Telescope Vanes

Discussion in 'Astronomy, Exobiology, & Cosmology' started by Xmo1, Jul 21, 2018.

  1. Xelasnave.1947 Valued Senior Member

    Messages:
    5,039
    This is not entirely correct and to achieve focus is an exhausting proceedure.

    In the program Startools there is a function "Sync" which enables one to enter details about the vanes, thickness etc, so the program can minimise the effect of the vanes on an image.
    I dont use that feature at the moment as I actually like diffraction spikes in my images...some dont.

    Alex
     
    Write4U likes this.
  2. Google AdSense Guest Advertisement



    to hide all adverts.
  3. Xelasnave.1947 Valued Senior Member

    Messages:
    5,039
    As to focus...

    When you get to the pointy end of the game one usually replaces the standard focuser that comes with any scope with an after market unit that have a greater carrying capacity and have a temperature sensor that is read by an appropriate program which automatically adjust focus as temperature varies during the course of an imaging session.
    The cost of a good focuser can cost up to $4000.
    I use a free program called Sharpcap for mount control, camera control, filter wheel control and to turn on and control the camera cooler unit.
    And in that program there is a feature to assist getting focus near perfect.
    In the old days I may take 50 photos in the course of getting focus perfect where as now it takes only about 5 to 10 minutes.
    I use a focuser mask that shows three lines intersecting which the program looks at and tells you that they are balanced which is better than eyeballing the "cross".

    I adjust focus manually between each run of say 20 images of 2 minutes each as I dont feel inclinded to spend $4000 to automate that aspect of the proceedure.

    I can get away with manual focus because I use relatively short focal lengths although my 8 inch Newtonian reflector has a focal length of 1000 mm which would benefit from a temperature controlled focuser.

    As I tune the set up I will probably have to go for such a focuser as the motor can move the focuser thru much smaller steps than one can do manually.

    I do have electric focusers but rather cheap at $100 for each scope but these are not yet controlled via software...but maybe they will save me getting the one with a temp control.



    Alex
     
    Last edited: Sep 8, 2018
    Write4U likes this.
  4. Google AdSense Guest Advertisement



    to hide all adverts.

Share This Page