Which would be the Right lens for a mirrorless camera?

First of let's look at the reason, why you are looking for or have bought a mirrorless camera. A lot of Photographers are going for a mirrorless camera because it's light in weight and works as a good travel / every time kind of a camera. If weight is a big consideration in your decision to go for a mirrorless camera, then make sure that you are not adding a very heavy lens to it. That will defeat the whole purpose of going for a lighter camera.

If we consider Sony cameras, as they are at the forefront of innovations in the category of mirrorless cameras besides other brands, there are mainly two walk around full frame lenses - 24-70mm and 24-240mm

It's a general rule, that a lens with a lesser zoom range will always be better in quality in comparison to the one with a bigger zoom range. 24-70 weather f4 or f2.8 will always be a better lens in terms of sharpness and overall quality than 24-240 but then we always tradeoff certain things for others. If we wish to have one walk around lens and are biased towards the longer focal length as well, then 24-70mm focal length lens won't serve the purpose. This is where 24-240 will work as a more versatile lens offering portability as well as the convenience of not changing the lenses and not carrying too many lenses with you.

To make it simpler, if you generally shoot portraits, groups and other stuff closer and around you when you are on a holiday or move out for street photography then go for 24-70mm and if you feel that you often need to zoom in and shoot distant elements, then 24-240 is the right option for you. 

Individually all these lenses are good.

24-240 hands on review

If you are a Photography professional, you might be more inclined towards 24-70mm f2.8 GM but if you are not too fussy about the extra quality you will get with this fast lens and light weight or the convenience of not changing the lenses is the priority, then go for 24-70 f4 or a wide range zoom of 24- 240mm. Both of these lenses wont disappoint you.

You may check a comparison between the two 24-70 mm lenses but a lot of people do not really notice the difference.

Vario-Tessar® T* FE 24-70 mm F4 ZA OSS 

FE 24-70 mm F2.8 GM / Know more about G Master lenses

FE 24–240 mm F3.5-6.3 OSS

Best Full frame 4K mirror less cameras

Zoom or Prime Lenses

Munish Khanna is a Delhi, India based commercial photographer who has successfully trained countless photographer across the globe over the last two decades. Do consider one of the online Photography courses if you are a starter in Photographer or need to further enhance your Photography skills.