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Mcrogers1

Mesu 200 Initialization

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Hello,

 

I just got  a little clear weather and thought I would try out the Mesu 200.

If you use plate solving to find targets do you have to sync the Mesu 200 in your planetarium software accurately? I read that you have to sync with a  planetarium program. Can you just sync and be tracking at a sidereal rate? I'll be using ACP and don't plan on using the SKY X other than for the telescope sync function. The mount is moving faster than sidereal and the stars are moving quick on the frame and focus screen of Nebulosity. Not enough to blur but you can see movement at the 1 sec I have the camera set to take pictures.  What I get in Nebulosity is that after every 1 second exposure the stars move and I can't do a fine focus before they move off the small fine focus screen.

I know that I'm doing something wrong. 

Thanks for any help.

 

Mike

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I think that Steve Richards wrote a startup guide available on the Mesu-200 Yahoo group. It has been very widely praised and might help you.

Olly

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Turn your mesu mount on.

Fill in all the setup criteria in the config section (once done it will remember it even when you update.

Connect to a planetarium software.

Slew with the hand pad to a bright obvious star and center in your eyepiece

Sync to the star making sure to do an "offset init"

The mount will now be tracking reasonably accurately.

You can always do an "offset" init near to where you are imaging if you do not want to build a pxp model.

If you still have tracking problems after this let us know.

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Thanks. I will try those things when the weather clears again. I'm not looking for accurate gotos right now. Just trying to get the mount to track at the appropriate speed to do a drift align in PHD 2 and test image with SGP before going through the ACP setup.

I have  Steve Richards' file. I noticed after saving the file with my latitude of 35N it went to 45N the next day. I'll look at that info again today to see if it's correct or changed again.

Thanks for your help.

 

Edited by Mcrogers1

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I use SG pro with my Mesu. After you've gone through the initial setup for the Mesu and got it to the point that it can track once its out of park mode then it can work without the need for planetarium software.

Once everything is powered on and a target sequence opened up in SG pro I slew to the target and then tell SG pro to centre the target. SG pro does a plate solve. When its found where its actually looking, the SciTech screen for setting the initial offset and calibration points (sorry to be so long winded, not at home) pops up.

I  press the init offset button, then SG pro moves the mount to the correct location and does another plate solve. The init offset screen comes up again, I press the init offset button again. If its in the right place then thats it, otherwise the process will repeat until the scope is pointing to within a few pixels of where it should be. It usually does it with two plate solves. It sounds a lot more complicated written down than it is in practice.

Cheers, Ian

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I think my balance is off. I turn on the mount and open up Nebulosity to start taking 1 sec frame and focus images. The stars move up and to the left. After I do the offset init everything seems to be fine. It clouded up again before I could try unpark and start on the Sitech control panel to get the mount tracking at sidreal.

Should the stars move across the Nebulosity screen before doing an offset init or is this an indication of improper balance?

Anyway, w/o even polar aligning the guide graph was better than my CGEM DX.

Sorry for being a newbie

Edited by Mcrogers1

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I don't think that this is balance ......... I've had my stars move across the screen before any sort of initialisation..... I *think* that was sorted by having the settings in Sitech that the mount starts tracking as soon as it's unparked.

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6 hours ago, Mcrogers1 said:

Should the stars move across the Nebulosity screen before doing an offset init or is this an indication of improper balance

Hello,

Before the first init, this is normal. The mount won't start tracking until the first init has been done and is unparked.

Cheers, Ian

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Just now, iansmith said:

Hello,

Before the first init, this is normal. The mount won't start tracking until the first init has been done and is unparked.

Cheers, Ian

I'm not sure this is totally right? I say that as I unpark my mount (so it automatically begins to track) - I can slew to anywhere and without any form of init being done the stars dont move...... I'm probably wrong though :) I usually am when anything technical is involved

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Just now, swag72 said:

I'm not sure this is totally right? I say that as I unpark my mount (so it automatically begins to track) - I can slew to anywhere and without any form of init being done the stars dont move...... I'm probably wrong though :) I usually am when anything technical is involved

Sorry, I wasn't very clear. I think once you've done your first init then the scope will track after it has been unparked. So if you've not done any init or the mount has slipped, then after you unpark it will not track and the stars will move. Once an init has been done, it will track and thereafter it will track after you unparked it. The scope remembers the init offset after it has been turned off and reapplies this when it is switched on.

Hope this clears up any confusion, I haven't had to so this since September so my memory is a bit hazy. Now I just turn it on, slew and centre to my target in SG pro and press the offset init button as required.

Cheers, Ian

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Thanks all. It clouded up before I can test further. I'm used to the CGEM and setting the mount to the index marks before aligning. 

The stars are moving quite a bit.  A few pixels between each 1 sec image update.

So you have to be close to whatever star you are doing sync on for your initial offset init. This way the telescope can compare the RA/Dec position of its encoders to the planetarium's RA/Dec of the sync star. Then you can park/unpark the scope and be tracking as long as the mount hasn't been moved since the park. I hope this is right.

On the CGEM I would go to the index marks and lock the clutches. Click the quick align on the hand pad without actually aligning to anything in the sky. Then so the platesolve in SGP and this worked. I guess with the Mesu not having index marks I need to sync (align) to a star initially so the mount knows where its at.

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21 hours ago, Mcrogers1 said:

I guess with the Mesu not having index marks I need to sync (align) to a star initially so the mount knows where its at.

You do, it can be done via SG pro. Good luck.

Cheers, Ian

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On 17/12/2016 at 12:29, iansmith said:

Sorry, I wasn't very clear. I think once you've done your first init then the scope will track after it has been unparked. So if you've not done any init or the mount has slipped, then after you unpark it will not track and the stars will move. Once an init has been done, it will track and thereafter it will track after you unparked it. The scope remembers the init offset after it has been turned off and reapplies this when it is switched on.

Hope this clears up any confusion, I haven't had to so this since September so my memory is a bit hazy. Now I just turn it on, slew and centre to my target in SG pro and press the offset init button as required.

Cheers, Ian

In the SiTech Config you can select whether the mount starts to track after unparking or after an initial Init.

It sounds like yours is set to track after the first Offset Init and Sara's (and mine!) is set to track as soon as the mount is UnParked.

 

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Never once in all the various payloads we've dumped on our Mesu has balance been worthy of attention. We do it by 'feel,' which can't be very accurate, but not once have we ever felt the need to adjust it thereafter. Either we have been very lucky, or we are very good at 'feel' (most unlikely!!) or it isn't a big deal. On the other hand the SiTech system, which I don't have, does seem to be full of things you could get wrong...

Olly

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Thanks again everyone. I got it working with SGP. I didn't know that it would do an automatic offset init after a plate solve. It went to numerous targets I used for testing.

Now I have to fine tune the PA when the weather clears.

Edited by Mcrogers1

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5 hours ago, Mcrogers1 said:

Thanks again everyone. I got it working with SGP. I didn't know that it would do an automatic offset init after a plate solve. It went to numerous targets I used for testing.

Now I have to fine tune the PA when the weather clears.

Its worth changing the timeout settings in SiTech Config to something like 3 seconds. Then it accepts the result of the synch much more quickly.

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5 hours ago, Mcrogers1 said:

Thanks again everyone. I got it working with SGP. I didn't know that it would do an automatic offset init after a plate solve. It went to numerous targets I used for testing

It's pretty cool isn't it? I haven't used the planetarium software on my observatory PC in months!

Cheers, Ian

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14 hours ago, ollypenrice said:

Never once in all the various payloads we've dumped on our Mesu has balance been worthy of attention. We do it by 'feel,' which can't be very accurate, but not once have we ever felt the need to adjust it thereafter. Either we have been very lucky, or we are very good at 'feel' (most unlikely!!) or it isn't a big deal. On the other hand the SiTech system, which I don't have, does seem to be full of things you could get wrong...

Olly

The Sitech system is 'potentially' complicated, but after you have set it up the first time you can pretty much forget about it.  Follow Mr Richards' guide and it is very difficult to get it wrong.  The only other thing that might get you into difficulty is working out what the optimum settings are for your Meridian flips.  Once again, however, once you have this set you can forget about it.  You will then have a system that can: automatically slew to your target; plate solve and centre on the target; and perform automatic meridian flips, re-centering on your target after the flip.  If I can get this working, then anyone can.            

Edited by gnomus
I used 'one' when I meany 'you' - I must be getting pretentious in my old age...
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14 hours ago, ollypenrice said:

Never once in all the various payloads we've dumped on our Mesu has balance been worthy of attention. We do it by 'feel,' which can't be very accurate, but not once have we ever felt the need to adjust it thereafter. Either we have been very lucky, or we are very good at 'feel' (most unlikely!!) or it isn't a big deal. On the other hand the SiTech system, which I don't have, does seem to be full of things you could get wrong...

Olly

Like you I haven't got my mount exactly balanced (as far as I know!) and it seems to work very well.

Regarding the SciTech, it appears to have a reputation for being very complicated to use, but Mesu set it all up for you, so as an end user of the mount I haven't found it to be any more difficult  to use than any other computerised mount. It could do with some clearer documentation though.

Cheers, Ian

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