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Affordable Tripod Mounts for Onstep Steps

George Cushing
 

I agree with all that mark says. Even if you do repairs as a business, what do you have to charge for tech time? The local appliance place is $85 an hour. Our new $700 washing machine wasn't working properly. I ran the deep self-diagnosis and it found no issues. The service guy diagnoses insufficient water supply. The cause: $60 hoses that are designed to stop high flow rates in the event of failure. Service call $150. New cheap hoses $20.

You can't be in control of everything, even though I try. But at least OnStep let's me be in control of something!

Mark Christensen
 

I"d like to second what George says and add one more consideration - maintenance when you have vanishing vendors (or vanishing parts). The electronics industry moves fast and doesn't think in terms of decades of maintenance. We need to if we expect to be in this avocation for decades. I'm heading into my 6th and hopefully have a few more in the barrel.

I've fixed a couple of friends commercial mounts and getting spares is either impossible or expensive. Why? Often the design choices made by the engineers at the major manufacturers make it very hard or impossible to get drop-in parts and their supply chain doesn't provide spares. Aside from main worm gears and wheels most of the mechanical stuff can be fixed with commercial parts (bearings and the like), or a bit of machining or sheet metal work.

Electronics is another matter...I've had to fix and in some cases adapt older electronics which the manufacturers would not support, or wanted the entire 40lb mount shipped to even look at, or wanted outrageous sums (like $1,400) to replace some simple, older, electronics. That kind of quote is equivalent to telling you to go away.

If you've made it yourself you'll know how to fix it and you can make design choices that make it easier to fix.

For example, many GOTO mounts use servo motors with encoders. The astro-makers pick odd-ball gear box ratios and then things like 256 counts/per rev (64 lines) reflective encoders. 100, 200, 512 and so on are very common numbers - a dime a dozen on AliExpress. Not so for the 256 number, esp. in reflective (as opposed to transmissive) encoders. The mount manufacturers solution is to sell you a complete motor+gearbox+encoder. There are other solutions that are much cheaper but are not a drop in.

This is typical of what you encounter with commercial electronics - maybe OK with a $200 cell phone you replace every few years. Not OK with a telescope mount where the electronics is (or should be) a small fraction of the cost. Mounts last for decades, at least mechanically.  The problem is the electronics, which may not be robust and probably uses parts that are not or will not be available in a decade or less.

Another potential problem is the software - often the manufacturers farm that out and then don't get control (or understand) the source code. At least one manufacturer has a GOTO mount still for sale for which they freely admit they can not do updates to the software. And they won't provide the software to the user community. Again, fine for a piece of disposable electronics like a cell phone.

So we have to make our own plans - the manufacturers don't seem to think in terms of decades of operation and maintenance. Maybe at their price point and the size of their market they can't.

Mark Christensen
PS: I do this kind of work for friends for my amusement, I don't need the business.

George Cushing
 

I don't look at retail mount pricing often. So I was a bit shocked to see the price of a Celestron AVX is $900. Used they are selling for as little as $350. And from what I read they seem to have reliability problems. If you're involved in repair and service as I have been, you deal with folks who have spent significant sums on equipment only to face the frustration of either expensive repair parts or useless obsolete equipment. Conversions to the OnStep system, even if some of the work is farmed out, are about half the price of a commercial motor control board replacement. Moreover, it frees the user from the constraints of a product created for a mass market and permits more freedom to design for one's needs.

As a DIY product it forces the user to become involved in the design and construction of the system gaining an understanding of it. This removes the mystery of how things work for those who may not have this understanding, thus gaining experience that will help them deal with the greater world we are entering into. I'm told my new truck has over 200 sensors and microprocessors. 

Howard Dutton
 

I just hope he takes the "Celestron Astromaster 130 EQ" scope out and has some fun with it.  Take some shots of the moon and planets through it and some wide field shots with the camera on the mount OTA ring.

That's a 5" Newtonian on a little GEM.  I actually had a similar size (130mm f/5) Meade 'scope given to me and passed it on to a friend of a friend with an interest.  It had Autostar goto but probably the worst mount I've ever seen up close and personal LOL.  Still usable despite the mount and the optics were half-decent once I collimated them properly... and probably that was the first time they ever were.  I'm pretty sure the mount on the Celestron above is better and more usable even if it isn't goto.  Given that wobbly awful fork mount vs. a small GEM, I'd put my money on the GEM.

simingx@...
 

Ah, I actually was thinking along the lines of having one less item to worry about for a beginner in astrophotography :)
If one is willing to invest the time and effort to build an Onstep-ed mount, it's well worth it in the end...plus the satisfaction is something money can't buy.

Sorry if it seemed like I was suggesting throwing money at the problem, I do apologize for that.

Khalid Baheyeldin
 

On Wed, Nov 13, 2019 at 07:34 PM, Howard Dutton wrote:
So about $200, give or take, vs.. $950?  Unless there's a cheaper CEM25 I really don't see your point.
The way I read simingx's point is: something that works out of the box, and does not involve the DIY effort.
That is all good when someone has the budget, and does not want to invest time and effort in DiY.

So, in this case, I agree with Howard, as it looks like overall cost is the main factor for Debjyoti, even if it involves DIY.

Anything less than the LX70 is a waste of effort, since they will not be able to carry a load and perform with acceptable precision.

Now, whether the LX70 is available in Debjyoti's country, or will incurr exorbitant shipping and custom, is another factor entirely.

Howard Dutton
 

On Wed, Nov 13, 2019 at 03:35 PM, <simingx@...> wrote:
Not to be raining on anyone's parade, but for a beginner I suggest getting something like an iOptron CEM25. It's not that much more expensive than converting a mount after you factor in the time and heartache, plus it's guaranteed to work. 
So about $200, give or take, vs.. $950?  Unless there's a cheaper CEM25 I really don't see your point.

https://www.highpointscientific.com/ioptron-cem25p-equatorial-mount-with-1-5-tripod-hard-case-7100p-hc?utm_source=google&utm_medium=cse&utm_term=IOP-7100P-HC&gclid=CjwKCAiA8K7uBRBBEiwACOm4dwUiL0Xji2ooe5CrJrqJY1Xu2SLro4pIN2fn4tO2vhcF9W8lwn6DQhoCy1oQAvD_BwE

simingx@...
 

Not to be raining on anyone's parade, but for a beginner I suggest getting something like an iOptron CEM25. It's not that much more expensive than converting a mount after you factor in the time and heartache, plus it's guaranteed to work. 

George Cushing
 

I have a bin of CG-5s, I generally try to get $85 for the average mount. Without a tripod or counter weight. Sell about 3 a year, mostly to Eastern Europe. Even with the 11# weight I can ship them in a Large Flat Rate box. A basic tripod like the Vixen AL130 runs $35.  So I can sell one for $50 less than the close out LX70. BTW the LX70 is the mount formally known as the CG-5. The LX70 has a tripod that sells used for $125-150. Buy one, sell the tripod, get a AL130 and have a mount that will deal with a compact 20# payload for under a hundred.

Howard Dutton
 
Edited

On Wed, Nov 13, 2019 at 06:04 AM, Peter Dulowsky wrote:
IMHO EQ5 mount is the best budget option. It is sold under various names like Mon2, EXOS2 e.t.c. There are plenty of them in the second hand market. These are sturdy enough and there are 3d printed motor brackets designs available so they are easily OnStep-able.
Exactly, the LX70 I linked is an EQ5 class mount and at $200 new, delivered (here in the us,) a good option I think (for those who can get a hold of it.)  Good starter mounts, economical and sturdy enough to do some imaging with, used are ok provided it has not been abused too much.  Especially nice if you can get your hands on a used Vixen GP or SP but you might very well spend > $200 for it. :)

Peter Dulowsky
 

IMHO EQ5 mount is the best budget option. It is sold under various names like Mon2, EXOS2 e.t.c. There are plenty of them in the second hand market. These are sturdy enough and there are 3d printed motor brackets designs available so they are easily OnStep-able.

Howard Dutton
 
Edited

If I wanted a budget starter 'scope, for DSO imaging and visual use, I might consider one of these (or similar used noting the "ED" designation f7.5 80mm and positive reviews):
https://www.telescope.com/Orion-ED80-80mm-f75-Apochromatic-Refractor-Telescope/p/9895.uts

For visual use or planetary imaging adding an 8" SCT would be nice, and that's about as much 'scope as the LX70 can carry well, they can be bought used for about $200 or so.

Howard Dutton
 
Edited

That isn't a mount I would bother converting to goto it's just too low-end.  I suggest using it as-is.

If I were a beginner (on a budget) and wanted a *new* mount for goto conversion I'd probably take a shot at adding OnStep to one of these:

https://www.highpointscientific.com/meade-lx70-german-equatorial-mount-41-7100-00?gclid=CjwKCAiA8K7uBRBBEiwACOm4dx5lM8KRCWY7v3BxVcxhw--zrfN-fB-v8r0uEUTNN3aW6Ic1yI0TVxoCvwEQAvD_BwE

debojyoti.pal.007@...
 

Hi all, I purchased Celestron Astromaster 130 EQ with Motor drive. I would like to control it with OnStep. Would you please guide me in tge right path? I would use the same mount for my dslr and lens assembly.
Thank you

debojyoti.pal.007@...
 

Hi all,
I got my new telescope Celestron Astromaster 130 EQ with Motor Drive. I would like to control it with OnStep. Can anyone guide me the write path?
Thank you

Howard Dutton
 

On Mon, Nov 11, 2019 at 07:59 AM, Khalid Baheyeldin wrote:
The longer the focal length, the harder things become. Even with a 1300 mm 8 inch Celestron SCT, things are hard.
So, 2600mm is out of the question, and of course the higher focal length.
Stay below 1000mm or 800mm, and you can get good results.
Most amateurs use 500mm or 600mm, and get great shots.

Another thing is that a tele converter increases the F-stop.

So, if your zoom is originally F/5.6, it will be F/11, and requires double the exposure time (assuming everything else remains the same, aperture, ISO, ...etc.)
Remember planetary imaging too where some longer FL's are necessary.

Khalid Baheyeldin
 

On Mon, Nov 11, 2019 at 04:16 AM, <debojyoti.pal.007@...> wrote:
Vivitar 650-1300mm with multiple(3) 2x tele-converters giving me 2600mm, 5200mm and 10400mm focal lengths. Am I in the right path? Can I get high end telescope level photographs?
The longer the focal length, the harder things become. Even with a 1300 mm 8 inch Celestron SCT, things are hard.
So, 2600mm is out of the question, and of course the higher focal length.
Stay below 1000mm or 800mm, and you can get good results.
Most amateurs use 500mm or 600mm, and get great shots.

Another thing is that a tele converter increases the F-stop.

So, if your zoom is originally F/5.6, it will be F/11, and requires double the exposure time (assuming everything else remains the same, aperture, ISO, ...etc.)

Usually no one attempts astrophotography with anything that dimmer than F/8. And for serious work, it has to be F/6 or F/4.

Khalid Baheyeldin
 

On Mon, Nov 11, 2019 at 04:13 AM, <debojyoti.pal.007@...> wrote:
I am willing to convert a normal tripod mount "SIROI SH-15 tripod" to a goto system with OnStep. Any suggestions are welcome.

First, the term "tripod mount" is not used within the amateur astronomy community, and does not mean anything.

A mount, as far as OnStep is concerned, is the part that sits on top of the tripod and has at least two axis with two motors to a) cancel the apparent motion of the sky and b) provide Goto functionality, among other things.

The tripod is just something sturdy that the mounts sits on top of.

If you mean the Sirui SH-15, this is not a mount at all. It has no motors or gears that can be moved by motors.

Howard Dutton
 

The camera is quite decent for astrophotography.

The lens FL is too long for a beginner and would required a good tracking mount to get decent results, assuming optically it's ok for astro imaging, which I seriously doubt.

Converting the tripod into a goto mount would be a dubious exercise, I already linked to the section with mounts typically converted to goto with OnStep, I will say no more.

A kit lens on the DSLR at 50mm or so can take nice wide field shots sitting on the tripod.  Taking those shots, stacking and processing them would be a valuable learning experience applicable to imaging with a telescope later.  Building a barn-door tracker that sits on that tripod should help take things to another level while spending very little.  Perhaps the zoom kit lens at longer FL would be ok then.  You will then learn about basic polar alignment, tracking, and the how and why of exposure times, ISO settings, RAW image format, etc.

If still serious you can start looking at mounts/telescopes at which point OnStep might be useful to you.

debojyoti.pal.007@...
 

Also, I am willing to use Canon 6D Mark ii with Vivitar 650-1300mm with multiple(3) 2x tele-converters giving me 2600mm, 5200mm and 10400mm focal lengths. Am I in the right path? Can I get high end telescope level photographs?