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Skywatcher Esprit 150 ed (Socal)

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#1 astroflak88

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Posted 12 January 2020 - 03:56 PM

Do any of you own a 150 ed? I'm thinking of buying one but I'm not sure yet. I would like to compare it with my achromat and I'll decide from there. I live in socal and willing to meet you before I decide to buy one. Thank you

#2 astroflak88

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Posted 13 January 2020 - 11:57 PM

This scope is 32 lbs. If an equatorial mount's payload is 30 lbs will 2 lbs of additional weight really be an issue?

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#3 Cometeer

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Posted 14 January 2020 - 03:55 AM

This scope is 32 lbs. If an equatorial mount's payload is 30 lbs will 2 lbs of additional weight really be an issue?

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Generally with equatorial mounts, you don’t actually want to be close to payload rating - especially for imaging. For visual, it would probably introduce a lot of vibrations. If you were to use a 30lb SCT, it might be manageable since all the weight is concentrated near the moment arm of the mount. But with a long 30lb refractor, the distribution of weight means you will want to over mount it for a satisfactory experience. Eyepieces, diagonal, finder, etc might add another 5lbs too. I’d be looking for mounts that have a 60lb payload rating. Stay away from the 30lb mount classes such as the AVX. 



Any reason for wanting an EQ mount? With such a long scope, you might find yourself observing from uncomfortable angles at times. I’d prefer to use an alt-az mount such as the DiscMounts DM6.


Edited by Cometeer, 14 January 2020 - 04:01 AM.


#4 Bomber Bob

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Posted 14 January 2020 - 06:53 AM

My APM 152ED (plus Tak FC-50) rides smoothly on a restored 1980s Meade StarFinder on a 5' pedestal:

 

APM ED 152 S076 (Meade SF Restore).jpg


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#5 astroflak88

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Posted 14 January 2020 - 09:47 AM

Generally with equatorial mounts, you don’t actually want to be close to payload rating - especially for imaging. For visual, it would probably introduce a lot of vibrations. If you were to use a 30lb SCT, it might be manageable since all the weight is concentrated near the moment arm of the mount. But with a long 30lb refractor, the distribution of weight means you will want to over mount it for a satisfactory experience. Eyepieces, diagonal, finder, etc might add another 5lbs too. I’d be looking for mounts that have a 60lb payload rating. Stay away from the 30lb mount classes such as the AVX.



Any reason for wanting an EQ mount? With such a long scope, you might find yourself observing from uncomfortable angles at times. I’d prefer to use an alt-az mount such as the DiscMounts DM6.

How about for an alt az manual mount (no goto function) that has a 30 lb payload like the twilight ii? If I buy the 150 ed will 2 lbs over the payload be a problem?

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#6 nva

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Posted 14 January 2020 - 10:48 AM

Don't undermount that's a large, heavy, scope with a significant moment arm.

Edited by nva, 14 January 2020 - 10:55 AM.

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#7 ezwheels

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Posted 14 January 2020 - 11:44 AM

For visual, I would look for a mount rated about 45lbs minimum. For AP I would be running an EQ mount with a rating of 55lb minimum only if it was at least a SB or Astro-Physics or 10u or other high precision mount where they are rated for imaging and not simply just capacity to move to load.


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#8 Bomber Bob

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Posted 14 January 2020 - 12:15 PM

For visual, I would look for a mount rated about 45lbs minimum. For AP I would be running an EQ mount with a rating of 55lb minimum only if it was at least a SB or Astro-Physics or 10u or other high precision mount where they are rated for imaging and not simply just capacity to move to load.

IIRC, the StarFinders were rated at 50#, and I made improvements to the pedestal to dampen vibrations.  BUT, the only imaging I do with mine is planetary -- AVIs no longer than 5 minutes.  I would not attempt serious DSO imaging with the rig posted above.

 

When I want 0 (zero!) vibrations, I put the 152 on my 1940s Tinsley pedestal EQ.  The mount weighs 212#, HUGE bearings disk on the polar axis, and 0 backlash.  If I upgraded / added precision stepper motors to both axes, it would be observatory class.  It has no trouble carrying the 28# OTA rig as pictured:

 

APM ED 152 S073 (Tinsley Mount).jpg

 

(Since this pix, I repainted the pedestal glossy gray.)


Edited by Bomber Bob, 14 January 2020 - 12:25 PM.

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#9 coopman

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Posted 14 January 2020 - 02:11 PM

Refractors get big & heavy very quickly as their aperture increases. I always wanted a 6" refractor. Then by the time that I got one I realized that it was too heavy for me to safely handle it.

Edited by coopman, 14 January 2020 - 02:12 PM.


#10 tonyt

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Posted 14 January 2020 - 08:30 PM

For visual use you could go with the 150ED doublet which weighs a lot less (and costs a lot less) and rides easily on an EQ6 class mount. There's no obvious CA in focus and the figuring seems quite good.

 

The Esprit should also be ok on the EQ6 though, but with an improved tripod.

IMG_2767.JPG

 


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#11 Bomber Bob

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Posted 14 January 2020 - 10:33 PM

This scope is 32 lbs. If an equatorial mount's payload is 30 lbs will 2 lbs of additional weight really be an issue?

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That sounds too high.  My APM 152ED bare OTA (no rings, no dovetail) is ~ 19#.  I bolt its hinged rings directly to a thick aluminum plate (that's part of the EQ mount).  Adding the Bresser ring assembly + Tak FC-50 w/cradle gets it up to 26#.  A heavy scope, but a 50# capacity mount carries it well enough for steady views at 400x.

 

These scopes are nose-heavy, which is why I add the Bresser stuff & Tak -- puts the eyepiece higher in the cradle.  And I enjoy using the tiny fluorite APO.  Just as important is Balance.  If it's off too much, the motor won't track well.



#12 aa6ww

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Posted 15 January 2020 - 12:04 AM

The Esprit is a beautiful refractor. Its shorter then a 6" F/8 like my APM-152 but its also over 30% heavier so I would definitely not go with anything smaller then a CGX size mount for stability. 

 

I believe a mount like the CGEM Pro with the heavy duty tripod may be acceptable also, but definitely not with the stock wobbly tripod. I've used a C11 on a CGEM and it was not very stable. The moment the focuser was touched, the scope shook. Thats a 30 pound OTA thats much shorter then a 150 Esprit F/7.

 

I think you would destroy a mount like the AVX with something this large. The plastic teeth on the gears would probably snap off fairly quickly and Id question the longevity of the motors, especially at the moment the scope first started to move when the most torque is applied on the motors. I would be worried something would break or come lose and your scope would come crashing down.

 

In my case, I use a Losmandy G11 and it works beautifully and is very solid, but I would not trust the smaller GM8 Heavy Duty mount for such a beast as your 6" Esprit.

 

 ... Ralph

Attached Thumbnails

  • 152 on G11.jpg

Edited by aa6ww, 15 January 2020 - 12:05 AM.

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#13 dscarpa

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Posted 15 January 2020 - 02:19 PM

 I tried my overweight C9.25XLT- it has a 80mm and red dot finders and WO Crayford-  on my Twilight II and it worked quite well with 3lbs as a counterweight on the empty arm. What makes putting a scope on most alt az mounts a lot harder than a GEM is your working side saddle.  There's no way I'd do that with a large scope  on a regular basis unless I had help. My scopes stay on their mounts which are all alt az. David




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