Legacy 24 mm lenses on the APS-C camera sensor (Fujifilm XT-20)
NOTICE: I am not an English speaker, but English is the language that can make this text reach the widest public,
so I'll do my best!
I have tested a number of inexpensive legacy lenses in time, you can
find some here;
I was going to end my exploration since I now possess some very satisfying parts and I promised not to waste more time. Less tests, more photo!
But... temptation is always behind the corner, so when I found myself in front of a Sigma 24mm in excellent conditions for 12 euro,
I didn't even check for reviews, I just got it!
Later I realized that this is a somewhat rare lens, since though the "Sigma Super Wide II" is well known, my older(?) "Super Wide"
(without the "II") is nowhere to be found. This is the only data that I could possibly
retrieve
here (MTF are provided, too):
lens name: |
Sigma SUPER-WIDE 1:2.8 f=24mm Multi-coated Lens made in Japan MACRO |
angle of view: |
85° |
fish-eye: |
NO |
macro: |
in spite of the lens name, NO |
min focus: |
18cm |
elements: |
8 |
groups: |
7 |
blades: |
6 |
focus: |
manual |
It is a lot easier to find information on the Canon "new" FD 24mm, instead.
here it says:
lens name: |
Canon FD 24mm 1:2.8 LENS MADE IN JAPAN |
angle of view: |
84° |
fish-eye: |
NO |
macro: |
NO |
min focus: |
30cm (0.11x) |
elements: |
10 |
groups: |
9 |
blades: |
6 |
focus: |
manual |
Since I already had a 24mm from Canon, the Canon FD 24mm f/2.8, it was an obvious curiosity that of comparing the two.
In this case, I am performing a quick test at short distance, to evaluate the central sharpness and the bokeh.
Here you can see a front and top view of the Sigma 24mm, instead:
Sparse observations
The construction of these lenses is excellent, I have really nothing to complain about.
After decades, also the barrels are very stable and the focus rings are pleasant to use, smooth and precise. Bravo!
For the test images, thay have been shot at f/2.8 and at f/4. Though the sharpness improves at f/4 for both the
lenses, their difference stays more or less the same, so I omit the images taken at f/4.
A word on colours and aberrations
I have used the "neutral" film simulation of the Fujifilm XT-20; I have the impression that the Sigma
makes the red a bit more intense, while the Canon delivers more saturated blue nuances.
The yellow and green seem to be undistinguishable. In the end, the Canon may deliver a little colder images.
As for chromatic aberrations, there is some fringing in the background (look at the handle of the teapot), but nothing
to lament about the foreground, though this is usually less relevant.
My general impression is that the effect doesn't hit the appeal of the image; also notice that the Minolta MD 50/1.4,
a lens that I hold in high regard, shares similar issues.
Longitudinal CA seems to be totally absent.
Back to the Minolta 50mm, that I am using as a sort of base for comparison, it alters the colour of the bands over and
under the leaves pattern of the teapot, giving them a more greenish cast; the same effect is definitely
less pronounced with the Sigma and the Canon.
I cannot tell how much the camera is responsible for this, but for sure the lenses have some part in it since
their behaviour is not identical.
All considered, from the point of view of chromatic aberrations, the two wide angle items display a very good behaviour.
|
|
fringing with the Canon FD 24mm at f/2.8 |
fringing with the Sigma Super Wide 24mm at f/2.8 |
|
the behaviour of the Minolta MD 50mm |
You can see that the strange green accent is a bit more pronounced with the Canon, the Sigma doing slightly better as for
the fringing (in my opinion) and also better preserves the whiteness of the porcelain; the green effect is even more with
the Minolta, but frankly... is the difference really perceivable?
Quick conclusion
It is hard to compare modern wide-angles, which are usually better from all points of view of their legacy
counterparts, to old lenses, but it is not what I am doing here; I am taking a look at two classic, manual
focus lenses with similar specifications.
But let me take a step back. From the point of view of construction, the old lenses, indeed, can be much better(!),
given the employment of a lot of metal.
Also, cheap modern lenses can be behind also by their optics; for instance, I recently tried the 7artisans
55mm f/1.4 and I must say that I definitely prefer most of the old 50mm to it; for wide-angles, though,
the difference between sensors and films become more obvious and modern optics usually do from better to much better,
but again, cheap glasses may not be that good at all.
With APS-C, anyway, at times I like the rendering of old lenses a lot, and I must say that I like both the Canon FD
24mm and the Sigma Super Wide MC 24mm.
The test confirms what can be found browsing the Internet if you take into account what is said of the Sigma sibling,
the Super Wide "II", which is probably very very similar.
At short distance and large aperture (f/2.8), the lenses share good centre sharpness, the Canon doing definitely better, but
it is more a matter of micro-contrast, so digital editing can shorthen the gap.
Leaving the central area of the APS-C sensor, the Canon shows very low vignetting, good sharpness but a somewhat busy bokeh;
the Sigma suffers in terms of sharpness but has a better bokeh, possibly because of the inferior sharpness; also the light
fall-off is more evident in the Sigma (look at the rose tea box in the images).
From the point of view of the "measurable" characteristics, then, the Canon is ahead, but if you ask me I'd say that
the Sigma, thanks to its better bokeh, can at times produce more pleasant images, though somewhat softer.
Probably the Sigma would fare forse coupled with a full-frame sensor, since the corner would be much weaker, but
that I don't know for sure, this is just a "projection".
Anyway, APS-C is my battleground, so if I had to pick one lens for indoor portraits, (do not forget these are
42mm-equivalent lenses, definitely short but useful if you don't have much room), the Sigma can be an option
if you are not a sharpness guy, but for most purposes I'd definitely pick the Canon.
Indeed, the street price of these legacy lenses reflects this difference.
To summarize, given their price, I can recommend any of the two if you like to use old lenses and you're not
scared by manual focus. Thumbs up!
Test images
A "reference" image taken with the Minolta MD 50mm f/1.4 at f/2.8. I like this lens, the bokeh is fine and the sharpness
is excellent. Rememeber though, you cannot compare apples to oranges, the 50mm has obvious advantages...
...in spite of all the praise, notice the green cast on the horizontal bands of the teapot in the background.
Now, at f/2.8, the Canon first, then the Sigma:
The images above tell something about sharpness but not much more; let's go a bit into details...
Let's give a look at sharpness in the centre. With the Canon I took the shots from a shorter distance, but
you can tell the difference anyway:
|
centre sharpness with the Canon FD 24mm at f/2.8 |
|
centre sharpness with the Sigma Super Wide 24mm at f/2.8 |
More interesting is the bokeh. Here the comparison that favours the Sigma... this is the only
area where it can obviously do better than the Canon:
bokeh of the Canon FD 24mm (f/2.8) |
bokeh of the Sigma 24mm (f/2.8) |
|
|
|
|
bokeh of the Canon FD 24mm (f/2.8) |
bokeh of the Sigma 24mm (f/2.8) |
In the background, the Canon has some nervousness while the Sigma is buttery, maybe you can't see the effect
in the whole image but on a larger monitor, or at 25-50% magnification, it is noticeable.
Looking at the second detail, I even have the impression that the Canon presents a very slight accent of "swirling".