6 replies to this topic

[bokemon]

Hello folks, 

I currently have an iOptron HAE29 Alt-Az strain wave mount, which I use with many scopes, up to a C9.25.  For visual sessions, i either use an eyepiece or binoviewers, and then a guide scope / camera + sharpcap + stellarium to do plate solve and goto.  With this, I can easily view planets, clusters, split some doubles, etc.  There are really only two drawbacks to this setup:

1) somewhere between iOptron / Ascom / Stellarium, the software is still kind of buggy and sometimes an accidental disconnect is really hard to fix and requires rebooting, restarting, or just a lot of wasted time.

2) I wonder how stable it really is to hold a large scope by just one dovetail, cantilevered out there.  When a car or train rolls by (approx 200 yards away) I can see microshakes at high power.

 

Therefore I wonder if just having the fork mount would be a better setup.  (I'm thinking of the 8" ACF on sale at Highpoint.  If I end up choosing a 10" instead, then it probably will be fork mount, or buy a Warp Astron)  No, I will not do long exposure imaging on this setup.  At most a few minutes worth of EAA live stacking.

Also, want to confirm if this mount can do resync from Sharpcap?  I need this in order to center doubles or anything at very high magnification.

Aside from being able to talk in a retro voice, would there be any other features that could be of interest to me?

Thanks

[VMan]

No answers but curious about the same thing. I currently have an LX90 fork mount from a Meade 12" LX90 that I am hoping will be "good enough" for a 200mm multi scope setup for Astrophotography. (I simply can't handle the combined weight of the 12" OTA on the fork without tweaking my back, and have been using the 12" on an AM5). I have a GMTec miniPC and am successfully communicating with the fork mount.... but I have yet to get it polar aligned and tracking. Still waiting on a clear night....  

[carolinaskies]

The LX90 is reasonable for the light duty you describe.  It's not 'rock solid' compared to the LX200 with good field tripod.  Though a good tripod is really essential for any mount.  I find this is one area mount buyers skimp on trying to save money or weight.  A decent tripod has enough weight and leg diameter to dampen most shakes as well as good spreader bar and solid feet.  Remember the mount and OTA are more weight off-center sitting on top several feet in the air.  

EAA pretty much was built around the Alt-Az platform for ease of setup and getting to the imaging quick.  

The LX90 8-12" all have the same base with just the arms themselves canted for the width of the OTA.  So for limited AP it can be made to work somewhat, but I'd suggest an LX200 with it's beefier fork arms.  

[VMan]

The LX90 is reasonable for the light duty you describe.  It's not 'rock solid' compared to the LX200 with good field tripod.  Though a good tripod is really essential for any mount.  I find this is one area mount buyers skimp on trying to save money or weight.  A decent tripod has enough weight and leg diameter to dampen most shakes as well as good spreader bar and solid feet.  Remember the mount and OTA are more weight off-center sitting on top several feet in the air.  

EAA pretty much was built around the Alt-Az platform for ease of setup and getting to the imaging quick.  

The LX90 8-12" all have the same base with just the arms themselves canted for the width of the OTA.  So for limited AP it can be made to work somewhat, but I'd suggest an LX200 with it's beefier fork arms.  

Thx for the info. Indeed I was surprised that once I had the OTA removed I could noticeably flex the fork arms a bit relative each other, leading me to realize that the OTA itself, with it's beefy base, provides rigidity to the fork, simply by reducing independent movement in the individual fork arms. It leaves me a little concerned how this will perform on a wedge, definitely a more favorable design for Alt/Az.  I also noticed that the arms that connect the back of the OTA to the fork axis are not in fact perfectly parallel, so the original design when assembled has some tension in it, but not in a way that impedes dec rotation. Clever engineering. If I can get everything behaving in a promising way I'll have to put some thought into the support brace that will connect the two fork arms that my scope array will sit on.... at the moment I just machined an oak board to fit between the arms and drilled a hole in the middle to connect a guide scope too... I should take a picture... it looks absolutely ridiculous 

[carolinaskies]

Thx for the info. Indeed I was surprised that once I had the OTA removed I could noticeably flex the fork arms a bit relative each other, leading me to realize that the OTA itself, with it's beefy base, provides rigidity to the fork, simply by reducing independent movement in the individual fork arms. It leaves me a little concerned how this will perform on a wedge, definitely a more favorable design for Alt/Az.  I also noticed that the arms that connect the back of the OTA to the fork axis are not in fact perfectly parallel, so the original design when assembled has some tension in it, but not in a way that impedes dec rotation. Clever engineering. If I can get everything behaving in a promising way I'll have to put some thought into the support brace that will connect the two fork arms that my scope array will sit on.... at the moment I just machined an oak board to fit between the arms and drilled a hole in the middle to connect a guide scope too... I should take a picture... it looks absolutely ridiculous 

There are a few examples on CN others have done with the LX and Celestron forks making adapters between these forks.  Some of them did a drop 'U' so the center of the telescope was more in line with the DEC axis.  

[bokemon]

Does the Lx90 mount experience micro shakes at high mag due to the stepper motors or gearing?

[carolinaskies]

Does the Lx90 mount experience micro shakes at high mag due to the stepper motors or gearing?

No, the gearing doesn't cause shakes.  Shakes typically are produced by wind or movement around the mount due to heavy footfalls.