Gdm f520 crt monitor

We displayed stimuli on a 21-in. Sony GDMF520 CRT monitor (resolution: 1280 × 960 pixels, refresh rate: 100 Hz). Subjects used a headrest located approximately 57 cm from the screen. The screen background was gray (57 cd/m²). An Apple iMac computer running MATLAB 7.1 (MathWorks, Natick, MA) with the Psychtoolbox (Brainard, 1997 (link); Kleiner et al., 2007 ; Pelli, 1997 (link)) and EyeLink (Cornelissen, Peters, & Palmer, 2002 ) extensions controlled stimulus presentation and response collection. We recorded eye movements using a remote infrared video-oculographic system (EyeLink 1000; SR Research, Ltd., Mississauga, Ontario, Canada) with a 1-kHz sampling rate, precision of 0.01 deg, and average accuracy of 0.25°–0.5 deg, according to the manual (but see Holmqvist et al., 2011 ; Poletti & Rucci, 2016 (link)). We acquired eye position data with the EyeLink software. We set the “Heuristic filter” option to off to obtain the raw data.

Stimuli presentation was performed using an Apple Mac computer (Cupertino, CA) running a Bits# display controller (Cambridge Research Systems, Rochester, UK), which drove a Sony GDM-F520 CRT monitor (Tokyo, Japan) at an 85-Hz frame rate. Experimental software was written in MATLAB (MathWorks, Natick, MA) using the Psychtoolbox (Kleiner, Brainard, & Pelli, 2007 ).
The experiment was conducted in a dark room. Head position was stabilized using a chin rest, at a distance of 130 cm from the screen. A 4.9° black X, with its central 3.4° (diagonal) blank, guided fixation in all experiments. Experienced observers viewed the stimulus monocularly by their dominant eye through ophthalmic trial lenses, with the other eye patched. Naïve participants viewed the screen binocularly and wore their own corrective eyewear.
The monitor spectra were carefully calibrated with a Photo Research PR-650 spectroradiometer (Photo Research, Chatsworth, CA), and gamma correction was achieved by loading in a look-up table to the Bits#. Luminance of the mid-gray (x = 0.289, y = 0.315) background was 75 cd/m² (approximately 2.6 log Td). Temporal frequency of the flickering stimuli was calibrated by an oscilloscope driven by a fast photocell.