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ETX 90 like soptting scope?

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#26 redlinedb16a

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Posted 24 July 2013 - 10:39 PM

I deforked my etx90ra(simply unscrewing 4 screws)and put it on a camera tripod,it's mag power is too strong for objects closer than 300' though
A bird at 500' is almost too large for the feild of view

#27 dengwer

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Posted 25 July 2013 - 02:23 PM

a 40mm eyepiece gives about 30X. good down to about 40ft.

#28 Christopher Erickson

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Posted 26 July 2013 - 04:43 PM

a 40mm eyepiece gives about 30X. good down to about 40ft.


In 1.25", 40mm eyepieces don't show you any more true field of view than a 32mm eyepiece.

They just show it to you smaller.

#29 *skyguy*

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Posted 26 July 2013 - 07:30 PM

a 40mm eyepiece gives about 30X. good down to about 40ft.


In 1.25", 40mm eyepieces don't show you any more true field of view than a 32mm eyepiece.

They just show it to you smaller.


Smaller, but brighter! ;)

#30 redlinedb16a

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Posted 27 July 2013 - 07:44 PM

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#31 Ekyprotic

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Posted 19 January 2014 - 03:16 AM

Sorry to revive an old thread but I am about to get the Meade SCT adapter fpor the ETX and they said to get the eyepiece holder too- cant I use the eyepiece holder that I use with my 8SE on the ETX 90?

Another question, is there any vignetting with the ETX 90 and the 6.3 Celestron FR when used with a 32mm Plossl? What is the widest possible true field of view with this combo?

I also saw a Scopetronix f/6.9 (halves the f number doubles the field of view?) being mentioned here- not sure if it is available anymore

http://zengine.ho8.com/hardware.htm

Scopetronix ETX Focal Reducer, F/13.8 to F/6.9...this little beauty doubled the field of view of my ETX90!

http://zengine.ho8.c...Focal--Redu.jpg

another advantage of this would be no need to get the SCT adapter (maybe I could just use the top port?) something I worry with using the rear cell is getting dust inside the OTA- is this an issue?

#32 Ekyprotic

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Posted 19 January 2014 - 03:19 AM

Here he mentions using a 6.3 Celestron FR but says the field of view is almost doubled!

http://www.weasner.c...chtips/sct.html

#33 Ekyprotic

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Posted 19 January 2014 - 03:29 AM

I also have an Orion .5 reducer that screws onto a DSI camera, can this also be used visually?

Also, does the Celestron .63 FR perform field flattening as well as reducing or do MAKs not need field flattening like SCTs do?






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