Astro. Is there a way of calculating Field of view for given focal lengths ?

[BADGER.BRAD]

Is there a way of calculating Field of view for given focal lengths ? I'm very new to Astro ( first couple of tries yesterday) but wondered what field of view to expect from my various lenses !

Thanks all

 

[john.margetts]

If you have Canon lenses, they tell you on the leaflet that comes with the lens. Canon also provide this information on line in the details for each lens, giving the horizontal, vertical and diagonal angle of view. Hopefully, other makers do the same.

 

[BADGER.BRAD]

I'll see what I can find but most of my lenses are from the 1970's and 80's

 

[g4aaw]

Hello Brad

There's usually an archive site somewhere with the manufacturer's documentation on F.O.V.

 

[john.margetts]

When in doubt, refer to the Ilford Manual of Photography. They provide this table for you delectation. Divide the diagonal of your sensor by the focal length of your lens and use that to look up the angle in this table.

 

[LeeRatters]

You don't need leaflets from the 1970's

Just search it - This is obviously 35mm/FF format.

Focal length (mm)	Diagonal (°)	Vertical (°)	Horizontal (°)
0	180.0	180.0	180.0
2	169.4	161.1	166.9
12	122.0	90.0	111.1
14	114.2	81.2	102.7
16	107.1	73.9	95.1
20	94.5	61.9	82.4
24	84.1	53.1	73.7
35	63.4	37.8	54.4
50	46.8	27.0	39.6
70	34.4	19.5	28.8
85	28.6	16.1	23.9
105	23.3	13.0	19.5
200	12.3	6.87	10.3
300	8.25	4.58	6.87
400	6.19	3.44	5.15
500	4.96	2.75	4.12
600	4.13	2.29	3.44
700	3.54	1.96	2.95
800	3.10	1.72	2.58
1200	2.07	1.15	1.72

 

[BADGER.BRAD]

Thanks for your help, my camera has an APS-C sensor but I found this

Focal length (35mm)	Equivalent focal length	Field of View
11mm	17.6	91.3
14mm	22.4	77.6
16mm	25.6	70.2
24mm	38.4	50.2
35mm	56	35.6
50mm	80	25.4
85mm	136	15.1
100mm	160	12.8
150mm	240	8.6

 

[Gazamonk]

I seem to recall a phone app I had once that gave you this info. Anyone ?

 

[ecoleman]

Photopills app has all that data.
also very useful for other Astro information.

 

[wornish]

Stellarium can also show you the field of view against the target you choose. You can enter multiple different lens / sensor size data to allow you to switch between them.

 

[CharleyL]

I think you will find what you want in the "Photographer's Companion" App. It's FREE too. Very handy to have for looking up about everything that I photographer would want. I've been using it for over two years. It comes in many languages as well.

Charley