Last updated: 19 May 2002 |
Subject: Galaxy Hunting with the ETX-90RA Sent: Friday, May 17, 2002 14:01:56 From: tiffbrown@earthlink.net (Tiffani Brown) The Hard Way by Chris Brown Galaxy Hunting with the ETX-90RA They thought I was joking. I had a perfectly good 8-inch Dob in the garage, and I was on my way to the high desert for a little deep-sky observing with an ETX 90RA! Why dont you take your big scope?, my friends would say, scratching their heads. Nope, I said, Its time to see what this little scope will do. I wanted the Meade ETX-90 mainly for travel, and for showing off the planets to my distant relatives and friends, but I was curious about its deep-sky ability, too. After all, I didnt want to be in the middle of nowhere with a boring telescope! My trip to the desert was the perfect opportunity to find the answers. Galaxy hunting with a 90mm f/13.8 telescope may seem like an exercise in frustration, but I stacked the odds in my favor. Along with the addition of a red-dot finder, I brought along a 32mm Plossl giving me 39x and over one degree of true field. I also grabbed my trusty 42mm Ultima (29x, 1.2 degrees) for good measure, after all, the lower the mag, the brighter the image (within reason). I used Meades new #884 tripod to keep a steady image, and a wooden clothes pin on the focuser knob eliminated any shakiness during focusing. The 1-speed motor drive allowed nice, long looks at DSOs, which proved to be quite a luxury to someone used to Dob driving! I brought along no charts for this exercise, instead relying on my memory (I visit the high desert often) to find my targets. I was only interested in counting visually obvious objects in order to get an honest measure of the capabilities of the infamous ETX 90. The high desert of Yucca Valley was very windy and extra cold that weekend, as demonstrated by the bank thermometer down the street displaying temperatures well under 50 degrees! As night fell, the icy winds started to subside, so I decided to begin my observing session. After polar alignment, a quick look at Jupiter revealed to me that this was no night for planetary viewing. The image was wavy and indistinct. The upper atmosphere had alot of calming down to do, but I did notice the fabled excellent desert clarity as demonstrated by the naked-eye visible Beehive cluster! I pointed the scope to M42, and was rewarded with a bright, multi-layered fan shaped cloud that filled the eyepiece! I then pointed to M1, not expecting much, but the Crab Nebula was an easy find, just a dim smudge skating the very edge of averted vision! By now my face was numb from the cold. My fingers were quite sore, and my speech was reduced to a mumble. Time to break for supper. After a warm meal, the outside temp seemed to rise 30 degrees, so I got down to business. At first, I was starhopping by turning the Dec and Ascension knobs, but I soon found out that the best way to find objects was to grasp the dew shield and aim it as if pointing the worlds smallest Dob! The diabolical 8x21 finder was actually quite useful using this method, and was able to reveal M35, 36, 37, and 38 quite clearly! These clusters were very bright and full at 39x, yet NGC2158 by M35 was a no-show. My first galaxy was M104, the famed Sombrero. It was relatively bright and clear, with its predominate dust lane easily visible at 39x with the Plossl, but the 42mm Ultima definitely showed brighter details. I tried my 15mm Axiom (83x) which I consider to be my highest contrast eyepiece, but the image was severely dimmed. Barlowing the eyepieces brought similar results. Next was M65, and M66 in Leo. Again, the 42mm was the eyepiece of choice, and I could see definite brightening at the center of both galaxies, as they glowed in the same eyepiece field. I tried for NGC3628, which shares the same field as M65, 66 in my 8-inch reflector, but again, it was too dim for the 90mm to see. Still, I considered sighting these dim 9th Magnitude galaxies to be a real victory for the 90MM ETX. The Hard Way by Chris Brown Galaxy Hunting with the ETX-90RA, Part II In keeping with my reputation for doing things the hard way, I decided to take my little ETX-90RA to the high desert for some galaxy hunting. Armed with only a red-dot finder and a few low power eyepieces, I was very satisfied with the performance of the ETX so far, as it made quick work of the Crab Nebula and a few dim galaxies around Leo. I decided to pitch the polar alignment, and point north for a while in hopes of finding some of the brighter galaxies in and around Ursa Major. First was M51, the Whirlpool. In the city, M51 is invisible to me, even with my 8-inch Dob. The ETX quickly found this small galaxy in the deep, dark desert with minimal effort! In contrast to the dimmer galaxies found previously, the Whirlpool was better resolved using my 32mm Plossl, rather than the 42mm Ultima, which features more advanced coatings. Hmmm. The smaller companion galaxy remained a small smudge, but the larger galaxy showed decent detail, and in times of good seeing, I could make out the direction of its swirl! Very beautiful! Barlowing the Plossl to 78x only showed two dim, unequal sized smudges, still quite good for 90mm! I steered towards M94, a bright Mag 8 galaxy which is easy, even in the city. The ETX showed a bright, round blob with a brighter center, piece-of-cake! I decided to try my favorite galaxies, M81 and M82. These are a real crowd pleaser, especially when they share the same field of view, which I was able to accomplish with the ETX at 29x. M81 was a bright, distinct oval, with no spiral arms visible. M82 took on a very slight rough appearance, and I spent about 30 minutes marveling at the view! Higher magnification took less away from these targets, but I find M81, 82 to be more visually exciting as a low power pair. My final target for the evening was M13 in Hercules, which was quickly rising in the Northeast. I found the object to be extremely bright, appearing as a large, dense star! While the center of the globular cluster was washed out, the outside stars resolved nicely like little connect-the-dots legs, giving the cluster a striking spider appearance that its so famous for! Magnificent! Despite its compact dimensions, the ETX 90RA was a surprisingly good deep sky companion. What it loses in aperture, it makes it up in image sharpness and contrast. True, a desert sky can make a hero out of any telescope, and in the desert, even the ETXs infamous finder scope was performing well! One has to realize, however, that these prime conditions are getting harder to find, so it can be a real advantage to travel with a light weight telescope to improve your mobility!
Return to the top of this page.
Go back to the User Observations page.
Go back to my ETX Home Page.