The FUJIFILM EVF-TL1 EVF Tilt Adapter does not affect the use of a flash.

Unfortunately, this product is not listed as compatible with the GFX100S.

This will be fully compatible with the GFX 100 but will unfortunately not work with the GFX 100S.

The EVF-TL1 is compatible with the GFX 100 II.

Hi Travis, I find that composing shots on the LCD is not as efficient as looking through a viewfinder. That said the tilting adapter allows for the best ergonomics when looking through the viewfinder for extended periods. Angling it up and looking down while holding the camera below head level is hard to beat for extended periods = less strain on neck and arms. Also when backed to a wall angling it straight up is helpful to get the camera further back. I wish it angled a full 90 degrees sideways like it does in the vertical direction (it only does 45% in the side to side). Also of great importance is that it extends the viewfinder about 1" further back so it acts as viewfinder extender too, no need to press your nose and face into the camera to see through the viewfinder.

No, the FUJIFILM EVF-TL1 EVF Tilt Adapter is only for Fujifilm cameras with detachable viewfinders, such as the FUJIFILM GFX 50S Medium Format Mirrorless Camera and the FUJIFILM GFX 100II Medium Format Mirrorless Camera.

No. This is specifically made for the mount built into the top of the 50S and GFX 100.

You can use the pocketwizard radio trigger with this Tilt Adapter