Flicker photometry: Prior to commencing the experiment flicker photometry was used to adjust the energy of the green and blue-green cues to be approximately
isoluminant with the grey frames.
In theory, this can also be achieved by printing the figure on an
isoluminant background.
In addition, definitive evidence of resolved vision has recently been demonstrated in Diadema africanum with the use of
isoluminant visual stimuli (Kirwan et al., 2018).
One promising study has shown that the existence of blindsight in patients with cortical vision loss can often be predicted by observing subtle pupil size changes (as measured using a pupillometer) in response to the presentation of
isoluminant gratings in the blind field.
Figure 2.a presents the original picture which is made up entirely of isoluminant colors (i.e.
A very obvious and already discussed issue is the problem with the isoluminant colors: how to make them visually perceptible and distinguishable after the greyscale processing, on what criteria an isoluminant component should be brighter or darker.
It basically controls the direction in which the isoluminant colors are being made distinguishable, either by increasing in brightness or in darkness.
But if the chrominance difference happens to be bigger than the luminance, it means that there is the possibility at looking at two isoluminant color values, and so the Challenge1 comes into focus.
2a are constant in chroma and luminance (passing from [H.sub.1]CL to [H.sub.2]CL), leading to isoluminant color schemes.
In contrast, the HCL version shows an isoluminant gray in the desaturated version.
Donk and Theeuwes (2001) failed to observe a preview benefit when new items were
isoluminant with the background.