108 replies to this topic

[Moondust]

Moondust

 

The 80EDL is no more unstable on my ES Twilight I mount than my Orion ED80 is. And my Orion ED is stable on that mount. For my purposes and reasoning, I don't know that the EDT needs to be chosen with this class mount.

 

I'm just saying my 80EDT being a shorter more compact scope is noticably more stable at 160x than my SV80 f/7 Access. At low to medium power the difference could go totaly unnoticed. I do quit a bit of lunar observing and 160x with the 3mm setting on the Tele-vue zoom is the norm. It's a joy to be able to fine focus the EDT at that power without any hint of vibration. I used a SV80 Access and 92mm Stowaway on the same modified Porta Mount 2 with homemade wooden tripod and the 80EDT plus my AT60ED are the only two scopes I would classify as rock sold on that mount. Perhaps your Twilight/ tripod combo are more stable than my Vixen mount. I'm in the process of getting a more substantial mount to support a larger scope, perhaps an AT102 EDL or AT115 EDT but still want to keep it rather grab and go if at all possible. 

[Jon Isaacs]

I'm just saying my 80EDT being a shorter more compact scope is noticably more stable at 160x than my SV80 f/7 Access. At low to medium power the difference could go totaly unnoticed. I do quit a bit of lunar observing and 160x with the 3mm setting on the Tele-vue zoom is the norm. It's a joy to be able to fine focus the EDT at that power without any hint of vibration. I used a SV80 Access and 92mm Stowaway on the same modified Porta Mount 2 with homemade wooden tripod and the 80EDT plus my AT60ED are the only two scopes I would classify as rock sold on that mount. Perhaps your Twilight/ tripod combo are more stable than my Vixen mount. I'm in the process of getting a more substantial mount to support a larger scope, perhaps an AT102 EDL or AT115 EDT but still want to keep it rather grab and go if at all possible. 

 

I have a Vixen Portamount with Wooden legs.  My 80mm F/7 WO FD seems very solid and I am a doubles guy so I go over 300x with it, the 3.5 mm Nagler plus a 2x Zoom.  I also have an AT-80LE, it is a carbon fiber 80mm F/6 FPL-53 doublet.  I don't see a difference between them in terms of stability and vibration on the Portamount.  Of course not all wooden legs are created equally.  

 

Jon

[Moondust]

I have a Vixen Portamount with Wooden legs.  My 80mm F/7 WO FD seems very solid and I am a doubles guy so I go over 300x with it, the 3.5 mm Nagler plus a 2x Zoom.  I also have an AT-80LE, it is a carbon fiber 80mm F/6 FPL-53 doublet.  I don't see a difference between them in terms of stability and vibration on the Portamount.  Of course not all wooden legs are created equally.  

 

Jon

Maybe I just need to invest in a premium tripod. Any suggestions? 

[Scott in NC]

I use a Berlebach Uni-18 with my smaller scopes.  Here’s a picture with a TV85 and DM4 mount riding on it.  But to stay on topic, this tripod would be perfect for the AT80EDL or EDT.

 

 

 

[wrvond]

I'm just saying my 80EDT being a shorter more compact scope is noticably more stable at 160x than my SV80 f/7 Access. At low to medium power the difference could go totaly unnoticed. I do quit a bit of lunar observing and 160x with the 3mm setting on the Tele-vue zoom is the norm. It's a joy to be able to fine focus the EDT at that power without any hint of vibration. I used a SV80 Access and 92mm Stowaway on the same modified Porta Mount 2 with homemade wooden tripod and the 80EDT plus my AT60ED are the only two scopes I would classify as rock sold on that mount. Perhaps your Twilight/ tripod combo are more stable than my Vixen mount. I'm in the process of getting a more substantial mount to support a larger scope, perhaps an AT102 EDL or AT115 EDT but still want to keep it rather grab and go if at all possible. 

I had my AT80EDL on a Twilight 1. With a 'D' plate, Baader 2" prism diagonal and Plössl equipped Quark, there was noticeable vibration though it settled fairly quickly. However, I've replaced that mount with a dual axis drive equipped CG-4. Sadly, this meant I had to change back to a 'V' plate but I now have a much sturdier platform with tracking and the controls are easier for me to reach/operate.

The TW1 is a very compact mount - so compact that I found it virtually impossible to operate the focuser without bumping up against the 'D' plate/shoe or clutch lock. The new setup is substantially heavier than the TW1 setup, I think, but still easily carried in one trip.

[Jon Isaacs]

Maybe I just need to invest in a premium tripod. Any suggestions? 

 

What wooden legs are you currently using?  I bought mine from Gary Hand at Hands on Optics.

 

I really love the Portamount, the OTA being set back from the tripod is just so comfortable. I recently realized I was using my 80 mm more than my NP-101 because I preferred the ergonomics of the Portamount to the StellaVue MG-2, it's version of the SkyTee mount.

 

The SV-MG 2 uses a surveyor's tripod so just this week, I did some work and mounted the Portamount on the MG-2 tripod. I had about 45 minutes with it, it seems like it will be stable enough to use with the NP-101.. 

 

 

 

I don't know much about surveyor's tripod  but the one I'm using doesn't appear be more than about $100, it's worth looking into.

 

Jon

[Moondust]

Thanks for all the suggestions, but we'd better not dwell on mount/tripod subject or the feds will be in here moving posts. Once I decide on a beefier mount though, I will be set and can even get a AT115 EDT if it should suddenly go on sale.   

Edited by Moondust, 30 December 2022 - 10:59 AM.

[Scott in NC]

Kenny, would you (or anyone else who has an AT80EDL) mind showing me a picture of the part of the rings that connects to the dovetail rail? Even just a picture of the rings themselves will do.  

 

In the Astronomics ad, it looks like that part of the rings has a raised section which places a cm or two of distance between the dovetail rail and the OTA.  If so, I really like that feature, as it not only minimizes the chance that the rail will scrape against the dew shield, but it also decreases the chance of damaging the paint on the OTA by using overly long screws to connect the rings to the rail.

[KWB]

Scott

 

Will this do or do you need me to dismantle the rings from the dovetail bar to see the bottom of the rings?

 

[Adluginb]

I think he is wanting to know the distance between the dovetail and the Ota.  Maybe take a pic from the end and not the side so that you could see how far the tube sits above the dovetail?

[Scott in NC]

I think he is wanting to know the distance between the dovetail and the Ota.  Maybe take a pic from the end and not the side so that you could see how far the tube sits above the dovetail?

Yes, that’s what I really wanted to know, but I think I can see it well enough from Kenny’s picture.  It looks like if an overly long screw is used to attach the dovetail rail to the ring, the tip of the screw shouldn’t come in contact with the tube.

[KWB]

Here's an image of the bottom of the ring.

 

[Scott in NC]

Thanks, Kenny—I appreciate that!  I like the way those rings are designed.

[Scott in NC]

Now I see that my former AT125EDL had similarly shaped rings, as I just found a picture of it that I had taken to show someone else who was asking me about them.

 

 

 

[wrvond]

I think this is what you're trying to see:

 

[KWB]

Is this the money shot?

 

Short screws were included to attach the rings to the bar.

 

[Scott in NC]

Yes!  That’s exactly what I wanted to see, Warren and Kenny.

 

In contrast (although it’s hard to tell from this picture, but it’s the best one that I have), the rings that came with my former AT80ED didn’t provide much elevation between the dovetail rail and the OTA.  As a consequence, I ended up putting small circular marks in the paint on the tube when I tried to switch out the stock Vixen rail to a Losmandy plate.  That wouldn’t have happened had the rings been designed the way they were for the AT80EDL.

 

 

[KWB]

Scott

 

What mount is that under the AT80ED?

 

Does it have slow motion controls?

 

It looks very nice. 

[Scott in NC]

Thanks, Kenny.  It’s a Stellarvue M1, which I don’t think has been produced for several years now.  It doesn’t have slow motion controls, but is smooth enough that I’ve never felt the need for any.  It’s pretty similar in size, shape, and function to the UA MicroStar, which is also no longer being produced.

[Jon Isaacs]

The photos that Warren and Kenny provided are interesting. I like that design as that gap provides visibility and protection since the threaded hole is not drilled through.

 

I wonder how much that ring set and dovetail weighs? 

 

I have an AT-80LE. It's a carbon fiber 80 mm F/6 FPL-53 doublet. The bare bones scope weighs slightly less than 5 lbs but the heavy duty rings and dovetail weigh 1.5 lbs, negating any advantage the carbon fiber offers. I'm trying to work out a lightweight solution.

 

Jon

[HagglePig420]

I dont have either of the 80s, but I do have a 102EDL and a 130EDT. I find both are very good for the price, both have sharp optics and good color correction, Though the 130 is a triplet, I actually think the 102 doublet has slightly better correction with it's better glass. I use the doublet far more for imaging and it has basically no detectable CA. I imagine the 80EDL would preform just as well.

[wrvond]

 

The photos that Warren and Kenny provided are interesting. I like that design as that gap provides visibility and protection since the threaded hole is not drilled through.

 

I wonder how much that ring set and dovetail weighs? 

 

I have an AT-80LE. It's a carbon fiber 80 mm F/6 FPL-53 doublet. The bare bones scope weighs slightly less than 5 lbs but the heavy duty rings and dovetail weigh 1.5 lbs, negating any advantage the carbon fiber offers. I'm trying to work out a lightweight solution.

 

Jon

 

I’ll check.

[Jon Isaacs]

I’ll check.

 

 

Jon

[wrvond]

Complete set up is 32.7 ounces:

 

Sans handle is 28.8 ounces:

 

Ring only is 8.1 ounces:

 

Each screw weighs 0.1 ounces X 3 screws:

[wrvond]

The bar weighs 12.1 ounces:

 

And the handles weighs 3.7 ounces: