Quote:
Originally Posted by GOTO
Some here have mentioned the quality of the view. Optical quality is one thing but varying staff focus is perhaps a bigger more problematic issue. If anyone can suggest a fast reliable way we can standardise visual focus, again please let me know.
Again thank you for the discussion.
Kind regards
Geoff
geoffw@phm.gov.au |
Hi Geoff
Yes focus is a problem for multiple users. When I am at astronomy nights with my scope. I have two methods.
1. I set the preliminary focus with my glasses on. This sets the start position and works for most viewers but if the viewer has noticeable thickened glasses their focus without glasses will be quite different. When there is sufficient eye relief they can usually view the standard focus with glasses on. But will always require a refocus with glasses off.
2. I have a LX200 that I fitted a mechanical counter to the focus knob. (I am lucky in that my scope has very little image shift with the standard focus knob). This allows re-setting to a standard position when the focus has been adjusted. The precicision of the scale is such that the scale even registers the difference between cold and warm focus by as many a 10 divisions. This method can be fun if you can see what glasses the observers are using. You can soon learn the offset for varying degrees of long sight and short sight by looking at the thickness of the lenses and set focus before they look into the eyepiece.
Barry