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Re: The good and the bad

Started by fct-150, 08/03/2013 01:41AM
Posted 08/03/2013 01:41AM Opening Post
I have had 4 of the B and L 4000 throughout my life. In every instance I find the tine mount is better than the Meade 2045D, but not as pretty. These 4000 mounts are easy for the steady-of-hands to take apart for inspection, re-lubing, and loosening/tightening the necessary bolts. HOWEVER....I have never been a fan of the optical tube. I don't like how it feels "plasticy", the finder scope belongs on a .22 rifle, and the focuser is usually received in "dry" condition; meaning most of the grease has fossilized.

I'm not positive, but I wager by the time the 4000 was into play with the mass-market community, Criterion was simply a label stamped on a somewhat foreign product. When I look upon my ancient Criterion RV-6 and touch the quality of the motor drive and witness the optical impeccability of the mirrors, I find it VERY difficult to associate the name "Criterion" with the 4000.

I did have a pretty good 4000 though. It did the basic M objects very nicely, but it really impressed me on Jupiter and the Moon at half-full. When collimation was precise (or as precise as this tube would allow), resolution and quality of the view bettered the C90. But I did notice dimmer views with it over the Meade's lovely 2045. This could be derived from many things, but I strongly suspect it was the shallow coatings on the corrector of the 4000 that made it lose.

When I was 18, I bought a 4000 at a star party, having always wanted to own one. When I got it home and tested it on Mt. Rainier at 42 miles away, I was happy with the view with the (Y) 30mm plossl. However, once I upped the "juice" with a 25mm or shorter focal length, all went to the soup. I tested it on Venus that night and I was disappointed. I collimated the secondary, but nothing worked. I unscrewed the corrector plate and looked at the mirror and the plate to see if the glass itself was visually uneven. Nothing.
Well, I was so upset with the medium power slop views, that I took a square of tissue paper and a quarter and laid it on the corrector plate itself. When I ran the quarter around the outer perimeter of the plate, the quarter became "jammed" in between the secondary assembly and the metal rim of the tube surrounding the corrector plate! YES!! The secondary itself was offset by several millimeters!
Well, I gave the scope away to a kid in our neighborhood and that was that.

I agree that there are more good 4000s than there are bad ones. But when you find a bad one, it is BAD!

All the best,

Andy S.

Just a few thoughts:

8) FS-152SV sitting in the office
grin Japanes super lucky zen observatory garden
:S Meade ETX-90 finder scope position
shocked Hino Optical Mizar 120SL observatory model
:C SR-4mm eyepiece with a 3x barlow in a 60mm refractor
8O Zeiss Victory 7x42 SFs
wink Having over 135 vintage oculars to play with
smile My life surrounded by wonderful friends and impeccable optics