Is this an optical illusion?

Do you see the cone shape as concave or convex?
@dkbarnett challenged me to do a Black & White abstract.
After a little thought I had a lightbulb moment!!

[Susan Wakely]

@dkbarnett Delwyn this is my attempt at B&W abstract.

[Diana]

What a brilliant idea and shot.

[Shutterbug]

That is so cool. Very nice for the challenge.

[Mags]

I love what you did with it.

[Laura]

Both. Great abstract.

[Leli]

I want to see it concave but it keeps popping out:)

[Bill]

Very clever picture.

[Nina Ganci]

very clever abstract

[Carole Sandford]

Mostly concave, but I can force it to be opposite. Clever!

[katy]

Yes! I see it both ways fabulous abstract photo with that added level of interest

[Renee Salamon]

Brilliant, I see both too

[Babs]

Very clever. I see mostly concave too but when I blink, I see convex

[Kate]

Nice abstract patterns

[Pam]

Brilliant!

[Kathy]

Convex, concave when is the last time I used either of those words. Cool idea for a b&w abstract.

[4rky]

Great abstract and very cool.
See concave unless I make my brain melt trying to make it pop out! :)

[Korcsog Károly]

Very super!

[Peter Dulis]

I like it

[Delwyn Barnett]

How interesting. I see this as concave - but your other image, which I now see is the same subject - I saw as convex!