Sony has announced two updates to its high-end compacts, resulting the in the RX100 IV and the RX10 II. 

The two models expand on the pro features in a pair of already fantastic cameras. The important modifications are to the 1-in type CMOS sensor at the heart of these cameras. 

The sensor has an attached DRAM memory chip (which Sony claims is a world first) that enables it to process the data it captures faster, meaning that these are consumer compact cameras that will do some amazing things. 

You get 4K video capture at 100Mbps and they're able to do this without pixel binning, so there will be more data in the resultant video than some rivals. Data means detail, so the RX100 IV and RX10 II should be great for shooting high quality video.

But that's fairly conservative compared to the 40x slow-motion video, 1000fps. There are options for 1000, 500 and 250fps and more regular 50 and 25fps. Expect to see more of those fancy dogs bursting water balloon videos on YouTube.

It's not only about slow-mo video. The RX100 IV will let you capture 16fps (14fps on the RX10 II) for an "extended period" according to Sony. That's going to make these great cameras for catching the moment. You'll also be able to select shutter speeds up to 1/32000 sec.

SonyRX10M2_right_bgwh

Both cameras have been enhanced with a new AF system, which is a welcome improvement (if it delivers as promised). Focusing was one of the elements we criticised on the previous models. 

The cameras' designs remains fairly close to the predecessor models. The RX100 IV has the same solid but chic looks as before, with a Zeiss 24-70mm (equiv) f/1.8-2.8 lens on the front. It has the same electronic viewfinder as the RX100 III. 

We love the RX100 III - you can read our full review here - we consider it to be the benchmark for pocketable cameras. We'd expect the RX100 IV to repeat that performance, but expect to pay a princely sum for it.

The RX10 II again has the same body as the previous model, with a Zeiss 24-200mm (equiv) f/2.8 zoom lens on the front.

There's no word on pricing or availability, but for reference, the previous models cost £699 (RX100 III) and £999 (RX10) at launch, so expect that as a ballpark.