Ahhh this goto is driving me crazy!!!!!

[steelfixer]

Morning all.

After yet another wasted night trying to get this goto to work correctly I am at my wits end.

I have an EQ5 mount with the Syncscan upgrade goto fitted.

I am running it direct through EQMOD (no handset)

I have been having problems getting the Sync to work with Stellarium and Cartes so yesterday I started from the very begining again.

I set the mount up using a spirit level to set the 'Home' position as prescribed in the Eqmod tutorial.

I went through all the Ascom driver and telescope set ups.

I found one setting incorrect so changed that and it worked. I had the sync from the planetarium working correctly -- billiant !!! I was ready just had to wait for darkness to fall.

Last night was perfect, crystal clear skies and a perfectly working goto system.

HA HA HA HA How wrong I was.

Sure enough the goto did exactly what it was suposed to.

I selected a star on Cartes selected slew and off the scope went.

It stopped slewing about 10 degrees east short of the star.

No problems I thought, undo the clutches move the scope by hand to center the star in the EP and then press sync.

Brilliant - first point set now off to the next star.

Select another star - press slew off the scope goes.

Stops about 10 degrees east short again.

Center star using the motors and sync.

Second star set.

Send the scope off to Vega for the third star point.

Scope stops well short of Vega because I am now getting a Meridan limit stop on the computer.

Well I am now totally confused - Vega is no where near the Meridian.

Ok scrap the idea of using Cartes and use the Tour function on Eqmod after resetting the home position.

Select first star from the tour list of stars and off the scope goes.

Slew stops and the star is again about 10 degrees east short.

So manually adjust and sync.

Send the scope off to Vega scope stops well short of target but at least no Meridian limit warnings.

Center Vega in the EP using the motors and sync.

Slect third star, again scope stops short of target and yet again it stops short about 10 degrees east.

Center target using motors and sync.

Send the scope back to Vega to check all is now correct.

The scope is so far out I cannot even see Vega through the finder scope.

Count to 10 and start over again.

Exactly the same result select stars adjust sync. Return to star and nowhere near.

Count to 100 switch off the entire set up close to roof on the obs and got to bed very unhappy - yet again.

If anyone has the remotest idea what I am doing wrong let me know because I am now totally out of ideas.

Thank you.

Graham

[pjmaciw]

I am learning how to set up the goto myself, so I'm no expert. I do a similar setup as you but do not release the clutches to align. I use the software to align and then sync. The sync then moves the scope icon to the selectwd object.

Pete.

[Sparrow]

No problems I thought, undo the clutches move the scope by hand to

This is where your problem is. When you're doing your star alignment, you need to correct this first star and subsequent stars for alignment using the motors - if you release the clutches and move it, the scope has no idea of the correction being made and subsequent alignment stars will have the same error.

Regards

John

[bcfcciderhead]

I had a problem like that until last night where everything worked great,

Not sure how the EQMOD works but if you are using the GOTO handset change the time scale to plus one hour, after you set your location, date time the next screen looks like this +00:00 change it to +01:00 the next screen is daylight saving? select yes,

Before i done this i was always out like you even the moon was outside the EP!

I also DO NOT release the clutches to adjust, use the direction buttons on the handset.

Just a thought and best of luck, someone will put you right

[adamsp123]

If the error is in RA only then my bet would be on a time zone/daylight saving error as Dave suggested above.

[steelfixer]

Hi folks.

Thanks for the replies.

I figured that on the first star it would be ok to adjust the scope by releasing the clutches as the goto would think it was in the correct place.

I will try your advised method to align the first star with the motor drives.

Oh the wonders of modern tech.lol

thanks again

Graham

[steelfixer]

Hi Pete.

The problem seems to be in RA only but the Eqmod uses the computers clock to sync the time so it should ( and I use the term loosley ) be correct.

[bcfcciderhead]

Hi Pete.

The problem seems to be in RA only but the Eqmod uses the computers clock to sync the time so it should ( and I use the term loosley ) be correct.

But does the Eqmod & computers clock know its BST? the time might be correct (i use my computers time to set up) but it wont know about daylight saving times........i think

[steelfixer]

That is a good point Dave.

I will have to investigate that.

[steelfixer]

I think I might just plug in the Synscan handset and try it on that. If it cures the problems then I know hopefully that the problem lies in the time input on the Eqmod.

Mind changing the time clock on Eqmod might just gain me more problems as I have no idea how to adjust it.

[rjsc2001]

The manual movement of the mount to point to the first star when it's off has to do with polar align, i think.

For the goto to be precise you must be polar aligned. You see, the controller starts from the home position (pointing to north celestial pole) and moves to a point in the sky where the star is. The more accurate your polar align the lesser your error when pointing to the first star.

But when you put the scope in the home position, you can't put it in the 'exact' position. There are always errors. The backslash of the gears, for example. You must do a 2 or 3 star align so that the mount makes a 'model' of the sky, so that when goto, it compensates for the errors. When you do this 2 or 3 star align, it doesn't matter if you are polar align or not because the mount calculates how far you are from the north celestial pole.

When doing this align, use a reticle eyepiece or a high power, so that you can center the object with more precision. Failing to do this, makes the align inaccurate.

Set the backslash of the gears correctly.

My GOTONOVA shows the error relative to the north celestial pole after the 2/3 star align. After this align i move the azimuth or altitude a little and align again. I then noticed that the error to the first star is smaller. And i do first the azimuth and then the altitude, so that i don't mix things. This constant slews drains the battery of my powertank considerably.

What you can try is, put in the home position, align to the 1st star and move the mount in azimuth for half the distance to the star. Then abort the align. Go back to the home position and then start the 2/3 star align. The error should be smaller. Then try the altitude.

There's the yahoo group for the EQ6 and EQMOD. And in youtube

which i think relates to your system but i'm not sure.

Ricardo

[steelfixer]

Hi Ricardo.

Thanks for the input.

My scope is pier mounted in an obs.

It is perfectly polar alligned hence my total frustration with the goto.

I align with a 20mm ep then a 6mm ep then move on to my SPC900 with a 3x barlow so the final alignment should be pretty close.

thanks

graham

[rjsc2001]

Check the backslash settings. Does the HC (hand controller) has a routine to do it? Point to a terrestrial object though.

When centering don't go one direction and then the other. Always try to use one direction only.

Check to see if the spur gears are tighten. When they start to rotate, check to see if the shaft turns at the same time as the spur gears. The grub screw that holds the spur gear maybe loose.

Check if the battery is fully charged.

See if the position given by the HC is the same as the one in cartes.

Double check your Lat/long and daylight saving and local time.

After that... i don't know.

[steelfixer]

Hi Ricardo

I have been all through the gear train and all is ok.

I run off mains power in the obs so that takes care of power issues.

I am going to try running the mount off the handset tonight to see if it is any better.

If it cures this problem then I will know it is a time issue I have with the Eqmod.

I am even going to plug in a GPS mouse to sort out the long and lat.

You say "after that I don't know" welcome to my world. lol

Thanks for your help.

Graham

[rjsc2001]

Any time.

I've described some of my problems. The ones that made the most effect were:

Centering with a reticle eyepiece.

Good starting home position.

Polar Align

Ricardo

[adamsp123]

Simple way to check if it is a daylight saving error is to see if you have to move the mount 15 degrees in RA to centre the star, if yes then that is the cause, the "system" time is an hour out.

[bcfcciderhead]

I'm a 100% sure it's a time thing,

i say this because it's doing the same thing i had last week, input you long/lat - input date (american format) - input time - input +01:00 (this is what fixed mine, i was leaving it +00:00) - input daylight saveing to yes.

It worked for me and before i done this i was always about 15 degrees of target, sometimes more

[steelfixer]

Hi Pete.

15 degrees you say.

Well sir you are a genius because that is just about what I am short of in RA movement when slewing to targets.

Now if someone knows how to get the clock readjusted in Eqmod and my problems will be over. lol

thanks again

Graham

[steelfixer]

Hi again Dave.

By running Eqmod you do away with the sycnscan handset altogether and just use the computer.

The only problem I have is as far as I know there is no daylight saving setting in the Eqmod set up as it syncs with the computers clock.

I need to somehow alter the clock in Eqmod but I donot know how.

I suppose if it comes to it I could alter the computers clock to compensate for the lost hour.

Like I have said before I will try the handset on it tonight and hopefully it will cure this annoying problem.

thanks

Graham

[Psychobilly]

15 degrees is an approximation because 1 sidereal day = 23.9344696 hours not 24.... but it's as near an damn it is to swearing for this exercise...

[ronin]

Vega is close to the meridian.

From around 22:00 it is pretty much over head as is Deneb.

Which makes me think the system knew where it was and so was operating correctly.

[jana]

with regard to changing the time zone to 01.00 from 00.00 should this be done? i was under the impression that it should always be at 00.00 and daylight saving to yes in BST.

I was having trouble last night with my two star alignment failing but on the third or forth go I found two bright stars one to the west and one north east. had to move the scope with direction buttons to centre both but then all worked fine for the night.

Was I just luck it worked or did I do it properly and the changing time zone is just to fool the system as so to speak?

[rjsc2001]

The time zone dependes on where you are relating to GMT.

The time is your local time.

If you are on DST then put it to YES.

That is how my GOTONOVA works. This way, it's the HC that makes the math and not us.

But i'm not sure of it in your model.

Ricardo

[chrisshillito]

Graham,

If your PC clock is set correctly (i.e. the widows clock is showing correct local time) then EQMOD will also be using the correct time (it uses windows UTC so daylight savings are irrelevant). There really should be no need to attempt to force any adjustments.

If you have started form a reasonably accurate home position, with reasonable polar alignment and a level mount the the intital goto should be close to target. Certainly within your fiderscope. If it isn't then check your site settings. It is possible with EQMOD to accidentally enter more digits in to the latitude/longitude fields that are displayed - for instance you could accidetally enter 100 minutes but the display would only show 10 - perhaps something to check.

Also before starting a new alignment make sure any existing syncs or points are cleared - there are buttons to do this.

There was nothing wrong with your procedure of manually centering the first alignment point (but only the first point) and this is usually a good way of refining your home position. Check this by parking to home (after syncing on that first point) - the mount should assume the standard home position with the counter weights straight down. If it doesn't then there is little point in doing any further alignment as something is already fundamentally wrong.

Chris.