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Topics - linghetade

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I had always been under the impression that the extra resolving power of increased aperture only manifests once you start increasing magnification, but the other night I was comparing the 3rd quarter moon in my 8" SCT with my 12" dob, and even at the same magnification, the 12" dob was showing enormous amounts of detail and texture that was just invisible in the 8" (despite better optics in the 8"). In neither case was I pushing magnification to either scope's limits. Seeing was good, but not great.

Is that normal or were my eyes just playing tricks on me?

ATM, Optics and DIY Forum / Protostar secondary mirror
« on: January 04, 2018, 02:28:42 AM »
I placed an order for a 2.48" Protostar sec. mirror a few days ago, used a credit card so no charge until shipped, now hoping they aren't on back order. The size is a perfect fit for my 12.5" f-4.8 build, 19.84% CO and 100% illumination over 11.8mm.Anybody ordered sec. mirror from them lately?I ordered some flocking some time back and the order was filled in about a week, hoping the same for the sec. mirror.Dane

Reflectors Telescopes Forum / Focusing Dilema with Orion XT10i
« on: December 30, 2017, 08:43:43 AM »
I must be doing something wrong!

I have an Orion XT10i that I bought used. Everything about the telescope appears to be in excellent condition.However I have trouble focusing it.

With the focuser's drawtube fully extended, I find I have to drawmost of myeyepieces out even further to bring them into focus. This can range from a millimeter or two to all the way past the undercut ring of the eyepiece. The focuser is the one that came from Orion (nothing to brag about) butI have carefully aligned it to the OTA with a laser. I have the locking screw loose.

Most of my eyepieces are 1.25" and I have the same result with the Orion 2" x 1.25" adapter that came with the telescope or with a William Optics adapter I purchased.

I'm fairly new to astronomy but I amtechnically oriented and I'm an engineer by profession.

I have collimatedthis scopeboth with partial and full offset of the secondary reflector. I wrongly assumed that full offset might help since it moves the secondary reflector away from the focuser slightly. I was hoping this would lower the focal plane slightly in the drawtube. If it did, I couldn't tell.

I have collimatedmy laser collimator to where it isspot onat aboutten meters. I generally use the Barlow'd laser method to align the primary. As afinal check Iusuallypull the Barlow out and thelaser isalwaysin the bulls eye. In other words, I'm pretty confident in the collimation.

Most of my observations with this scope have been planetary so far.

Has anyone seen this before and if so, what did you do to correct it?


ATM, Optics and DIY Forum / Centre-spotting a mirror. Tolerances?
« on: December 29, 2017, 01:15:00 PM »
I'm in the early 'back-of-the-envelope' stages of potentially doing a re-build of my Ceravolo HD 145mm f/6 Mak Newt. (A separate thread seeking more general advice will appear here shortly) Currently in a non-adjustable cell, the main mirror is not centre-spotted. I am contemplating putting the mirror in an adjustable cell....

What methods have you folks used to accurately put a centre-ring on Newt mirrors? What accuracy must I achieve for an f/6 mirror which is 145mm in diameter? Are there equations to calculate this tolerance?  Where can I buy the centre-spot thingy* itself - I like the ones that look like radiation hazard warning signs....



*use of such language shows my level of tech know-how....

Mounts Questions & Expirience / GM811 and Polemaster ... will it fit?
« on: December 28, 2017, 05:42:58 AM »
Looking at the new Losmandy GM811, from the images, it looks like the tucked motor on the DEC axis comes awfully close to overlaying the profile of the pole sight opening cap.

Does anybody know, or what's the consensus; will you still be able to use a Polemaster with the specific Losmandy G11/G8 mount adapter on a GM811 with its tucked in motors?

I know the Polemaster doesn't HAVE to be mounted on the pole sight opening, it's just a cleaner setup in my opinion.

... Bill

As the title of this thread says, really, how would my TMB / LZOS 130 F/9.2 triplet refractor fare, for visual observing, on an AP400 GTO2 mount ?

The AP400 in question is on the AP wooden tripod.

I'm using an old non-GOTO HEQ5 (similar to the Orion Sirus G) on a Berlebach Uni 28 tripod currently which is OK but I'm drawn to the much higher fit and finish of the AP400 which might be a more fitting match to my lovely TMB / LZOS 5.1 inch triplet.

Thanks in advance for any feedback

Beginners Forum / Orion XT8 Capabilities
« on: December 27, 2017, 11:59:55 AM »
What are the limits as to what magnitude of objects the scope can be seen? I have seen a few charts that reflect 13-14 this correct?

ATM, Optics and DIY Forum / Small fast reflector for small ccd
« on: December 27, 2017, 10:56:04 AM »
I built a ccd camera using a small 1/3 inch ccd sensor.
On top of the sensor, i put a 0.5 x focal reducer (this kind of focal reducers are normally screwed on the eyepieces)
This configuration works well with my celestron c8, but the FOV is too narrow.
So i would like to buy or build a small reflector with short focal lenght.
For example, something like the celestron cometron 114mm, that has 450mm focal lenght.
I would like to know if with this i can still use the focal reducer, or perhaps if i have to shorten the tube to put the ccd sensor near the primary mirror..
What do you think?
Any suggestion on where to buy small parabolic mirrors?
i.e. 114 to 130mm diameter

Reflectors Telescopes Forum / 8" Dobsonian vs. 10" Dobsonian
« on: December 26, 2017, 07:31:21 PM »
What are the advantages and disadvantages of buying an 8" Dobsonian vs. a 10" Dobsonian?  Budget isn't a constraint.  Can 1 individual move the 10" Dob?


Beginners Forum / White Light
« on: December 26, 2017, 09:47:03 AM »
Recently got curious about solar viewing and obtained a glass solar filter that matches both my 80mm refractor and 90mm cassegrain telescopes.  Saw the consumer review on Baader ASTF style filters and have ordered one for my own 102mm Cassegrain.I'm begining to worry about pixel size and wonder whether there'sa size limitation beyond the Sun's picture would be too smart to safely view.

ATM, Optics and DIY Forum / DIY ep case: upgrade time!
« on: December 24, 2017, 05:50:13 PM »
I've been using the identical DIY ep situation for almost 20 decades now (see under orange case).  I made it out of a $7 House Depot plastic sheeting and contains red LED lighting in the lid.
It has served me well and still works fine.  It's a modest size.  What I like are: glowing orange color, 1-piece plastic for water resistance.  I do not care if I place it down in a puddle!
The issue is that I do not trust the handle fully packed with thick eyepieces.  Plus, I'd like more room for a finder and star diagonal and other stuff.

Anyway, it's time for an update.  I picked up a Milwaukee plastic tool box out of HD again.  This time I splurged ... $39!!   It has a great handle, more space, and contains a weatherproof gasket for the lid.  I'll make a customized wood platform again out of 1/4" birch ply, with a new set of holes.  I'll ditch the plastic tray.  That just stops having loose stuff around that may ward off an eyepiece.  I am also planning more tasteful lighting inside the lid.  Plus, I want to add a few pulsating red exterior LEDs, so that I will see it from the dark and not trip over it.
Should be a fun project.   I am thinking maybe 12-15 1.25" holes and  six 2" holes this time.

On the lookout for ideas from other DIYers . .  Anything else to add or perform for the box?

ATM, Optics and DIY Forum / Super low-profile helical focuser
« on: December 24, 2017, 05:35:17 PM »
Came across this on eBay.  I believe that this is going to be a mighty fine focuser for the 6" f/9 Newt.

Mounts Questions & Expirience / CGX Mount
« on: December 24, 2017, 01:19:58 PM »
Not certain if that was discussed previously...

New mount is rather noisy even when idling.  Is this anything I need to be concerned about?



Beginners Forum / Newbie Intro and some questions
« on: December 24, 2017, 10:48:48 AM »
Hi All,

I've been lurking here for a couple of months now - good forum website!  Now I have a few questions I thought I would introduce myself and inquire.

The last time I used a telescope was back in the early 70's when I bought a few of the cheap toy telescopes, (possibly from a hobby shop or perhaps from Sears?) .  Anyhow, I remember being transfixed with being able to see the rings around Saturn.  Granted it actually was a small blob using a horizontal line moving thru it but it was mind blowing at the moment.

In the years since I've always wanted for a nice telescope but was unwilling to spend the money on one.  This Christmas season I discovered at a Costco advertisement a Celestron 130 EQ reflector with the additional eyepiece and filter collection, all for $150.  This was a bit lower than other sellers were promoting this for.  So I asked my wife to buy that for me for Christmas.

Have not actually had a chance to use it much due to the super cold cloud or weather cover.  Fumbled about one night out with it spent more time wrestling with the equatorial mount than anything else.  Have been reading a whole lot, books and the discussion posts here.

Yesterday evening I did step outside on the deck temporarily with my binoculars (10 x 50) and was able to find the Orion Nebula and the Pleiades cluster.  Baby steps, lol.  Too cold to haul out the extent, though I probably should have.  Maybe tonight if it is clear.

I also then did what everyone says you must never do - moved the extent under a window at our vaulted ceiling living area and spent some time taking a look at the moon.  I thought for certain I would find a lot of distortion but it was amazingly obvious.  I just wish I had a little more magnification.  Which leads me into the first of my queries:

<strong>Eyepieces and barlows</strong>
The scope came with two eyepieces
Celestron 20mm erecting and Celestron 10mm.
The eyepiece kit has
Celestron 15mm and 9mm

So I feel this gives me the following magnifications:  650/20 = 32.5x   650/15 = 43.4x  650/10 = 65x  650/9 = 72.x

Not a big fan of the 20mm erecting eyepiece since its image is straight out of all of the rest - kinda messes with your mind once you use it in order to locate a view and then change to some higher power eyepiece.  Should I replace this with a regular 20mm or something having a larger field of view?

To find more magnification for moon and possibly planets (possibly DSOs?)  Should I proceed with a 2x barlow?  That will get me to 144x together with my 9mm.  How about a 3x barlow?  Or maybe get a 2x barlow and a 5mm eyepiece?

Simply read the VITE 2x Barlow review that is presently on the homepage here.  Sounds like a heck of a bargain for $15.

<strong>Equatorial Mount Question</strong>
Once you point the EQ mount toward Polaris (little bit of estimating right now since I've trees at the manner toward the north) trying to maneuver the extent around to point at something in the sky to the south is a little bit of a gymnastics effort.  After I eventually get it pointed there afterward the eyepiece is occasionally sticking out at an embarrassing position.  Is it ok to loosen up the clamps holding the tube and spin the tube round to deliver the eyepiece back around to some more convenient location to view through?

One more thing about the EQ mount - I've tightened the screws to supposedly block the scope from moving in the two instructions unless you use the knobs on the extended springs (sorry, do not know the technical terms offhand).  On the other hand, the scope may still be moved around by hand.  Is that normal or just because I've a cheap scope.

<strong>Clubs Near Me?  </strong>
One final question.  I live in Wixom, MI.  Anyone belong to a golf club near here?  I've looked on the web but the closest one appears to be in Dearborn.

Sorry for the long post.  Anxious for start seeing a few of the websites I have been reading about.

Beginners Forum / Nexstar 8se or Skyquest xt10i...
« on: December 24, 2017, 10:24:54 AM »
Hi, recently I posted asking for information on accessories for a nexstar 8se.  I have not pulled the trigger yet on the scope and'm now seriously considering a dobsonian such as the skyquest xt10i that I can push to where the pc says (go-to or push-to are essential for me).  I could get 2 more inches of aperature for a little less money with the skyquest.

I'd like to find the planets, moon, and deep sky objects as well.

What is your vote?  Which would you buy?

I live in a suburban/rural place that I could do a great deal of seeing from my backyard (not a great deal of light pollution).  Would only go until the neighboring mountains on rare events.  I have budgeted about $1500 complete so either scope would allow me to find some accessories straight away.

When I was a teenager my first telescope I bought was a 10 inch dobsonian.  I fell in love with all the heavens with that scope!  I then bought a refractor that I really enjoyed as well.  On the lookout for a great range to get back in the hobby.  Really excited to begin showing the skies to my kids.

Thank you guys!

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