Formulas

Question 1

Estimated Mag (given acuity)

Answer 1

Acuity Achieved/Acuity Required

Question 2

Spot Task Acuity Reserve

Answer 2

3:1

Question 3

Sustained Task Acuity Reserve

Answer 3

2:1

Question 4

Mnom

Answer 4

F/4

Question 5

Mmax

Answer 5

F/4 + 1

Question 6

Addition

Answer 6

1/WD

Question 7

Mag (given WD)

Answer 7

Old distance/New distance

Question 8

New Acuity

Answer 8

Orignial acuity/Mag

Question 9

New WD required

Answer 9

Original WD/Mag required

Question 10

Contrast

Answer 10

LB - Lo/LB

Question 11

Relative Size Magnification (RSM)

Answer 11

RSM = increased object size/original object size
also
RSM = Acuity achieved/Acuity required

Question 12

Relative Distance Magnification (RDM)

Answer 12

RDM = original object distance/new object distance

Question 13

Reference Seeing Distance (RSD)

Answer 13

-25cm = -0.25m = q

Question 14

Angular Magnification

Answer 14

q - L’/1-dL’

Question 15

Combining different types of mag

Answer 15

times together

Total mag = RDM x RSM

Question 16

Linear Magnification (2 formulas)

Answer 16

M = L/L’

h’ = h x L/L’

Question 17

Telescopes:

Magnification

Answer 17

-Fe/Fo

Entrance pupil diameter/exit pupil diameter

angle subtended at w/ telescope/angle subtended at w/o telescope

Question 18

Calculate tube length

Answer 18

d = fo’ + fe’

F = 1/f’

Question 19

Magnification of Cap

Answer 19

Fcap/4

Question 20

Telescopes:

Total Magnification

Answer 20

Fcap/4 x -Fe/Fo