View Single Post
Old 21-03-2018, 10:29 AM

JA is offline
Join Date: Oct 2016
Location: Melbourne, Australia
Posts: 1,642
Hi Glen,

This is one I have used....

1. Input Focal Length
2. Select Sensor Size Option that suits or input exact size if not listed- 1 to 9 with button on left . (Usually 1,2,3 or 4 used)
3. CLICK Compute 1-9
4. Observe FOV results in decimal Degrees on Right Hand Side Top. There are also some field width results possible if one inputs subject distance (I don't use it. Move relevant to terrestrial and could do the same knowing the FOV with some trig)

Regarding your requirement for a 4 x 3 degree FOV, and as per the attached notated ScantipsFOV excerpt (for your case), you could also use a Full Frame camera with (36mm x 24mm SensorAspect) with your existing 442mm Focal Length refractor/reducer and that would give you a 4.7 x 3.1 degree FOV

Or at the sort of focal length you're interested in use a 300mm lens

Attached Thumbnails
Click for full-size image (FOV 442mm Focal Length Calc.jpg)
118.1 KB15 views

Last edited by JA; 21-03-2018 at 11:21 AM. Reason: added ScantipsFOV Excerpt
Reply With Quote