Data of All My Telescopes and Eyepieces (Comparison Table)

Visual Power (Magnification), True Field of View, and Exit Pupil for Different Focal Lengths of Eyepieces

The following table comprises data for all the eyepieces that I ever owned.

Telescope		Focal Length of Eyepiece (mm)
Magnification*
	Focal Length (mm)	4	5	6	7	9	10			12	15	16	20	24	25		26	28	30	32	35	40		56
PS72	432	108.00	86.40	72.00	61.71	48.00	43.20			36.00	28.80	27.00	21.60	18.00	17.28		16.62	15.43	14.40	13.50	12.34	10.80		7.71
TLAPO1027	714	178.50	142.80	119.00	102.00	79.33	71.40			59.50	47.60	44.63	35.70	29.75	28.56		27.46	25.50	23.80	22.31	20.40	17.85		12.75
*Heritage 76*	300	75.00	60.00	50.00	42.86	33.33	30.00			25.00	20.00	18.75	15.00	12.50	12.00		11.54	10.71	10.00	9.38	8.57	7.50		5.36
Heritage 100P	400	100.00	80.00	66.67	57.14	44.44	40.00			33.33	26.67	25.00	20.00	16.67	16.00		15.38	14.29	13.33	12.50	11.43	10.00		7.14
Heritage 114P	500	125.00	100.00	83.33	71.43	55.56	50.00			41.67	33.33	31.25	25.00	20.83	20.00		19.23	17.86	16.67	15.63	14.29	12.50		8.93
*Heritage P130*	650	162.50	130.00	108.33	92.86	72.22	65.00			54.17	43.33	40.63	32.50	27.08	26.00		25.00	23.21	21.67	20.31	18.57	16.25		11.61
*PDS150/*D. 6"	750	187.50	150.00	125.00	107.14	83.33	75.00			62.50	50.00	46.88	37.50	31.25	30.00		28.85	26.79	25.00	23.44	21.43	18.75		13.39
Dobson 6"	900	225.00	180.00	150.00	128.57	100.00	90.00			75.00	60.00	56.25	45.00	37.50	36.00		34.62	32.14	30.00	28.13	25.71	22.50		16.07
Dobson 6"	1200	300.00	240.00	200.00	171.43	133.33	120.00			100.00	80.00	75.00	60.00	50.00	48.00		46.15	42.86	40.00	37.50	34.29	30.00		21.43
*Dobson 8"*	1200	300.00	240.00	200.00	171.43	133.33	120.00			100.00	80.00	75.00	60.00	50.00	48.00		46.15	42.86	40.00	37.50	34.29	30.00		21.43
*Dobson 10"*	1270	317.50	254.00	211.67	181.43	141.11	127.00			105.83	84.67	79.38	63.50	52.92	50.80		48.85	45.36	42.33	39.69	36.29	31.75		22.68
*ETX 90/EC*	1250	312.50	250.00	208.33	178.57	138.89	125.00			104.17	83.33	78.13	62.50	52.08	50.00		48.08	44.64	41.67	39.06	35.71	31.25		22.32
Skymax-102	1300	325.00	260.00	216.67	185.71	144.44	130.00			108.33	86.67	81.25	65.00	54.17	52.00		50.00	46.43	43.33	40.63	37.14	32.50		23.21
Skymax-127	1500	375.00	300.00	250.00	214.29	166.67	150.00			125.00	100.00	93.75	75.00	62.50	60.00		57.69	53.57	50.00	46.88	42.86	37.50		26.79
Celestron C5	1250	312.50	250.00	208.33	178.57	138.89	125,00			104.17	83.33	78.13	62.50	52.08	50.00		48.08	44.64	41.67	39.06	35.71	31.25		22.32
Celestron C5R	787.5	196.88	157.50	131.25	112.50	87.50	78.75			65.63	52.50	49.22	39.38	32.81	31.50		30.29	28.13	26.25	24.61	22.50	19.69		14.06
Celestron C8	2032	508.00	406.40	338.67	290.29	225.78	203.20			169.33	135.47	127.00	101.60	84.67	81.28		78.15	72.57	67.73	63.50	58.06	50.80		36.29
Celestron C8R	1280	320.00	256.00	213.33	182.86	142.22	128.00			106.67	85.33	80.00	64.00	53.33	51.20		49.23	45.71	42.67	40.00	36.57	32.00		22.86

True Field of View (°)**
Apparent Field of View (°) >		82	68	60	82	52	42	72	80	52	52	82	52	65	42	52	70	56	70	52	69	52	68	52
	Focal Length (mm)	4	5	6	7	9	10	10	10	12	15	16	20	24	25	25	26	28	30	32	35	40	40	56
PS72	432	0.76	0.79	0.83	1.33	1.08	0.97	1.67	1.85	1.44	1.81	3.04	2.41	3.61	2.43	3.01	4.21	3.63	4.86	3.85	5.59	4.81	6.30	6.74
TLAPO1027	714	0.46	0.48	0.50	0.80	0.66	0.59	1.01	1.12	0.87	1.09	1.84	1.46	2.18	1.47	1.82	2.55	2.20	2.94	2.33	3.38	2.91	3.81	4.08
*Heritage 76*	300	1.09	1.13	1.20	1.91	1.56	1.40	2.40	2.67	2.08	2.60	4.37	3.47	5.20	3.50	4.33	6.07	5.23	7.00	5.55	8.05	6.93	9.07	9.71
Heritage 100P	400	0.82	0.80	0.90	1.44	1.17	1.05	1.80	2.00	1.56	1.95	3.28	2.60	3.90	2.63	3.25	4.55	3.92	5.25	4.16	6.04	5.20	6.80	7.28
Heritage 114P	500	0.66	0.68	0.72	1.15	0.94	0.84	1.44	1.60	1.25	1.56	2.62	2.08	3.12	2.10	2.60	3.64	3.14	4.20	3.33	4.83	4.16	5.44	5.82
*Heritage P130*	650	0.50	0.52	0.55	0.88	0.72	0.65	1.11	1.23	0.96	1.20	2.02	1.60	2.40	1.62	2.00	2.80	2.41	3.23	2.56	3.72	3.20	4.18	4.48
*PDS150*/D. 6"	750	0.44	0.45	0.48	0.77	0.62	0.56	0.96	1.07	0.83	1.04	1.75	1.39	2.08	1.40	1.73	2.43	2.09	2.80	2.22	3.22	2.77	3.63	3.88
Dobson 6"	900	0.36	0.38	0.40	0.64	0.52	0.47	0.80	0.89	0.69	0.87	1.46	1.16	1.73	1.17	1.44	2.02	1.74	2.33	1.85	2.68	2.31	3.02	3.24
Dobson 6"	1200	0.27	0.28	0.30	0.48	0.39	0.35	0.60	0.67	0.52	0.65	1.09	0.87	1.30	0.88	1.08	1.52	1.31	1.75	1.39	2.01	1.73	2.27	2.43
*Dobson 8"*	1200	0.27	0.28	0.30	0.48	0.39	0.35	0.60	0.67	0.52	0.65	1.09	0.87	1.30	0.88	1.08	1.52	1.31	1.75	1.39	2.01	1.73	2.27	2.43
*Dobson 10"*	1270	0.26	0.27	0.28	0.45	0.37	0.33	0.57	0.63	0.49	0.61	1.03	0.83	1.23	0.83	1.02	1.43	1.23	1.65	1.31	1.90	1.64	2.14	2.29
*ETX 90/EC*	1250	0.26	0.27	0.29	0.46	0.37	0.34	0.58	0.64	0.50	0.62	1.05	0.84	1.25	0.84	1.04	1.46	1.25	1.68	1.33	1.93	1.66	2.18	2.33
Skymax-102	1300	0.25	0.26	0.28	0.44	0.36	0.32	0.55	0.62	0.48	0.60	1.01	0.80	1.20	0.81	1.00	1.40	1.21	1.62	1.28	1.86	1.60	2.09	2.24
Skymax-127	1500	0.22	0.23	0.24	0.38	0.31	0.28	0.48	0.53	0.42	0.52	0.87	0.69	1.04	0.70	0.87	1.21	1.05	1.40	1.11	1.61	1.39	1.81	1.94
Celestron C5	1250	0.26	0.27	0.29	0.46	0.37	0.34	0.58	0.64	0.50	0.62	1.05	0.84	1.25	0.84	1.04	1.46	1.25	1.68	1.33	1.93	1.66	2.18	2.33
Celestron C5R	787.5	0.42	0.43	0.46	0.73	0.59	0.53	0.91	1.02	0.79	0.99	1.67	1.32	1.98	1.33	1.65	2.31	1.99	2.67	2.11	3.07	2.64	3.45	3.70
Celestron C8	2032	0.16	0.17	0.18	0.28	0.23	0.21	0.35	0.39	0.31	0.38	0.65	0.51	0.77	0.52	0.64	0.90	0.77	1.03	0.82	1.19	1.02	1.34	1.43
Celestron C8R	1280	0.26	0.27	0.28	0.45	0.37	0.33	0.56	0.63	0.49	0.61	0.61	1.03	1.22	0.82	1.02	1.42	1.23	1.64	1.30	1.89	1.63	2.13	2.28

Exit Pupil (mm)
	Focal Ratio	4	5	6	7	9	10			12	15	16	20	24	25		26	28	30	32	35	40		56
PS72	6	0.67	0.83	1.00	1.17	1.50	1.67			2.00	2.50	2.67	3.33	4.00	4.17		4.33	4.67	5.00	5.33	5.83	6.67		9.33
TLAPO1027	7	0.57	0.71	0.86	1.00	1.29	1.43			1.71	2.14	2.29	2.86	3.43	3.57		3.71	4.00	4.29	4.57	5.00	5.71		8.00
*Heritage 76*	3.95	1.01	1.27	1.52	1.77	2.28	2.53			3.04	3.80	4.05	5.07	6.08	6.33		6.59	7.09	7.60	8.11	8.87	10.13		14.19
Heritage 100P	4	1.00	1.25	1.50	1.75	2.25	2.50			3.00	3.75	4.00	5.00	6.00	6.25		6.50	7.00	7.50	8.00	8.75	10.00		14.00
Heritage 114P	4.4	0.91	1.14	1.37	1.60	2.05	2.28			2.74	3.42	3.65	4.56	5.47	5.70		5.93	6.38	6.84	7.30	7.98	9.12		12.77
*Heritage P130*	5	0.80	1.00	1.20	1.40	1.80	2.00			2.40	3.00	3.20	4.00	4.80	5.00		5.20	5.60	6.00	6.40	7.00	8.00		11.20
PDS150/D. 6"	5	0.80	1.00	1.20	1.40	1.80	2.00			2.40	3.00	3.20	4.00	4.80	5.00		5.20	5.60	6.00	6.40	7.00	8.00		11.20
Dobson 6"	6	0.67	0.83	1.00	1.17	1.50	1.67			2.00	2.50	2.67	3.33	4.00	4.17		4.33	4.67	5.00	5.33	5.83	6.67		9.33
Dobson 6"	8	0.50	0.63	0.75	0.88	1.13	1.25			1.50	1.88	2.00	2.50	3.00	3.13		3.25	3.50	3.75	4.00	4.38	5.00		7.00
Dobson 8"	6	0.67	0.83	1.00	1.17	1.50	1.67			2.00	2.50	2.67	3.33	4.00	4.17		4.33	4.67	5.00	5.33	5.83	6.67		9.33
*Dobson 10"*	5	0.80	1.00	1.20	1.40	1.80	2.00			2.40	3.00	3.20	4.00	4.80	5.00		5.20	5.60	6.00	6.40	7.00	8.00		11.20
*ETX 90/EC*	13.89	0.29	0.36	0.43	0.50	0.65	0.72			0.86	1.08	1.15	1.44	1.73	1.80		1.87	2.02	2.16	2.30	2.52	2.88		4.03
Skymax-102	12.75	0.31	0.39	0.47	0.55	0.71	0.78			0.94	1.18	1.26	1.57	1.88	1.96		2.04	2.20	2.35	2.51	2.75	3.14		4.39
Skymax-127	11.81	0.34	0.42	0.51	0.59	0.76	0.85			1.02	1.27	1.35	1.69	2.03	2.12		2.20	2.37	2.54	2.71	2.96	3.39		4.74
Celestron C5	10	0.40	0.50	0.60	0.70	0.90	1.00			1.20	1.50	1.60	2.00	2.40	2.50		2.60	2.80	3.00	3.20	3.50	4.00		5.59
Celestron C5R	6.3	0.63	0.79	0.95	1.11	1.43	1.59			1.90	2.38	2.54	3.17	3.81	3.96		4.12	4.44	4.76	5.08	5.55	6.34		8.88
Celestron C8	10	0.40	0.50	0.60	0.70	0.90	1.00			1.20	1.50	1.60	2.00	2.40	2.50		2.60	2.80	3.00	3.20	3.50	4.00		5.59
Celestron C8R	6.3	0.63	0.79	0.95	1.11	1.43	1.59			1.90	2.38	2.54	3.17	3.81	3.96		4.12	4.44	4.76	5.08	5.55	6.34		8.88

Italic: I do no longer own this telescope/eyepiece; italic: added for comparison purposes; 2" eyepieces (see below) are not usable at some of my telescopes, but the tables are only meant as a general information in case that you own similar eyepieces and/or telescopes...

Magnification: Yellow: low (30-50 x); magenta: medium (80-100 x); violet: high (150-200 x - and more); red: beyond maximum usable magnification.
For use of magnifications, see here.

Field of View: Allows to predict whether an extended object can be fully captured or whether adjacent objects can be observed together.

Exit pupil: Determines the brightness of the image in the eyepiece; values in magenta cells are either too small (< 1 mm) or too large (> 6.4/7 mm); yellow background: best for galaxies (about 2-3 mm).
For more information on the exit pupil, see here.

*) Can be doubled with a 2 x Barlow lens or focal extender.
**) The full moon is almost exactly 0.5° (= 30') in diameter.
?) Sky-Watcher lists a field of view of 42° as default value for typical amateur eyepieces (please, replace by the actual values if known).

About My Eyepieces

See here for photos of my current eyepieces.

2" eyepieces:

5 mm Hyperion wide angle eyepiece (68°) from Baader; can be used with 1.25" as well as 2" (with 2" also usable with a focal length of 22.5 mm)
26 mm SkyWatcher 26mm Panaview 2" Okular (70°) (originally: 26 mm Meade QX wide angle eyepiece (70°, Plössl) for 2" (bought with the 10" Dobson))
28 mm Sky-Watcher LET 28 - 2" overview eyepiece (56°, bought with the 6" Newton)
30 mm TSWA30 wide angle eyepiece (70°, Erfle) for 2" (bought with the 8" Dobson)
35 mm TS ED35 - 2" UFL overview eyepiece (69°)
40 mm Lacerta ED - 2" UFL overview eyepiece (68°)
56 mm Omegon SuperPlössl - 2" overview eyepiece (56°)

All other eyepieces are 1.25" eyepieces:

The 6 mm eyepiece is a HR planet eyepiece (60°); newer models (2016) are specified with field of view of 58°; I gave it away.
The 4 mm, 7 mm, and 16 mm eyepieces are TS UWA = TS ultra wide angle eyepieces (82°).
The 10 mm eyepiece with a viewing angle of 70° is made by Explore Scientific; I gave it away in March 2018 (for space reasons not listed in the table above).
The 10 mm eyepiece with a viewing angle of 72 ° is made by TeleVue (Delos, bought used).
The 10 mm eyepiece with a viewing angle of about 80° is made by University Optics (Wide Scan, bought used, exact data unknown, given away).
The 10 mm and 25 mm eyepieces came with the Sky-Watcher Heritage P130 and 100P and the Skymax-102 OTA (the 25 mm eyepiece is called "wide angle"; probably, these are not Plössl type, but Kellner type eyepieces).
The 24 mm eyepiece with a viewing angle of 65° is a used TeleVue wide angle eyepiece.
The 25 mm eyepiece with a viewing angle of 52° is a Celestron Plössl eyepiece that was delivered with the C8 (given away).
The 40 mm eyepiece is called Pro-Optik (Plössl; given away).
All further 1.25" eyepieces (9 mm, 12 mm, 15 mm, 20 mm, 32 mm; field of view 52°) belong to the Revelation eyepieces set (Plössl); the 32 mm eyepiece is a Digiscope eyepiece with wide view and T-mount for digicams (a similar or identical eyepiece called TS Super View 32 mm is sold by Teleskop-Service). I gave away all these eyepieces, except for the 32 mm eyepiece.
I gave away a 9 mm Plössl eyepiece, which was delivered with the GSD 680 telescope, because it was more or less identical to an eyepiece of the same focal length from the Revelation eyepiece case.

Italic: No longer in my possession