I have a fairly good camera and a Samsung U32H85X 4k quantum dot monitor here is an image of some serious crosstalk in overdrive mode. Feel free to use this anywhere.
Crosstalk Image
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Crosstalk Image
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Re: Crosstalk Image
Nice photo! A good attempt, which only needs minor tweaks to more-or-less match 1:1 WYSIWYG. The exposure clearly shows crosstalk issues.Naveronasis wrote: ↑04 Jun 2021, 04:21I have a fairly good camera and a Samsung U32H85X 4k quantum dot monitor here is an image of some serious crosstalk in overdrive mode. Feel free to use this anywhere.
Camera Technique Commentary
(from years of experience staring at these photos)
What camera and camera settings are you using? I do observe there’s a slight amount of camera-sensor rolling-shutter scan artifact. Some sensors are rolling scan shutter rather than global shutter.
This can create accidental deviations that make the camera less of a 1:1 match between what the eye saw and what the camera saw — even if they look similar. So I have a hawk eye to see subtle artifacts.
I immediately see this, because crosstalk doesn’t usually do two “identical intensity stair steps” horizontally within the same photo simultaneously — see how the line stairsteps towards the right as you go from top to bottom? In a camera exposure capturing 1 single strobe flash, there should only be one equal-visibility stairstep shift, but I see two, and the only situation that happens is either a longer exposure or a camera-sensor rolling scan).
There can still be 3+ strobe crosstalk positions on a terrible LCD that ghosts over multiple refresh cycles, but with a global shutter, they all overlapped-shift only by 1 frame (i.e. 3+ bad duplicates shifting horizontally by only 1 refresh cycle step, no 2 as in this photo). I see horizontal shift of 2 refresh cycles here, so you either had a long exposure or a slow (multi-display-Hz) rolling scan camera shutter.
Stationary (non-pursuit) crosstalk photography tends to work most WYSIWYG when:
- from a distance (zoomed closeup rather than macro closeup)
- human-eye viewing distance
- using a shutter speed equal (or slightly faster) than one refresh cycle.
Typical camera settings for stationary-photo strobe crosstalk photography: Shutter priority, global shutter usually found in SLR or mirrorless, camera at human view distance typically arm’s length from 24-27” monitor (approx screen size = camera distance), 6500K fixed color temp, fixed focus, manual exposure to exactly 1 refresh cycle (if not exact, round down to the next available shutter length), light amount of optical zoom as needed for detail work. And ISO adjusted to prevent overexposure/unexposure since this is shutter-priority.
The other technique is pursuit photography which is more accurate for an eye-tracking situation, (Camera tracking = eye tracking, while stationary camera = staitonary eyes), which makes the camera less exposure-sensitive (stack multiple refresh cycles in a longer exposure as you slide the camera horizontally), but that speciality technique takes more practice.
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Re: Crosstalk Image
LG v30 1/60th exposure time, 200iso. This is why i loved LG phones... Now I need to find a new brand they have all this unlocked without an outside app.