This is interesting. I had the M version of the Metabones IV that I got from Amazon and informed them that this wasn't the latest version so i am sending it back. I got the T version, which only has an additional flocking and now with my 11-24L, it focusses at 24 with ease and at all other lengths. I also noticed that my 100L macro that would focus with the M version will outside about 50% of the time so while it isn't totally acceptable but it didn't work before, so something is different about the T version vs the M version.
The T version I got is also tighter but the M was fine. This one is Tight.
Also I have found that if you move a little while focussing, you get a faster and more sure lock. It is like you are searching a little with it but even like locking on an eye it works as you move the camera back and forth just a little.
16-35 2.8 mark II
24-70 2.8 mark II
70-200 2.8 mark II
300 2.8 mark II
Somehow my 85 1.2 mark I will only work in MF mode even if the lens is turned to AF
I went to shoot some birds today at the local lake to test the 300/2.8 II on A7RII. Holy cow! The results are awesome. These OOC RAW in LR, 1:1 zoom and screenshot taken. I was a fair distance from the birds.
gdanmitchell wrote:
I used to understand the difference in the AF method more clearly, and should probably review them. However, I recall that methods like those in use on the Sony sensor can be very accurate but are not able to as quickly determine the direction of the needed correction (focus closer or farther?) compared to systems typically used in DSLRs. So they can seem to hunt a bit more.
My hunch is that at some point designers will address this fundamental issue by simply speeding up the AF process on such cameras to the point that even though they "hunt," they will do it so fast that the overall performance will be very good.
What you are describing about the camera not knowing which direction to go is true for Contrast Detect AF. As you said CDAF can be made faster given enough compute power and many crop mirrorless cameras now have very fast CDAF in single shot mode.Though it is harder in continuous and video AF.
However it is not just about the direction of AF. PDAF also tells the camera how much the lens needs to move to achieve focus. So the lens can get very close to the final AF position in a single step. CDAF on other hand makes a series of small lens movements and checks AF at each step until it finds the best AF point. Many of the DSLR lenses are not made to support such a continuous stream of small rapid adjustments and thus do not work well with CDAF. This is something you can't improve by just making the in-camera AF process faster since you are lens limited.
The on-sensor PDAF points in cameras like A7rII thus help with both the direction issue as well as the rapid adjustments issue. The problem, as mentioned earlier, though is that the PDAF pixels on the sensor are much smaller than the dedicated PDAF sensors in DSLRs, therefore the sensitivity is lower and thus they are less effective in more challenging stuations.
p.11 #10 · A7RII and Canon lenses AF compatibility
Fboss wrote:
Is it with the Metabones or another adapter ? others have reported AF issues with the 70-200 F4 non-IS + Metabones.
thanks.
It is with the Metabones IV T ; there seems to be some odd experiences between users. 85mm 1.2 mk 1 and the 70-200 F4 non-IS work for some and not others.
It was limited testing and I do intend to give them both a far better workout later. Real world vs static etc.
p.11 #11 · A7RII and Canon lenses AF compatibility
AJSJones wrote:
Kevin Raber reports Tamron 150-600 works well
I first thought it would be EF on MB but he didn't actually specify what mount or adapter, however It is available in A-mount, too.
I'm quite interested in this lens but while reports have been encouraging, they have been incomplete. Kevin Raber reports great AF even at 600mm but we don't know if it's Canon mount with Metabones or Sony A mount with adapter. Other reports have been similar (http://garyhartblog.com/) or refer to A7II. Can anyone out there confirm how good AF is with the Tamron on A7rII and which lens mount/adapter combo was used?
p.11 #12 · A7RII and Canon lenses AF compatibility
Interesting and confusing experience with 'Bigma' - old Sigma 50-500.
1. MB Speedbooster - manual only
2. MB 3 - manual only
3. MB 4 v0.41 - AF-S worked. In decent light - during the day - locked very fast (not birding phtoography fast though) but there was virtually no hunting. However:
a. Even though IBIS was engaged, none of the handheld images appear sharp in the 300-500mm range that I tried. Either IBIS was ineffective or focus was off.
b. The camera routinely crashed when taking a photo - basically I press the shutter, it goes black then reboots (3 crashes in about 10 photos). I blame MB4 as same thing happens with many lenses on A7R for me.
c. After a few crashes, I cannot re-engage AF mode on that lens - it's stuck in MF - but the adapter did not appear to engage advanced mode (which is MF only). This persisted through mounting/remounting lens or adapter, or even pulling battery. Swapping to another lens (70-200 f4 non-IS) re-engages AF, so I wonder if several crashes cause MB 4 to disable support for the lens.
And to reiterate what others said - 24-70 mk2 works like a charm, it locked on focus perfectly in a dim room (had to shoot 1/8s at f2.8, ISO 100) ... and 70-200 f4 works fine with enough light, but not great in a dim environment.
Aug 12, 2015 at 09:15 AM
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p.11 #13 · A7RII and Canon lenses AF compatibility
I think that what seems to be emerging is that more light is needed with Canon lenses and the Metabones adapter than is needed for dedicated AF sensor on the Canon cameras. So, f/2.8 zooms work better than f/4 zooms and the fast primes seem to work well too. Slower lenses seem to work better in good light. This combined with shorter focal lengths work better than longer focal lengths gives a good sense of what lenses work better and what lenses work less well. So take a lens like the 35L and it has everything going for it even though it is an old lenses (short focal length and wide aperture) so perhaps we can see why it works well. Take a lens like the 100-400L Mk II and it has everything going against it. Slow max aperture and long focal length and even though it is new it has everything working against it. Perhaps it isn;t surprising that it doesn't work as well.
So the big question, if this reasoning is correct, is whether firmware can be improved to increase sensitivity to lower light available to the system. I don't know if that will be possible, but if this line of thought is correct it can at least point most people to what lenses and what situations when the AF is most and least likely to work.
p.11 #15 · A7RII and Canon lenses AF compatibility
rji2goleez wrote:
I'm quite interested in this lens but while reports have been encouraging, they have been incomplete. Kevin Raber reports great AF even at 600mm but we don't know if it's Canon mount with Metabones or Sony A mount with adapter. Other reports have been similar (http://garyhartblog.com/) or refer to A7II. Can anyone out there confirm how good AF is with the Tamron on A7rII and which lens mount/adapter combo was used?
I think its save to presume that this is the A mount lens that Michael reviewed with the AE4 adapter on an A7II about a year ago.
p.11 #16 · A7RII and Canon lenses AF compatibility
Another update (all via MB 4 v0.41) ...
Canon 70-200 f2.8L IS MK1
At 70-100mm focus is fast. IBIS is only used during composition, and when lens IS is engaged, IBIS shuts off (as expected I think). At 100-170mm focus is a bit weaker and hunts more, but manual pre-focus hints work. At 170-200mm, I was unable to focus 99% of the time (though I was mostly trying at 200mm range), even in bright light and a very high contrast scene. Pre-focusing didn't work either.
Sigma 15-30mm
Extremely fast focus at any focal length (pretty much as fast as on my 5D2). However, it crashed the camera after 10 or so frames, like 50-500 did. Camera rebooted, and no longer switches to AF mode. What is going on with it I don't know ... also, while it focused fast, none of the images appeared very sharp.
p.11 #17 · A7RII and Canon lenses AF compatibility
dmward wrote:
I think its save to presume that this is the A mount lens that Michael reviewed with the AE4 adapter on an A7II about a year ago.
Probably. But more recently it will be interesting to see if anyone tried the EA3 adapter on the A7rII which relies on the camera's 399 PDAF points rather than the more limited EA4. Similarly, I wonder which works better . . . Tamron A-mount with EA3 vs Tamron EOS with Metabones IV.
p.11 #18 · A7RII and Canon lenses AF compatibility
I had similar flakiness as secondclaw did with a Sigma 85mm f1.4, EF mount, on a Metabones III v30.
AF turns off mysteriously and you have to remount the lens or adapter. Camera crashed a couple of times.
I think there's a compatibility issue with Sigma lenses maybe.
p.11 #19 · A7RII and Canon lenses AF compatibility
ebrandon wrote:
I had similar flakiness as secondclaw did with a Sigma 85mm f1.4, EF mount, on a Metabones III v30.
AF turns off mysteriously and you have to remount the lens or adapter. Camera crashed a couple of times.
I think there's a compatibility issue with Sigma lenses maybe.
I have had trouble with my sigma art lens on the a7r already. Causing freezes. It worked better on the a7rII but it would sometimes switch to MF only. Having to reattach the lens in order to be able to have AF again.
p.11 #20 · A7RII and Canon lenses AF compatibility
jaclarkaus wrote:
Tried updating my Metabones Mk IV with Windows 10 ... no go
Worked fine with my Mac though.
The 24-105 seems to work great, and the 85 1.2 II is faster than on my 5DII ! Go figure...
More testing tomorrow
Unfortunately the amazingly clear photo with the 24-105 inside wasn't much better outside, will still have to compare with the 24-70FE, but the IS does not work with the Metabones IV with the latest firmware. The IS does work (or is claimed to by the camera) with the Fotodiox Pro adapter
It is available in A-mount, too.