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Has anyone tried a EdgeHD 8" on an SE type mount?

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#1 Eddgie

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Posted 26 August 2013 - 04:43 PM

I know that the EdgeHD 8" is a few pounds heavier than the standard C8, but I am hoping to go to an 8 SE type mount.

Has anyone tried this?

Thanks!

#2 dragonslayer1

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Posted 26 August 2013 - 05:07 PM

have heard just the std C8 is very prone to vibration on single arm side mount is all. Never had one tho.
Kasey

#3 Cliff Hipsher

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Posted 26 August 2013 - 08:41 PM

OK, let me get this straight... You want to put a $1200.00 astrograph quality SCT on a $500.00 "One Armed Bandit" Alt/Az mount?

If its a budget thing, save a little longer and at least get one of the new VX mounts...

#4 jrbarnett

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Posted 26 August 2013 - 09:27 PM

The saddle jaws on the SE mount are for a V-series dovetail. If your Edge has a D-series dovetail, you'll also need an adapter, which will move the center of gravity away from the centerline of the mount and also add more weight. Personally I'd not bother with a standard C8 on that mount, though they sell them that way. I think the C6 is just about perfectly matched for the mount's (and primarily, it's tripod's) capabilities.

Now if you were to put the SE head on the CPC tripod...which you can do; the two are "pin compatible"...then you might have a reasonably stable setup.

Regards,

Jim

#5 Tin_Can_Man

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Posted 27 August 2013 - 04:51 AM

Hi Edggie

I have both a 6se and an Edge HD 800 (purchased last sale due to your outstanding acclamation of the ota) . Granted I had a shorty feather touch crayford on the Edge, but when I tried it, it certainly sounded as if the mount struggled a little. If you do your best to lighten it perhaps it will perform better. If you like I can try a barebones ota on the se mount when I get a bit of spare time on the weekend.

#6 Eddgie

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Posted 27 August 2013 - 07:05 AM

Were the motors stuggling, or was it struggling with stability?

#7 Eddgie

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Posted 27 August 2013 - 10:21 AM

If you do get a chance to try it, please let me know.

My configuration would be the OTA, Telrad, 1.25" diagonal, and Mark V binoviewer. The Mark V and 2" diagonal, and 24mm ES 68 eyepieces weight about 10 oz more than a 2" diagonal and 31mm Nalger.

Clearance is not an issue because the Mark V configuration is shorter than the 2" diagonal by quite a bit.

If you can do this, I would apprecate your feedback.

Thanks!

#8 John Miele

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Posted 27 August 2013 - 12:52 PM

Hi Edggie,

I run an Edge 8 scope on the Nexstar 8SE mount. My configuration is the OTA, a green laser pointer, a 2" SCT style diagonal and EPs up to a 31mm Nagler.

The motors do not struggle whatsoever and the goto and tracking accuracy are excellent.

Stability is the issue (vibration while focusing). I leave the tripod as low as possible for seated viewing and I use VSPs. This keeps the shakes pretty managable up to 120X with my 17 Nagler. Above that power requires a steady hand to focus and you have to wait for shakes to die down as you tweak towards best focus. An electric focuser would fix that but I don't have one.

The magic of the Nexstar mount is it is very lightweight and can be set up in minutes and carried outside in FULLY ASSEMBLED with ease.

You trade stability for portability. If you don't feel that is a worthwhile tradeoff, I would not recommend it.

My shorter SCT style diagonal (had to buy and adapter and md the one I orignally had) clears the base fine at Zenith if I move the scope forward on the mounting rail.

I ended up making two spacers under my mounting rail to allow proper seating and to be able to slide the scope forward as much as I liked.

This link has some pics and other reports I posted on the Nexstar users forum. It covered a lot of ground but you can probably find the items that interest you pretty quickly.

http://www.cloudynig...5840664/page...


Hope this helps...John

#9 Eddgie

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Posted 27 August 2013 - 01:14 PM

Hi John.

Perfect. Exactly what I was looking for.

Do you think that the vibtation on the tripod is mostly because of the tripod?

Is the tripod the same as used on the new CG5 ASGTs. If not, do you know if it will fit?

I have a CG5 ASGT that I would sell, and perhaps I could just trade out the tripods and sell the CG5 cheaper. With a light weight tripod, it would be a great Go-To for a 4' refractor.

I did not realize I would have to shim it to get clearance. I am using a Losmandy V series dovetail.

Have you run the scope off of AA batteries before? If so, how long does it run?

Perfect info though.. Just what I am looking for.

The scope will only be used with a Binoviewer and my binoviewer sits very close to the rear cell so I don't anticipate any clearance problems.

I don't use the scope much for planets. Mostly low power and medium power sweeping and larger, brighter clusters.

The vibration does concern me a bit though, but only a bit. I would use the tripod in the lowest configuration I am sure.

Anyway, if you have that info, I appreciate it, and your answer was exactly what I was looking for.

Thanks again...

#10 Eddgie

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Posted 27 August 2013 - 01:22 PM

Here is the configuration I hope to use... I will actually be 5mm closer in the back when I go to the Baader 10mm connector.

I don't anticipate any clearance issues.

Attached Files



#11 dragonslayer1

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Posted 27 August 2013 - 02:10 PM

Am curious now,,, you have the C8 on a CG-5 ASGT and want to put it on a SE and get rid of the CG-5?? If that is correct, do you have a problem with it on your CG-5? Just curious, thank you
Kasey

#12 Eddgie

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Posted 27 August 2013 - 02:20 PM

There are several reasons.

First, I don't image so I don't need a GEM.

Next, the 8SE will run of internal batteries so I can do a quick session without cables.

And finally, it is light and compact so it will travel easily on road trips. I can put it into the storage well at the back of my hatchback and not worry that it can be seen from outside the car (I can take the OTA into the hotel at night). No counterweight or counterweight shaft.

But here is the main reason. I am going to go to a very short connection from my Binoviewers. It is the Baader 10mm SCT to T2 connector. This connector cannot be rotated easily. It is a "Semi-permanent" connection method.

Because of this, I can't use this on a GEM because I can't rotate the diagonal. The optimal solution would be an Alt-Az mount where it is not necessary to tilt the binoviewer one way or the other.

#13 John Miele

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Posted 27 August 2013 - 02:22 PM

Hi Eddgie,

Do you think that the vibtation on the tripod is mostly because of the tripod?

I think it’s a mix of the cantilevered single arm and the tripod. There are several threads on the Nexstar forum about people upgrading tripods and achieving noticeably better stability results but still not anything like a “Rock of Gibralter”!

Is the tripod the same as used on the new CG5 ASGTs. If not, do you know if it will fit?

Sorry. Do not know.

I did not realize I would have to shim it to get clearance. I am using a Losmandy V series dovetail.

I also use Losmandy V series dovetail. It will work without shims, but if you try to slide the OTA too far forward (and you may need to to clear your diagonal) the SE mount runs into the top of the Losmandy provided radius blocks. My spacers go between the top of the radius block and the dovetail and that lest is slide much further forward into the SE mount. If you look carefully at the pictures you can sort of see what I mean.

Have you run the scope off of AA batteries before? If so, how long does it run?

I have, but never more than an hour or two. I did not run the batteries dry but have read that it will drain them pretty fast. I ended up just taking them out of the base and always run off of an 18aH 12V battery. I can run the scope for several hours over multiple nights with no issue.

NOTE: The SE mount power cord has a bad habit of jiggling free from the mount connector. I carefully spread apart the prongs just a little and it fits much more snugly. But I also always wrap a Velcro band around the power cord to keep it from pulling out as the scope slews.


I don't use the scope much for planets. Mostly low power and medium power sweeping and larger, brighter clusters.

The vibration does concern me a bit though, but only a bit. I would use the tripod in the lowest configuration I am sure.

If you stay at lower powers and use anti vibration pads, I do not think focusing shakes will bother you much at all.


John

#14 dragonslayer1

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Posted 27 August 2013 - 02:40 PM

Good reasons, have you ever looked into badder click lock's. Hope all ges well for you, Kasey

#15 Eddgie

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Posted 27 August 2013 - 03:07 PM

Are you talking about this?
Baader Clicklock visual back

Or this:

Baader Clicklock diagonal


The Baader Clicklock SCT to 2" visual back has to much light path length. Costs me about .2 inches of aperture over the SCT to 10mm visual back and adds about 60mm of focal length.

The Baader Clicklock diagonal that allows the nose to be removed and the mirror box to be screwed on to the SCT threads is pretty short, and would allow me to convert to a 2' eyepiece holder and 2" eyepiece, and I have considered this, but once again, it is not as short a light path as the T2 Prism and 10mm SCT connector and again, I think about .3" aperture loss and 90mm focal length increase vs. the T2 Prism and 10mm connector.

I can't find the exact specs for the Baader Clicklock diagonal though, but most 2" diagonals have a light path of about 70mm though the mirror box itself and not including the eyepiece holder (which I don't use because the Binoviewers connect directly to the mirror box).

So, the Baader Clicklock diagonal is a little long and the Clicklock is more light path than I need too.

There really isn't a shoreter light path than the 10mm connector and T2 diagonal. The Clicklock adapter is much longer light path.

#16 dragonslayer1

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Posted 27 August 2013 - 03:11 PM

I see you are all over the options already,,, just thought was another route to go.
Kasey






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