, so I thought I'd give that a go. So far 3 hours of RGB, 2 hours Ha and 3 hours L Gear: SW 190MN with ASI294MM camera Processed in PI The colour data is still quite thin, and I plan to at least double what I already have, as soon as it clears up.

It shouldn't be that dim. Maybe that site shows the absolute magnitude, which would be the magnitude if the asteroid were at a distance of 10 parsec (32 lightyears). I checked on the site, and it really doesn't say if it is. But there may be a live stream from the Virtual Telescope Project (if the sky clears for them). And if it were a magnitude 26.8 object, that wouldn't be much of a show.

It will certainly look like a satellite trail. At 8 pm UTC (kl 21.00) it will flash by at more than 250 arcseconds per minute

I have been in a conversation with a swedish fellow astronomer about this asteroid, which will shoot past Earth tonight. Is anyone else trying to photograph it? This is compeletly new territory for me, and at the speed that it's going, I will probably miss it. It's a bit like having a landscape photographer trying to get shots of a football match. Anyhow, does anyone here have experience of such very transient events?