The 15-45 switch.

nnowak wrote:

Jayson A wrote:

nnowak wrote:

Jayson A wrote:

why do lenses with the EF adapter require the lens cap when turning the camera off, but native lenses don’t?

What???

Every time I turn my camera off with an EF or EF-S lens on, it says "Keep the Lens Cap On after Camera is Off", but native lenses don't say that. The camera just shuts off normally. I thought the sensor is aways exposed whether you have the camera off or on since there's no mirror covering it. So why is it important to keep the lens cap on when an EF or EF-S lens is attached vs a native EF-M lens?

Never noticed that before.

My guess it is due to the difference in aperture mechanisms. The EF-M lenses stop down to the smallest aperture when powered down. EF and EF-S lenses are wide open when powered off.

Apparently Canon must be seeing a rash of people starting their mirrorless cameras on fire by mounting giant telephoto lenses and leaving the camera pointed at the sun while sitting on the dash of their car in Arizona in July.

You're closer to the equator than Arizona is. It was a standard warning / precaution for cameras with focal plane shutters in the days before instant-return mirrors and with rangefinder cameras.

EF and EF-S lenses open up to maximum aperture when the camera is switched off so that you can still see through the viewfinder. RF and EF-M lenses stop down to near minimum aperture without power. The Retract lens on power off menu option refocusses them to near infinity. There have been a couple of threads in the RF forum about unexpected melting damage to the plastic surround to the sensor.

In answer to your first question, it doesn't matter about retracting your lens when not using it, provided you're careful with it. The locking mechanism protects it somewhat from being broken by bumps. I always cap and lock my lenses (or zoom my 18-55mm to 18mm) before climbing around things, just as I always fasten my seat belt, it only takes seconds and it's a safe habit to get into.