well that was interesting...

CalStar is clouded out this year.  And with the change in my job I finally had time to drive up to Oakland to the Telescope Makers workshop.  I took my two Jaegers objectives up.

They had no means to test it but they did confirm the crown and flint were mounted in the correct positions.  My only means to verify their focal lengths and check for quality was to mount them back in the scope and look at a star; which is what I did tonight.

Seeing was poor and transparency was worse, but I mounted the first one (with the red ring around the outside of the cell) into the scope.  I tried Sirius first but it looked wild, with a bright halo around it and a spikey middle.  Thinking it was too bright I moved the scope up to Procyon, and unfortunately the view was similar.  A large bright halo around the focused star, looking very much like a solar corona.  Outside of focus had a round purple and yellow ring with a spikey cross in the middle like diffraction rings.  It was not oval shape, so I don't think it's astigmatism, but it's not a good sign.  Fainter stars focused pretty well but the halo must mean the glass is mounted incorrectly, and is maybe pinched in its cell.  I recorded the focus distance with the 22mm Nagler and 13mm Ethos, will check it later.

I slipped it out and put the other objective in.  This time I could not reach focus with the 22mm Nagler even with the extension tube -- meaning I need to get another extension tube to check it.  But, while pulling the eyepiece slowly out of the focuser drawtube the stars did come to focus at a certain point, and the view was clean.  So I think the glass is ok.

Now I need to play around with red's mounting to see what's wrong.  The crown and flint might be in the correct order but one of them must be reversed.  If I can get it to work then I can proceed; otherwise maybe sell it.  I'm having trouble removing the glass from the cell, so it might be difficult to recover this one.

BTW I used mineral oil as a lubricant between the cells and the objective holder on the telescope -- the lubrication worked well and I had no trouble getting the cells in and out.  But the oil does not wipe off, so I need to be extra careful not to touch any glass.