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What does the EF-S indicator on my C100 Mark II viewfinder indicate?


I just got a C100 mark ii a month ago and I have had the same lens on for a couple weeks but just now noticed the EF-S yellow indicator on my viewfinder/LED screen. What does it mean? I wasn't sure if I accidentally enabled something. 


Not applicable

Do you have an EF-S lens attached to the camera? See this from the manual:

Screenshot 2023-09-26 194511.jpg

 Here is your camera's manual download: 

Rising Star

Some EF-S lenses can have some light fall off at the edges so this setting crops in on the sensor to eliminate it. With the Canon EF-S 18-135mm IS STM lens on my C100 mk2, I haven't noticed any darkening of the edges of the frame so I keep the EF-S setting off.

EOS C100 mk2 with the Canon EF-S 18-135mm IS STM lens - Atomos Ninja 2 - Zoom H2n - Dell 8700 i7-4790 3.6Ghz, 24GB Ram, Win 10, Nvidia GTX 1060 6GB - DaVinci Resolve Studio 18.6.2 - Blackmagic Speed Editor - Presonus Faderport 1


The sensor size on the C100 Mark II is 24.6 x 13.8 mm.  An APS-C sensor should be 25.1 x 16.7mm.  So the C100's sensor is a tad smaller.  Thus, any vingnetting wouldn't be any worse (should actually be a tiny amount better) than if using that same lens on an APS-C photo camera.   So would also leave that setting off.

If instead, the C100's sensor was wider like the EOS C70 (26.2mm), then I could then see the need to have that feature enabled.


EOS 5D IV, EF 50mm f/1.2L, EF 135mm f/2L, 600EX-RT (x6), ST-E3-RT
EOS C70, RF 24-70 f/2.8L IS, EF-EOS R 0.71x
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