Just cross posting from DPR a quick test I did to see how the GM1 does with IR unconverted. These were very quick tests. Sorry, no time to do more. Tested GM1 with 17/1.8 and R72 filter in daylight. Not practical. At F/1.8 Auto ISO went to 3200 and exposure maxed at 1 second. I did not attempt manual exposure to find the actual exposure required. AF wouldn't function and MF would be very difficult, probably impossible with a F/4.0 zoom. Based on this the GM1 has a strong IR filter and will only be usable unmodified if tripod mounted with very long exposures in bright light. This is pretty typical for Panasonic cameras actually. For comparison an E-M5 (which is known to have a weak IR filter) at ISO3200 and F/1.8 gives exposures around 1/50 in the same light with easy AF. So GM1 is probably at least two orders of magnitude "worse" than the E-M5 for unmodified IR use. Not specific to the GM1, but since it is kitted with the GM1: Also did a very quick check (viewfinder/LCD check only) of the 12-32 on a 720nm modified G1. There were no obvious hot spots to be seen at both wide and small apertures and at 12mm and 32mm. Please note that this was a very quick check for obvious hot spotting. It is quite possible there is a more subtle hot spot that might show up in post processing with increased contrast and a more uniform subject. This means the 12-32 is certainly usable for IR but I'm not sure if it is truly clear of a hot spot or loss of contrast. So it is at least "acceptable" I'd say for IR and with more testing might prove to be great.