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unsatisfying session


rockystar
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I know we're all supposed to make the most of each opportunity we get, and I've seen that a quite a few people had some good sessions last night and early this morning, but last night I just didn't enjoy my time at the scope. 

I started with some low mag (x56) views of the moon, that's always really cool, if a little bit blinding, so I decided to crank up the magnification (x143) and add a variable polarising filter, thought I'd gone to far with the filter as I could no longer see anything, using naked eye confirmed that the clouds had covered the moon.

Swap the eyepiece back out and find something else. I'll give the double cluster a go, I've only seen it once - couldn't find it, think I was too low in Perseus. Let's try M13, nope can't see Hercules. Time to get out Turn Left: Cassiopeia nice and high with a few options - struggled to navigate this area with EQ as seems to be right on that point where RA & Dec meet (not sure that's the correct description, but I'm sure anyone with a manual EQ will know what I mean) and I find it difficult to move the scope in the required direction. 

Clouds have cleared from the moon, so back over there, let's try again. Back to x143 and my filter now on a good setting, getting some lovely views of the craters and spend a bit of time looking around. Here comes a question: when my eye approaches the 7mm eyepiece I see a blue hue around the edge, it goes away when I get my eye in the right place, but reappears at the slightest eye movement - any idea what this is?

I decided to try the 2x Barlow, some good views, but the view started getting a bit "wavy", I guess that mag was too high for the current conditions.

Another question: I was struggling to focus on bright stars, I seemed to have shape pinpoint focus on the dimmer stars, but the bright ones (cappella) wouldn't come to a sharp focus, was this to do with sky conditions? I don't remember having this problem in the past.

I tried for a few more objects, but the moon was washing out most of the DSOs that I was sure I was near, the clouds were still floating around, the focusing issue, and it was starting to get cold!

All in all, when the clouds gave way, I had some nice satisfying views of the moon, but the rest of the session seemed a bit of a washout and I came back in feeling unfulfilled. To top it all off, I left the scope (mostly) set up and set the alarm early to have a look at the planets - cloudy!

Sorry to put a dampener on some nice reports, I'm sure you've all experienced these types of sessions. Let's not get downhearted. Winter is coming, the clouds will go away on an evening when the moon is less than 50%, the nights now start at 6pm.

My best session is still to come. (thanks for reading)

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The best is always yet to come! Just gotta keep at it, although sometimes motivation can be hard to find.

What scope do you use? If it is an achromatic refractor, which I use, then the blue fringe is chromatic abberation. It shouldn't be present in any kind of reflecting telescope or an APO refractor. It is worse in fast scopes (f/5 or 6ish) and unless it is severe, you'll just have to put up with it.

High magnifications magnify everything including any optical defects or poor seeing conditions. I had poor seeing last night so kept the mag to below x150.

You're right about the Moon though, it's always really cool!

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Don't worry, we all have nights like that, even after years of observing. Whilst I had some nice views last night, they were hampered by dew, I was away from home and didn't have any dew heaters with me. In addition it's the first time this season I've got cold and I didn't have any warmer clothes with me so I packed in relatively early and enjoyed the extra hour in bed [emoji3]

As you say, there will be plenty of nights when things go well.

Stu

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I've got a Sky watcher 200P, f/5 Newtonian. Like I said, it disappears when I get my eye right in the cup, but is quite sensitive when I try to look around the view and it flickers in and out. I don't have the same issue with my 18mm.

Oh yeah, forgot about the dew and my finder scope fogging up.

I'm quite happy with the fact that my best session will always be in the future, and my next "best session" will only ever be my "current best session". I'm still starting out and finding my way around, so it can only get better.

Thanks for the support.

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I totally sympathise with you mate....last night I set up waited a while for the scope to acclimatise...went back out and the corrector plate was completely dewed up (even with a dew shield on)...I soldiered on determined to have a quick imaging attempt...aligned the scope and attached the camera to the rear cell of the nexstar 4se...slewed to M31 and the camera decided to stop the process as it was hitting the base of the mount (well done Celestron good thinking on that arrangement !!! )...undeterred I swapped things around...fitting a diagonal to the rear cell and the camera into the eyepiece holder on the top of the scope...problem solved objects high in the sky could now be reached....slewed round to M31 ...all good so far...scope started to track M31...excellent so far...pressed the shutter release and the battery indicator started flashing red....stood back looked at the telescope dripping with dew....had a quick sulk then put it all away and went inside and had a beer....... :sad:  :mad:

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After a number of years observing I have a rough plan but mostly expect the unexpected and not feel bad if things don't work out. The fog has a strange habit of rolling in around midnight, most nights around here so you have to learn to take it in your stride....

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I like your way of thinking Mr Spock.

Thanks Peter, I may just do that. I have been meaning to head up your way for a while now. Do you have group viewing sessions? For some reason I was under the impression that you just had 1 big telescope in a dome - don't know why.

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when I say "group session", I meant a group of individuals bringing their own scopes, rather than an organised group of people attending the centre.

But i'll find a nice Saturday night and come on over, see what you've got going on. Cheers. Hopefully see you soon.

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Hi rockystar, thanks for the taking the time to post. There are a lot of good reports on here about great sessions, but not so many about when it goes wrong. Made for a refreshing read. Keep your chin up. This one will make the good sessions stand out even further.

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Here comes a question: when my eye approaches the 7mm eyepiece I see a blue hue around the edge, it goes away when I get my eye in the right place, but reappears at the slightest eye movement - any idea what this is?

Color around the Moon edge is transverse chromatic aberration (or latteral colors) from eyepiece.  Lunar limb is a very tuff night sky object for testing latteral colour, though the latteral colour can be easily seen in daylight when pointing you scope to bright sky and looking at the field stop. Lateral colors are very common among wide angle eyepieces (cheap or expensive), some epieces showing red color should show worse latteral colors than the ones showing blue.

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