Looking for zoom eyepiece

[astrobargains]

Hi Astrobargain,
I went to the website http://www.astrobargains.com/#EYEPIECES and found the description, but the link is wrong. Anyway, I went to Televue webpage and see that there is 2 types of zoom eyepiece: Nagler Zoom and Click Stop Zoom.

Oops...thanks for helping me find an incorrect link. Will fix it.

I hope you have patience for un-experienced buyer...

Astronomy as a hobby makes one almost infinitely patient. It takes a long time for "events" to happen, like clear skies, oppositions, the earth to rotate and/or revolve, etc... :-P

1. What is the difference between TeleVue Nagler Zoom and Click Stop Zoom?

Main difference is just the focal length. So the thing to look at is which focal ranges you want : 2-4mm, 3-5mm, or 8-24mm. They give very different magnifications when you use them. Nagler is used to indicate a certain type of eyepiece design - by Al Nagler. The 8-24mm is probably a more generic design (i.e. could buy from other manufacturers too - but of course will not be the same quality).

2. What is "click stop". It is mentioned in both TeleVue Nagler & Click Stop Zoom.

The "Click Stop" is a marketing term. Both Nagler Zoom and Click Stop zooms will "click" at particular zoom settings. The MAIN purpose for the "Click Stop" is for binocular viewing - i.e. when you have TWO of these eyepieces and using them TOGETHER. Used in this mode, you have to have both eyepieces at EXACTLY the same focal length, so the "clicks" helps you set this..

If you're not familiar with binocular viewing, can research it on the internet or come see it in action at star parties or in shops.

3. TeleVue Nagler zoom looks like a telescopic zoom (meaning the thing extend and retract for different "click stop". True or not?

Yes, the Nagler Zooms do extend and retract.

4. Click TeleVue Stop Zoom does not. True or not?

The Click Stop Zoom does not extend and retract (the moving parts are within the eyepiece barrel).

5. They do not seem to have that continuous zoom like in camera. Is there such thing?

They are BOTH continuous zoom like in camera lenses. You can zoom continuously through the ranges specified. It's just that you can feel the click stops when you hit certain focal lengths. It would actually be pretty cool if camera zoom lenses had this too wouldn't it.

Hope this helps !

Best regards,

[Aryanto]

Thank you Canopus Lim, WeiXing, astrobargains! :goodjob:

Will there be an outings for me to borrow and take a look at these?
It is quite expensive, so I rather try before buy. :k-?:

[chrisyeo]

Seems like Arief is selling a zoom eyepiece..