A Space & astronomy forum. SpaceBanter.com

Go Back   Home » SpaceBanter.com forum » Others » Misc
Site Map Home Authors List Search Today's Posts Mark Forums Read Web Partners

Calculating Field of view in degrees.



 
 
Thread Tools Display Modes
  #1  
Old September 22nd 03, 12:15 AM
Ernest A. Martsching
external usenet poster
 
Posts: n/a
Default Calculating Field of view in degrees.

I'm wondering how difficult it is to calculate the field of view for my
binoculars and finder scope.
The binoculars are a pair of ProOptic 11x70 and an old pair of Jason 10x50
and the finder is an 8x50.
I'd like to plug those values into my planetarium program.
Thanks in advance.


  #2  
Old September 22nd 03, 02:59 AM
Llanzlan Klazmon The 15th
external usenet poster
 
Posts: n/a
Default

"Ernest A. Martsching" wrote in
:

I'm wondering how difficult it is to calculate the field of view for
my binoculars and finder scope.
The binoculars are a pair of ProOptic 11x70 and an old pair of Jason
10x50 and the finder is an 8x50.
I'd like to plug those values into my planetarium program.
Thanks in advance.




You can't calculate the field of view from the information you have
provided. If you knew the AFOV provided by the eyepieces you could
calculate the TFOV = AFOV / M. (M = magnification). Of course you could
measure the TFOV directly. Most binos specs specity AFOV and/or TFOV.

Llanzlan.
  #3  
Old September 22nd 03, 02:59 AM
Llanzlan Klazmon The 15th
external usenet poster
 
Posts: n/a
Default

"Ernest A. Martsching" wrote in
:

I'm wondering how difficult it is to calculate the field of view for
my binoculars and finder scope.
The binoculars are a pair of ProOptic 11x70 and an old pair of Jason
10x50 and the finder is an 8x50.
I'd like to plug those values into my planetarium program.
Thanks in advance.




You can't calculate the field of view from the information you have
provided. If you knew the AFOV provided by the eyepieces you could
calculate the TFOV = AFOV / M. (M = magnification). Of course you could
measure the TFOV directly. Most binos specs specity AFOV and/or TFOV.

Llanzlan.
  #4  
Old September 22nd 03, 02:42 PM
riff
external usenet poster
 
Posts: n/a
Default

"Ernest A. Martsching" wrote in message
...
I'm wondering how difficult it is to calculate the field of view for my
binoculars and finder scope.
The binoculars are a pair of ProOptic 11x70 and an old pair of Jason 10x50
and the finder is an 8x50.
I'd like to plug those values into my planetarium program.
Thanks in advance.


I asked a similar question in sci.astro.amateur recently (more for binos).
On binos the field of view in feet/yards is usually indicated between the
eyepieces and I asked how to convert to degrees for a similar use as yours:

http://tinyurl.com/o7qm

hth,
-riff


  #5  
Old September 22nd 03, 02:42 PM
riff
external usenet poster
 
Posts: n/a
Default

"Ernest A. Martsching" wrote in message
...
I'm wondering how difficult it is to calculate the field of view for my
binoculars and finder scope.
The binoculars are a pair of ProOptic 11x70 and an old pair of Jason 10x50
and the finder is an 8x50.
I'd like to plug those values into my planetarium program.
Thanks in advance.


I asked a similar question in sci.astro.amateur recently (more for binos).
On binos the field of view in feet/yards is usually indicated between the
eyepieces and I asked how to convert to degrees for a similar use as yours:

http://tinyurl.com/o7qm

hth,
-riff


  #6  
Old September 23rd 03, 06:42 AM
David Knisely
external usenet poster
 
Posts: n/a
Default

Ernest A. Martsching wrote:

I'm wondering how difficult it is to calculate the field of view for my
binoculars and finder scope.
The binoculars are a pair of ProOptic 11x70 and an old pair of Jason 10x50
and the finder is an 8x50.
I'd like to plug those values into my planetarium program.
Thanks in advance.


Usually, many binoculars are stamped with the field in the form of the number
of feet wide the view is at a set distance like 1000 yards. For example, my
old 10x50's are 356 feet at 1000 yards (3,000 feet). To a fair approximation,
take half with width of the field and divide it by the range figure (3000 feet
in the case of many American binos), then take the inverse tangent of that
number and multiply it by two. That should give you the field in degrees. My
old Traq 10x50's have a field of about 7 degrees (lousy outer field quality),
and my new Celestron 10x60's have a field of 5.3 degrees (very sharp). Clear
skies to you.
--
David W. Knisely
Prairie Astronomy Club:
http://www.prairieastronomyclub.org
Hyde Memorial Observatory: http://www.hydeobservatory.info/

**********************************************
* Attend the 10th Annual NEBRASKA STAR PARTY *
* July 27-Aug. 1st, 2003, Merritt Reservoir *
* http://www.NebraskaStarParty.org *
**********************************************



  #7  
Old September 23rd 03, 06:42 AM
David Knisely
external usenet poster
 
Posts: n/a
Default

Ernest A. Martsching wrote:

I'm wondering how difficult it is to calculate the field of view for my
binoculars and finder scope.
The binoculars are a pair of ProOptic 11x70 and an old pair of Jason 10x50
and the finder is an 8x50.
I'd like to plug those values into my planetarium program.
Thanks in advance.


Usually, many binoculars are stamped with the field in the form of the number
of feet wide the view is at a set distance like 1000 yards. For example, my
old 10x50's are 356 feet at 1000 yards (3,000 feet). To a fair approximation,
take half with width of the field and divide it by the range figure (3000 feet
in the case of many American binos), then take the inverse tangent of that
number and multiply it by two. That should give you the field in degrees. My
old Traq 10x50's have a field of about 7 degrees (lousy outer field quality),
and my new Celestron 10x60's have a field of 5.3 degrees (very sharp). Clear
skies to you.
--
David W. Knisely
Prairie Astronomy Club:
http://www.prairieastronomyclub.org
Hyde Memorial Observatory: http://www.hydeobservatory.info/

**********************************************
* Attend the 10th Annual NEBRASKA STAR PARTY *
* July 27-Aug. 1st, 2003, Merritt Reservoir *
* http://www.NebraskaStarParty.org *
**********************************************



  #8  
Old September 24th 03, 01:32 AM
Ernest A. Martsching
external usenet poster
 
Posts: n/a
Default

Thank you to all that replied.
Since I'm an English major and not a math, I think I'll go with Llanzlan's
methodology since it will give me the actual field of view.


"Ernest A. Martsching" wrote in message
...
I'm wondering how difficult it is to calculate the field of view for my
binoculars and finder scope.
The binoculars are a pair of ProOptic 11x70 and an old pair of Jason 10x50
and the finder is an 8x50.
I'd like to plug those values into my planetarium program.
Thanks in advance.




  #9  
Old September 24th 03, 01:32 AM
Ernest A. Martsching
external usenet poster
 
Posts: n/a
Default

Thank you to all that replied.
Since I'm an English major and not a math, I think I'll go with Llanzlan's
methodology since it will give me the actual field of view.


"Ernest A. Martsching" wrote in message
...
I'm wondering how difficult it is to calculate the field of view for my
binoculars and finder scope.
The binoculars are a pair of ProOptic 11x70 and an old pair of Jason 10x50
and the finder is an 8x50.
I'd like to plug those values into my planetarium program.
Thanks in advance.




 




Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

vB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Forum Jump

Similar Threads
Thread Thread Starter Forum Replies Last Post
naive question about FOV IRR Amateur Astronomy 11 August 4th 04 05:43 PM
What exactly is the "Diffraction Limited Field of View"? Derek Overdahl Amateur Astronomy 10 July 23rd 04 01:00 PM
Bands of Saturn. How many of them can be counted (really!) with 7" scope? ValeryD Amateur Astronomy 294 January 26th 04 09:18 PM
Binoculars field of view in degrees Jon Isaacs Amateur Astronomy 9 September 13th 03 05:25 AM
Incontrovertible Evidence Cash Amateur Astronomy 6 August 24th 03 07:22 PM


All times are GMT +1. The time now is 02:54 PM.


Powered by vBulletin® Version 3.6.4
Copyright ©2000 - 2024, Jelsoft Enterprises Ltd.
Copyright ©2004-2024 SpaceBanter.com.
The comments are property of their posters.