EF-RF Lens Mount Adapter versus Control Ring Lens Mount Adapter

[LoveWeims]

I purchased a Canon EOS R7 mirrorless camera but still own and love the Canon EOS 20D,  The 20D has a nice 18-55mm EF-S f3.5-5.6 lens on it that I want to use on the R7 also.  I always liked that lens, and I don’t see an equivalent RF lens and even if I did, I would prefer to use the lens I own anyway.

So a mount adapter seems to be the right solution, but now I am confronted with a choice.  The product called simply a “lens mount adapter” is $129.99 at Best Buy and then there is the product called “Control Ring Lens Mount Adapter” for $199.99 at Best Buy.  Currently, I only have the ONE  EF-S lens.  I am a life-long photographer but only recently (since retirement) have I had the time  to delve into this kind of photography.  My goal is not to go the cheap route just because I don’t know what I don’t know at this point in my journey, but I also don’t want to buy something that won’t grow with my increasing knowledge and hopefully, expertise,

Not to mention I’m disappointed with the pricing of RF lenses…

So, is the more expensive option the better purchase for someone who wants equipment that is ready for someone who might still have to learn how much she really needs it?   

[Tronhard]

Hi again:
As an aside, Weims are cool dogs!

First of all, while the EF-S 18-55 from the 20D might be a favourite focal range and it is a great moderate all-purpose range on a crop-sensor body, it will show its age on the new and far more demanding sensor of the R7.  There have been multiple iterations of this lens over the years, with on-going improvements in focus accuracy and speed, IQ, coatings etc.  The final version of this was the STM version that has fly-by-wire control, offering instant focus and silent operation: both of which are great for working with animals, events or video.

The more MP a sensor captures, the more flaws in optics, focusing or technique it will show.  To give you a relative idea of the pixel density issue: the 20D has an 8.2MP sensor, while the R7 has a 32.5MP unit - that is a massive difference and the R7 is a challenging sensor density to begin with.

If you really want to adapt your existing lens to a R-series body, my first advice is buy ONLY a Canon adapter: otherwise the results are unpredictable (we get lots of issues with them), and you can violate the terms of your warranty if their use results in damage to the camera.   

For the majority of people, the basic EF-RF adapter works fine.  Still, any adapter comes at a cost, which is fine if you are going to adapt other EF lenses to your R7 body but, if not, then the money you would invest could go towards a native RF-S lens that will play better with the R7 and later bodies. 

As a life-long photographer, I am sure you are cognizant that the optic has a greater impact on image quality than the camera body, and an investment in glass usually well outlasts that of the body itself. My point is that investing in a decent lens for your camera is not a waste, and putting an older optic will not return the same benefits as putting a lens designed for the platform and sensors you are actually using.

Right now, Sigma have released a licensed RF-S 18-50mm f/2.8 lens that has gained a solid reputation when used on other MILCs such as Sony.  It's not cheap, but it's the best general-purpose lens out there at the moment and covers a similar range to your beloved 18-55.  First, it has superior optics and a fast, constant aperture of f/2.8 which is superior to both your existing EF-S and the RF-S equivalents.
See: 18-50mm F2.8 DC DN | Contemporary | Lenses | SIGMA Corporation (sigma-global.com).  There are videos at:
Sigma RF 18-50mm F2.8 DN RF Review: The Best APS-C Option on Canon? (youtube.com)
FIRST Sigma lens for Canon RF! 18-50mm f2.8 vs RF-S 18-45mm review (youtube.com)

If you want the best start towards great photos, then get a decent optic - it will greatly reward your investment.

While the Sigma does not have image stabilization in the lens, the body does have IBIS and this should provide the level of stabilization you are used to.

[LoveWeims]

Thanks Trevor - you have convinced me to save my $$ for the best Canon lenses i can get when I finally settle on what i am really going to need.  I read the entire review of the Sigma and had two thoughts:

1.  Is Canon going to let  sigma make the “budget” versions of its RF lenses?  If so, it would be better for me to use the 3 RF lenses i have now (only the macro is an L/pro lens - but i know i love bugs, flowers, random patterns Mother Nature creates…etc). And save my $$ for when I am better educated.

2.  As Brian (below) suggests, i am headed outside NOW to take the exact same photos i took with the Canon 20D with my kit lens (RF 18-150mm)and compare results.  I bought that lens because i thought it to be the best for my known shooting preferences.

and YES!  Weims are amazing and because they are so active and versatile, I wanted a camera to capture dog sport events (e.g. ability, which we do together as a team).  Shooting wildlife and dog sports are challenges I have a strong desire to do well!

Appreciate all your help!  My profile photo is Forrest, my 4 yo male).  He is my 5th Weim, 2nd male, and a sweet and very active boy!

Best regards - Gail

[Tronhard]

Hi Gail:

Thanks for your response.   I  couched my response based on your expressed preference for the 18-55-ish lens range, otherwise I would have suggested the RF-S18-150 too.  I didn't see a listing of your current RF lenses, but absolutely, if you have the RF 18-150, I would stick with that for the time being and get used to using the R-series bodies.  There is a lot to them, especially in terms of focus and tracking.

Actually, as far as the RF lenses go...  Canon are concentrating on the FF glass right now, and given the number of brilliant Full-Frame bodies they have released that is where their concentration lies. Canon have let Sigma make the premier lenses for APS-C bodies and seem to have stuck (for the time being at least) to their cheaper kit lenses. They have been under a lot of pressure to release more and more lenses across the board, so this may well be their way of resolving the situation and it is a win for APS-C body users.  Without doubt, the Sigma is a premier lens and the constant aperture of 2.8 is seriously impressive in such a compact optic. If I had an APS-C R body, I would definitely look at them -  I have had quite a few legacy Sigma lenses and they, along with Tamron (who have not released any RF glass yet), are top-end lens makers.

As regards close-up and macro photography...  If you are prepared to save up for the RF 100 L version, it will work well with your APS-C body, but the Field of View will be that of a 160mm focal length lens.  For all lenses (RF and RF-S), when comparing the impact of sensor sizes on what is captured between Canon FF and Canon APS-C you multiply the physical focal length (what's on the lens) by 1.6 to get the field of view the same lens would have on a Full-frame body.

One advantage of using RF lenses is that should you decide to go to a FF body, your RF glass will be fully compatible, whereas any RF-S lenses will not fill the sensor area and thus crop the recorded area back to APS-C size, significantly reducing your image resolution.

I grew up with dogs in the UK, but now where I live it would be cruel to a dog to have them in such a congested area, so I enjoy the dog my niece has when I visit her family.

[p4pictures]

Following on from Trevor's helpful input, I would add that the RF-S 18-150mm "kit lens" is a great match on the EOS R7. It is more than suited to the demands of mirrorless and would be shorter than your old EF-S 18-55mm on a mount adapter, and possibly no heavier either. 

[LoveWeims]

You have hit the nail on the head!  See my reply to Trevor.  Not going to buy a adapter mount at all.  Likely won’t need an 18-55mm lens!