drjolo

I used to have this corrector some time ago with GSO 150/750 newtonian and Atik 383 as well - I think this is the one https://astrojolo.com/gears/pin-point-stars-on-sale/ - it also reduces the focal length a little. It was never easy to have it all collimated and aligned, but should be doable. These are example images I made with that setup (though resolution is small ) https://astrojolo.com/wp-content/uploads/2016/10/2013-09-06-NGC6914.jpg https://astrojolo.com/wp-content/uploads/2016/10/2013-09-27-NGC6888-Ha.jpg

I already imaged M51 four or five times. When spring comes and CdC shows me M51 high in the sky, I just cannot resist This time I wanted to focus on galaxy detail and features, so I needed to wait for good seeing. In the middle of April a few nights happened with decent seeing and also quite good transparency. Unfortunately Moon was also present in the sky for most of the time, so I did not reach as deep as I wanted, and SNR is also not perfect. But if you take a closer look into the left part of image, below these three bright stars triangle you may spot some faint patches of light - I checked them in SDSS and these are galaxies located 3-5 billion light years away. There are a few more also to the right of M51. And AT2019abn (Intermediate Luminosity Red Transient) has also been recorded Meade ACF 10", CCDT67, QHY163M, EQ6, LRGB 400:40:30:30x60 seconds (gain 100), seeing good, transparency good, Moon present. And luminance only:

Nice capture, and many faint fuzzies in the background. Have you used any coma corrector?

Thanks Yes, I use autofocus and it works well. However I have separate crayford focuser attached, so I do not use OTA focusing knob at all. Also temperature compensation works well in this combination.

Uh, this is amazing image. And clusters are well defined there - I have not seen this image before.

I always like to look for distant worlds in the sky, and when I stacked 400 minutes of luminance captured for my new project, I found some faint flocks at the frame edges. It turned out to be distant galaxy clusters located 2600 and 3000 millions light years away: http://simbad.u-strasbg.fr/simbad/sim-id?Ident=%408444694&Name=XMMXCS J0953.7%2B6947 and http://simbad.u-strasbg.fr/simbad/sim-id?Ident=%4010548357&Name=SDSS J095324.38%2B693648.7 . M82 is about 12 million light years away for comparison. There are not much information available about these clusters, just two more among plethora of others. Faintest recorded galaxies in this image are about 22mag. 21-22.04.2019, Meade ACF 10" f/10, AP CCDT67, EQ6, QHY163M, L 400x60 s, gain=100, suburban sky, seeing and transparency good.

Thanks It was Ha 55x5, Oiii 25x5, RGB 18:12:12x1 minutes for Crab, and Ha 115 minutes in 5 and 2 minute subs for Eagle.

Definitely you need to power stick with regulated voltage. 12V battery with DC converter to 5V is good idea, for powerbank - I do not know if you can draw constantly 2-2.5A, maybe yes. If yes, then it would be more convenient, because you do not need to use DC converter. But power bank contains usually 3.7V battery and boost converter to 5V, so the max current is limited by output converter.

In some extent it depends on the USB ports the stick is equipped with. I have measured power consumption of several sticks and mini PC, and the rated power is usually a sum of stick own power requirements plus USB ports. USB2.0 port should be able to provide 0.5A, and USB3.0 1A (but of course not all USB components will drain that much power from USB port). So now is all up to what you plan to connect to your USB ports. If all USB ports will be loaded with maximum allowed power, then you need as much current as it is stated. Otherwise stick itself requires about 1.5A (at 5V) maximum when CPU is 100% load.

It is always a hard decision - it somehow depends on your sky quality. If your imaging location provides visible Milky Way and NELM at level 5-5.5mag or better, then OSC camera will do the trick. But if LP is worse, then you probably achieve better results using mono camera with LRGB and narrowband filters. This is my case, I have NELM limited to 5mag during good nights, sometimes it reaches 5.5mag. I have tried with OSC cameras and DSLR few times already, and always got back to mono. However I was pretty happy with having for some time both QHY163M and QHY163C cameras. I used mono for luminance, OSC for colour and it worked pretty well (like here for example https://astrojolo.com/astrophotography/galaxies/m106-after-four-years/ ). I also wrote a post about it at my blog https://astrojolo.com/gears/colour-camera-versus-mono-price-of-comfort/ - at the end you may see sensitivity comparison between OSC and mono cameras.

Congratulations on your captures! Here is my five picks: Heart and Soul and comet (with Samyang 135 and QHY163M): Four next were made with Meade ACF 10" and QHY163M.

Thanks! Yes, I plan to add colour to at least some of them. And also more luminance to Abell 1185

This is set of this year spring galaxy hunts I made. All images were shot at my roll-off shed with Meade ACF 10" telescope and QHY163M camera on EQ6 mount. Conditions were different, but usually both transparency and seeing were average-good. I am pretty happy with this setup capabilities under my suburban sky, one thing I miss is more clear nights Abell 1185 cluster with "Guitar" feature. 120x1 minute, gain=100 Messier 82 galaxy. 40x2 minutes, gain=0 NGC4535 galaxy. 45x3 minutes, gain=0 NGC3628 galaxy. 55x2 minutes, gain=0 NGC4762 and 4754 lenticular galaxies. 95x1 minute, gain=100 Hickson 68 group. 140x1 minute, gain=100 Thanks for watching!

Thanks! Hmm, I didn't plan to add Oiii - the Ring itself is bright enough for RGB only. But maybe it is worth to check the outer shell if it shines in Oiii... ?

Thanks! Yes, indeed some galaxies have been captured, and some of them are not identified in PGC catalogue:

It's been already 6 years since I imaged M57 for the first time with 6" newtonian and DSLR - I was a little bit disappointed then This time I was prepared a little bit better and collected some subframes over three short May and June nights. It is about 5 hours of total exposures over Ha and LRGB filters. I wanted to reveal nebula outer halo and it worked, however I found it quite faint. It was barely visible in 50 minutes luminance stack, but Ha narrowband subframes helped. This halo was discovered in 1935 and most probably it contains stellar wind that was emitted before the nebula was born. Thanks for watching!

In HEQ5 there are following bearings: 6x 6006 2RS - these are main RA and Dec shafts bearings 2x 30205 - tapered rolled bearings 4x 689z (or 618/9) - these are small bearings for worm shafts I used EZO bearings for worm and SKF/Timken for others. As for plastic washers - these are used for precise placement of worm at worm wheel. There probably should be some washers already, because if you want to replace them, you need to use new one with the same thickness. I cut out proper dimension washers from teflon foil.

Do you calibrate your flats with biases or dark-flats to remove offset? I actually was not able to find a way to proper calibrate images with Pix. I use Maxim for this - its Set calibration library is fast and excellent tool.