Picked up the RX100IV to upgrade the ol' "3"... no big surprises or changes, the 4K is nice, but that 5 minute clip length will be a definite downside!

Out of curiosity I ran a couple quick tests - didn't realize the "dual record" function that records a lower res 720P file simultaneous with the 4K one was set to "on"... the camera heated noticeably and quickly, was able to do the first 5 minutes OK, and forged onward with the heat indicator flashing for a second 5 minutes... heat indicator stayed on when I started to play back clips, eventually went away.

Here's where it gets interesting, once I turned off the dual record (significantly reducing the load on processor, buffer and memory writing), heat was a lot less noticeable, still got the heat indicator towards the end of 10 (two back to back 5) minutes, but the heat "issue" was greatly reduced.

Also tried the 1080/60p XAVCS, no apparent heat problems.... too bad they couldn't manage a lower bitrate 4K for those times when one needs "long form" recording.

Otherwise, it's a great little "pocket rocket" for those times when you need great stills and limited duration video and want very high quality.

Thanks for the report Dave. Hardly a device that will excite the professional film maker even if the output quality is remarkable even by today's standards. When asking around about the best wide lens for my A7RII one suggestion was get a RX100IV, save a couple of dollars and have some fun. Good suggestion I reckon.

How do you find the EVF? With the A7RII the EVF dims when one hits the movie button and the AX100 EVF is nothing to write home about. I guess it's related to power consumption/heat and I guess it goes with the 4k territory.

Appreciate your thoughts on the EVF.

Cheers...

Thanks for the tests Dave. Though I got to use the camera on loan a few times I never had the chance to really test it for heating. In the typical environment I work in this heat issue could be critical (outdoor or ambient temperatures often exceed 90F degrees and sometimes closer to 100F). I remember it heating quite quickly too when shooting in the 1080/100p (yours 120p) mode. Not sure if setting the 4K mode to 60Mbps would help extend 4K recording time compared to 100Mbps.

Agreed with the camera being the best fast wide lens for 4K on a Sony body. You save a ton of dough for sacrificing relatively little for what you can get from that US$3,000 7RII + $$ lens if you use it mainly for video.

I'm sure it will be OK for the short clips - 1080p XAVCS seemed to be perfectly happy. I just tested the hi rate 4K, and it was noticeable you really shouldn't try to use dual record, it just adds to the amount of bits running around generating heat! I'll try to run a test on the lower bitrate, but I think it probably shares the 5 minute clip limit internally, though it should be cooler.

Bang for the buck is definitely good, stills look great as always, and the 4K looks very good so far, not bad for a "pocket cam".

The EVF is small, but it does the job, didn't see any dimming? I'm guessing that might be something that could be related to how you've set things - maybe the A7RII shows a brighter image in photo mode, and then switches to show you actual results for however your video is set? In many cases, that would create different results between the two modes? If you're in movie mode, I would think that the display should always be "WYSIWYG"?

Really, one has to keep perspective that the little monster fits in your pocket or tiny bag, and so you've got a powerful capture device you can take anywhere and use anytime. The RX10II is a "better" camera, but not exactly something you stick in your pocket or use discreetly. I'd pick the 10 if I had to choose just one, but the 100 is and has been (I've owned all of the versions) so handy for "casual" use when you want something better than crappy cell phone or P&S quality.

Just wanted to add that I used the camera to record long form 4k fixed on a tripod tethered to an atomos shogun. I'm happy to report that in this configuration there's no overheating issues at all and the battery lasts a lot longer than expected. You can also power it with external USB chargers for very long takes. The prores files also have an amazing amount of detail and the shogun xlr inputs allow for simultaneous internal microphone and external aufio input recording. This is a great little combo for events. :)

Here's another experience:

I shot video over a 1.5-hour session, never turning the camera off except for one 10-second battery change. In that period I shot 14.4 GB's of 4K video at 100 Mbps. The average clip length (my standard shooting) was around 12 seconds. The longest was 26 seconds. I never observed a heat warning or turn off. The setting was indoors in a slightly overheated building (likely 75 degrees F).

An update to the earlier posts...

I installed the "hack" app that bypasses the recording limits, it includes an option to bypass the 5 minute clip length on the M4... but I got the little heat "warning" (not a shut down, not sure if I'm brave enough to try for that!) at about 8 1/2 minutes, camera continued to run and was not overly hot, but definitely had toasty "warm" spots! Ambient indoor temp of around 76 F, screen articulated out from body, and an aluminum grip attached that seems to act a bit like a heat sink...

I'm sure that shorter clips don't pose the collective heating of continuous recording, and want to fiddle with faster SDXC cards to see it that helps (noticeable heat in that area...).

The RX100M4 remains a very capable and handy little camera, as long as one doesn't need longer 4K clips (I would expect the hack to allow longer than 30 minute HD clips, but will have to try to see how long before heat might be an issue....)