Sony

The Sony A7 III may be the worst nightmare Canon and Nikon have faced in years: a full-fat, full-frame camera for just $2,000. This could cut into their bread and butter -- professional/prosumer cameras -- at a time when smartphones have already devastated the traditional consumer point-and-shoot.

But apparently Canon and Nikon are just about ready to fight fire with fire by announcing their own full-frame mirrorless cameras.

Nikon Rumors reported this week that Nikon will announce not one, but two full-frame mirrorless cameras by the end of this month, shipping in August, with a 25-megapixel model rumored to cost under $3,000 complete with a lens. (A separate 45-megapixel model may cost around $4,000 with lens.)

They'll reportedly have a relatively compact form factor (like the Sony A7) and 5-axis stabilization (ditto), plus a new mirrorless lens mount.

Nikon had previously said it would bring a high-end mirrorless camera to market by spring 2019.

Not to be outdone, Canon Rumors reported Thursday that Canon will also have two full-frame mirrorless cameras coming "before the middle of 2019," including a 30.4-megapixel model and perhaps a 24-megapixel model, each of which shoots 4K video.

As a Canon DSLR fan, I'm just hoping a new Canon camera might be compatible with my existing lenses. "One trusted source told us that the full frame mirrorless camera and EF mount problem has a "sexy" solution," writes Canon Rumors, but it's not clear what that means yet.

Nikon declined to comment. Canon didn't immediately reply to a request for comment.