After several months of waiting yesterday there was the first light of 60 cm. This is a Dobsonian similar to the bottom of this page (but with significant changes to which I shall return).
In the afternoon I went to Colle Saint Lucia primarily to adjust the length of the tubes. The photo shows the primary Romano Zen, 60 cm, and Marco controls in that there is an authentic signature.
Unlike most amateurs, that whenever they have a new tool generate rain and hurricanes, to me it always happens that the first night will be good to make the first light. Until two days ago nobody would have bet a cent on Saturday that he would have used a telescope. But ... Later
better describe the instrument. For the moment only two words on the optics. The large mirror is like a car engine: it is certainly working well (which is of good optical quality), but it is also powerful. The quality of optics alone is not enough unless you also have the power. And this is the motivation that behind the leviathan.
how powerful is the engine of this telescope? ... well ... follow me in this brief report.
From Saint Lucia Hill, the evening was clear that looming, we went to Giau. A chance to revisit a place I'd seen in 2007.
The temperature at night fell to minus 17 ° C. +5 ° to Hill that there were nearly 20 ° C to jump. I have not been able to install fans and I used the leviathan in natural cooling. The open cell design allows the obsession though not with the same results of the extraction of the boundary layer.
We settled on the pitch. Unfortunately there are many restaurants and hotels along the pass that keep headlights turned on (contrary to the law now regional). But the worst was looking out towards Cortina. Not only the city produces a remarkable light pollution: there were those who seemed to me the illuminated ski day (and night until one of these were). The SQM
started from a poor 20.95 to 20, rose slightly to 21.10 to about midnight and went a bit 'more at one o'clock at night 21:25 to 21:35.
Milky Way washed and certainly nothing to do with the Three Peaks or Val or Visdende Peralba. Between 21.1-21.3 and 21.5-21.7 is "an abyss".
But the "abyss" that we are interested in others as it makes an engine of this power? It 's true The diameter is optional and that the optical quality is more important?
Not that I did not know the answer, but it took was a look at some classical pieces, including Mars, to get a clearer answer (and obvious) you can not.
After a while 'traffic to mount (for the first time) and the leviathan to align the finder, the first object has been framed ... M42! 32 mm eyepiece (which are 93x). On a fire of 2985 mm F / 5 stars behave well at the edge of the field (unlike most open optical and shorter focal length) eyepiece even medium-end we were using. Stars that seemed "fine powder" (impression then systematically obtained on all open clusters observed in which the color of the stars stood out above all more pronounced than I had before in 40 cm). You could see tiny stars in the nebula. Moving on to 21 mm (142x) the E and F of the Trapezium were there: the seeing was not very evident despite some of the best and even thermal adaptation. Not only that there were much weaker than other stars in the nebula.
One interesting thing is that the effect of "color" (green / pink) was less obvious than in the 40 cm. Because I think the bigger picture (the same exit pupil) reduces misinterpretation of the visual system (a little 'what happens when you put off the central area of \u200b\u200bthe nebula and we observe only the wings and they seem no longer pink). I noted in particular the filament marked with the letter "A" in this article and I compared with the main part of the wing next to it (much brighter). Same color (gray) in spite of the filament is rich in H-alpha and OIII wing is much richer.
Another item noted was the group of nebulae of M78. 4 nebula visible areas and the dark cloud that separates them (the telescopes, incidentally, shows a very high contrast and I think that depends on whether the surface is very smooth, both generous diameter: both have an effect on the final MTF ).
Observed clusters in the area of \u200b\u200bM46, M47, NGC2423 and 2414. The advantage of the "powerful engine" here is manifested in the colors of the stars. M46 then was "touching," with its planetary nebula in which pushing a little magnification (213x) internal emerging stars.
I then wanted to see M1. At 142x it was possible to see many stars in the nebula (many more than those I mentioned in a past article, and observed with a 40 cm). But the surprising thing was up to 213x and insert a nebular filter: the nebula has revealed a "swarm" of lights that were evidently filaments.
NGC2158, close to M35 is "resolved" in stars, where the word "solved" has a meaning that is not easy to explain. The helmet is
Thor was another question, already observed in the past (report available on the blog) and I wanted to see again. The filter and the magnification of 213x (at the exit pupil of 3 mm) revealed an intricate web of micro filaments were not visible in the previous 40 cm. And we
high resolution. It 'a field in which often happen to read "opinions" that the diameter of the telescope does not count (no more than 15-20 cm). Would count only the highest quality. We observed Mars at 420x, despite seeing the mountain, the temperature of minus 17 ° C, the temperature difference of 20 ° C, less than optimal acclimatization. Mars was "recorded". He obviously noticed the disturbance of the atmosphere and the heat but it was evidente che il grande motore stava ancora andando al minimo, tanto erano netti i bordi nei momenti nemmeno troppo infrequenti in cui l'aria si calmava. Diverse zone di basso contrasto nelle grande regione desertica erano visibili e colorate. Durante queste osservazioni ho avuto modo di osservare anche alcune stelline di campo (non molto luminose) e "intuire" vagamente la struttura delle speckles (tanto sono fini). Ovviamente non siamo stati molto su Marte perché avrò modo di ritornarci da casa in condizioni migliori.
E infine una menzione alle galassie. Abbiamo scelto il tripletto del Leone. Le tre galassie mostravano benissimo la loro struttura (a spirale e alone due e vista di taglio con banda nera e deformazioni mareali l'altra).
Addendum. Comments of Mark.
See "born" on a giant piece at a time in the afternoon was a particular emotion, and already the first work to be finalized at least made us realize that the jump from the point of view of operational and logistical complexity compared to 40 cm is significant.
the evening we took a long time to mount the tubes and we found it difficult to align and collimate the finder, but it was assumed that the first shot could not go smoothly right away. So we were able to observe a few objects, not only for the initial loss of time but also because we had become familiar with the finder again with a 90 ° prism can be difficult to succeed to frame the star of departure (you first need to orient the telescope by moving the good from the ground, and only after climbing a ladder and start to use the finder, and to facilitate the first thing I suggested to adopt a red-dot) and also I noticed that depending on the height at which you look you need to adjust the rotation of the prism finder, and this causes the rotation of the field, with obvious opportunities to struggle to recognize it unless you know with that first corner is turned. But with a little 'habit of the "human goto" will soon return to full speed. Then
serve other small improvements as a softening of the mechanical movements and a correct balance.
Turning to seen objects, add comments to those not mentioned by Mauro. The Flame nebula with 21 or 14 mm occupied the entire field and it's nice to see it with Alnitak out of the box. While because of imperfect sky we dropped the Horsehead.
Thor's helmet and the M78 group were certainly the best ever seen. M78 appeared larger than usual and you could see even weaker than the southern part extends beyond the star GSC 1108 116, while the weaker components of NGC 2067 and 2064, located in the main W, if the first (when you could see, of course !) appeared as separate nebulae, now all three have become a single object with the black clouds above (as in reality).
Staying within the nebulae, We also spotted the Christmas tree to try to see the cone, but then came the first problem of fogging of the eyepieces so I declined to see both you and the nearby NGC 2261. A chapter
they deserve it too open clusters, perhaps too often snubbed but now with this opening for me are to be reassessed because the stars become wonderfully bright and colorful. In addition to those already listed by Mauro, we also saw M41 and M50 and I liked a lot. For the Pleiades 100 magnification instead start to become many, but still the ubiquitous reflection nebulae are always beautiful.
confirm that M51 was probably not the best with the best view of 40 cm, but we also cielo da 21,2 e il secondario brinato, quindi non oso immaginare come sarà nelle condizioni ottimali!
Discorso simile per Marte: non si vedevano particolari più piccoli di quelli che ho visto col 25 cm nelle serate migliori perché l'ingrandimento era lo stesso, però il contrasto delle macchie di albedo era altissimo e l'elevata luminosità rendeva più facile vedere il tutto. Questo già fa capire che un 60 cm in condizioni mediocri, con collimazione e acclimatamento imperfetti, è già almeno a pari di un 25 cm in condizioni perfette. Il mio problema principale è stato la difficoltà di inseguire, anche perché oltre i 60° il movimento in azimut è molto difficoltoso (e in meridiano è quello l'asse to move more to follow) and are also used in pursuit of motorized telescope.
Finally, we have had confirmation of a prediction almost obvious: if the 32 mm eyepiece telescopes with small to medium is not used nearly ever, this is almost always used because the minimum magnification of 100X, with a maximum range equivalent visible of 45-50 ', begins to be a major constraint.
Conclusion: while we have saved for a corner this new moon after losing two in a row, then this first taste of the beast has increased even more appetite and curiosity. We hope that next time it is fully operational because we have many galaxies to see.
0 comments:
Post a Comment