You got… something on your face… right there

tiger longwing Heliconius hecale profile
Part of my routine is photo sorting, which involves examining each image I take for (my standards of) quality, and discarding those which fail to make the grade. One standard is critical sharpness, so images get reviewed at full resolution, which means they’re much larger than the monitor size and I’m only seeing small excerpts at a time.

While doing this for the images taken at the butterfly house recently, I spotted a curious detail on what I believe to be a tiger longwing (Heliconius hecale,) but there’s a few species that could possibly fit this color pattern so I stand to be corrected. In the profile perspective above it can just barely be made out, but let’s go in closer to see it a little better.

tiger longwing Heliconius hecale with encrusted proboscisIt’s a good thing that butterflies don’t have their mothers around when they reach this phase, because that’s a sight sure to make mom whip out her handkerchief and start scrubbing away while her kid squirms and grimaces – I’ll let you try to imagine an insect with its compound eyes squinted shut. I can only assume this is some coating from the interior of a flower bloom, because I’ve never seen a butterfly that liked eating paste, but I’m not a lepidopterist either. It does make me question what purpose this would serve, and if it’s possible for that stuff to get into the tip of the siphon proboscis and block it, effectively preventing the butterfly from eating. And now we come to the mental image of a butterfly blowing its nose.

I’ve seen that eye pattern in several species, and while I think it’s a ‘false pupil‘ effect, it might also signify ommatidia that have different purposes, like seeing more into the ultra-violet spectrum. Then again, that white stuff might be cocaine – it does come from poppies, after all. This would also explain why butterflies cannot fly in a straight line.

We return (reluctantly I admit) to being serious for a moment, to talk about the cropping of the closeup here. There are a lot of different ways to crop the image and see the crucial detail, and a lot of ways that make it awkward. The one I chose makes use of the corners, places the crucial bit in that ‘thirds‘ region, and portrays a subtle diagonal emphasis right across the image. The first crop I tried was a bit too wide and the facet I was illustrating thus smaller and harder to see. I won’t say this is the ‘perfect’ way of doing it – I don’t believe there’s such a thing anyway – but it’s what worked for me, and considerably better than many choices. Little decisions like this can help your images more than you might think.