EF better image than RF on R6, Normal?

[Pauly_6_String]

Hello all.  I just took some test shots to compare IQ with a few lenses at 100mm. Wanted to see how the Viltrox EF-R2 affects IQ if at all.

I used a variety of lenses, RF 24-105, EF 24-105 (1st gen), RF 100-400, Tamron EF 70-200 2.8 G2.

The EF 24-105 was noticeably better than the RF 24-105.  Should that be the case? At f/4 it was way better at the sides. At f/8 both improved but EF was still a touch better.

2nd question, the EF image shows a touch more of the subject. Is that just the fact that that adapter places the lens a bit further from the sensor?

Thanks

[AtticusLake]

As I understand it (I don't have one), the Viltrox EF-R2 Lens Mount Adapter is just a simple adapter -- not a speedbooster.  It has no glass in it, so it can't affect IQ at all.  Really the only way it can screw up is if it holds the lens the wrong distance from the sensor, which would affect your focus.

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@Pauly_6_String wrote:

The EF 24-105 was noticeably better than the RF 24-105.

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There's no specific reason that those 2 lenses should be exactly equivalent.  Often I would guess that the RF version is based on the EF version, but it will be re-engineered to some extent to take advantage of the shorter flange distance, for example.  Often the RF lenses will be better -- cos they're just newer -- but not always; the RF 24-105 could be cost-reduced, for example.

So it *could* just be a quirk of the RF 24-105 lens.  Or it *could* be a defective lens.  I would post a question about that lens specifically (I don't have it) so people with more knowledge can see it and respond.

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2nd question, the EF image shows a touch more of the subject. Is that just the fact that that adapter places the lens a bit further from the sensor?

Generally the focal lengths marked on lenses are fairly approximate.  It's not unusual to see two lenses with theoretically the same focal length give different fields of view.  In fact on most lenses (both primes and zooms) the focal length will change as you rack focus -- this is called breathing, and it can be quite strong.

The adapter makes no difference here -- if it's doing its job right, it's holding the EF lens in exactly the same position it would be if the camera was EF.

[Tronhard]

I have not used the adapter you mention, but as Atticus suggested, it should not be an issue in itself.   

I do have two EF (MkI) and two RF 24-105 (both L lenses).  I note that you do not specifically mention if the RF 24-105 is an L version, but since you mention f/4, I will assume that both the lenses your lenses are L versions.

In my own experience, I have found that the RF versions consistently offer better results than the EF units, which is what one would and should expect from a newer, native RF lens.  There are several videos on You Tube that do direct comparison between the two FWIW and I would recommend reviews by Justin Abbott that have some quite detailed reviews on the RF version specifically.

[Pauly_6_String]

Thanks Trevor. I’ll check out those videos. 

It is the L version but did get it used. The zoom ring got stuck once as in frozen for a couple of minutes then it wasn’t. Strange situation but always had me suspect something was up. 

it has taken good images generally but when I did this comparison I was surprised how much better the old EF performed. 

[Tronhard]

One has to wonder why such a new lens was sold, particularly in the light of the apparent sticking.  It may be that the lens has had some sort of impact, and if that is the case, it is quite possible that an optical element is now out of alignment.  It might be worth having it checked.

[Pauly_6_String]

Yeah, and it was $700 when they were hard to find new. Hard to pass up when all I had was an RF 50 1.8 and a bunch of EF lenses

So just run through the Canon web site support process?

[Tronhard]

I would suggest that's the way to go.  Good luck! 🙂

[Pauly_6_String]

I was just about to try and upload some images to show the comparison. trying to figure out how to do that 

[Tronhard]

The best thing where we need the detail for resolution is to upload the RAW files via a link.   So, put your images on a sharing site and create a link to them that is applied here via the chain (i.e. link symbol to the left of the camera) on this page when in composition mode.

[Pauly_6_String]

The images on the bottom right if I look at the blue book's authors I see a shadow especially at f4.

What do y'all see?  Thanks for looking