Luminance only, 60 seconds subexposures, 10 stacked shots. FITS Liberator, GIMP. Slight curve in GIMP. North is up; east is left. There are slight registration problems in this image. Looks like the polar alignment is off a bit.
Messier 65 (M65) is south-west of centre, a compact edge-on spiral galaxy with an intense bright core. Finally Messier 66 (M66) is south of centre, a large barred spiral galaxy. I first viewed the Charles Messier objects on 8 May 2011.
NGC 3628 is to the north. Large but faint. Dark dust lane in the foreground. It was on 11 June 2011 that I first visually spotted the fainter edge-on galaxy. I imaged this galaxy, the Hamburger, on its own recently. Also a target on the RASC Finest list.
Together this group is known as Arp 317. It's fantastic seeing them all together in one field. That view is approximately 1¼ degrees square.
This is my first run with the Mini-Ralph Observatory (MRO) in Nova Scotia, currently located at the Abbey Ridge Observatory near Stillwater Lake.
The optical tube assembly is a Tele Vue Genesis 100mm. It's on a Celeston AVX German equatorial mount—atop a custom made wooden platform. The (CMOS) camera is the ZWO ASI 1600 MM monochrome mated with a EFW filter wheel with 8 positions. The whole rig is manually set up and polar aligned on clear nights.
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Now for some deep stuff...
Tiny galaxy IC 2708 is visible to the south-west, near the bottom-right corner of the image.
The little sliver of IC 2763 shows to the south-east.
Left of centre, very close to a star, is the edge on distant galaxy IC 2745.
Quasar WEE 48 is north-west of NGC 3628 while WEE 55 is to the north-east. 48, aka Q1117+0139, is magnitude 19.9, has a redshift (z) of 2.06, and a light time of 8.9 Gyr. 55 or Q1118+0139 is mag 20.5, z 1.94, and light time 8.7 Gyr. WEE 55 is a maybe... star J112104.1+133822 at mag 16.8 is nearby... And WEE 48 is near J111944.6+133818 at mag 15.5. On second thought, I don't think I nabbed quasars. Looks like the mag limit in this image is around 16½.
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Millie liked the image.
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MRO's minion reported "I still have some work to do on image calibrations for CMOS cameras - a bit different than CCD but not a big issue so far."
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In an effort to learn the limits of this new rig, I did a deep dive. Looks like I can tag stars around magnitude 17. And there's a very faint pair (mag 16) of equal stars with J111920.2+132330 between 3628 and 65, east of the bright star, with a black line between. SkyTools says the separation is 9.0 seconds of arc. So it looks like MRO will give splits of equal stars around 8".
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Wikipedia link: Leo Triplet.
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