Show Posts

This section allows you to view all posts made by this member. Note that you can only see posts made in areas you currently have access to.


Messages - rackramasca

Pages: [1] 2 3 ... 9
1
Quote
That's sort of a lateral with an upward trend kinda thing. New, on a level playing field, I'm going with the Losmandy, but you're in an obsy, already set up, and your iEQ45 Pro is working pretty well. If you're not throwing out subs (which I found you don't really do with the 45's, generally), you're not going to get much more from the Losmandy. BUT, if you're changing something, like going for really long subs in narrowband, and you're finding the 45 can't cut it, then you might try the Losmandy. Losmandys are kinda that middle ground between the best of the Chinese-made and the real step up: the big boys like AP, Bisque, and then the exotics like 10Micron and ASA.

I've gotten similar imaging results from both 45's and Losmandys, with the Losmandys being much better looking.

Paul

A fair and reasonable assessment I think! If you are happy, keep taking pictures, if you want something a little more, then Losmandy makes a good, solid mount worth considering.

JMD

JMD

2
Beginners Forum / Re: A dad that needs some advice from the gurus.
« on: February 09, 2018, 10:18:16 AM »
Father of three boys here. Get something you are comfortable with them using themselves. Looking at things you've found gets boring fast. The reward of finding and seeing an object themselves makes a much more significant impression.

3
I have a Celestron 94115-A diagonal that is a prism. Weirdly, the Agena page states that this is a mirrored diagonal, but other sites still state it's a prism. You might want to check on one of these.

4
General Astronomy & Observing / Re: Top things to obeserve in the sky
« on: February 09, 2018, 04:32:06 AM »
Don't forget the Moon -- and Saturn when it becomes reasonably well placed before dawn in another month or two. I would say that those are indisputably the two most spectacular telescopic targets in the sky.

The Moon is constantly changing as the shadows shift -- even during a single session if you look carefully. That makes it the gift that goes on giving.

5
When I was 17, I started an 8", and got frustrated. The next year I did a 6" f/8, but never tested it, much less parabolized it. It worked out well for my purposes at that time. Maybe I got lucky, maybe a f/8 is very forgiving. Ended up giving it away to a kid who was interested. Wish I had it again. Oh well.

That said, I can't imagine doing a 16" by hand. Even a full thickness 12" would be too heavy to work by hand IMHO. If nothing else I would fear dropping the thing.

6
Eyepieces Questions & Recommendations / Re: Lumicon UHC Vs DGM NPB
« on: February 08, 2018, 10:02:50 PM »
Quote
I thought that there was a problem with the UHC based on a thread that I can no longer find. It's possible that it was about the OIII not the UHC, and I remembered wrong.

This might be the thread (now locked):https://www.cloudyni...ii-scan-report/

It was the O-III, and it wasn't based on hearsay, but the report sent by Lumicon along with the filter in question.

7
Yes, we're all going to need some luck on this. Unfortunately, probably about 30% of us are going to be clouded or rained out of the event. Counting on odds of cloud cover and heading a thousand miles may not end up being the right decision. In the end clouds can form on any given day at any given location. It's kind of like playing the lottery. Does buying 100 tickets significantly improve your odds of winning over someone who bought just one? Find a nice spot, relax, and enjoy the day.

8
ATM, Optics and DIY Forum / Re: Silvering Primary Mirrors
« on: February 08, 2018, 05:46:47 PM »
Quote
<p class="citation">Quote
If I recall, it's a somewhat dark precipitate. It can be an extremely sensitive explosive.

Only when dry. It's OK in solution. This was pointed out in ATM Book I.[/quote]
Right around where the stopper/lid is, you can have enough built up there to ruin your day. I've seen this stuff "at work" and it indeed can be treacherous.
M.

9
Reflectors Telescopes Forum / Re: Zhumell Table-top Dob Series
« on: February 03, 2018, 01:27:17 PM »
Quote
Note that only the 5" Zhumell has rings, which allow you to rotate the tube.


Yeah I like that too Steve. Makes it easy to move to another mount regardless of the orientation of the saddle.

10
Good posts, Don, as always!

It seems that dielectric diagonals, 2" or 1.25" are more popular than prisms. Going by the selection available. Roland's comments seem to indicate lesser quality with the dielectrics, especially for detail views, if I read it correctly.

This has always been an area of confusion for me.

11
Reflectors Telescopes Forum / Re: Primary mirror "imperfections"...?
« on: February 02, 2018, 06:15:07 PM »
Quote
Here are two more pictures with 2 of the blemishes nearly centered. One blemish has a greenish flaring around it. The other looks something what a pellet might do to a window. As I change the angle of the camera slightly you can see the "pellet" blemish simply moves up and get slightly brighter, but the flaring on the other blemish begins to get larger.

I also found an edge flattened in one spot along the already beveled edge.

Totally off-topic but your first two photos remind me of what we are seeing on Ceres.

12
Reflectors Telescopes Forum / Re: Meade Lightbridge 10" truss dobsonian
« on: February 02, 2018, 01:37:54 PM »
Quote
Quick question I'm hoping a LightBridge 10 owner can answer - how long is the lower optical tube assembly? Thanks!

About 16-1/2" including the collimation knobs. About 17-1/4" with Farpoint weights attached.

13
Beginners Forum / Re: Orion Sky Scanner 100 Telescope?
« on: January 31, 2018, 09:08:10 AM »
Quote

I have both the twilight 1 and a Port amount. The Portamount is the better mount of the two, I think the Twilight 1 is actually heavier but the Portamount is the more stable of the two, fewer vibration issues.

Jon

14
Eyepieces Questions & Recommendations / Re: Explore Scientific 92 17mm
« on: January 31, 2018, 06:48:11 AM »
Quote
Any more user reports on these? The few that are out are pretty great. I would love to hear if someone compared this with an E17.
I plan to get one or the other to use witha type1 Paracorr on a 12" f/5. I'm not big on detailed reports so general impressions are fine.

shock when I get my first look of the night. Nothing else out therecomes close.

The weight of theEP is an abomination. But I have learned to live with it. It closely matches the weight of my ES 30mm 82°, and my moonlite focuser seems up to the task. For balance purposes,I had to slide my refractor up the tuberings, but that ended up being a blessing because I am now seated a little further from the ground while observing the zenith.

I would like to thank Explore Scientific for producing this extraordinary eyepiece.

I am EAGERLY awaiting the release of the reported ES8.8mm 92°.

15
Reflectors Telescopes Forum / Re: Parabolic Primary vs Spherical Primary
« on: January 31, 2018, 05:17:19 AM »
There's quite a world between "noticeable errors" and "sucks". If you want the latter, just buy a 130mm f/5 telescope that is too cheap for a good mirror (I did so -- the tube was the one Celestron was at that time putting on their 130SLT. If it was parabolized, then they certainly had called it quits almost immediately...needless to say, I returned it).

So, "so-so" would be f/7.7, and f/5 is definitely "sucks". f/6.9 is somewhere in between.

Pages: [1] 2 3 ... 9