Long and short barlow difference?

[pat]

Is there a performance difference between a long barlow and a shorty barlow?

I have always liked my long 2x Meade TeleNegitive barlow (Two elements, I believe). In my 10"f4.7 Orion scope. Better then the Celestron Ultima sv series shorty and the Meade Telenegitive shorty. Useing various eyepieces my Meade seems to perform better. I have not had the chance to try the 2x TeleVue long Barlow. Pat

Too many stars too little time

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[LukeSkywatcher]

I was just wondering the same.

I just sold a Tal 2x barlow and am thinking of buying an Antares 2x to replace it.

i'm wondering what the difference is between a long and short barlow.

[pat]

I talked with Mr. Naglar of TeleVue, and he agrees that a longer barlow is better than a short one. Since we were on another topic, I didn't go into the details why. Pat

[jkwhinfrey]

Could it be that the longer optical path length makes them less sensitive to optical aberration / focus, a bit like slow and fast achromatic scopes?

I'm definitely no optics expert - as this question may indicate - but old scopes used to maintain greater separation between elements so that high performance could be obtained without high tech materials.

... Or I could just be wrong

[pat]

Hi,

I posted this question on "Astronomy forum". And got a good explanation, optically speaking, that is. Pat