Doug Kerr
Well-known member
The Fujifilm X100 digital camera uses a "hybrid" viewfinder (essentially the same thing is used in the X100S). It can be operated in two modes:
• As a direct-view optical viewfinder, with (if enabled) overlay of shooting information from a digital display panel. The digital display is also used to generate a "bright frame" which broadly indicates the portion of the scene that will be captured by the sensor (on a "90% coverage basis) (the actual visible part of the scene is substantially larger than that).
• As an electronic viewfinder (EVF), which also can present shooting information.
The direct mode optical viewfinder proper uses the very simple "reversed Galilean telescope" design. This is made practical in part by the fact that this is a fixed focal length lens camera and thus no actual "zoom tracking" of the viewfinder is required.
A half-slivered mirror (actually embedded in a split glass block), interposed between the objective and eyepiece elements of the optical viewfinder proper, is used to introduce into the view the digital display giving the shooting information and presenting the bright frame.
In the EVF mode, a shutter blocks the path from the OVF objective lens, and everything the user sees comes from the digital display, again seen via the half-silvered mirror.
An interesting discussion of the X100 viewfinder system (with nice illustrations) is given here:
http://www.finepix-x100.com/en/x100/hybrid-viewfinder
Further discussion of its rationale is given here:
http://www.finepix-x100.com/en/story/viewfinder
The latter article comments that, in the face of a lens with a FOV corresponding to a 35 mm lens on an ff35 camera (as is the case on the X100), a viewfinder magnification of 0.5 is considered ideal. Thus the design of the X100 OVF gives essentially that magnification (and I assume that the EVF mode gives the same).
Best regards,
Doug
• As a direct-view optical viewfinder, with (if enabled) overlay of shooting information from a digital display panel. The digital display is also used to generate a "bright frame" which broadly indicates the portion of the scene that will be captured by the sensor (on a "90% coverage basis) (the actual visible part of the scene is substantially larger than that).
In the similar X100S, the bright frame is moved based on lens focus distance to take into account parallax, and I think changed in size to take into account change in lens focal length at different focus distances. But I think the bright frame is still on a 90% coverage basis!
I think this is what the user typically sees in the OVF mode:• As an electronic viewfinder (EVF), which also can present shooting information.
The direct mode optical viewfinder proper uses the very simple "reversed Galilean telescope" design. This is made practical in part by the fact that this is a fixed focal length lens camera and thus no actual "zoom tracking" of the viewfinder is required.
A half-slivered mirror (actually embedded in a split glass block), interposed between the objective and eyepiece elements of the optical viewfinder proper, is used to introduce into the view the digital display giving the shooting information and presenting the bright frame.
In the EVF mode, a shutter blocks the path from the OVF objective lens, and everything the user sees comes from the digital display, again seen via the half-silvered mirror.
The change in mode is done with a lever on the front of the camera, evocative of the "mirror lift" or "self-timer" levers found on some classic film cameras.
An interesting discussion of the X100 viewfinder system (with nice illustrations) is given here:
http://www.finepix-x100.com/en/x100/hybrid-viewfinder
Further discussion of its rationale is given here:
http://www.finepix-x100.com/en/story/viewfinder
The latter article comments that, in the face of a lens with a FOV corresponding to a 35 mm lens on an ff35 camera (as is the case on the X100), a viewfinder magnification of 0.5 is considered ideal. Thus the design of the X100 OVF gives essentially that magnification (and I assume that the EVF mode gives the same).
Best regards,
Doug