I am cross-posting this in this forum with L-Mount and Adapted Lens Forums as it is relevant to all.Two mounts - four different adapter types compared.These are subjective tests.

Tom Caldwell wrote:I am cross-posting this in this forum with L-Mount and Adapted Lens Forums as it is relevant to all.Two mounts - four different adapter types compared.These are subjective tests.Thanks for that Tom  A lot of effort to do the this

"Black Screen - Dead Camera"Ouch.

Mark Thornton wrote:"Black Screen - Dead Camera"Ouch.I meant “gives black screen and camera locks up”. No damage to camera - works fine with next compatible lens.

> No damage to cameraThank goodness for that.Mark

Thanks for the chart.  I think my expectations will exceed what is possible with an adapter so I think I will sell the Canon 100-400is ii and buy the Sony 100-400GM.

Thanks for this effort and posting Tom.  I think I am going to trim down my Canon collection and already sold the 70-200 f2.8 III.  So that was the bulk of the funds.  Having sold my 300f4 I might keep my 400f5.6.  Definitely want to keep the 135 f2L, that baby is sharp and fantastic and not too heavy.  The 50 is not much money invested and just makes sense to keep whilst I have a body so maybe the 16-35 f4L goes...then I need to figure out what the 45 TS-E could sell for with not too much hassle.Thanks again...Dan

Tom Caldwell wrote:I am cross-posting this in this forum with L-Mount and Adapted Lens Forums as it is relevant to all.Two mounts - four different adapter types compared.These are subjective tests.Great resource, Tom, thanks for taking the time to put this together!I just discovered this thread, thanks to the resurrection bydavid31anddan,providing cross-reference for the L-mount thread here...Canon EF Mount - electronic adapter comparison: L-mount (Panasonic/Sigma/Leica) Talk Forum: Digital Photography Reviewhttps://www.dpreview.com/forums/thread/4504220I can add to this list with a whole bunch of adapted EF glass (Canon's and Sigma's) for both mounts (L-, M43-), though my performance subjectivity may vary from yours. Let me know how/if I can help.Jimmy G

FYI, your results with the two EF 50 variants (II vs STM) are consistent with my EF-to-E experience - the 50/1.8 II is notoriously unfriendly to adaptation (I don't own it, but I have never seen a positive report regarding it), while in my experience, the EF 50/1.8 STM is one of the most adapter-friendly EF lenses out there.  (STM primes in general are).Too bad you don't have the 85/1.8 USM - in my experience, that particular lens sets apart the wheat from the chaff with regards to adapter performance.  Many adapters fail with this lens, only a few adapters work with it.  (Metabones and Sigma MC-11 on Sony are two of the only three I remember working with it - the third was the Viltrox IV which I don't recommend because while it managed to work with the 85/1.8, it failed with the 50STM!)

Tom Caldwell wrote:I am cross-posting this in this forum with L-Mount and Adapted Lens Forums as it is relevant to all.Two mounts - four different adapter types compared.These are subjective tests.Thx 🙏very usefulGaul

gaul wrote:Tom Caldwell wrote:I am cross-posting this in this forum with L-Mount and Adapted Lens Forums as it is relevant to all.Two mounts - four different adapter types compared.These are subjective tests.Thx 🙏very usefulGaulNot complete or up to date. There are likely firmware updates and I now also have a Viltrox EF-L adapter that I have not extensively tested. However if the software house in support has mastered the interface connections to the camera body I might guess that it is the difficulty with the interface protocols with individual lenses that are the gnarly issue.My guess (only) is that without specific testing the Viltrox EF-L adapter would be similarly compatible to their EF-M4/3 adapter.I bought a ultra cheap Jintu EF-M4/3 adapter that was sold MF-Only and of course AF was not supported.  But for EF lenses on M4/3 bodies it gave aperture control on the body and invoked the lens IS system.  MF worked fine of course.  Not sure if it was capable of MF fly by wire EF lenses.  I did test it for that but I have forgotten my conclusion.  In any case I don't think this version of the Jintu is still available for sale.  At the time it was not much more expensive than all manual adapter with iris built into the adapter.But if good AF was not required then there are a horde of really cheap Chinese brands with names like Jintu and Commlite that will give quite good MF support and AF with many lenses even if they are not as compatible AF as the leader brand electronic adapters.  You tend to get what you pay for.  Their build quality is quite ok. This is what you might buy if you are wanting to chance your luck and have a little play without spending too much.Fotodiox does quite well EF-L but I have not had the pleasure of testing one EF-M4/3 (if that exists).If the Viltrox covers the lenses that you are going to use then it can be quite satisfactory.  But if you really want to be able to pick up 'any' EF lens and be well assured that it will work reasonable AF with the adapter on your camera then Metabones is really the only name in the lexicon.Some lenses of course work well on most, if not all, electronic adapters.Furthermore Brian Caldwell (no relation) who is the designer of the focal reduction optics in the Metabones asserts that his 'Ultra' optical set in their adapters is something special and I have no reason to doubt that claim.

Tom Caldwell wrote:gaul wrote:Tom Caldwell wrote:I am cross-posting this in this forum with L-Mount and Adapted Lens Forums as it is relevant to all.Two mounts - four different adapter types compared.These are subjective tests.Thx 🙏very usefulGaulNot complete or up to date. There are likely firmware updates and I now also have a Viltrox EF-L adapter that I have not extensively tested. However if the software house in support has mastered the interface connections to the camera body I might guess that it is the difficulty with the interface protocols with individual lenses that are the gnarly issue.My guess (only) is that without specific testing the Viltrox EF-L adapter would be similarly compatible to their EF-M4/3 adapter.I bought a ultra cheap Jintu EF-M4/3 adapter that was sold MF-Only and of course AF was not supported. But for EF lenses on M4/3 bodies it gave aperture control on the body and invoked the lens IS system. MF worked fine of course. Not sure if it was capable of MF fly by wire EF lenses. I did test it for that but I have forgotten my conclusion. In any case I don't think this version of the Jintu is still available for sale. At the time it was not much more expensive than all manual adapter with iris built into the adapter.But if good AF was not required then there are a horde of really cheap Chinese brands with names like Jintu and Commlite that will give quite good MF support and AF with many lenses even if they are not as compatible AF as the leader brand electronic adapters. You tend to get what you pay for. Their build quality is quite ok. This is what you might buy if you are wanting to chance your luck and have a little play without spending too much.Fotodiox does quite well EF-L but I have not had the pleasure of testing one EF-M4/3 (if that exists).If the Viltrox covers the lenses that you are going to use then it can be quite satisfactory. But if you really want to be able to pick up 'any' EF lens and be well assured that it will work reasonable AF with the adapter on your camera then Metabones is really the only name in the lexicon.Some lenses of course work well on most, if not all, electronic adapters.Furthermore Brian Caldwell (no relation) who is the designer of the focal reduction optics in the Metabones asserts that his 'Ultra' optical set in their adapters is something special and I have no reason to doubt that claim.Hi Tom,In light of the impending DPR diaspora, have you any plans to migrate your extensive research onto another site? Yes, yes, I know I still owe you my EF–MFT data for the above spreadsheet, hopefully I can get a stretch of responsibility-free (and excuse-free!) time to finally finish-off and compile that for you.Best to you going forward, kind sir.Jimmy G

Thanks Tom for all your work here and past question answering for me...much appreciated.Dan

Jimmy G wrote:Tom Caldwell wrote:gaul wrote:Tom Caldwell wrote:I am cross-posting this in this forum with L-Mount and Adapted Lens Forums as it is relevant to all.Two mounts - four different adapter types compared.These are subjective tests.Thx 🙏very usefulGaulNot complete or up to date. There are likely firmware updates and I now also have a Viltrox EF-L adapter that I have not extensively tested. However if the software house in support has mastered the interface connections to the camera body I might guess that it is the difficulty with the interface protocols with individual lenses that are the gnarly issue.My guess (only) is that without specific testing the Viltrox EF-L adapter would be similarly compatible to their EF-M4/3 adapter.I bought a ultra cheap Jintu EF-M4/3 adapter that was sold MF-Only and of course AF was not supported. But for EF lenses on M4/3 bodies it gave aperture control on the body and invoked the lens IS system. MF worked fine of course. Not sure if it was capable of MF fly by wire EF lenses. I did test it for that but I have forgotten my conclusion. In any case I don't think this version of the Jintu is still available for sale. At the time it was not much more expensive than all manual adapter with iris built into the adapter.But if good AF was not required then there are a horde of really cheap Chinese brands with names like Jintu and Commlite that will give quite good MF support and AF with many lenses even if they are not as compatible AF as the leader brand electronic adapters. You tend to get what you pay for. Their build quality is quite ok. This is what you might buy if you are wanting to chance your luck and have a little play without spending too much.Fotodiox does quite well EF-L but I have not had the pleasure of testing one EF-M4/3 (if that exists).If the Viltrox covers the lenses that you are going to use then it can be quite satisfactory. But if you really want to be able to pick up 'any' EF lens and be well assured that it will work reasonable AF with the adapter on your camera then Metabones is really the only name in the lexicon.Some lenses of course work well on most, if not all, electronic adapters.Furthermore Brian Caldwell (no relation) who is the designer of the focal reduction optics in the Metabones asserts that his 'Ultra' optical set in their adapters is something special and I have no reason to doubt that claim.Hi Tom,In light of the impending DPR diaspora, have you any plans to migrate your extensive research onto another site? Yes, yes, I know I still owe you my EF–MFT data for the above spreadsheet, hopefully I can get a stretch of responsibility-free (and excuse-free!) time to finally finish-off and compile that for you.Best to you going forward, kind sir.Jimmy GJimmy, I am not sure which forum if any that I will end up on. I have made a decision not to endorse any forum directly as they are all 'in progress' and the chat is becoming more and more like 'brand loyalty' - 'I joined this one and it must be good'.Frankly from where I sit they are all startups unless they are other older contemporaries of dpreview when we have chosen dpreview as where we wish to be.Basically my eventual choice will be ease of joining, a good interface, more technical with photographs (rather than photographs with chat added), with any advertising, if present, at a level that does not need an add blocker to preserve sanity, free of course (smile) ....In the end it is the membership itself that makes a forum interesting. Maybe it will be the late adopters without agendas that will prove the success of one of the many possibilities?I suspect that it will be many smaller forums that replace dpreview and it might not be the biggest drum band that will succeed best.I also point out that it will be easier to be on a forum without the bugs that will have otherwise to be sorted from a cleanskin startup that has to have original code written. To try and replicate dpreview which was refined over 20+ years from a standing start is an enormous ask, but maybe we can live with fora that has buggy code?Using a tried and proven shell might not make for a clone of dpreview but should be bug-free and useful.Without seeking to endorse this forum I have only joined one at the moment which currently has regularised its name as dprforum.com - but I have not started posting there as I prefer to see out my job as moderator on some dpreview forums until the lights go out.Then I might re-group and check out what is happening. I think that this might be what most current dpreview members will also be doing - despite the influencer threads that are currently thriving.Thank you for your feedback on my spreadsheet. I have purchased a Viltrox EF-L adapter but hardly had the time to test it across my EF lens collection.A few nights ago I used it on a S1 camera body with a Canon EF 200/2.0L lens - seemed to work well at the coalface. In conjunction I had the G9 with Olympus 40-160/2.8 and GX9 with PL 200/2.8 + 1.4 TC. The G9 combination was working best as can be seen by my sample images uploaded. But the other two combos were also very good.https://www.dpreview.com/forums/post/66978245Once settled I will try and get back to updating that spreadsheet. I have a couple of extra EF mount lenses to add and of course firmware might also have been upgraded. I did not compare focal reduction adapters for EF-M4/3 nor have I included any tests from such other adapters as Commlite EF-M4/3 - I have one of them as well.