I took a number of shots this night using the DA15 with an IR filter on for the first time, and they all have hot spots like this one. I will post more when I have time to process them... I don't think I've used my 49mm IR filter very much, so it could actually be the filter itself. Needs further examination...

swimming "noodle"

the end of swimming "noodle"

Fantastic detail. What a top piece of glass.

Definitely master/mistress of the house!

Can't leave it alone can you ?
Very cool b&w with great bokeh effects.

Great colours, focus and background - but what is it?

Jacaranda very badness (when wet).

I'm happy with the medium view, generally not a pixel peeper. But certainly has potential to be a much more convenient switch than Flickr's. Prefer this colour version.

Don't understand the first DA15 reference? typo? I don't recall seeing any hotspots in other IR shots of yours.