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Messages - ifaclidis

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How did you attach the safety line to the mirror and holder?

Did you use the same silicone that you glued the mirror with to bond the safety line to the back of the mirror and holder?

It would seem that if the silicone that held the mirror failed then it would also fail with the safety line.


I did not use the same adhesive, I either used epoxy or cyanoacrylate.

Jon

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Reminds me of a few childhood rhymes... "Fatty & Skinny went to bed.....", or the always fond "Mutt & Jeff" remarks

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Eyepieces Questions & Recommendations / Re: New TS UWA 4mm
« on: February 09, 2018, 04:08:42 AM »
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Great. Did you find the eye relief comfortable enough to take in the FOV ?

George

I found myself drawn quite close to the lens to appreciate the full FOV and my eyelashes scraped frequently against the rubber eyeguard when blinking. I don't know if this is a sign that the advertised eye relief is possibly a bit exaggerated. Usually I don't have such problems with Plossl and other short eye relief EPs. Maybe it's just the eyeguard design. At any rate my impressions are positive and there are no many ultra wide eyepiece available at this price. A good benchmark would be to pit this EP against the ES 4.7mm but I don't have it; it's the closest in terms of price, features and focal length.

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That split view is pretty effective. I suppose the amount of shift in the bands could be translated into quantitative slope errors. Photo 2 in the top row and 1 in the bottom seem to be the most sensitive. I wonder if there is any need for the others.

I have no idea how to go from those differences to a plan for correction (not that this mirror needs any). With the Foucault programs, you can get a diagram of the surface deviations across the middle which seems more helpful.

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Do the Morpheus eyepieces equal the Delos and the XW in sharpness and detail?

I didn't think so but others I know do in fact like them as much or better than the XW's/Delos.

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I never saw any UFO but I did hear something that to this day I can't properly identify. I was deer hunting one day in the early 90s near my parents home in southern Illinois. It was daylight and dead quiet in the woods when I heard the sound of something large traveling high overheard. It passed from horizon to horizon in just a couple of seconds. I was within the trees so I couldn't see the sky. I'm an engineer so I have a bit of training to think about it logically. I could tell from the sound that the object was large, and it was unpowered. There was no sound from any type of propulsion. It was not a bullet, I know what those sound like whizzing by. There was no sound of a shot being fired nor a sound of the object landing anywhere around. I'm a veteran and have spent a few years downrange from artillery and that was what it was like. It really sounded like a large round going overhead. Something like a 16 inch gun but without the report or concussion of impact. I'll never forget that sound passing overhead. I stood in the woods for half an hour digesting the information and trying to figure out what it was.

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Eyepieces Questions & Recommendations / Re: More Televue
« on: February 08, 2018, 06:06:53 PM »
List the telescopes you own or plan to use with the TeleVues.

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Eyepieces Questions & Recommendations / Re: glow in the dark
« on: February 03, 2018, 10:19:41 AM »
thanks guys,the ones that I still have say astronomy-shoppe.com , but when I go there I don't see any thing close to what i have .

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I bought my WHITE from a UK retailer, and i am happy it was available and cheaper than Orion a lot, and the shipping was fine too, so congratulations on your white, you are my brother now, hehehehe

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Thank you to all for the reality check. I think I will go for the low hanging fruit for now. I baffled and blackened everything in the scope, I'm going to move the cooling setup higher on the to do list, get some thinner guide vanes and then leave it as is for this summer. I'll shelve the dual secondary idea as my next winter's project.

Cheers all, thanks again for your thoughts!

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Light Pollution Topics / Re: Washington State Legislation Attempt on LP
« on: February 02, 2018, 09:21:22 PM »
Mike you are probably right re; less effective to emphasize a small beneficiary group when the energy saving aspects of the bill are really the most significant--and something everyone could get behind. Wasting energy (and what is more *wasted* than energy used to light up the sky?) seems like the best angle to take on this i think.

In this vein, cities like Grand Rapids and Ann Arbor, MI are going to LED for their municipal street lighting.  The use of LED fixtures garners ~50% energy savings over sodium fixtures and bulb replacement only offers a ~20% savings (the difference is lost by absorption through the less efficient old fixture lens). LED lighting has the added &amp; inherent advantage of <em class="bbc">better directionality resulting in less light diffused to the sky.
 LED STREET LIGHTING PILOT PROJECT REDUCES ENERGY USE BY 80% (Ann Arbor)

 Tell us how you like energy-efficient streetlights (Grand Rapids)

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Looks like the best thing to cure a back ache.----Dave

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I have the partsnow - just need some time to put things together.

Pat

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Beginners Forum / Re: Meade Starfinder 10
« on: January 31, 2018, 09:23:32 AM »
Reply to post 7291537 by Alex McConahay

Hi Alex: Thanks for your advice.

It was for a 14 year old boy in town. I did let it go for $135. He came over with his dad and was all excited.

Peter

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Beginners Forum / Re: Idiot needs help with collimation
« on: January 31, 2018, 08:20:30 AM »
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My Orion StarBlast 6 has the same mostly-plastic 1.25" focusser as the one on your XT4.5.   I know the focusser all too well...focusser5.jpg
Synta considers it de rigueur for the smaller Orion and Celestron branded Newtonians that they manufacture and market.
I really don't think it's ideal for testing the collimation of a laser collimator, for where the eyepiece is inserted there's a good deal of slop, among other substandard "features".
I see what you mean. I noticed the slop, too, not that you mention it.
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This is how to properly collimate a laser collimator, and with the three grub-screws recessed into the unit's body...http://www.nightskyi...collimation.htm
You can get those parts in the plumbing department at Home Depot or Lowe's.  I'll be doing that myself when I decide which laser collimator I want for myself.
I'll check out that video. It may be the one, or similar, that I saw yesterday that shows making a "vee" with PVC pipe elbows and tees. I'm going to make one of those.<p class="citation">Sky Muse, on 15 Aug 2016 - 09:38 AM, said:<a href="https://www.cloudynights.com/index.php?app=forums&amp;module=forums&amp;section=findpost&amp;pid=7378468" rel="citation">[/url]<blockquote class="ipsBlockquote built" data-author="Sky Muse" data-cid="7378468" data-time="1471246729">
In so far as the Orion laser unit, I wouldn't get a second one, as it doesn't look as though it can be easily rotated within a vee block.  Get a refund, and get one of these instead, and each with the body and the nosepiece at the same 1.25" diameter...http://www.scopestuff.com/ss_lcol.htm
I can't really say which one of those two would be best to get.  If research proves fruitless, then flip a coin.[/quote]
I already have the replacement Orion unit on the way, otherwise I would take your advice right now. I'll give it a try but if it's not collimated, or I can't get it to sit in the vee properly, then I will send it back and get the refund. I do most of my shopping through Amazon because I have Prime. Sometimes things like those lasers are made by one factory but marketed by different brands. I'm wondering if this is the case here. I found this one:
VITE Laser Collimator 1.25'' Metal with 2" Adapter and Battery 7 Bright Levels for Reflector Telescope Collimation https://www.amazon.c...i_EtMSxbDSA9A88
It looks similar to one of those you linked to.<p class="citation">Sky Muse, on 15 Aug 2016 - 09:38 AM, said:<a href="https://www.cloudynights.com/index.php?app=forums&amp;module=forums&amp;section=findpost&amp;pid=7378468" rel="citation">[/url]<blockquote class="ipsBlockquote built" data-author="Sky Muse" data-cid="7378468" data-time="1471246729">
Don't neglect to get the Celestron Cheshire tool.  You're going to need the cross-hairs for aligning the secondary mirror under the focusser.  The laser unit won't help in that regard.  The Cheshire is also a lifetime tool.  You'll never need to buy another one.  You can use it for that 8" or 10" Dobsonian in future.[/quote]
Done. I ordered that exact Cheshire tool earlier today. Thank you for that advice.<p class="citation">Sky Muse, on 15 Aug 2016 - 09:38 AM, said:<a href="https://www.cloudynights.com/index.php?app=forums&amp;module=forums&amp;section=findpost&amp;pid=7378468" rel="citation">[/url]<blockquote class="ipsBlockquote built" data-author="Sky Muse" data-cid="7378468" data-time="1471246729">
"With the offset the way it is, do I adjust that with the three little screws?"
It will be a combination of adjusting the three set-screws, the larger center screw, and the spider-vanes if necessary, and as I had described earlier.
Again, did you take the second, bottom photograph through the wide focusser opening, or through a pinhole eyepiece similar to the collimation cap?  If the latter, then you need to move the secondary mirror back towards the front opening of the telescope, and with the secondary center-screw by turning it clockwise.[/quote]
I took it looking straight down the wide focusser opening. I apologize for not answering that last time.<p class="citation">Sky Muse, on 15 Aug 2016 - 09:38 AM, said:<a href="https://www.cloudynights.com/index.php?app=forums&amp;module=forums&amp;section=findpost&amp;pid=7378468" rel="citation">[/url]<blockquote class="ipsBlockquote built" data-author="Sky Muse" data-cid="7378468" data-time="1471246729">
This is the reason why you need the Cheshire.  A sight-tube with cross-hairs is integrated within the Cheshire tool, and for centering the secondary mirror directly under the focusser.[/quote]
Okay. I will take a look when mine gets here.<p class="citation">Sky Muse, on 15 Aug 2016 - 09:38 AM, said:<a href="https://www.cloudynights.com/index.php?app=forums&amp;module=forums&amp;section=findpost&amp;pid=7378468" rel="citation">[/url]<blockquote class="ipsBlockquote built" data-author="Sky Muse" data-cid="7378468" data-time="1471246729">
This may be of help... http://www.schlatter...y/collimate.htm
There are links within that link to investigate as well.[/quote]
Thanks, I'm going to read through that stuff. I started looking at the beginning of that article with the equipment for collimating already. He sounds like I feel a little bit!<p class="citation">Sky Muse, on 15 Aug 2016 - 09:38 AM, said:<a href="https://www.cloudynights.com/index.php?app=forums&amp;module=forums&amp;section=findpost&amp;pid=7378468" rel="citation">[/url]<blockquote class="ipsBlockquote built" data-author="Sky Muse" data-cid="7378468" data-time="1471246729">
"They don't really explain how those screws work to move the mirror."
They simply butt up to the backside of the secondary mirror's holder, and tilt the mirror into alignment with both the focusser and the primary mirror...secondary washers-screw2b.jpg
To adjust one screw, you have to adjust another, and the other, and all three until you tilt the mirror into near-perfect alignment.  A Newtonian can never be collimated 100% perfectly.  It may be possible, however, to produce one that could be, but I'd have my doubts.[/quote]
Oh my goodness, that makes sense! I thought the screws pulled the mirror, but I see now that they push! That's partly why I'd didn't get it. Do you tighten those screws down once the mirror is aligned? I am under the impression that you should snug them up so that they won't come loose. I realize you don't use much torque at all too tighten them, but it almost seems like that isn't really necessary.<p class="citation">gnowellsct, on 15 Aug 2016 - 10:16 PM, said:<a href="https://www.cloudynights.com/index.php?app=forums&amp;module=forums&amp;section=findpost&amp;pid=7379357" rel="citation">[/url]<blockquote class="ipsBlockquote built" data-author="gnowellsct" data-cid="7379357" data-time="1471292202">
I guess I would add that "Idiot needs help," though it may be an honest statement about how one feels, is actually not helpful.  First of all, even to be attempting collimation already places one outside the idiot class.  Second of all, some of us (myself) had to be taught three or four times before "getting it," especially for Newtonians, and we do not volunteer to be brought into the dumbkopff class merely because we passed through a necessary phase, any more than being awkward one's first six months behind the wheel is something to feel bad about.  Newts have many more adjustments than SCTs.  And third of all, and perhaps most critically, it may contribute to a feeling among other newcomers that if they ask basic questions they are viewed with disdain, which runs counter to the mission of this forum; and actually, all the fora in CN.
I would suggest something like "Doh!  Need help with collimation" is a far milder form of self-deprecation (if it is needed at all) that keeps a more positive attitude to the business of learning how to keep our instruments going.
Greg N[/quote]
Hi Greg, I'm sorry for my terminology. I tried specifically to not include others in my characterization. The "idiot" is me, primarily because I am nearly certain that I adjusted things that didn't need it and made my scope worse, not better. Of course, I am far from an idiot. I'm college educated, a high school teacher, possessing degrees, certifications, and credentials. I also know that making someone feel stupid doesn't help them learn. That's why I was trying to make it clear that I *feel* like an idiot and that it applies to me alone. I feel like maybe I failed to make that more explicit.
When I wrote this originally, I was very frustrated. I had just spent the better part of two hours turning little Allen screws, turning a Phillips screw, squinting down a pin hole, trying to get the red dot inside the black donut, and finally realizing I was no closer to being collimated. I had started getting irrational thoughts like I would never get it fixed, that I had broken my telescope, and that it was all my fault. So, I felt like an idiot for messing with it, particularly the center screw which probably was fine.
I'm a Language Arts teacher. I don't do math; not because I just think I can't, but because I have some kind of deficiency where numbers are concerned. Any numbers. Even time is tough for me. But, I enjoy science and astronomy is one of the subjects that has always fascinated me. Yet, things like ascension and declination leave me baffled. I am good with ideas, visuals, and words. This particular hobby sometimes leaves me feeling befuddled and confused.
I am sorry I wasn't more clear in what I said. I don't think other people struggling with collimation are idiots. I didn't mean to label anyone but myself, and not even seriously at that. I agree that by us attempting it, we are already likely ahead of the average person. I have no argument with you. If I could edit the title, I would. On the other hand, I feel there is some very good information in this thread and I know I have been much helped by it. I hope any others reading this will understand that I meant malice to none but myself and that I really was attempting to make a joke at my own expense. Thanks for helping me see it from another view.<p class="citation">spencerj, on 15 Aug 2016 - 10:46 PM, said:<a href="https://www.cloudynights.com/index.php?app=forums&amp;module=forums&amp;section=findpost&amp;pid=7379425" rel="citation">[/url]<blockquote class="ipsBlockquote built" data-author="spencerj" data-cid="7379425" data-time="1471293996">
The Chesire/sight tube combo tool that sells for $35 is great.  It works well.  It is a very good place to start and in some cases it may be all you ever need.  My comments about the Glatter lasers were more aimed towards someone who is going to drop $70-90 on a "Deluxe" laser collimator.  That person can save themselves a lot of time an needless frustration by spending a little more up front.[/quote]
I don't know how "deluxe" the Orion unit is. I just realized it was $70! I had forgotten I spent that much! Hmmm. If the new Orion unit is out of collimation, or maybe even if it isn't, I may just send it back and get the Glattner. That looks promising. I like tools that just work. It looks like you need attachments, too, though. Could run over $200, easy. Thanks for the advice. I will be thinking about that one.

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