
Cheap, or just inexpensive?
Mirrorless cameras do have disadvantages, and these could still limit their take up.
For now, no mirrorless system offers a built-in ND filter, although Canon has taken the interesting step of adding a filter slot to one of its EF to R-mount adapters.
Audio remains limited, with manufacturers favouring a 3.5mm jack; an accessory XLR mount is available for the GH5 series and for the Sony a-series. These are not cheap, however: Sony’s XLR-K2M is £400, Panasonic’s equivalent about £300.
Most video professionals add other accessories to their kits. Additional batteries are essential. The design of mirrorless cameras, with their need to keep to stills camera ergonomics, prevents the use of larger-capacity battery packs. Alternatives include battery grips, and dummy batteries to connect to V-lock, gold mount or other external power sources.
Mirrorless cameras use more power than DSLRs, due to their electronic viewfinders. But mirrorless cameras have no direct support for running off mains power, which is something to consider for producers who film events and other long-form projects.
Then there is the question of recording quality. Although a shallow depth of field and a wide dynamic range makes for great footage, the internal codecs in mirrorless cameras are rarely as effective as those on full-sized cinematic camcorders. The GH5s is still the only mirrorless system with internal 10-bit, 4:2:2 recording in 4K. The Panasonic S1 will have 10-bit via a paid upgrade, although there is also 10-bit (4:2:0) support if users opt to record in h.265.
Finally, camera makers need to address the cooling issues that have caused problems for film makers, especially on longer shoots or in warmer climates. There simply is not the space for the fans, heat sinks and ducting on cameras such as the C300 on a mirrorless system, yet the camera electronics are having to work very hard to process large, high quality images.
“Technology will need to get to a point where the smaller CSC bodies can deal with the processing power and heat dispersion to deal with better codecs and higher frame rates,” cautions Hampton. Until then, film makers are unlikely to move completely over to full-frame mirrorless kits.

Full-frame systems will also have to compete with smaller, but more cost-effective camera lines. Fujifilm is making inroads into the market with its APS-C sensor XT3, the new Blackmagic Pocket Cinema Camera 4K, which uses Micro Four Thirds lenses, is attracting a lot of interest, and the GH5 and GH5s remain contenders.
“The combination of the Panasonic GH5/GH5s’s low price point and a focus on video capabilities, as well as its small size and light weight body, make this model series very popular amongst video content creators,” says Futuresource’s Gill.
“Its smaller sensor arguably puts it at a disadvantage against the Sony A7 series – however, its total cost of ownership is also lower when lenses are considered.” At WEX, Hampton agrees: the GH5 series continues to sell well.
This suggests that video professionals are benefiting from a wider range of camera options. Both full-frame and smaller sensor systems are set to coexist in the market, with each offering a blend of look, practicality and cost – and competition will keep camera makers innovating too.
Next: A film maker’s view