Any difference between EF and RF lenses?

[maiyaa]

hi guys! i currently have a 60D and an EF-S 18-135mm lens and thinking about upgrading to an RP body. i’m wondering if it’s necessary to get an RF lens to go with it since i have a limited budget? what’s the difference between EF and RF lenses?

thank you very much!

[ebiggs1]

When you are upgrading you upgrade what you can when you can. Of course the R series lenses are better. They are newer and have newer tech. But that does not mean your EF lens are not still good. They are as good as they ever were.

Get the R body and the EF adapter to start.

[AtticusLake]

First off, they're different lens mounts. EF is long flange distance, RF is short flange, so an EF lens will go on an RF camera with an adapter, but NOT vice versa.

Second, your lens is EF-S, which only covers an APS-C sensor. The RP is full frame, so your lens will only cover the middle part of the sensor. I believe that the RP can shoot in crop mode, so it just uses the middle part of the sensor, so that would work. But of course in that case you're not using the full capability of the camera.

Finally, are RF lenses generally better quality than EF ones? It depends on the specific lenses. Maybe a little, in some cases, but EF lenses are still great.

[rs-eos]

In general, RF lenses can offer much improved optics.   I'm also seeing where the widest aperture can also be a bit wider on the RF version of the lens (at a cost of size and weight of course).

I only have one RF lens so far.  An RF 24-70 f/2.8L that I use with my EOS C70.  Though I'm really enjoying using my two EF lenses (50mm f/1.2L and 135mm f/2L) with the 0.71x adapter.   I'll thus be using those EF lenses for years on the C70 after I transition my photo camera to mirrorless.

I will though really miss the smaller size of the EF 50mm f/1.2.  The RF version is larger and heavier!

I also really like the control ring on the RF lenses.

See this page for a good overview of the RF system.

[jrhoffman75]

As has been alluded to, EF and EF-S are two different lens designs.

EF-S was designed to go on APS-C  (so called crop sensor) bodies. They will not mount on full frame DSLRs.

Third party lens manufacturers do not make lenses with an EF-S mount, but they do produce EF mount lens that only cover the APS-C sensor; you will likely get a circular image on a full frame body.

EF lenses will mount on any EOS DSLR.

Either lens will mount on EOS R bodies, but the EF-S lens will still be crop sensor image size, so you lose a significant amount of your pixels.

With an EF-S lens, image size is ~11 MP.

[johnrmoyer]

All of my EF and EF-S lenses work better on my EOS R5 than they did on previous cameras, but that is not a budget option. I have seen rumors of a soon to come EOS R10 that will be a crop sensor camera like the 60D. Maybe that with an adaptor will be a budget option?

[p4pictures]

Yes you can use the EF-S 18-135mm lens on the EF EOS-R mount adapter with the EOS RP. 

Since your EF-S lens was designed for a crop sensor, then the EOS RP detects it's an EF-S lens and switches the 1.6 crop mode on automatically and it cannot be switched off. As written below you'll only get 11.7MP images in 1.6 crop mode. It would be better to get an EF (not EF-S) lens or one of the RF lenses to make full use of the full-frame sensor in the EOS RP. Potential lenses to consider are RF 24-105mm f/4-7.1 IS STM, EF 24-105mm f/3.5-5.6 IS STM or RF 24-240mm f/4-6.3 IS USM 

The recently announced RF-S lenses will fit all EOS R series cameras, but when used on a full-frame model like the EOS R/RP/R5/R6/R3 the camera automatically selects 1.6x crop mode. 

Note that some lenses designed for crop sensors from other brands don't tell the camera they are crop lenses and you may see some significant vignetting. I tried some lenses in the past on my old EOS R, and wrote about my results on my blog https://www.p4pictures.com/2019/06/eos-r-crop-lenses-aps-c/ 

[johnrmoyer]

It appears that all of the EF-S lenses will work with the EOS R10 and EOS R7. The EOS R10 will have more pixels on the subject than the EOS RP when used with an EF-S lens.

https://www.usa.canon.com/internet/portal/us/home/about/newsroom/press-releases/press-release-detail...

[mikemilton]

You can absolutely continue to use your existing lenses. As has been pointed out, ‘crop’ lenses will still need to use less of the sensor. I have your lens and have used if for some time on cinema cameras. It has a number of limitations for cinema (such as focus breathing) but can still be a cost-effective (small and light) lens.

My guess is that you will really want a full frame lens sooner than later. The RF lenses are worth their extra price (IMHO) and are a better long term investment than EF mount lenses. The ‘kit’ lens (rf 24-105 f4) is a good initial choice. 

[blekenbleu]

RF lenses could in theory excel near infinity, when elements can be closer to mirrorless sensors.
For macro and other close focusing, RF lens rear elements may have nominally the same distance as do EF.
Whether optical quality improves because of better glass or grinding formulae or degrades
because of cost cutting (e.g. more polymers, less metal) is up for grabs.
Beyond generalizations, check specific lens tests e.g. MTF graphs.