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Modelfest static detection treshold targets for Year One.

A. Gabor patches with constant size in degrees.

cos(2 pi f y) exp(-((f x/Sx)^2 + (f y/Sy)^2)/2)
where Sx (Sy) is the standard deviation in cycles. For an octave
bandwidth Sx = 0.56.
Stimuli for estimating the CSF (abour half ocatve steps):
Circular Gaussain envelope of 0.5 deg.
Carrier frequencies:
1) 1.12 c/d
2) 2 c/d
3) 2.83 c/d = 2*r, where r=sqrt(2)
4) 4 c/d
5) 5.66 c/d
6) 8 c/d
7) 11.3 c/d
8) 16 c/d
9) 22.6 c/d
10) 30 c/d

B. Gabor patches of fixed size in cycles:

This group consists of one octave bandwidth gabor patches.
Carrier frequencies:
11) 1.12 c/d
12) 2 c/d
13) 4 c/d
14) 8 c/d
15) 16 c/d
C. Elongated Gabor stimuli for multipole comparisons:

Gaussain envelope of 0.5 deg in x direction and two octaves in y direction..
17) 4 c/d
18) 8 c/d
19) 16 c/d

D. Gabor Stimuli for baguette summation (various aspect ratios):
cos(2 pi f y) exp(-((f x/Sx)^2 + (f y/Sy)^2)/2)
All of these stimuli have a carrier frequency of 4 c/d. The gaussain envelopes
in x or y directions are either 0.5 deg, one octave or two octaves as shown below.
stim envx envy
20) oct oct
21) oct*2 oct
22) 0.5 oct
23) oct oct*2
24) oct 0.5
25) 0.5 oct*2
26) 0.5 0.5

E. Subthreshold summation of Gabor pairs.


(cos(2 pi h1 f y) + cos(2 pi h2 f y)) exp(-f^2 (x^2 + y^2)/2)
stim h1 h2 (harmonics) with f=2 c/deg
27) 1 1*r (r = sqrt (2))
28) 1 2
29) 2 2*r
30) 2 4

D. Multipoles:

M(y) exp(-(x/S)^2/2)
stim M(y) S(deg) [note that this definition of S is different from above]
31) L 1/2
32) D 1/2
where L & D is a very thin line or dipole.
An edge times a circular envelope
33) E(y) exp(-((x/Sx)^2 + (y/Sy)^2)/2) Sx = Sy = .5 deg

E. Gaussains of various sizes.

Several Gaussians: exp(-(x^2 +y^2)/2S^2)
34) S = 30 min. SD
35) S = 8.43 min. SD
36) S = 2.106 min. SD
37) S = 1.05 min SD

F. Collinear Gabors.

38 & 39) A row of 5 collinear Gabors, octave bandwidth, f=8 c/d
with a separation of 5 sigma. Thresholds are be measured for
Gabors both in phase and alternating in spatial counterphase.

H. Windowed 2D Noise.

40 & 41) White 2D binary Noise X exp(-(x^2 + y^2)/2S^2) where S=.5 deg.
These stimuli will have 1 min virtual pixels = 2x2 screen pixels of 0.5 min.
Stimulus 41 is the same as 40 except for new noise pattern on each trial.

I. Oriented Gabor patches:

One octave bandwidth gabor patches with 4 c/d carrier frequency.
orientation (rad)
42) 0
43) pi/4
44) pi/2

J. Plaids:

Two one octave bandwidth gabor patches with 4 c/d carrier frequency.
45) oriented vertical and horizontal
46) oriented horizontal and 45 deg.

K. Miscellaneous:

Each of these patterns will have a 0.5 degree Gaussain envelope.
47) Natural image (San Francisco street scene)
48) Bessel function J0, f=4c/d
49) Checkerboard pattern with 4 c/d horizontal and vertical fundamentals.
50) Disk with 1/4 degree diameter.

The total number of unique stimuli is 45, some are used in more than one category.