collimating a Vernonscope Brandon 94

I am the original owner of a 1990 Brandon 94, the one with the heavy cell, that has the 6 adjustment screws on it (3 large, 3 small, in pairs). I want to make sure it is operating optimally, and was wondering how I should best check the collimation and then what is the recommended sequence to follow.

I own the Orion collimating eyepiece, and no other collimating tools.

Thanks,
-Rich

Rich, you could place the Cheshire into focuser, cap the objective, and flash some light from the side onto Cheshire's 45-degree reflective surface. Curved objective lens surfaces will reflect small amount of this light and form images of the 45-degree surface as circular doughnut shaped images of diferent sizes, intensities and colors, that will float in front of the objective. You may not see more than two or three, and they'll likely be small or hard to see due to relatively small/fast lens. If these reflections are nearly centered and concentric, the alignment is also near perfect. If not, either the lens or the focuser (or both) are not aligned. Small amount of misalignment probably won't do much harm, but if it looks fairly asymmetrical, it is probably good idea to have it fixed.

Here's one procedure that should work. To check out focuser's alignment with the tube, you could suspend a crosshair on the front tube end (w/o objective cell) and see if its center nearly concides with that of Chesire's crosshair. If it does, the misalignment comes from the objective, which should be cemented, so it can't be caused (or shouldn't be) by inter-lens misalignment. What you need to make sure is only that the objective is well centered in the cell. If asymmetry persists, chances are that the cell is not square with the tube. You can confirm that by rotating the cell: direction in which reflections diverge should follow the rotation. Now detrmine which pair of adjustment screws this direction of divergence most closely points to. By loosening or tightening that pair, through trial and error, you should be able to have reflections nearly centered and concentric.