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Text/Object size scaled with incorrect resolution

Hello - I am trying to display a 1cm tall text. It appears much larger than expected. I have input the size and resolution of the monitor in the monitor center and am calling that monitor in the experiment settings. However, I think the program is treating my monitor like it is lower resolution, but still calculating the text size using the number of pixels determined in the monitor center (giving it many large pixels instead of many small pixels).

If I change the window size in the coder to match the correct monitor size, it tells me:
WARNING User requested fullscreen with size [2880 1800], but screen is actually [1680, 1050]. Using actual size.

I have never had this problem before and am using a new computer. Any suggestions are helpful!

Thanks,
DG

OS (e.g. Win10): Mac OS 10.12.5
PsychoPy version (e.g. 1.84.x): 1.85.2
Standard Standalone? (y/n) If not then what?: Y

How have you determined that your monitor is 2880 × 1800 pixels?

Hi Michael,

To determine that the monitor was 2880 × 1800 pixels I looked at the display listed under “about this mac”. I’m guessing that it is not “acting” like that resolution though. I heard retina displays can reduce resolution for certain programs but also read that they should work with PsychoPy so I must be missing something. :confused:

Thanks,

DG

This just seems a little unusual, as Mac retina screens have two physical pixels per logical pixel, so a retina screen of 2880 × 1800 could be reported as 1440 × 900, but not 1680 × 1050. Do you have two displays, and is it possible that the indexing is incorrect (e.g. referring to display 1 when you actually mean display 0)?

NB I don’t think PsychoPy’s retina support is quite there yet: it treats a retina display as if the physical pixels match the logical pixels, so, while stimuli should be the correct size, they appear more jagged than one might hope.

Check in your devices to make sure that your monitor is not scaled. Basically, if you have a 3840x2160 monitor, set to 3840x2160 resolution, but the scaling is 200%, then it will throw off your monitor representation in psychopy. For new computers that have high resolution monitors, they often leave the factory with some scaling in place so that the icons and text are a comfortable size for the new user.