Dan_Paris

Thanks Peter!

Hi, here is a two-panel mosaic of this beautiful area of the sky, taken over three nights with my 200/800 newt from Paris' suburbs (Bortle 7/8). I had good seeing for the Quintet (2.1" FWHM) but for NGC 7331 conditions were a mixed bag, one night with good transparency but poor seeing (3" FWHM), and one night with decent seeing (2.2" FWHM) but clouds, strong winds and threats of rainfall. So for this panel I kept just 70 luminance frames for the stars and the galaxy core, and nearly all of them (330*60 sec) for the extensions and the background. Here is the mosaic (right clic for full res): Crop on the Quintet Crop on NGC 7331 and the Deer Lick group Thanks for looking and clear skies, Dan Technical data 200/800 custom Newtonian astrograph with Romano Zen optics and carbon fiber tube AP900 CP4 mount on Losmandy HD tripod TS 2.5" Riccardi-Wynne corrector ASI183mm ZWO LRGB filters Guiding : ZWO OAG + ASI120mm mini + AsiairV1 Luminance : 300 *60sec for the quintet, 330*60sec for NGC7331 Chrominance : 45*60sec each channel for each panel Darks, flats and synthetic biases Conditions : Bortle 7/8 skies in Paris' suburbs (20km from the Eiffel tower), variable seeing (2.1" after to 3"), some clouds and wind Preprocessing and stacking with Siril, processing with Pixinsight and Rawtherapee

ve ry deep image and indeed nicely framed, well done !

Nice colors indeed well done !

Lovely image, the RAS seems very efficient for this type of targets. You were brave with the rain threat !

I have never heard of this nebula, it was for sure a difficult capture, well done Göran

Excellent picture Peter. The soap bubble in particular stands out very nicely.

Thanks a lot @callisto, @Stu1smartcookie et @glafnazur ! Dan

Hi, this small constellation at the edge of the Milky Way is seldom visited, nonetheless it contains many interesting objects, including small but beautiful galaxies and lot of IFN. Here is a field containing the barred spiral galaxy NGC 7223, interacting with the elliptical PGC 214803 as well as the spiral galaxies UGC 11919 and UGC 11927. I took this picture last night with my 8" newtonian astrograph from my light-polluted backyard in Paris suburbs. Thanks to rather good seeing conditions (2.1" FWHM after stacking), I managed to extract interesting details from these small objects (NGC 7223 is 1,4′ × 1,1′ only), even with my 750mm focal length. First a crop centered on the main galaxies: And the full picture, with several other galaxies and some traces of IFN in the upper part : Thanks for looking, Dan Technical data 200/800 custom Newtonian astrograph with Romano Zen optics and carbon fiber tube AP900 CP4 mount on Losmandy HD tripod TS 2.5" Riccardi-Wynne corrector ASI183mm ZWO LRGB filters Guiding : ZWO OAG + ASI120mm mini + AsiairV1 Luminance : 180 *60sec at -10°C Chrominance : 30*60sec at -10°C each channel Darks, flats and synthetic biases Conditions : Bortle 7/8 skies in Paris' suburbs (20km from the Eiffel tower), moderate seeing (2.1" after stacking), some clouds Preprocessing and stacking with Siril, processing with Pixinsight and Rawtherapee

Very deep view, well done !

Excellent image ! I wish I could image this part of the sky from my place....

Thanks a lot @Paul M, @michael.h.f.wilkinson, @callisto, @bomberbaz @peter shah, @MartinB, @assouptro and @Saganite for your kind words. That's a good question, I should try to install Aladin and check for QSOs in the image. In terms of magnitude, it is not very deep (mag 20.6), I reach usually around mag 21.5 with my setup and sky conditions. I would need first to find space on the walls of my house 😂 Did he enjoy the views?

Hi, M92 is a well-known globular cluster in Hercules, overshadowed by its more famous neighbor M13 but nonetheless impressive on its own right. It is less known that is lies close to a rich deep field containing many distant galaxies. Many of them appears on this picture taken last month with my 8" newtonian astrograph, even from my light-polluted backyard (right clic for the full-resolution picture) : Here is the luminance annotated with ASTAP Thanks for looking, Dan Technical data 200/800 custom Newtonian astrograph with Romano Zen optics and carbon fiber tube AP900 CP4 mount on Losmandy HD tripod TS 2.5" Riccardi-Wynne corrector ASI183mm ZWO LRGB filters Guiding : ZWO OAG + ASI120mm mini + AsiairV1 Luminance : 200 *60sec at -10°C Chrominance : 20*60sec at -10°C each channel Darks, flats and synthetic biases Conditions : Bortle 7/8 skies in Paris' suburbs (20km from the Eiffel tower), variable seeing (from 1.8" to 3"), rather poor transparency Preprocessing and stacking with Siril, processing with Pixinsight and Rawtherapee

Spectacular image Peter, taken with an impressive instrument. What FWHM did you obtain after stacking ?

Thanks @mackiedlm ! clear skies, Dan

The form factor and low weight of the T6 Naglers are a big advantage over Delos and Ethos for travel dobsonians. And personally I don't like too much eye-relief, my 13mm T6 ergonomics are perfect for me.

Hi, NGC 7217 is a face-on spiral galaxy in Pegasus with a ring structure, located 50 millions l.y. from us. Its angular size is rather small (about 3') so a bit challenging for the 750mm focal length of my 8" newtonian, but fortunately the ASI183mm has small pixels and the seeing was rather decent last night (2.3" FWHM after stacking). Thanks for looking, Dan Technical data 200/800 custom Newtonian astrograph with Romano Zen optics and carbon fiber tube AP900 CP4 mount on Losmandy HD tripod TS 2.5" Riccardi-Wynne corrector ASI183mm ZWO LRGB filters Guiding : ZWO OAG + ASI120mm mini + AsiairV1 Luminance : 180 *60sec at -10°C Chrominance : 30*60sec at -10°C for R and B channels, synthetic G Darks, flats and synthetic biases Conditions : Bortle 7/8 skies in Paris' suburbs (20km from the Eiffel tower), decent seeing (2.3" after stacking), last quarter moon. Preprocessing and stacking with Siril, processing with Pixinsight and Rawtherapee

Gorgeous data and processing Robin !

Thanks @orionoffelt and @peter shah for your messages ! (with a very long delay I'm back from holidays...) I managed to shoot more frames the day after, giving almost twice total exposure time (6h luminance overall). I also made a selection of the 120 best frames for the galactic core, giving about 2" FWHM. Here is result, smoother and with finer details than the former version (full-res image) : This active galaxy is known for its ring-like star formation region around its core, with an apparent radius of 5 arcseconds. This structure is quite obvious on an enlarged version of the picture : Thanks for looking, Dan

Hi, NGC 6951 is a beautiful barred spiral galaxy in Cepheus, not far from the more famous Fireworks Galaxy (NGC 6946) and from the Iris nebula. It is surrounded by IFNs, and I was surprised to see them so well on the picture despite the strong light pollution (Bortle 7/8), modest integration time (160*60sec luminance) and some high-altitude clouds. Thanks for looking, Dan Technical data 200/800 custom Newtonian astrograph with Romano Zen optics and carbon fiber tube AP900 CP4 mount on Losmandy HD tripod TS 2.5" Riccardi-Wynne corrector ASI183mm ZWO LRGB filters Guiding : ZWO OAG + ASI120mm mini + AsiairV1 Luminance : 160 *60sec at -10°C Chrominance : 20*60sec at -10°C for R and B channels, synthetic G Darks, flats and synthetic biases Conditions : Bortle 7/8 skies in Paris' suburbs (20km from the Eiffel tower), average seeing (2.5" after stacking), last quarter moon. Preprocessing and stacking with Siril, processing with Pixinsight and Rawtherapee

I am not sure it qualifies as "high end" however I am using this one on my Newtonian and it works very well: no flex, no slippage (of course as it is R&P), extremely low image shift and many threaded connections possible: https://www.teleskop-express.de/shop/product_info.php/info/p5995_TS-Optics-3-Inch-Rack-and-Pinion-Focuser-for-heavy-equipment---M117-connection-thread.html You'd need a custom-made adapter plate to mount it on a newt (this is what I did). Recently Teleskop service added a version with a newt adapter plate but price is much too high https://www.teleskop-express.de/shop/product_info.php/info/p14733_TS-Optics-3--rack-and-pinion-focuser-for-Newtonian-telescopes---carries-up-to-6-kg.html Whatever you choose, if the focuser allows a threaded connection to the imaging train it is much better.

Hi, last night, amidst the heat wave, I took some luminance data on this beautiful galaxy with the ASI183mm that I have blended with chrominance data with the ASI1600mm from last year. In both cases with my 8" f/4 imaging Newtonian Thanks for looking, Dan Technical data 200/800 custom Newtonian astrograph with Romano Zen optics and carbon fiber tube AP900 CP4 mount on Losmandy HD tripod TS 2.5" Riccardi-Wynne corrector ZWO LRGB filters Guiding : ZWO OAG + ASI120mm mini + AsiairV1 Luminance : 200 *60sec at -10°C with the ASI183mm Chrominance : 30*60sec at -10°C each channel with the ASI1600mm Darks, flats and synthetic biases Conditions : Bortle 7 skies in Paris' suburbs (20km from the Eiffel tower), average seeing (2.5" after stacking), last quarter moon. Preprocessing and stacking with Siril, processing with Pixinsight and Rawtherapee

I had issues with the mini EFW (bad luminance calibration because the filters do not reposition exactly in the same position). My solution is to shot the luminance flats at the end of the flat sequence, and then to start the image sequence with the luminance. I read that enforcing unidirectional motion of the filter wheel would also solve the problem, but I did not try yet (in the fear of loosing a night of data).

Hello everyone, The tadpole galaxy, with its long tidal arm, is well-known from the iconic HST picture. Here is my version from the suburbs of Paris, under a nearly full moon, with my 8" f/4 astrograph. Cropped version : Full field picture: Thanks for looking, Dan Technical data 200/800 custom Newtonian astrograph with Romano Zen optics and carbon fiber tube AP900 CP4 mount on Losmandy HD tripod TS 2.5" Riccardi-Wynne corrector ASI183mm + ZWO LRGB filters Guiding : ZWO OAG + ASI120mm mini + AsiairV1 Luminance : 140 *60sec at -10°C Chrominance : 20*60sec at -10°C for R and B channel, synthetic G Darks, flats and synthetic biases Conditions : Bortle 7 skies in Paris' suburbs (20km from the Eiffel tower), mediocre seeing (2.8" after stacking), gibbous moon. Preprocessing and stacking with Siril, processing with Pixinsight and Rawtherapee

Excellent wide field image Göran, I never realized that those objects were so close to each other !