lens speed

G Lindzey , Jan 27, 2017; 12:52 a.m.

I have always tended to buy the fastest lenses I could (given avaiabiity and affordability) for a given focal length and camera. This was partially based on the ease of focusing a 35mm SLR film camera with a fast lens over a slow lens.I am currently thinking of moving to a mirrorless system camera (specifically the fuji x-t2) and I started wondering if the electronic viewfinder was brighter with faster lenses or if the electronics compensated for slower lenses so that the image remained the same brightness. Does anyone know if there is a difference in brightness in the evf for different speed lenses?

thanks

Leszek Vogt , Jan 27, 2017; 01:33 a.m.

Come to think of it, I never noticed any difference between F1.4, 1.8, 2.8 and even higher. If I judge it by Large Format, and ground glass has to be taken into account, anything lower (numbers) than F8 is fine, tho F12 would be somewhat problematic.

Les

Don Bright , Jan 27, 2017; 03:10 a.m.

This would depend on two modes. 1. In screen mode, Preview EXP./WB IN MANUAL MODE EXP/WB PREVIEW EXP.WB: ON OR OFF. Set to on.2. Also on the shutter speed dial if in manual mode, I like too go to X on the dial, then use the front command dial in 3rd stops, you can visualize the screen darkening or lightening in this mode, therefore: If for a test sake you set a shutter speed with a f4 lens open at f4, then replaced that lens with a 1.2 lens open to f1.2, keeping the same shutter speed, you would indeed see a brighter screen because of the faster lens variant.

Source: lens speed