How to make a first pointing file?

[MichiP]

Hello,

 

a few weeks ago, I decided to update Autoslew from version 5.0.3 to actual 5.1.x

I made a complete new pointing file with Autoslew and The Sky by doing this steps:

 

• start/add Pointingfile
• move telescope to a known star in The sky
• centering the star in the ocular and press sync in The Sky
• GoTo different stars, each centered and after each star pressing the check in Autoslew, no sync in The Sky.
• Stop pointing file
• calculate and save

 

When I slew to a new object, the will not be centered in the middle. Before I did the update, I had a perfect pointing and the objects are always nearly perfect centered. I'm using a Celestron C14 which had no mirror lock when I was using the old version of AutoSlew. Installed a mirror lock now and changed some components so eliminate possible tube flex. So now the pointing should over the complete horizon nearly perfect. I should mention that I made the pointing file only on the east sky, but in the past it worked very well. Longest unguided full length exposure was 45 minutes

 

Does anybody see what I'm doing wrong?

 

 

There are some upcoming questions.

 

• When I click on "Start/add Pointingfile" I always get this info box by Autoslew.

I get this message also when I have synced a star in The Sky and it makes no difference if I click on "set new Home position" in Autoslew.

 

 

• Do you sync a star before starting the pointing file?
• Do you move from east to the west sky and proced there the pointing file?

 

I know I should use Sequenz and MLPT but before I start with this, I need solve some trouble with Maxim DL, so just on step after after the other

 

 

Best regards,

Michael

[GeorgeCarey]

I assume you have got a good polar alignment?

 

Before you make the new pointing file you could try deleting the old configuration.

Then align on a star and sync.

Then start the new pointing file. Ignore the message that comes up and says you need to sync - you already have.

Do 5 stars in the West and 5 stars in the East.

Calculate and save.

 

George

[RamaSpaceShip]

Hi Michael,

 

I fully agree with Gearge's comment.

 

In addition, you can first click the "Clear Old Configuration" button in the "Pointing" menu.

 

I only use the east side as I don't need to do meridian flips. So my pointing file only contains stars on the east. This does not cause any problem.

 

I had a similar issue than yours (may-be the same) when I started to make pointing files. When I clicked "Calculate Configuration", I got strange huge pointing error values. Investigating further, I noticed that Autoslew displays the pointing error of each star after you validate its position to add it in the pointing file (look at the bottom of the Autoslew window). If your polar alignment is good (and I am sure it  is), the values displayed must be small. Sometimes, the values displayed are big (more than 100 and in my case always more than 1000), this means that there is something wrong with that star (Mr Keller, can you please explain us what is going on in that case?). You must discard this star immediately from the pointing file using the "Delete Last Star" button to avoid the corruption of your pointing file.

 

So when you do your pointing file, verify each time you add a star that the error values displayed  at the bottom of the window are small. May be the software should reject such an addition to avoid the pointing file corruption (Mr Keller, can you please add this check and propose to remove the star if the values are too big?).

 

 

Regards.

 

Bernard

Edited November 1, 2013 by RamaSpaceShip

[MichiP]

Hello,

 

thank you for your suggestions. I'll perform the next pointingfile in that way. Just have to wait for better weather. Can't wait to start again making long exposure images after serveral years of building the observatory and solving thousands of problems.

 

@Bernhards, thank you for the hint. I never realizied the values in the bottom line.

 

Best regards,

Michael