EF-S 24mm f/2.8 STM Compatibility with EOS M50 and EOS R6

[Far-Out-Dude]

I have been wanting to try a Prime lens and was thinking of grabbing the Canon EF-S 24mm f/2.8 STM Lens to use with my with M50 (I have the Canon adapter for EF/EFS to M) Two questions I have about it is will everything work with it and also I would like t know when I upgrade hopefully in the Spring to a R6 or better with the adapter that allows EF lenses to be used with RF will it allow EF-S lenses to work with the RF mount at well? Is there any problem anyway with auto-focus working with either of the configurations? I found an article here but it was so long and went into things so techniquly that it was far more confusing than helpful in answering the question especially since it also started naming off mounts from other name brands as well. My other options are the Canon EF 50mm f1.8 STM or the Canon EF 50mm f/1.4 USM Lens I would like something that will work well in lower light and shadows. I took some pictures of a band yesterday and they turned out to me horrible. I normally do not film people ofthen but it looks like something I will be doing more of at least in the Summers. I would love an 85mm L series but it is not in the cards at this time, body first then another L series. Oh how do you deal with people becoming camera shy? The band asked me to take pictures and then when I started to every time I pointed the camera in their direction they would move away.

 

[jrhoffman75]

Just EF-S. EF and RF lenses are full frame. 

[Far-Out-Dude]

Then why did somebody about say efs would not be full frame if I get an R6 later? I am confused. Sorry, just trying to understand.

[deebatman316]

EF-S or RF-S lenses are NOT designed to cover a full frame image sensor or 35mm Film (36x24). There ONLY designed to cover the APS-C image circle (22.5x15). Note RF-S IS NOT a separate lens mount like EF-S is. All RF-S is, an RF Mount lens that projects an APS-C image circle. Thus a Full Frame camera automatically applies a 1.6x crop to avoid vignetting. 

This is what a Full Frame camera sees with an APS-C lens attached. You'll see this same effect if the camera doesn't crop the image.

[jrhoffman75]

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@Far-Out-Dude wrote:

Then why did somebody about say efs would not be full frame if I get an R6 later? I am confused. Sorry, just trying to understand.

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I think they said that the EF-S lenses with an EF-M adapter will fill the full image sensor on an EOS M camera. The image is still cropped as shown in Rick's graphic. An EF lens is also cropped if mounted to an EOS M camera. The portion captured by the sensor is the same for both lenses; it's just that more is lost with a full frame lens.

When you mount an EF-S lens on an R series camera with the adapter the lens doesn't have a large enough image circle to cover a full frame sensor; if nothing is done there would be a somewhat circular image. The camera crops out everything beyond a 4x3 rectangular image. those pixels are gone.

The EF-R adapter is a tool to allow use of one's existing EF and EF-S lenses. One should not purchase an EF-S lens to use on an R body.

[Far-Out-Dude]

Thanks guys, makes me wonder how my 100-400 l series is going to look on a RF camera now. Trying to improve my gear as I can, trying to take a lot of landscape and wildlife and the more I am told the more confused I become to be perfectly honest. I do thank you for trying, my ADD/ADHD makes me a bit dense sometimes, just bare with me please. Does anyone want to tackle why a R6 with less MP than my M50 is considered better than the M50 other than newer tech?

[jrhoffman75]

If its a 100-400L it will be better on an R body. 

[Far-Out-Dude]

Yes it is.

[krahe]

The R6 is a full frame camera, which means it has a much larger sensor. Even if it had the same resolution as the M50, it means that each pixel gets more lens to itself than each pixel on the M50 does. More lens = more light, so the full frame will perform better in low-light conditions than the same lens on an M50. Because the R6 has fewer pixels than the M50, this benefit is extended even more. The larger pixels also make the R6 more forgiving of imperfections in the lens. On the other hand, if you have a very sharp lens and good light, the M50 can capture more detail in a scene compared to an equally sharp lens on the R6 with a focal length that provides the same FOV. But it's not going to be a huge difference, and probably of little practical value, since even 20MP is overkill for most photos unless you're doing some heavy cropping.

[Far-Out-Dude]

Good clear and concise answer, thank you. I have been offered money for my pictures in the past so I want to put out the best images I can which is one of the reasons I am looking to upgrade.