Baader sky surfer v finder

[Chubster]

How do I work out the FOV of this ??

[geppetto]

I'm sure theres a technical way but if I want to find a FOV, I look through it

and find two known stars that more or less fit one at each edge then check

the angle between those stars in Starry Night.

[Greg]

How do I work out the FOV of this ??

Can I get all physics on you!!

This works for calculating the true field of view for eyepieces as well.

Find a nice bright star near the celestial equator..One of those ones on Orion's belt is normally a good one!

Turn off your drive and put the star in the most eastern edge of the eyepiece and time how long it takes to get to the other edge of the eyepiece. Do this a couple of times and average the result.

Take the time in minutes and divide by 4 to get the answer in degrees

So for example if the star takes 10 Min's to cross the field of view of the skysurfer divide that by 4 and you get err.....

2.5 degrees!..

[Macavity]

Quick and fairly accurate way (in the absence of stars): Find an eyepiece with known accurate AFOV (I have a certain confidence specific Vixen Lanthanums are 50 Deg) and ergo TFOV. View a nearby house through your scope and count the number of bricks, roof tiles etc. that fill the field. Work out the approx. size of these objects in degrees and tenths. Then it's down to a comparison and a little arithmetic...

[proflight2000]

Thats an interesting idea Phatt, I think I will try that one.