Messier 13

[bottletopburly]

M13 , 3.9 hrs 120 sec exposure zwo533mc, stacked in Astap processing in Startools 8, there is a reflection on the bright star not too sure where from anyone know of a possible cause let me know.

Dave 

[bottletopburly]

@alacant steve any idea what may be causing the reflection on the bright star ? 

[alacant]

3 hours ago, bottletopburly said:

any idea

Hi

Guessing sw pds...

• Is it on all the individual frames?
• Are the mirror clips still in place?
• Are the tube, focuser internals, secondary mirror edges  and spider blackened?
• Visually looking down the tube with a torch, anything reflective/dirty?

As it's to one edge, my first guess is focuser intrusion.

[bottletopburly]

1 hour ago, alacant said:

Hi

Guessing sw pds...

• Is it on all the individual frames?
• Are the mirror clips still in place?
• Are the tube, focuser internals, secondary mirror edges  and spider blackened?
• Visually looking down the tube with a torch, anything reflective/dirty?

As it's to one edge, my first guess is focuser intrusion.

200pds , flocked tube  ,apeture mask snug fit and  returns slightly down side and covers clips so confident that’s not issue but will shower cap ota end to make sure , baader steeltack fitted I think there is a possibility of light leak where drawtube goes through verabase , I will double check there’s no shiny nuts in ota , I don’t think there is and secondary edge blackened  , spider not blackened by me only stock black , will check individual frames .

[alacant]

20 minutes ago, bottletopburly said:

apeture mask

Any irregularity? Best remove both it and the mirror clips. 

[bottletopburly]

1 hour ago, alacant said:

Any irregularity? Best remove both it and the mirror clips. 

The aperture mask is 3D printed and covers the clips I will look into it and see if there’s anything obvious cheers steve .

[bottletopburly]

@alacant just checked four possible culprits, focuser light leak , two screws thread where black  paint has come off , spider vane holder screws, light from primary don’t think this is the issue but will cover , focuser and screws are the primary candidates.

 

dave