JR's website on Deep Sky Astronomy

Meade Deep Sky Imager - Gallery 4

April 15-16: First results with the Meade F/D 3.3 focal reducer-field flatterner (FR/FF)

From previous sessions two main ideas were concluded: (1) the DSI is a surprisingly powerful imaging tool although with severe limitations (e.g., deficient colour correction and small field), and (2) coupled with an 10" LX200 F/D:6.3 system, the focal length is still too large and must be reduced. I replaced the first 3.3 FR/FF by a second unit (useable but still deficient), and here I will show some of the images taken. The results, comprising two nights (March 17-18 and April 15‑16), are not completely satisfactory, but begin to be quite acceptable. The DSI can work amazingly well in moon conditions, and even from a place surrounded by parasite lights, easily registers 15m objects. After convenient image processing, subtle details arises on the image, with a quality comparable to good pictures taken some years ago with larger telescopes, but without the need of moving all the equipment to a rural place. Furthermore, the DSI can spot in a few minutes objects that require visually a very large telescope (17.5"). Since my intention is digging information in the DSO images rather than take nice pictures, the DSI is becoming a very precious observing tool to me. However, if I had aesthetic intentions, I have to agree that the utility would have been much smaller.

The second great advance concerns telescope control. After some weeks programming intensely, I have practically concluded the final release of WINDEX. This software (downloadable freeware) has been totally developed in my free time and without any cooperation, in a project that started in 1994 (see this link). Besides other new features, the program is now able to control the LX200. The program is governed from an extremely comfortable multi‑tabbed interface. The combination maps/photos/library/telescope control is granting memorable nights from now on. To my knowledge, no software is as oriented to deep sky observing as WINDEX is. By the way, I have to think in another name for the final release, since WINDEX (=INDEX for Windows) is also the name of a glass cleaner; by now I have had to rename it as "SkyViewer", but I would prefer a shorten name. Suggestions are welcome.

The Whirlpool Galaxy, M 51 / NGC 5094-95

13 29.9 +47 12 CVN GALXY:SM/8.9m/10.8'x6.6'

163ºAP 76u1/37u2/7s/589-2m/11HBc

5 images of 42 seconds each were stacked. This time the galaxy was rather well imaged. A long exposition was the key point to get a bright and detailed image with the DSI.

The Lagoon Nebula, M 8 / NGC 6523

18 03.7 -24 23 SGR CL+NB:E/5m/45'x30'

339u1/145u2/22s/1392-3m/61HBc

16 images of 30 seconds each taken were stacked. This image was the last taken in the session, in twilight conditions, with naked eye limiting magnitude ca. 4.5 m.

NGC 2903 / UGC 5079

09 32.2 +21 30 LEO GALXY:SBbc/9m/12'X5.6'

17ºAP 143u1/74u2/6s/686-2m/32HBc

8 images of 30 seconds each were stacked. I repeated this object to compare the results at F/D 6.3. Clearly, the new reducer is preferable, although I dislike the stellar definition, which is at the limit of acceptability.

M 14 / NGC 6402

17 37.6 -03 15 OPH GLOCL:8/7.6m/6.7'

248u1/106u2/15s/1322-3m/44HBc

3 images of 15 seconds each were stacked. A distant giant globular cluster surprisingly difficult to resolve at the eye, even under very good nights. The DSI, however, had no difficulty in getting a fully resolved image. Amazing.

The Pinwheel Galaxy, M 101 / NGC 5457

14 03.2 +54 21 UMA GALXY:SBc/7.9m/28.5'X28.3'

49u1/23u2/2s/570-2m/10HBc

6 images of 42 seconds each were stacked. Fantastic image in spite of the short exposition. Multiple star clouds with NGC designation are shown in the picture. Very encouraging: I should take longer expositions.

The Dumbell Nebula, M 27 / NGC 6853

19 59.6 +22 43 VUL PLNNB:3(2)/7.3m/480''X340'' 162u1/66u2/8s/1195-3m/24HBc

15 images taken at the end of the night (30 seconds each) were stacked in this composite shot. The image has been altered to get a light profile more similar to the visual appearance. The exposition was a bit short, pity.

NGC 6749 / GCL107

19 05.3 +01 54 AQL GLOCL:11.1m/6.3'

251u1/105u2/16s/1293-3m/43HBc

8 images of 15 seconds each were stacked. This is one of the most surprising globular clusters, lying in a high absorption area. It is visually rather hard to see with the 254 mm LX 200, and usually impossible from Algar.

NGC 6781 / PK 41-2.1

19 18.5 +06 32 AQL PLNNB:3b(3)/11.8m/111''X109''

206u1/85u2/16s/1269-3m/43HBc

9 images of 30 seconds each were stacked. This is the nicest planetary nebula in Aquila. Visually, the asymmetry in light distribution is more striking, although the stratification in colours cannot be perceived.

NGC 6804 / PK 45-4.1

19 31.6 +09 14 AQL PLNNB:4(2)/12.4m/63''X50''

207u1/85u2/16s/1244-3m/42HBc

9 images of 15 seconds each were stacked. This tiny nebulae was registered as a double shell, being fainter the outer one. The central and near stars giving the appearance of a small cluster are also evidenced.

NGC 3239 / UGC 5637

10 25.1 +17 10 LEO GALXY:IrB/11.3m/5.1'X3.7'

145u1/92u2/13s/707-2m/31HBc

14 images of 30 seconds each were stacked. Besides the Moon, a cloud bank was crossing the region. I think that the absence of IR filter help to register several 15.5m galaxies, although introduced a strong red-purplish hue.

NGC4535/PGC41812

12 34.3 +08 12 VIR GALXY:SB/10.5m/6.9'X5.4'0ºAP

194u1/91u2/14s/749-2m/48HBc

15 images of 42 seconds each were stacked. This image is closely similar to the POSS image. Forcing it reveals small background galaxies out of electronic maps.

NGC 4559 / PGC 42002

12 36.0 +27 58 COM GALXY:SB/10.3m/11.0'X4.9'

150ºAP 149u1/72u2/7s/654-2m/30HBc

25 images of 30 seconds each were stacked in this final image. This is a second fantastic (although scarcely visited) barred spiral galaxy in the Coma Berenices area.

NGC 4565 / PGC 42038

12 36.3 +25 59 COM GALXY:S/10.3m/14.9'X2.0'

136ºAP 149u1/72u2/7s/677-2m/30HBc

25 images of 30 seconds each were stacked. It was taken to compare with the performance of x0.63 FR/FF. The picture at the original scale shows the dust lane crossed by small and irregular glowing patches.

NGC 5053 / GCL 23

13 16.5 +17 42 COM GLOCL:11/9.8m/8.9'

150u1/71u2/14s/699-2m/29HBc

16 images of 21 seconds each were stacked. This is the first time I get the cluster clearly evidenced, much better than at F/D 6.3. The brightest star (right) shines with the 9.8 magnitude, and the second (left) is a 12.5m star.