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Update on my SW ED150 order...

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#826 Kunama

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Posted 25 August 2018 - 06:24 PM

All this talk of adding weight, lightening cells etc.... I just fit the diagonal and eyepiece then focus and finally loosen the clamshell clamp and slide the scope till it balances...... 


 

#827 CHASLX200

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Posted 25 August 2018 - 06:43 PM

Competition is good for prices, and for innovation.  Maybe S-W will look at lightening the OTA, improving the balance (my APM is very nose-heavy) -- sky's the limit.  If these sell well, other companies will join the mix, and that's even better.

Most all 6" and biggers scope are top heavy. My 6" AP F/9 was very top heavy and i hate having tubes loaded low in the rings. So i added a extra ring at the focuser end with 5lbs to keep the tube higher up in the rings.  In the cheaper 6" ED's the focuser is lighter weigh so it will be top heavy.  I plan to add another ring with a weight when i get my SW150ED..  Or just add a big and heavy finder to balance it out. My AT 72ED with a 2" Ethos will be more than enough for bottom end weight and i can have the tube way up in the rings.


Edited by CHASLX200, 25 August 2018 - 06:45 PM.

 

#828 roadi

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Posted 25 August 2018 - 06:58 PM

  Maybe S-W will look at lightening the OTA, improving the balance (my APM is very nose-heavy)

The dew shield adds considerable to the nose heavyness. Just discovered this while dealing with an issue with the Apm. The tensioner screw on the dew cap ring will easily dent and scratch the ota paint if tightened just a little to much. I made a tiny teflon piece to put in the threaded hole in front of the screw. So to other owners, be aware!!


Edited by roadi, 25 August 2018 - 06:59 PM.

 

#829 LewisM

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Posted 25 August 2018 - 07:34 PM

All this talk of adding weight, lightening cells etc.... I just fit the diagonal and eyepiece then focus and finally loosen the clamshell clamp and slide the scope till it balances...... 

Couldn't have said it better Matt.

 

Is there a need to reinvent the wheel, or over-complicate a totally simple concept?


 

#830 Tyson M

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Posted 25 August 2018 - 09:38 PM

Jim,

 

I can vouch as well for the focuser on my SW72ED.

 

Skywatcher changed their focuser design and the new ones are simply sublime. I will call mine slightly inferior to the 2" Crayford FTF but definitely better than a Tak stock focuser, Sharpstar 2.5" R&P and GSO 2-speed Crayford in terms of "feel", having had / have all the other focusers on various scopes as well.

That's interesting. On a newer 2017 SW120ED its stock focuser was very good, but still a tiny bit behind the sharpstar rack and pinion. The latter being the best stock focuser I have used on a scope (2" version I had though).


 

#831 mogur

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Posted 25 August 2018 - 09:41 PM

Couldn't have said it better Matt.

 

Is there a need to reinvent the wheel, or over-complicate a totally simple concept?

Yes but then you need a mount that's 6 feet tall. Unless you like sitting on the ground to view anywhere near zenith.


 

#832 nicknacknock

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Posted 26 August 2018 - 01:53 AM

That's interesting. On a newer 2017 SW120ED its stock focuser was very good, but still a tiny bit behind the sharpstar rack and pinion. The latter being the best stock focuser I have used on a scope (2" version I had though).

Tyson,

 

It is much smoother than the Sharpstar R&P. I have no illusions that the R&P has a higher weight bearing capacity than the tiny Crayford on my SW72ED, but it is significantly more coarse in use. The SW72ED focuser can easily handle a 2” diagonal and Nagler T5 31mm by the way, and that’s good enough for me ;)

 

Jim,

 

Does your experience echo mine re the new unit you received?


 

#833 MortonH

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Posted 26 August 2018 - 02:45 AM

Couldn't have said it better Matt.

 

Is there a need to reinvent the wheel, or over-complicate a totally simple concept?

 

Before observing with a long scope I spend a couple of hours digging a hole underneath it to sit in.  This keeps the eyepiece at a nice height, keeps me sheltered from any breeze and means I don't need to find a bathroom.


 

#834 starman876

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Posted 26 August 2018 - 05:52 AM

All this talk of adding weight, lightening cells etc.... I just fit the diagonal and eyepiece then focus and finally loosen the clamshell clamp and slide the scope till it balances...... 

That is all I have ever done.  As long as the  tube is balanced on the mount that is what counts.  Does not really matter where the tube sits, just has to be balanced.


 

#835 CHASLX200

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Posted 26 August 2018 - 07:04 AM

I hate low loaded OTA's with top heavy lens.  I will add weight to my SW150ED with a extra ring and a few lbs of weight.  Really don't need a finder since i never view many DSO's.


 

#836 Jon_Doh

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Posted 26 August 2018 - 09:44 AM

The dew shield adds considerable to the nose heavyness. Just discovered this while dealing with an issue with the Apm. The tensioner screw on the dew cap ring will easily dent and scratch the ota paint if tightened just a little to much. I made a tiny teflon piece to put in the threaded hole in front of the screw. So to other owners, be aware!!

On the newer ones the tension screw is teflon tipped.


 

#837 hfjacinto

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Posted 26 August 2018 - 09:46 AM

On the newer ones the tension screw is teflon tipped.


Another reason to never be the first to get a new product. Continual improvement
 

#838 daquad

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Posted 26 August 2018 - 10:23 AM

Competition is good for prices, and for innovation.  Maybe S-W will look at lightening the OTA, improving the balance (my APM is very nose-heavy) -- sky's the limit.  If these sell well, other companies will join the mix, and that's even better.

Nose heavy seems to be the bane of all large fast refractors, triplets and doublets alike.  Look at the Celestron 6" f/8 achro -- definitely nose heavy.  No way to change that, other than adding additional weight to the focuser end.


 

#839 daquad

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Posted 26 August 2018 - 10:28 AM

JW, The weight is in the glass and cell, make the rest lighter and it will be more nose heavy. Add weight to the backplate and focuser and the whole scope becomes heavier and others would complain about that. I would stick on a larger finder (11x70) and add a weight at the focuser end or upgrade to a heavier larger focuser to balance it out if thats an issue. And use a 31 Nagler. Or get classical and add a sliding counterweight. 

To be honest, they should just add a few pounds to the eyepiece end, whats a few pounds between friends? If 5 pounds more is to much for the mount, then it is under mounted as is. 6" refractors are not meant to be a grap and go scope, unless you eat a lot of spinach or have a pier and mount set up in the yard with a cover.

 

I use my 6" f12 on a pier more than my 110mm f7 on a AVX being it is easier and faster to get observing. Just uncover mount and stick on OTA, add eyepiece and turn on switch. Ready to observe.

Exactly what I do with my APM, except I don't leave the electronics outside.  Added a  pair of Parallax rings to hold the 12X60 finder and a vixen dovetail to act as a handle at the focuser end.  


 

#840 Paul Morow

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Posted 26 August 2018 - 11:01 AM

Exactly what I do with my APM, except I don't leave the electronics outside.  Added a  pair of Parallax rings to hold the 12X60 finder and a vixen dovetail to act as a handle at the focuser end.  

Me too!

 

Only 5-minute setup and take down all year round. This summer I have observed a lot during the work week with the planets on parade. Six inches of unobstructed aperture with wonderful high contrast images.

 

Life is good.

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  • Mount_AP800eq.jpg

Edited by Paul Morow, 26 August 2018 - 11:02 AM.

 

#841 Bomber Bob

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Posted 26 August 2018 - 11:20 AM

I evened-out my APM152 by attaching a vintage Pentax J60 (60x700) OTA with its 6x30 finder & bracket to the hinged rings.  Rather than moving the 152, I slide this smaller rig back/forth as needed to keep the eyepiece at a comfortable height.  The J60 is a very good achro, and the comparisons are interesting, too.


 

#842 25585

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Posted 26 August 2018 - 01:31 PM

I just hope Skywatcher got it right and gets the packing problem resolved.  The astro world needs good quality low priced refractors; the competition at the lower price point pulls the competitor in line thereby widening consumer choice.  All too often we don't have competitive markets and what we the consumer gets are higher prices with lower quality and poorer service.  So my hat's off to SW for taking a swing at this price point.

Perhaps a suitably interiorally padded casket is what is needed. The shape might get more respect, the scope might get more protection.

 

Cue Django (original movie) introduction....

 

Short term solution is to order at and buy from a nearby dealer. Inspect, try out, take along others, don't pay in advance (though a deposit may have been needed), and certainly not the balance until you are entirely happy. 


 

#843 roadi

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Posted 26 August 2018 - 02:24 PM

Another reason to never be the first to get a new product. Continual improvement

Yes one would assume but I recently bought mine, 2 weeks ago and obviously got an older model shrug.gif 


 

#844 Jeff B

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Posted 26 August 2018 - 08:57 PM

Most all 6" and biggers scope are top heavy. My 6" AP F/9 was very top heavy and i hate having tubes loaded low in the rings. So i added a extra ring at the focuser end with 5lbs to keep the tube higher up in the rings.  In the cheaper 6" ED's the focuser is lighter weigh so it will be top heavy.  I plan to add another ring with a weight when i get my SW150ED..  Or just add a big and heavy finder to balance it out. My AT 72ED with a 2" Ethos will be more than enough for bottom end weight and i can have the tube way up in the rings.

And i do exactly the same thing.  I use a separate ring for the finder and a counterpoise weight to offset the torque the finder puts on the tube.  My bino-viewers add to the balancing act as well.

 

My old AP  6" F9 weighs in at ~ 32 pounds as shown, ready to view.  The weight includes the dovetail and main rings so the dead lift weight to the rings is ~ 29 pounds.  That's a very easy and balanced lift for me.  Even my AP 7" F9 is configured the same way but with a bigger finder.  It comes in at ~45 pounds with a balanced dead lift into the rings of ~40 pounds. 

 

Doing that really does even out the OTA weight distributions and keeps my backside up off of the ground.

 

Jeff

Attached Thumbnails

  • Blue Tube C.jpg
  • 178 F9 B.jpg

 

#845 BarrySimon615

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Posted 27 August 2018 - 01:44 PM

Nose heavy seems to be the bane of all large fast refractors, triplets and doublets alike.  Look at the Celestron 6" f/8 achro -- definitely nose heavy.  No way to change that, other than adding additional weight to the focuser end.

The bulk of 6" f/8 achromats be it Celestron, SkyWatcher, Konus, or something else have aluminum tubes, but for some reason.....steel dew shields (instead of aluminum ones).  This slightly more than doubles the weight of the dew shield as compared to aluminum.  Some have solved the problem, and note that it is only a problem if the focuser end of the telescope sits too low for you in some orientations and/or you just do not like the way it looks.

 

So what are the solutions to get the telescope balance point at the cradle to at least evenly divide the tube length 50/50 or to maybe get about 60% of the tube showing on the objective side of the cradle and 40% on the focuser side?

 

1) New dew shield - substitute aluminum for steel, or maybe even a plastic gallon paint bucket (there is a thread that covers this conversion).

 

2) 2" diagonal instead of a 1.25" diagonal adds weight as does the TeleVue brass 2" to 1.25" adapter for the diagonal.

 

3) A third solution is to add weight inside of the rear of the tube so that the tube can be pushed forward in the cradle or rings.  While I was at it I purposely did not put extra weight directly under where the finder and bracket is.  I put extra weight 180 degrees away so that the tube would be balanced in rotation.  

 

Note - the added weights have double stick tape, which is not enough.  I held mine in place with the double stick tape but also used Gorilla Glue, and when that was cured, added JB Weld on top of that.  The grey JB Weld helps to minimize any internal reflections.

 

All of this helped to make the new balance point of the tube closer to the mid point of the tube, and in fact, even a bit closer to the focuser.  This, of course, raises the focuser end achieving a higher location when observing many objects.  While mine does not have the "lighter dew shield fix" pictured.  I did that too with a rolled sheet of Evergreen white modeling plastic sheet and that will result in being able to push the tube another inch or so skyward in the tube cradle.  Incorporate all the fixes and you will be able to push these scopes forward in the rings are cradle about 4 to 5 inches, plus you will get better rotational balance by counter balancing the finder and bracket (#3 above).

 

See the before and after photos.

 

Barry Simon 

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Edited by BarrySimon615, 27 August 2018 - 01:48 PM.

 

#846 mogur

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Posted 27 August 2018 - 04:52 PM

I wonder if all that extra weight in the tube will have a "bending" effect on it, affecting collimation. question.gif 


 

#847 CHASLX200

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Posted 27 August 2018 - 05:51 PM

The bulk of 6" f/8 achromats be it Celestron, SkyWatcher, Konus, or something else have aluminum tubes, but for some reason.....steel dew shields (instead of aluminum ones).  This slightly more than doubles the weight of the dew shield as compared to aluminum.  Some have solved the problem, and note that it is only a problem if the focuser end of the telescope sits too low for you in some orientations and/or you just do not like the way it looks.

 

So what are the solutions to get the telescope balance point at the cradle to at least evenly divide the tube length 50/50 or to maybe get about 60% of the tube showing on the objective side of the cradle and 40% on the focuser side?

 

1) New dew shield - substitute aluminum for steel, or maybe even a plastic gallon paint bucket (there is a thread that covers this conversion).

 

2) 2" diagonal instead of a 1.25" diagonal adds weight as does the TeleVue brass 2" to 1.25" adapter for the diagonal.

 

3) A third solution is to add weight inside of the rear of the tube so that the tube can be pushed forward in the cradle or rings.  While I was at it I purposely did not put extra weight directly under where the finder and bracket is.  I put extra weight 180 degrees away so that the tube would be balanced in rotation.  

 

Note - the added weights have double stick tape, which is not enough.  I held mine in place with the double stick tape but also used Gorilla Glue, and when that was cured, added JB Weld on top of that.  The grey JB Weld helps to minimize any internal reflections.

 

All of this helped to make the new balance point of the tube closer to the mid point of the tube, and in fact, even a bit closer to the focuser.  This, of course, raises the focuser end achieving a higher location when observing many objects.  While mine does not have the "lighter dew shield fix" pictured.  I did that too with a rolled sheet of Evergreen white modeling plastic sheet and that will result in being able to push the tube another inch or so skyward in the tube cradle.  Incorporate all the fixes and you will be able to push these scopes forward in the rings are cradle about 4 to 5 inches, plus you will get better rotational balance by counter balancing the finder and bracket (#3 above).

 

See the before and after photos.

 

Barry Simon 

I never thought of that trick with tire weights inside. My luck i would have one come unglued and it would hit the lens.  I know my old 1955 M160 Unitron had two weights inside the OTA.  They were also used to hold the guide scope and finder as there were threaded holes in the weights. This was before Uniclamps.


Edited by CHASLX200, 27 August 2018 - 05:52 PM.

 

#848 CHASLX200

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Posted 27 August 2018 - 05:54 PM

I know a older 20mm Nagler will help with bottom end weight.  I have plenty of fishing weights from 4 to 16 oz so i can rig something up or just buy a ring and a have a weight made to my specs.


 

#849 BarrySimon615

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Posted 27 August 2018 - 06:01 PM

I wonder if all that extra weight in the tube will have a "bending" effect on it, affecting collimation. question.gif

No more weight than a replacement FeatherTouch focuser of appropriate size.

 

Barry Simon


 

#850 BarrySimon615

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Posted 27 August 2018 - 06:05 PM

I never thought of that trick with tire weights inside. My luck i would have one come unglued and it would hit the lens.  I know my old 1955 M160 Unitron had two weights inside the OTA.  They were also used to hold the guide scope and finder as there were threaded holes in the weights. This was before Uniclamps.

Not tire weights, these are rectangular weights typically available in most hobby shops.  You can probably zoom in on the bagged weights in my photo and get the name and either find some locally or via Amazon.  Note - tire weights are not happy unless they are rotating at a high rate of speed!shocked.gif 

 

Barry Simon


 


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