Fred, obviously, there is a difference between the wide open aperture and what you consider the optimal aperture, f/7.1 in your test images but the difference is really minor, IMHO. Impressive!
AGeoJO wrote:
Fred, obviously, there is a difference between the wide open aperture and what you consider the optimal aperture, f/7.1 in your test images but the difference is really minor, IMHO. Impressive!
Yes and at 105mm, f/4 vs. f/7.1 shows the biggest difference. I would say this lens is great from wide open and that's to the very corners.
Something else I noticed. The 12-24/4 is somewhat 'parfocal', which means, I can just focus at infinity and zoom in and out without having to refocus. The 24-105/4 does not follow this trend. Every change of focal length requires refocusing. This is not a negative as that's something unique to the 12-24 G.
bjornthun wrote:
What do the corners look like at 24mm with the new 24-105/4?
My initial impression is that the 24-105/4 is stronger from 28 to 85mm.
24mm and 105 are still great but not outstanding and perhaps better than the 12-24 @ 24mm.
I didn't test for field curvature and 24mm could have some. I will check this tomorrow.
I know that 35mm is free of field curvature. Here are some crops at 1:1.
This is outstanding for a zoom wide open.
Looks very good, bright and contrasty, cuts the UV well. Dr Nasse was of the opinion that mid zooms should be best in the middle of the range. The ends are kind of a bonus to this way of thinking. If it's varifocal, that's another trade off for the performance profile, like the hard clipping at the wide end. Sales of the fast 24-70 may have suffered had this one preceded it.
So far it looks really good doing the runway stuff and some low light work. See if I can post some. I’m in heavy shooting mode right now. I think today only about 4K and guess what I actually got a good GM 70-200 rental
At 35mm, the extreme corners look noticeably better at f/4 compared to f/5.6, f/6.3, f/7.1 or f/8.
For this initial test, I had IBIS and AF set to off and focused at f/4 and for the other apertures, I just closed down the iris without refocusing.
The weird part is that the center and mid-field improve slightly when stopping the lens down but the extreme corners get worse (less resolution!)...if it's focus shift, it should affect the entire image and stopping the lens down should mask field curvature instead of making it worse...like I wrote, it's puzzling to me and I will re-test this tomorrow. I only see this happening at 35mm.
If it's not focus shift or field curvature...Could it be diffraction? I'm not sure...I see a noticeable difference from f/4 to f/5.6.
Here is a sample at f/4 and f/7.1 (1:1 crops)....I'm all ears.
GMPhotography wrote:
I wonder if it’s a element group shift at that focal length.
If that was the case, wouldn't all apertures look bad for that FL?
All I did was close down the aperture from f/4 to f/7.1 and as I wrote only the extreme corners look worse at f/7.1. There is actually improvement in the other areas of the field.
Fred Miranda wrote:
If that was the case, wouldn't all apertures look bad for that FL?
All I did was close down the aperture from f/4 to f/7.1 and as I wrote only the extreme corners look worse at f/7.1. There is actually improvement in the other areas of the field.
Stop it down in manual, magnify to check the center focus and then move out to the edges and see if the focus shifted there by refocusing.
jamato8 wrote:
Stop it down in manual, magnify to check the center focus and then move out to the edges and see if the focus shifted there by refocusing.
You are saying it could be focus shift. I will test this tomorrow. It's odd because I don't see this with any other FL.
With the other focal lengths, except for 105mm, I don't see any improvement at the extreme corners when stepping the lens down, and that's checking at 1:1.
Fred Miranda wrote:
Got a break from the rain today and tested my 24-105/4 G copy a little bit.
It's very well centered at 24mm and 50mm. At 105mm is only slightly decentered for one of the opposing corners. (My test is brutal though and even the best primes are not perfect)
I consider this a very well-centered copy for a zoom.
Manual focus seems to be very accurate and pleasant to use. It's linear and almost as good as the real thing.
I didn't do an aperture sequence yet and only tested it wide open. So far, I'm impressed by the level of resolution and contrast. There is a noticeable drop at the long end (105mm) but extreme corners look sharp thorough the entire range "wide open". That's impressive.
I didn't check LaCA or any other aberration in detail yet since it's still cloudy here (low contrast) but I can tell that CA won't be a problem with this lens.
I have a feeling this lens will be an outstanding landscape lens stopped down to f/5.6-8....Show more →
Mind sharing how you obtained the lens? Did you buy it blindly? Tested before buying? Evaluation copy? Pick of the litter by some other means? You seem to get great copies with results that other users can't easily replicate.
It does look good for a zoom, except for the poor color and micro-contrast which, to me, seems to give the pictures a "plasticy" look (although it could also be in part due to the in-camera lens corrections?) Will be interesting to see how it does for flare.
Looks like I'll be getting one as well.
I wish Sony FE put distance scales on their AF lenses. I wonder if anyone else feels the same, (mainly for ease of setting up for focus stacking.)
As mentioned above, filter size is an issue. I started with 100mm sq size Grad NDs for Canon zooms, then with my move to Sony A7, and MF lenses I'd managed to drop down to "A" size, then up to "P" size with recent move to Batis wides. I REALLY don't want to go back up to 100 size with this!
Fred Miranda wrote:
If it's not focus shift or field curvature...Could it be diffraction? I'm not sure...I see a noticeable difference from f/4 to f/5.6.
Here is a sample at f/4 and f/7.1 (1:1 crops)....I'm all ears.
Fred, this looks like it could be very slight camera movement- could also be very slight optical or sensor stabilizer movement as well.
pdmphoto wrote:
Mind sharing how you obtained the lens? Did you buy it blindly? Tested before buying? Evaluation copy? Pick of the litter by some other means? You seem to get great copies with results that other users can't easily replicate.
It does look good for a zoom, except for the poor color and micro-contrast which, to me, seems to give the pictures a "plasticy" look (although it could also be in part due to the in-camera lens corrections?) Will be interesting to see how it does for flare.
Nothing fancy here. I just ordered from B&H when they got it in stock a couple weeks ago. As far as color rendering, I agree that it's not as pleasant as the Batis/Loxia rendering mainly because of the green tint bias. I feel that's not a big negative though and easily tweak-able in post. It pretty much matches the 12-24/4G here.
Camera correction is a bit interesting. It looks like the wider FL is about 22mm instead of 24mm before distortion correction but...uncorrected, vignetting seems very high at about 4 or 5 stops. After distortion correction the dark corner spots are completely removed and the lens performs great regarding vignetting. Having said that, it's possible to "fix" the dark corner spots and use the lens as 22mm if really needed since it's not really mechanical vignetting, just very strong vignetting.
I have not tested it for flare yet...waiting for the sun to show up.
johnctharp wrote:
Fred, this looks like it could be very slight camera movement- could also be very slight optical or sensor stabilizer movement as well.
Did you shoot multiples for comparison?
Thanks for the feedback John! I thought about that too but center and mid-field look slightly better at smaller apertures compared to wide open. If it was blur, it would have affected the entire image. IBIS and lens stabilization were also set to off.
I will test more today and post my thoughts on it. Perhaps this lens was optimized for wide open performance.
Hmmm... I have a sharp copy of the 24-70 GM but I don't use F2.8 all that much, it's my walk around/travel lens, mostly for landscape, street stuff. I am wondering if I should trade it for the 24-105... My current travel set include the CV 15, Loxia 21, 24-70 GM and the Batis 135.
My current travel set include the CV 15, Loxia 21, 24-70 GM and the Batis 135.