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Meade 2X Telenegative Barlow ?

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#1 tim57064

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Posted 30 June 2013 - 11:22 AM

Hi all,Last night I was out with both my Celestron 8SE and my Meade 2120 10" f/6.3 premiere on an lx200 mount. Anyway the skies seemed to be clear and I suppose my eyes were not dark adapted because of lights near by. I place tarps up as screening to try to block out the light, yet they were not tall enough. The stars were not twinkling yet views were not that great.
Okay, that said,I have a Meade 2x telenegative barlow that I have had since about 1992 and have liked it in the past. It has always had caps on it so it is not dirty and using it last night on Saturn with a meade 13.8 superwide or other eyepieces 20mm qx70 and others, the views were horrendous. everything was much clearer without the barlow. I don't understand why clarity was so bad when it is quite clean,yes a very little bit of dust yet minimal.
Can a lens or barlow lens go bad or be bad even when it looks okay visually? I would appreciate your advice. Thanks, Tim

#2 tim57064

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Posted 30 June 2013 - 11:25 AM

Moderator I just noticed this should probably be placed in the eyepiece forum,would you please move it there if you can ?Please? Or is it okay here?Thanks

#3 star drop

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Posted 30 June 2013 - 11:32 AM

It sounds like the atmosphere above you was not steady enough to support the higher magnifications provided when using the telenegative.

#4 tim57064

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Posted 30 June 2013 - 12:24 PM

The stars were not twinking so I assumed atmosphere was steady.

#5 amicus sidera

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Posted 30 June 2013 - 07:05 PM

Sometimes you can experience what is termed "fast seeing"'; the stars appear to the naked eye to be steady, but in reality a very rapid turbulence will bloat the images of stars and planets, without any pronounced twinkling... nothing will seem to come into sharp focus. Observing underneath the Jet Stream can produce this type of poor seeing.

Fred

#6 tim57064

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Posted 30 June 2013 - 07:35 PM

Thanks for the input.I have been building,viewing thru and upgrading scopes since my first 60mm refractor in '90.I find that now in my near mid 50's remembering all that I have learned is becoming more difficult. It is great that a person is able to come here and be reminded of what has slipped an older mind. Although I know a number of individuals older than I that are sharp as a tack and am still learning from them. I appreciate all responses and advice.
I would also like to know what would be a good barlow to upgrade to for $100.00 or less or if it is worth upgrading with only that much in mind. Thanks, Tim

#7 FoxTrot

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Posted 01 July 2013 - 03:45 AM

Tim, just out of interest what model Meade barlow was it? 140, 126...?

#8 russell23

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Posted 01 July 2013 - 06:17 AM

Hi Tim, You can upgrade to an explore scientific 2x Barlow for $80. It is a 4 element design similar to a Televue Powermate. I am very picky about barlows and am extremely pleased with this one. It provides very sharp views and cleans up edge performance in eyepieces that can't handle my f/5.7 refractor.

Dave






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