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iOptron's HP RA worm upgrade kit. PE Results.

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#1 Astronewb

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Posted 29 August 2013 - 12:20 AM

I recently received and installed iOptron's high precision worm upgrade kit for the iEQ45 mount.

I had previously installed Abec 7 worm bearings, so I wasn't expecting any huge gains. The kit was relatively easy to install, remove old worm and bearings, install new worm and larger worm bearings. Total install time took about 35-40 minutes, and I took a lunch break during the install.

There was supposed to be a fine pitched pulley and belt kit available as well, but for some unknown reason, it never materialized. More on that later.

I ran some PE tests using Telescope Drive Master as a recorder, with the guide cable disconnected so only raw PE was recorded. The installation of the high precision worm and bearings resulted in a reduction of 8 arc-seconds over the standard worm.

Testing was done with a 90mm ota, electronically balanced on the mount. Testing was done indoors, no wind, with the mount tracking on M31 as a simulated target.

Since it's rainy and cloudy, I did some 'inventificating' with the fine pitch pulley concept. The stock iEQ45 pulleys and belt are 3.0mm pitch, the ZEQ pulleys and belts are 2.0 mm pitch, much more rigid, and less flex on the cogs.

I installed a set of Z mount fine pitch pulleys, with the motor pulley modified to fit the iEQ45 shaft, and calculated and sourced a proper length belt. When I installed these to the iEQ45, it reduced the periodic error to 7 arc-seconds, peak to peak. (No PEC used)

Here's a link to some side by side comparison graphs captured from the TDM TE Recorder:

http://www.flickr.co...57635275957079/

What's really impressive is the smoothness of the graph with the fine pitch system and the low RMS value.

Hope this is helpful to some iEQ45 owners and imagers looking for the best solution for their mount.

Clear skies all,

Paul

#2 whwang

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Posted 29 August 2013 - 05:21 AM

That's really impressive. Thank you for posting this. Let's hope the fine pitched pulley and belt kit will be available soon.

#3 KGoodwin

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Posted 29 August 2013 - 08:32 AM

The 2013, 8000D model of the iEQ45 seems to come with the high precision worm stock, but does not upgrade the pulleys or belt to fine pitch versions, right?

#4 Astronewb

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Posted 29 August 2013 - 11:13 AM

The 2013, 8000D model of the iEQ45 seems to come with the high precision worm stock, but does not upgrade the pulleys or belt to fine pitch versions, right?


That's correct, but it does not have the fine pitch pulleys or belt.

I just this moment heard from iOptron, they are shipping me the iEQ45 pulleys with a different tooth design to test.

They indicated the difference in the pulleys would be apparent, and an improvement, but with the same number of teeth?

I wont have any specific details until the pulleys arrive and will post an update then.

It is refreshing to see a mount company actually offering updates to existing equipment.

Regards,

Paul

#5 timmbottoni

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Posted 29 August 2013 - 07:38 PM

Hi Paul,

I have the new gear and the original pulleys, and used the bearings that came with each. I have been trying to do testing and compare the new to my old. I am using the software called PHDLab v.0.4.3 to analyze my files and have a 50mm guidescope and an old Meade DSI. I balanced my setup and didn't try to be East heavy, and I tried different areas of the sky, and I didn't really keep track of which areas produced the results, but I could probably figure it out if I went back and looked at the pics I tried to take.

Assuming I am reading it correctly, the old worm had a native PE that ranged from about 45 arc sec, to about 60 arc sec.

The new worm has a native PE that ranges from about 6-15 arc seconds.

Does that seem like sensible results?

It guides much easier as well, but I think I'm actually overguiding now and will set the guide rate back to .5 on the next attempt. My stars all show a slight elongation, in RA, which is very consistently displayed.

Hoping for some really good nights of seeing soon, because I was having trouble with my guide stars beeping, on a 2 second loop. I'm still very much a newbie at all this though so thanks for your help and patience.

Timm

PS. I also hope to try recording the PE and testing the PEC function soon as well.

#6 Astronewb

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Posted 30 August 2013 - 10:57 AM

Assuming I am reading it correctly, the old worm had a native PE that ranged from about 45 arc sec, to about 60 arc sec.

The new worm has a native PE that ranges from about 6-15 arc seconds.

Does that seem like sensible results?

It seems sensible to me Timm. My iQ45 originally had about 40 arc-seconds of PE.

I tightened up the gear train and installed Abec 7 bearings at the worms and got it down to about 20-24 arc-seconds.

Installing the HP worm and bearing kit from iOptron reduced that considerably, to about 16 arc-seconds.

The fine pitched belt and pulleys turned the mount into a real performer along with the HP worm.

As far as guiding, unless your pulse guiding with EQMOD, I would leave the guide rate at 1.0, and adjust for guiding overcorrections by reducing the RA Agg, or Mx RA settings in PHD. Just play around in 10 step increments and observe the affect on your graph.

If you want to get rid of the bleep, set your star mass to .9 or higher in the advanced settings (brain), that bleep is really annoying...:)

If you consistently have elongated stars in RA (vertical trailing) then perhaps it's time to check your polar scope alignment to make sure it's aligned to the mount axis?

All the best, clear skies..

Paul

#7 Darren Bly

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Posted 30 August 2013 - 03:13 PM

The 2013, 8000D model of the iEQ45 seems to come with the high precision worm stock, but does not upgrade the pulleys or belt to fine pitch versions, right?


That's correct, but it does not have the fine pitch pulleys or belt.

I just this moment heard from iOptron, they are shipping me the iEQ45 pulleys with a different tooth design to test.

They indicated the difference in the pulleys would be apparent, and an improvement, but with the same number of teeth?

I wont have any specific details until the pulleys arrive and will post an update then.

It is refreshing to see a mount company actually offering updates to existing equipment.

Regards,

Paul


Thanks for that info. I was planing to get an 8000D but I can wait for the updated belts and pulleys.

Darren in Bakersfield.

#8 timmbottoni

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Posted 30 August 2013 - 03:13 PM

Thanks Paul,

I have checked my polar scope - its dead on. I have also used the Polar Alignment feature which seems to act sort of like the Alignmaster 30 day demo I tried. I might buy it - its cheap. My elongation is in RA and I really think I'm actually overguiding now.

Timm

#9 Astronewb

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Posted 31 August 2013 - 12:20 AM

Thanks Paul,

I have checked my polar scope - its dead on. I have also used the Polar Alignment feature which seems to act sort of like the Alignmaster 30 day demo I tried. I might buy it - its cheap. My elongation is in RA and I really think I'm actually overguiding now.

Timm


If your polar alignment is on the money, you probably are overguiding a tad?

Have you ever used the Two Star alignment routine? After the 2 star, the HC will tell you how far off your polar offset is, in arc minutes. For example, if it says 12 higher and 8 west, then you would need to lower your alt by 12 arc minutes and move the mount east by 8 arc minutes using the mount lat and az adjusters.

Then do another Two Star routine to see how far you've chipped away at the polar offset? The bullseye overlay in PHD helps there, each circle is about 8 arc minutes and it makes it easy to get to '01-01' or '00-00' in about 3 to 4 iterations.

If you get to 01-01, you can typically image for 3 minutes unguided. If you get to '00-00', five minute unguided images are possible.

If you use that routine and then turn the autoguider on, PHD will thank you for it...:)

Regards,

Paul

#10 timmbottoni

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Posted 31 August 2013 - 11:46 AM

Have you ever used the Two Star alignment routine? After the 2 star, the HC will tell you how far off your polar offset is, in arc minutes. For example, if it says 12 higher and 8 west, then you would need to lower your alt by 12 arc minutes and move the mount east by 8 arc minutes using the mount lat and az adjusters.


I upgraded my HC so it has the Polar alignment feature now, and the multistar alignment. I have used the built in Polar alignment and I'm really not sure if it helps or not. The polar scope gets it really close, and my DEC drift wasn't very much, and it easily guided that out.

I downloaded the 30 day trial of Alignmaster a while back and it really seemed to work, but it expired so it may be time to buy it.

What do you think?

Thanks,

Timm

#11 Astronewb

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Posted 02 September 2013 - 09:30 AM

They indicated the difference in the pulleys would be apparent, and an improvement, but with the same number of teeth?

I wont have any specific details until the pulleys arrive and will post an update then.

Just an update, I received the new style iEQ45 pulleys. A quick exam revealed a very well finished set of pulleys, with excellent machine work.

The motor drive pulley has no flanges, but it does not need them, the flanges on the worm pulley keeps the belt centered very well.

The pulleys measured the same diameter, but I noticed one strange thing. The flat at the top of the cogs was much thinner on the new pulleys, about .70mm wide versus the 1.0 mm on the originals?

I installed the pulleys and ran some PE tests (3) with the new pulleys in conjunction with the upgrade worm kit. The results confirmed my suspicions, the PE actually was worse with the thinner cogs because that allows the cogged belt to 'walk' back and forth on the pulley.

I posted the best result to the iEQ45 Periodic Error test here:

http://www.flickr.co...57635275957079/

I'm hoping that this particular set of pulleys was a error in manufacturing, because there is no way I could recommend using them over the original pulleys.

Cheers and thanks for looking,

Paul

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#12 rkayakr

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Posted 02 September 2013 - 02:44 PM

I believe that in the upgraded software you gain the polar alignment but lose the report of polar error after alignment.

#13 timmbottoni

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Posted 05 September 2013 - 07:43 PM

Testing mine again tonight. I will post results once I have them figured out.

Timm






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