Why are there no wide aperture zooms for Canon RF-S crop sensor cameras ? 22 April 2023

This BIF pic was made with the little RF-S 55-201mm lens on an EOS R10. This combination works rather well in the right conditions.

I quite often see complaints on user forums that there are very few wide aperture zooms for Canon crop sensor (EF-S, EF-M, RF-S) cameras. There was an EF-S 17-55mm f2.8 zoom introduced in 2006, but this was an exception. I owned and used one of these for several years and found it to be a good lens on the EOS 20D and 40D cameras I had at the time.  However the RF mirrorless mount has ushered in a new wave of compact full frame camera bodies and compact zooms to match.

Here is a visual comparison of the EF-S 17-55mm f2.8 for Canon APSC bodies with the current model RF 24-105mm f4 L for full frame RF mount bodies.

 I think the photo tells the story well enough here.

The APSC DSLR kit on the left is larger, heavier, has a smaller zoom range and smaller effective aperture than the current model full frame kit on the right.

Simply stated making large aperture zooms for crop sensor bodies does not make much sense when we can have a full frame kit with about the same size, mass, price, effective focal length and effective aperture.

I think Canon’s product development people understand very clearly where their crop sensor offerings fit into the RF mount catalogue. 

Simply stated, most  RF-S bodies and lenses are smaller, lighter and less expensive than most full frame offerings. That is their selling point which I think will appeal to many camera buyers.

The lenses achieve their advantage mainly by offering a smaller actual and effective aperture range than most full frame equivalents.

The next photo shows what a dramatic difference effective aperture makes to the size, mass and price of a lens.

 The EF-S APSC 55-210mm lens on the left actually has a greater zoom range than the RF 100-300mm f2.8 L on the right. The dramatically larger size of the big white L lens is due mainly to it having a larger aperture.  Price of the R10 kit, AUD1,741. Price of the R3 with 100-300mm L kit AUD23,194.

Summary

Within their size and aperture range constraints each of Canon’s RF-S lenses to date does an excellent job of making high quality photos. They are limited in their ability to capture sport and action in low light and also in their ability to render backgrounds softly out of focus.

Those who need to photograph high speed, low light, indoor sports with softly blurred backgrounds have plenty of options available from the full frame catalogue.

The trade-off is that those options are larger, heavier and much more expensive.