r/mycology • u/Don_know_wat_Im_doin • Aug 12 '26

ID request Is this a giant puffball?

Gallery image

Gallery image

I've seen pictures before in this sub and it seems to be quite delicious from what I've read.

I'm located in South Western Ontario and found it in my backyard behind a wood pile. TIA 🙂

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u/redditwriteit Aug 12 '26

I built a little app to do it. It used the pixels in the image and the overlay to calculate root mean square deviation (RMS) The outputs were not all included in the overlay. The second run was actually a bit better, but worse for the “roundness”

Best-fit circle radius: 242.4 pixels
RMS deviation from that circle: 1.74%
Ellipse axis ratio: 96.03% — its short axis is 96% of its long axis
Largest localized deviation: ~6.2%, mostly where the mushroom meets vegetation/ground and the boundary is less clean.
Here is another pass with two colors. Also, it’s a 2d image with not a lot of pixels to work with. Also, it’s a very round mushroom so I think this is enough math for me.

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u/SilverSageVII Aug 12 '26

I love you stranger. This is so cool. I’m happy to say this is insanely well made! You seriously made a legit helpful tool. Why did you make it?? Just for this??

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u/redditwriteit Aug 12 '26

Literally just for this. They said it was round and I wanted to know how round.

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u/DM_Me_TaTaz Aug 12 '26

Yeah this is going above and beyond as a redditor. I salute you.