Overdue First Light: Astrotelescopes 152 f/5.9
Posted 01 November 2012 - 10:58 AM
I wouldn't rule out all minus violet filters on the basis of trying just one.
The MV-20 from Sirius (no longer made) aggressively suppressed much of the false color on double stars at high magnification. I didn't try it on Luna, though, but will.
I think you have to look at the bandpass data for the MV filter in question (they differ model to model) and then the color crossings of this scope, in order to predict what MV filter would be optimal for the optic.
But as you say, if you plan on using it for DSOs and wide fields, I suggest M42 at ~100x, and reporting back on whether you could easily pick up Trapezium E and F. Context and resolution all at once. Should be sweet on that target.
Posted 02 November 2012 - 01:08 AM
@ Jim: Like the Chromacor, the MV-20 is one of those really hard to find items. I used a Baader minus fringe filter to see how it does on the moon. Will get back to you on M42 when the Gods of weather cooperate and someone shoots the moon out of the sky.
Posted 02 November 2012 - 07:40 AM
You think I will be waiting THAT long for setting up the 152 in between the FS102 and the 18"??? You must be kidding... Monday moonrise 10pm, good conditions expected!
Location coordinates Latitude 34.815607, Longitude 33.321533 (give or take a few kilometers). Planning to be out hopefully 8th and 9th of November.
Posted 02 November 2012 - 09:14 AM
I understand your frustration. It took me 13 months to get a Chromacor. I am waiting like you to see what happens with the Raycorr.
Posted 02 November 2012 - 10:15 AM
Just teasing you. I last visited in 1985 - in the summer - so my view is biased, I'm sure.
I worked for a year on a wheat farm outside of Thessaloniki, and took time off farming to travel Greece, Turkey, Crete, Cyprus, other minor islands, Lebanon and northern Egypt.
I'm sure Cyprus has changed a lot, but in 1985 it was pretty sleepy and very quaint. I think the holiday condo boom for Brits was a few years away at that time.
I have many happy memories from that part of the world.
Posted 02 November 2012 - 10:34 AM
@ Rolandos: Monday it is!
@ Jonathan: This Raycorr saga is never ending. I hope they release the dang thingies soon!
Posted 02 November 2012 - 01:06 PM
Nicos, I thought the sun always shined on Cyprus.
Just teasing you. I last visited in 1985 - in the summer - so my view is biased, I'm sure...
Hi Jim, good to know that some Americans do visit our little corner of the world
Cyprus did change a lot, the last few years have seen a steady influx of wealthy Russians replacing the Britons. Unfortunately, more development means more light pollution. But there are positive changes: there are people now eith 16 and 18 inch dobs (three years ago a 12" was spectacular!), lots of refractor guys, some crazy people who test equipment all the time, and yes, the sun still shines a lot!
As Nicos said, you are welcome any time to visit again with astronomy in mind! And, by the way, congratulations on your reviews - the one on the AT 152 made me more anxious to test it than even Nicos who bought it!
Best regards from the island of Venus!
Posted 06 November 2012 - 01:22 AM
@ Jim: Orion wasn't high enough by the time the moon reared its ugly head up last night to make a fair assessment on Trapezium E & F. Next time tho!
To add some gravy: The scope performs beautifully on DSO. Veil Nebula, North American Nebula and Orion Nebula show lovely textured structure.
NGC 253 and NGC 288, Double Cluster are quite enhanced vs my 4". Not that I expected any different of course.
At f5.9 field curvature makes itself apparent as with the Nagler 31 and with Ethos 21, there was a need for a touch of refocusing on the edge of the field vs center.
Pleiades: Jaw dropping. Nebulosity around the sisters clearly visible. Always envied what I saw in photos but it took Pig to show me in real time. Now I understand why people love the Pleiades. Sisters got a lot of character if you can see that beautiful ethereal texture around them. They are jewels indeed!
But back to the Halloween comment: Jupiter is fugly in this scope. Pardon my French but even though there is a lot of detail coming out, chromatic aberration clearly robs contrast and becomes annoying.
As the moon reared its ugly head, in one corner weighting 24 pounds was my TS152AR with a 8mm Ethos @ 113x. In the other corner weighting 6 pounds was my AT72ED with a 3.7mm Ethos @ 116x. Tiny Tim KO'd Pig in 2 seconds flat. No false color on the ED but with the AR, the moon resembled a nice piece of cheese both in color and texture.
The Achromat was also unable to compensate for the fact that the moon was low over the horizon, tossing in hues of green and blue and (insert favorite color) as the seeing wavered a lot. The ED scope was unaffected. Turbulence was evident due to the mon's position, but no false color and a more contrasty view.
Buy this if you want an el-cheapo 6" refractor with fantastic contrast on DSO, nice sharp images for your choice of faint fuzzies, in a manageable package (manageable depends on many factors, but Pig is not that hard to set up).
Don't buy this if you want a planetary scope. ED or APO or SCT or MCT or Reflector will serve you better.
Me, I am happy overall. I got exactly what I wanted and exactly what I expected.
Posted 06 November 2012 - 05:15 AM
I have been using steadily two refractors in my astro career, a Tak FS102 and a Synta ED80. I have observed all planets (including the moon) and many of the best / brighest deep sky objects through both of these refractors, as well as through many reflectors from 4.5 to 18 inches.
M31 at the zenith was great. Quite bright, lots of low contrast detail with the dark lanes and faint outer regions of the arms well defined. Impressive.
Pleiades: Excellent framing with the 31 Nagler. The nebulosity around Merope was nothing sort of amazing. I would buy the scope just for this picture. But (yes, there is a "but"): I could detect easily purple around the brighest stars. I did not look for it. The color just showed itself. Obvious. Not detracting from the beauty of the image, but IT WAS THERE.
NGC 253 was detailed, quite bright, showing mottling on the core.
NGC 247 was visible with direct vision, and despite its faintness, some structure could be made out...
Gamma Andromedae: Nice double, but the fgaint companion was a bit "drawn" in the violet haze around the yellowish primary.
Jupiter: Man, the scope is not intented for planetary viewing. There was a lot of violet around the planet. The planet itself had a strange light yellow - lime cast on it without any filters. Low contrast. I had spent two hours observing Jupiter with the FS102 the previous night, and there was simply no comparison between the two - in the Tak Jupiter appeared with the same pure colors that were evident in my color-free 18" dob. Adding filters did diminish the violet, but it also enhanced the yellowish cast. Not for my taste.
The Moon: Although low, the color was again very evident. A major violet wash. The low altitude of the moon meant a lot of trembling of the image, and you could see craters immersed in violet and greenish color, especially at the shadow edges. Nothing of that sort was visible through the other scopes.
So, what do I think? The scope should not be on the list of anybody seriously considering a planetary scope. Also, people thinking about an "all-around" scope should be prepared that the 152 will not perform well on the moon and planets, or even on the brightest double stars. But, I did like its performance on most deep sky objects. Even the violet around the brighest Pleiads was not enough to detract from the beauty of the scene. North America nebula, Pelican, the area around Gamma Cygni, the Veil, M42 (even at its very low altitude) all were very very pleasing and beautiful in this scope. Being a deep-sky observer, had I had enough storage space at home, I would consider such a scope as a "grab and go" alternative for my 18" dob for shorter sessions. But for the moon / planets I would stick to my other two refractors...
Posted 06 November 2012 - 05:59 PM
I'm sure these reports will be helpful to others, as well, adding to the value of this thread!
Sounds like you both had a good time, too!!! THANKS!!!
Posted 06 November 2012 - 07:05 PM
If you haven't pulled the trigger before the Tucson show, and get a chance to look through that new APM 6" ED doublet, I'd love to hear your impressions of the scope.
Posted 06 November 2012 - 07:45 PM
Posted 07 November 2012 - 02:57 AM
Jim, most of the smaller Aegean islands, and especially those away from the mainland coasts (whether to the east or west) should still be free of light pollution. But you should avoid islands that have become famous as tourist destinations (such as Kos, Santorini, Mykonos, Naxos). The Mediterranean is still acceptable as far as light pollution is concerned. Even on mainland Greece around the Pindus mts area you can get very dark skies. On our own island (Cyprus) we still get 21.3 sqm readings on "average" nights at sites within 40 minutes drive... Let us know if you think of coming over this area again...
Are there any Aegean isles that are well-suited to astronomy from a light pollution perspective?
Posted 09 November 2012 - 03:57 PM
Posted 03 December 2012 - 02:13 PM
Posted 03 December 2012 - 03:02 PM
And that is a near perfect use of a richest field telescope (RFT). My favorite use is similar, though given that my maximum pupil dilation these days is just about 6mm, I tend to top out with a 34-35mm 68-70 degree eyepiece. Because the Astrotelescopes 152 is so fast, I find that well corrected wide fields like ES 68s and 82 and Naglers and Panoptics help maximize the well-corrected true field.
But yeah, it's a nice cruiser; like a 6" monocular.
Posted 03 December 2012 - 04:54 PM