Yes, you really will need straight comparos of the B25 with this one, at f4-f5.6-f8, to get a feel for what is happening. The bronco shot straight on would be good - a planar surface so curvature is visible, and magnification is large enough to pick apart quality differences. Deeper but closer scenes also work very well, from close to say 50-75m. Bear in mind Zeiss went for cross frame performance in the B25, so centers are a little below the L21 but the corners are a little better.
Roger's MTF show quite a deal of mid frame curvature compared with the Canon zoom - both at 24mm; and for the Sony zoom at 24mm compared with that same lens at 35mm.
petermendelson's concerns on p13 are unresolved, by the look of it. What he saw at f8 is what you could expect of fine structures shown by the two lenses in the outer frame, the zoom also has more CA than ideal and the B25 shows residual but well-controlled CA, caused by a little Sonnar style astigmatism.
Missed a request from Gerry re the Loxia 35. Below is the MTF at best aperture for that lens - f5.6. Really strong center to short edge ('12' on the bottom scale), then very good until '16-17' (same scale). This is just short of the wide edge ('18' or half of the 36mm frame - 2 sides), then the tan lines (dotted) from all three sets of lines decline sharply. By '18' it's all over. I'd say it's good for a crop the equal of 40mm if it is a true 35mm lens. This kind of design was very common in film days.
I did post the Sony 24-70 at 24mm with and without distortion corrected in Capture One a page or so back. It's has some good distortions at 24. I'll look at the rest of the focal lengths and I did also upload the Raws from this morning Big Bronco wall test. Link again a page or so back. I'll process them in morning and post but certainly your free to download and work with them. BTW I'm happy to upload any Raws from these tests. I want you all to be informed as to know what your buying it not. I want these answers too. I'm ruthless on these kinds of tests because I purposely go for worst case on backgrounds and such. I call it ugly testing and it tells me more than pretty girl shots.
Can't believe I'm going to say this but if you asked me this some years ago I would most certainly say primes . This zoom is pretty special though as I have not found a major fault in it or a focal length that's secretly weak either. 70 maybe the weakest but I want to process the files first. But anyway I'm starting to think zoom and compliment with primes when more funds are available . Now me I have no choice I have the VC 15, Loxia 21 , zoom and the GM 85 and that's it. So I do need a prime between 21 and 85. Also for failure , backup mode too. But I have the zoom now and right now I'm pretty stinking smitten with it . It's got character I have not seen in a zoom and that is usually the big difference between a prime and zoom. Well speed also but the zoom runs very parallel with primes and that makes me reevaluate my stigma for primes. I maybe changing my spots. Lol
Moroni wrote:
That would be great! I need to decide wither to keep my primes or go with the zoom. Can't afford both.
Maybe GM Photography would be nice enough to do a quick side by side? I think he owns every lens ever made. ;-)
p.22 #10 · Sony FE 24-70mm f/2.8 GM Rolling Review
Great analyses.
"By '18' it's all over". True, that's when high astigmatism takes control.
By the time you start cropping the image for excellent corners, as might as well just get the Loxia 50.
philip_pj wrote:
Missed a request from Gerry re the Loxia 35. Below is the MTF at best aperture for that lens - f5.6. Really strong center to short edge ('12' on the bottom scale), then very good until '16-17' (same scale). This is just short of the wide edge ('18' or half of the 36mm frame - 2 sides), then the tan lines (dotted) from all three sets of lines decline sharply. By '18' it's all over. I'd say it's good for a crop the equal of 40mm if it is a true 35mm lens. This kind of design was very common in film days....Show more →
p.22 #12 · Sony FE 24-70mm f/2.8 GM Rolling Review
Still waiting on my 24-70 GM to arrive (no official word yet as to when it is scheduled to ship...) but in the interim the good news is that my 85 GM is supposed to arrive tmrw. Woo Hoo.
Anyone read the "real world" review of the 85 GM posted HERE
p.22 #13 · Sony FE 24-70mm f/2.8 GM Rolling Review
Fred Miranda wrote:
Great analyses.
"By '18' it's all over". True, that's when high astigmatism takes control.
By the time you start cropping the image for excellent corners, as might as well just get the Loxia 50.
Or maybe 40mm or so, thanks Phillip thats what I feared. Doesnt seem like its worth the £900 it costs in the uk, no auto diaphtagm either. Its no better than my 40mm Ultron SL (which is nice out to the edges at 5.6 and 8, at infinity) and cost less than half the Loxias price, and there are quite a few 'heritage' 35s for slr that would do at least as well. I can use a Nikon G to Sony adapter too and get 'preset' diaphragm.
p.22 #14 · Sony FE 24-70mm f/2.8 GM Rolling Review
Okay continuing on with my Big Bronco wall test which we all agree is boring as heck but a vital test to check corners and center sharpness on lenses which I do this test on every lens I buy which means in another words< Im constantly doing this test. But thats a another story all together. Here i am just going to work on the Sony 24-70 GM 2.8 alone and than if we want to compare to some other lenses we can do that. But let me be honest right out of the gate. This lens is kicking butt and taking numbers. Im a little bit shocked as the results are very strong for a zoom across all the focal lengths. Sure maybe a few weak areas in focal length but it is not by much and 24mm might be the strongest and will smoke a lot of primes. I know will it beat a Batis 25. Its pretty scary how good 24mm is and it flows uphill with 29mm, 35 and 50. Lets look at the images and see what you all think.
First lets show the distortion at 24mm which is pretty strong but checking 29mm images there is very very little so I would suggest at 24mm you have your lens profiles on.
Okay that is the scene and here are the upper left crops . On the 24mm i did put in the right crop as there has been some discussion about upper right softness. Comparing the left and right at 2.8 it looks dead even on this copy at least. Yahoo I have a good copy and let me remind everyone this is pixel peeping to the max. these are 100 percent crops 1200x1200
I could not be more impressed with the 24mm setting its even good wide open in the corners
STOP STOP STOP
I should not say this but Im going to anyway. My opinion take it for what it is worth. I have NOT seen any 24mm lens in this system of lenses pick any one you want but nothing I have seen is this good in the corners at 24mm. I love the Batis 25mm but the corners from memory are not this good starting at 2.8. If that answer the Batis 25mm question so be it and Im not a zoom guy and I love the Batis 25 so this runs polar opposite of my preferences but we also need to consider the center crops which I will post after this. Moving on
29mm getting really good at 5.6
35mm is pretty darn strong here . 5.6 looks really good and this is my most frustrating focal length in the primes. Now a lens that will beat this at 2.8 in the corners is the Tamron 35mm SP 1.8 that lens is very flat field and very sharp but with that its also a clinical lens. But also a very nice landscape lens to have when you need like 2.8 to shoot in the wind for speed. Sony FE 35 1.4, VC 35mm 1.7, Sigma 35mm F 1.4 its more like starting to get decent at 5.6 and F8 as the optimum. They have more filed curvature. The Sony 35mm 2.8 I just had a bad copy so my comments would not be valid on it
This one is tough I love love the Loxia 50mm F2 and the question does this zoom equal or beat it. It actually may beat it here but I think if you need a prime when you don't want to take this along the Loxia 50mm is the number one pick in my mind to have and if your like me and have this huge gap between 21 and 85 primes than either a great 35mm or the Loxia 50mm makes the most sense . Lots of options here on which way you want to look as well do you want the same rendering as the zoom which everyone that has the zoom today is saying the same thing it just renders amazingly well. Tough call here
At 70mm I had a little tough time focusing as I was pushed back all the way to my car and i was having this magnify issue going off without me touching the lens so be careful here as my center crops will show 2.8 there is a big difference when I hit F4 which I feel I was slightly off given my casual shots even handheld 70mm at 2.8 on center where really sharp. So be careful on this one but it is very minor.
Now you will notice some CA going on here at the 70mm mark. Looks to go away completely at F8 and given maybe my focus error this could be better at F5.6 so be careful again on this one. For me past 50 Im grabbing the 85 1.4 no question. But thats me.
p.22 #18 · Sony FE 24-70mm f/2.8 GM Rolling Review
The 55 is a special lens and at 1.8 its hard to beat. I would not sell the 55 1.8 to buy the zoom simple because its nice to have 1 or 2 very fast lenses in the kit when you really need it. 2.8 is nice but to be honest this is not the easiest to shoot in low light handheld. I did it last night and you need to be a rock. Now we always have higher ISO to turn too and the A7rII can do ISO 6400 really nice IMHO. But to me its nice to have 1 or 2 fast lenses to compliment this zoom. And I would say that with any style of shooting from landscape to people its always nice to have something very fast to work with. Now ready to post here are the center crops and wide open this thing rocks. It gets tough but remember 1.4 to 2.8 is two stops of speed as well so you have to be careful with this type of zoom which is heavy when handholding. I m good at it but Im experienced and thats not a plug or anything like that. Far from it but good technique is essential here. Also don't ever forget how useful a monopod is as almost everyone never considers it.
p.22 #19 · Sony FE 24-70mm f/2.8 GM Rolling Review
GMPhotography wrote:
Can't believe I'm going to say this but if you asked me this some years ago I would most certainly say primes . This zoom is pretty special though as I have not found a major fault in it or a focal length that's secretly weak either. 70 maybe the weakest but I want to process the files first. But anyway I'm starting to think zoom and compliment with primes when more funds are available . Now me I have no choice I have the VC 15, Loxia 21 , zoom and the GM 85 and that's it. So I do need a prime between 21 and 85. Also for failure , backup mode too. But I have the zoom now and right now I'm pretty stinking smitten with it . It's got character I have not seen in a zoom and that is usually the big difference between a prime and zoom. Well speed also but the zoom runs very parallel with primes and that makes me reevaluate my stigma for primes. I maybe changing my spots. Lol
The Canon 24-70 2.8II did the same to me. I was blow away by the quality of that lens which for me was the first zoom to outperform a few primes I had. And now according to Roger's preliminary testing, the Sony is even better! My only reservation is the size and weight, which makes primes still the best choice for traveling stealthy :-)
BTW: Thanks for the continued excellent real world testing Guy! Very much appreciated.
p.22 #20 · Sony FE 24-70mm f/2.8 GM Rolling Review
You are welcome and yes the zoom does have some bulk its really not as bad as some would think and perfectly acceptable on the camera it actually feels good but again I am very old school and shot much heavier and bulky gear for years so I am used to that. I shot Medium Format digital for several years thats big stuff so want to be careful how i respond to this weight bulk thing. Everyone thinks Sony was supposed to be small and stealthy and yes it is but we pay a price for outstanding fast lenses and zooms because physics won't change because the body got smaller its still full frame. But let me say I have a Tenba Copper 13 inch SLIM bag this will fit in one slot or on camera easily along with my VC 15, L 21 and GM 85 and I could even stack with a Loxia 50 and maybe another small lens plus all the crap that goes with it. Always think system when carrying as well. I don't really mind it but I understand some will. And its really no different from Nikon, Canon or any other 24-70 mid range zoom. These are workhorse lenses and this one is just flat out outstanding. I have all kinds of new thoughts now.
BTW I have not shot the newer canon zoom but again i want all native AF so its either this or the Sigma 24-35 with the new adapter and that lens tested really well too . I think I loaded those raws as well so that is worth a look. I personally like the Sony better for bokeh , rendering, bokeh balls and onion rings plus this Sony is not only sexy to look at it is sexy to handle. So Im staying with this but the Sigma with adapter is 1250 I believe so that is a option but its limited to 35mm longest but you do pick up a stop at F2. Unique lens
I returned mine as I decided to jump on this now since I was still within my return period on the Sigma , why I jumped sooner than later on this. Just easier on me than selling stuff which is really getting old on me.
Its pretty scary how good 24mm is and it flows uphill with 29mm, 35 and 50. Lets look at the images and see what you all think. 
