Sky Division, Peterson Engineering Corp.								www.peterson-web.com
		Eyepiece Comparison for use with a 10" f/10 SCT
10" f10 has a	2540	mm focal length
Magnification = telescope FL / EP FL
Actual field of view (in degrees) = (Dia of eyepiece field stop X 57.3) / Telescope focal length
(Field stop and focal length measurements must be in same units.  The 57.3 factor converts from radians to degrees)
Exit pupil size = EP fl / scope focal ratio
Meade 2" Schmidt thread aperture is only 38 mm (1.5" dia)
Alternative calculation for actual field of view = Apparent field / Mag										Alternate
										calc for
				Apparent	Actual					actual
			Dia of EP	field of	field of	Exit pupil	Eye		Approx.	field of
			field stop	View	View	size (mm)	Relief	Tube	Price	view (min)
Eyepiece	EP FL	Mag		(degrees)	(minutes)
Meade 4000 Plössl	56	45	49.0	52	66	5.6		2"	$     200	69
Meade Super Wide	40	64	45.0	67	61	4		2"	$     300	63
Meade Super Wide	32	79	38.1	67	52	3.2		2"	$     240	51
Meade 4000 Plössl	32	79	29.0	52	39	3.2		1.25"	$     100	39
Meade 4000 Plössl	26	98	23.0	52	31	2.6		1.25"	$       80	32
Meade Super Wide	24.5	104	28.0	67	38	2.45	20	1.25"	$     180	39
Meade 4000 Plössl	20	127	18.2	52	25	2		1.25"	$       80	25
Meade Super Wide	18	141	21.0	67	28	1.8	17	1.25"	$     150	28
Meade 4000 Plössl	15	169	13.6	52	18	1.5		1.25"	$       80	18
Meade Ultra Wide	14	181	20.0	84	27	1.4		1.25"/2"	$     300	28
Meade Super Wide	13.8	184	16.0	67	22	1.38	10	1.25"	$     140	22
Meade 4000 Plössl	9	282	9.7	52	13	0.9	10	1.25"	$       80	11
Meade Ultra Wide	8.8	289	13.0	84	18	0.88		1.25"/2"	$     240	17
Meade Ultra Wide	6.7	379	9.8	84	13	0.67		1.25"	$     200	13
Meade Ultra Wide	4.7	540	6.8	84	9	0.47		1.25"	$     170	9
ClearVue 2" 30mm	30	85	44.8	80	61	3	22 mm	2"	$       99	57
ClearVue 2" 15mm	15	169	22.0	80	30	1.5	17 mm	2"	$       89	28
Panoptic	41	62	46.0	68	62	4.1	27	2"	$     500	66
Panoptic	35	73	38.7	68	52	3.5	24	2"	$     365	56
Panoptic	27	94	30.5	68	41	2.7	19	2"	$     330	43
Panoptic	22	115	25.0	68	34	2.2	15	1.25"/2"	$     280	35
Panoptic	19	134	21.3	68	29	1.9	13	1.25	$     240	31
Panoptic	15	169	17.1	68	23	1.5	10	1.25	$     210	24
Nagler type 5	31	82	42.0	82	57	3.1	19	2"	$     620	60
Nagler type 5	26	98	35.0	82	47	2.6	16	2		50
Nagler type 4	22	115	44.3	82	43	2.2	19	2"	$     445	43
Nagler type 5	20	127	27.4
Nagler type 4	17	149	24.3	82	33	1.7	17	2"	$     370	33
Nagler type 5	16	159	22.1	82	30	1.6	10	1.25"	$     320	31
Nagler type 4	12	212	17.1	82	23	1.2	17	1.25" or 2"	$     340	23
Nagler type 6	9	282	12.4	82	17	0.9	12	1.25"	$     280	17
Nagler type 6	7	363	9.7	82	13	0.7	12	1.25"	$     280	14
Nagler type 6	7	363	9.7	82	13	0.7	10	1.25"	$     220	14
Nagler type 6	5	508	7.0	82	9	0.5	12	1.25"	$     280	10
Radian	18	141	18.3	60	25	1.8	20	1.25"	$     228	26
Radian	3	847	3.3	60	4	0.3	20	1.25"	$     228	4
UO Konig Mk 70	40	64	46.0	70	62	4	20	2"	$     200	66
For reference, moon has a 1/2° disk, Pleiades is 2°, North American Nebula is 3°
Bold green text denotes eyepieces that are vingetted without an EyeOpener
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