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Baader/Celstron Binos--Achieving focus

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#1 De Lorme

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Posted 19 October 2019 - 04:39 PM

Hello,

 

Was looking at the moon last night and the view was really sharp all the down to 8mm with my Meade zooms without using a barlow or ocs to reach focus in my ES 5" 7.5 .  But when using my Televue 3x barlow to achieve higher power I had to use 2 1.25" extenders plus rack the draw tube almost all the way out. 

 

Other than{the obvious} using pairs of eyepiece to get to much higher powers does anybody have any suggestions to what I can do? Since I was able to come to focus with the zooms I was surprised by this. Just want to make sure I'm not missing something

 

Thanks for the advice,

 

De Lorme



#2 junomike

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Posted 19 October 2019 - 04:44 PM

Get a 4X PM and place it BEFORE the Diagonal.



#3 De Lorme

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Posted 19 October 2019 - 05:04 PM

Hi Junomike,

 

Since these binos have a 60 degree angle it would be impossible to use  my 2" BBHS.  



#4 junomike

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Posted 19 October 2019 - 06:07 PM

Hi Junomike,

 

Since these binos have a 60 degree angle it would be impossible to use  my 2" BBHS.  

Ah ok, then place a 2X Barlow Before the BV.  This will yield around 3X magnification however you still might not be able to reach

focus without an extension. But you could use a 2" ext going into the Barlow (BV's > Barlow > Ext > Focuser).

A Powermate would most reach focus without using an ext.



#5 De Lorme

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Posted 19 October 2019 - 10:44 PM

I did use both of my 1.25 extensions inserted the 3x barlow and last the Baader/Celestron bino. It came to focus but it was putting a lot of strain on the focuser.  

 

When I put the B/C bino into the back without any extensions then put the 3x into the B/C and then the zoom it came to focus but it was quite high. It would also be quite heavy{about 57oz} with 2 zooms and 2 TV 3x  barlows.  I had about 13mm of in-focus left. 

 

I'm now wondering for high power only if the Meade 3x shorty barlows in the same configuration as above would give enough light distance in order to come to focus. I going to see if I can find a used one to test with.

 

Thanks for your help, Junomike.

 

Clear Skies,  De Lorme



#6 junomike

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Posted 20 October 2019 - 03:29 PM

Keep us posted as to what eventually works.



#7 De Lorme

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Posted 29 October 2019 - 04:27 AM

Hello,

 

Well I found the solution to my coming to focus problem. I inserted the TV 3x barlow into the B/C binos and then the Meade zooms into the barlows.

The focuser is 45mm in length.  With the TV 3x barlow and the Meade zoom set on 24x I had to back it out to about 31mm and about 10 to 12mm

with it at 8x.  When using the zooms by themselves to come to focus I turned the focuser back to between 10/11mm with the zooms set at 24x.

I also did this at 8x but I can't remember where the focuser was at. Just know that I came to focus.

 

In comparing the view of the Meade zoom by itself set at 8x with the TV 3x barlow and the Meade zoom at 24x the views seemed about the same.

Will definitely do this again  to make sure what I saw Is what I saw{LOL}. But anyway I'm glad the problem is solved.

 

M39 looked just awesome! Stars were so bright and sharp!  But the field of view was a little restrictive. In thinking that the 1.25" nosepiece was restricting the view I ordered a 2" Baader T2 nosepiece that will be here in a few days. 

I plan to take pictures in every configuration to confirm what I'm seeing.

 

Question: since the TV barlow is behind the bino I'm assuming that it's not lengthening the light path so is the TV is actually working at 3x or close to it, am I right? 

 

Thanks for the help and Clear Skies,  De Lorme




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