Testing: Longitudinal Chromatic Aberration and focus shift
Even though Sony’s super-zoom starts with a focal ratio of only f3.5 it shows some longitudinal color aberrations (loCA, a.k.a. “axial color” or “bokeh CA”): The foreground shows a light magenta coloration and the background a light green color shift. loCA are not easily corrected in post-processing.
The other thing of note is a strong focus shift towards the foreground: This makes the numbers on the right side in the background less sharp when the lens is stopped down. This happens even between f5.6 and f8.0 where depth of field should cover such an effect. I’ve never seen such a strong effect on a lens before and I’d recommend to re-focus the Sony every time you change aperture.
The following real life shot shows that the Sony FE 24-240mm f3.5-6.3 OSS produces only little purple fringing around high-contrast edges in the focal plane but a bit of green outlining around background subjects:
Sharpness and contrast
Let’s have a look at the theoretical performance of the Sony FE 24-240mm f3.5-6.3 OSS first and compare it to the performance of the Tamron 28-200mm f2.8-5.6 Di III:
Above: Sony FE 24-240mm f3.5-6.3 OSS, 24mm f3.5 (left), 240mm f6.3 (right)
Above: Tamron 28-200mm f2.8-5.6 Di III, 28mm f2.8 (left), 200mm f5.6 (right)
These MTF charts show the computed lens-performance of lenses wide open without influence of diffraction. Higher values are better (more contrast) and the closer the line-pairs are together the less astigmatism (= resolution depends on the orientation of the test-pattern) the lens has. The x-axis displays the distance from the optical axis (=center of the sensor) in mm. I’ll show you the real-life performance at 4 mm (center), 13 mm (APS-C-corner), and 20 mm (FF-corner) on a on a 42MP Sony A7R II camera.
Contrast and resolution: Comparing the MTF charts of both lenses is a bit tricky as Sony crammed both the wide open performance (green lines) and performance at f8.0 (red lines) into the same chart. Looking closely the Tamron shows less astigmatism on the wide end than the Sony with comparable overall contrast and better resolution towards the full-frame corner. At the long end the Tamron also shows some astigmatism but not nearly as much as the Sony and again the Tamron should be a bit sharper.
Let’s see how this theoretical performance translates into real life results in the sharpness test based on Siemens-stars. Processing was done in Lightroom 9.3/CRAW 12.3 from RAW to Adobe Color profile with the built-in lens profile for Vignette Control and CA compensation applied. I also activated Adobe’s lens profile for distortion compensation. Noise-reduction is set to 0, sharpening to 50/0.5/36/10, with no extra tone, color, or saturation adjustment. White-balance was adjusted to a neutral white and I did some exposure compensation to make the brightness of all crops match. So you will not see light fall-off in the corners.
The following are all 100% crops!
First up is an overview of the wide-open performance at different focal lengths. You can jump to the detailed results at different apertures and comparisons with the Tamron 28-200mm f2.8-5.6 Di III by clicking on the crops of the respective focal length.
Sony’s super-zoom lens starts a bit soft at 24mm focal length but produces a sharp to very sharp APS-C image-circle between 28mm and 70mm. Then it becomes progressively softer even in the center especially at 150mm and 200mm focal length. At 240mm sharpness recovers a bit. The FF-corner is soft but usable up to 105mm focal length with best performance between 35mm and 70mm. At 150mm and beyond it still shows some detail but with a haze from astigmatism and residual spherical aberrations lowering contrast considerably. The lens exhibits a bit of field curvature but nothing worrisome.
If you want to see all the details, read on. Or you can fast-forward to the performance at long distances.
The following 100% crops for each focal length show the Sony FE 24-240mm f3.5-6.3 OSS from wide open down to f11 compared to the Tamron 28-200mm f2.8-5.6 Di III. When shooting the Sony I refocused for each aperture down to f8.0 to avoid the softening effect of focus shift.
Performance at 24mm:
Stopping down to f5.6 helps the APS-C-corner but the FF-corner stays soft.
Performance at 28mm:
At 28mm focal length the Tamron 28-200mm is clearly sharper than the Sony – even when the Sony is stopped down to f5.6.
Performance at 35mm:
At 35mm focal length the Sony and Tamron look very similar in the APS-C image-circle with the Tamron being slightly sharper in the center – and much sharper at the FF-corner. Stopping the Sony down to f5.6 lifts its FF-corner to good resolution although it is still softer than the Tamron at f4.0.
Performance at 50mm:
Similar picture like at 35mm.
Performance at 70mm:
At 70mm focal length the Sony is only slightly behind the Tamron 28-200mm.
Performance at 105mm:
At 105mm focal length the Sony starts to soften and now falls clearly behind the Tamron 28-200mm. Stopping the Sony down to f8.0 closes the gap.
Performance at 150mm:
At 150mm focal length the Sony is now becoming very soft and should be stopped down to f8.0 or even f11 for better resolution.
Performance at 200mm:
Similar picture as at 150mm.
Performance at 240mm:
At 240mm focal length the Sony FE 24-240mm f3.5-6.3 OSS is a little better than at 150mm and 200mm.
In this comparison Sony’s FE 24-240mm f3.5-6.3 OSS zoom lens is clearly out-performed by the Tamron 28-200mm.
Performance at long distances
The Siemens-star test-targets are shot at a distance of 45x focal length (i.e. at around 3m for 70mm focal length). But performance of lenses also depends on the shooting distance. Therefore I present another series of test-shots of a city around 1 km away. Processing was done in Lightroom 9.3/CRAW 12.3 from RAW to Adobe Color profile with the built-in lens profile for Vignette Control and CA compensation applied. I also activated Adobe’s lens profile for distortion compensation. Noise-reduction is set to 0, sharpening to 50/0.5/36/10, with no extra tone, color, or saturation adjustment. When shooting the Sony I refocused for each aperture down to f8.0 to avoid the softening effect of focus shift. All shots were made at ISO 100 and image stabilization switched off.
Following is an overview of the wide-open performance at different focal lengths. You can jump to the detailed results at different apertures and comparisons with the Tamron 28-200mm f2.8-5.6 Di III by clicking on the crops of the respective focal length. As usual I have selected the diagonal that provided the better corner results as almost any lens is a bit decentered.
At long-distances Sony’s super-zoom lens does not look much different from the first test: it starts a bit soft at 24mm, has good sharpness in the APS-C image-circle between 28mm and 70mm, and becomes progressively softer towards the long end. The FF-corner looks best at 50mm and worst at 24mm and 240mm. But it still shows enough detail to be usable.
The following images show the complete scene wide open to give you an impression of the angle of view and to judge vignetting. Following the main image are 100% crops from the center, APS-C-corner, and FF-corner for each focal length from the Sony FE 24-240mm f3.5-6.3 OSS down to f11. For comparison I use the Tamron 28-200mm f2.8-5.6 Di III shot only minutes apart.
You can access the large originals but please respect our copyright and only use those images for personal use.
If you don’t want to see all the details and comparisons fast-forward to the next chapter on vignetting and distortions.
Results at 24mm:
Stopping down to f5.6 makes the APS-C-corner more well-defined and also cleans the FF-corner a bit.
Results at 28mm:
At 28mm focal length the Tamron is clearly sharper than the Sony across the full-frame sensor.
Results at 35mm:
Same story as at 28mm.
Results at 50mm:
At 50mm the Sony seem to have sharpened up a bit and is almost indistinguishable in the APS-C image-circle from the Tamron – which still has the sharper FF-corner.
Results at 70mm:
Same story as at 50mm.
Results at 105mm:
At 105mm the Sony starts softening outside the center and becomes visibly softer than the Tamron.
Results at 150mm:
Same story as at 105mm with the center of the Sony now also becoming softer.
Results at 200mm:
The Tamron (again) is the clear winner at 200mm.
Results at 240mm:
At 240mm focal length the Sony FE 24-240mm f3.5-6.3 OSS looks a bit sharper in the APS-C image-circle than at 200mm.
In this long-distance test the Sony FE 24-240mm f3.5-6.3 OSS showed very usable results but it was consistently out-performed by Tamron’s new 28-200mm f2.8-5.6 Di III.
Vignetting and distortions
To make it easier to see light fall-off in the corners of a full-frame sensor I’ve arranged a series of three shots each with the Sony FE 24-240mm f3.5-6.3 OSS from f3.5 to f8.0 at 24mm and f6-3-f11 at 240mm focal length. All images were developed to the same brightness in the center and with the built-in lens profile for Vignette Control and CA compensation applied. I also activated Adobe’s lens profile for distortion compensation as this is essential to get rid of extreme vignetting at 24mm:
The sample images above show that even with the lens profile applied vignetting is not completely eliminated. But on the long end it’s pretty inconspicuous. At 24mm f3.5 automatic shading compensation lifts the extreme corners about 0.8 EV. Adobe’s RAW converter automatically applies shading compensation as it was set in camera – but you cannot alter the setting in postprocessing.
Distortions are of a heavy barrel type at 24mm focal length and show the shadow of the rear frame of the lens if not corrected. They turn to noticeable pin-cushion at 70mm (see below). The setting for distortion compensation in camera is currently ignored by Adobe’s RAW converter and treated as OFF. So you have to manually activate Adobe’s lens profile for the Sony FE 24-240mm f3.5-6.3 OSS. Just make sure when you activate the Adobe lens profile to reduce its vignetting compensation as this is added on top of the already applied shading compensation and leads to artificially bright corners. This is all pretty confusing and I can only hope that one day Adobe and the lens/camera makers can agree upon which part of the lens profile is automatically applied in RAW development and which part has to be activated manually in post-processing. But Adobe’s lens profile at least does a pretty good job to correct for distortions – as does the distortion compensation in camera when you shoot JPGs:
Rendering of point-light sources at night-shots
Night-shots pose a different challenge for lenses as the contrast is even higher than under bright sun and point-light sources can reveal some weaknesses such as coma, haloing and colour-aberrations that do not show up as prominently in other test-shots. The 100% crops below the main image show the effects at the center and in the FF-corner of the Sony FE 24-240mm f3.5-6.3 OSS compared to the Tamron 28-200mm f2.8-5.6 Di III:
The Sony shows some coma in the corner – but less than the Tamron which is at f2.8 here. Coloration around point-light sources in the center is minimal.
Rendering of out-of-focus point-light sources
This test is for the rendering of point-light sources in an out-of-focus background. The circle of confusion that is produced by this test is pretty indicative of Bokeh performance (in the background) and light fall-off. Ideally the out-of-focus image of the point-light is evenly lit and perfectly circular, with no “onion-rings”, and without coloration. There’s also an effect known as “cat’s eye” the further away from the optical axis the point-light is projected. This is due to optical vignetting in the lens barrel when light enters the lens from an angle.
All images were shot at the longest focal length and largest aperture. The Sony FE 24-240mm f3.5-6.3 OSS is first followed by the Tamron 28-200mm f2.8-5.6 Di III. Crops are from the center, APS-C-corner, and FF-corner resized to make them comparable across all my reviews.
The Sony shows stronger onion rings in the center than the Tamron. Some outlining is visible on both lenses but there is very little coloration. Looking towards the corners both lenses develop a similar degree of cat’s eye effect in the FF-corner but compression is quite visible already at the APS-C-corner.
Now let’s see how this analysis of out-of-focus point-light sources translates into Bokeh-performance shooting a book-shelf. Crops are from the foreground, middle-ground, and background resized to make them comparable across all my reviews. I used the longest focal length that I could to produce a comparable shot to my other reviews which was in the case of the Sony 172mm. The other lenses had to be zoomed in to 162-172mm to achieve the same magnification from the same distance:
As was to be expected from the night shots both super-zooms have a pretty similar background Bokeh due to the aperture being at f6.3 resp. f5.6 already. Looking closer the Sony is a tad more nervous than the Tamron. The real eye-opener in this comparison are the last crops from the Tamron 70-180mm f2.8 Di III at 165mm f2.8: It clearly shows how much more blur you can produce with a larger aperture lens.
The Sony goes down to 1:3.6 magnification at 240mm focal length. The following images were shot at 1:3.7 magnification where the area of sharp focus is just 133 x 89mm. The crops shown below are from 0mm, 12mm, and 18mm off the center of the sensor respectively:
The Sony FE 24-240mm f3.5-6.3 OSS produces good results in the center but the outer crops are clearly softer and stay so even when stopped down.
Flare, ghosting, and sun-stars
Catching a strong light-source shining directly into the lens is always a risky business: it could produce strange colorful ghost-images or reduce contrast considerably through flare and glare. The appearance of flare and ghosting depends on factors like the aperture and the angle of the light hitting the lens. So to judge the proclivity of the Sony FE 24-240mm f3.5-6.3 OSS for these artifacts I went through a series of well calculated shots against a strong light source to provoke glare and ghosting.
The Sony FE 24-240mm f3.5-6.3 OSS produces some ghosting artifacts at the short end but outside these artefacts overall contrast stays pretty good with little veiling glare. Zooming in toward the long end veiling glare can reduce overall contrast considerably. And if the light-source is close to the FF-corner it can produce a strong flare there:
The little bright square inset in the upper left of both images shows the respective area with an exposure compensation of +3 EV to make it easier to see which levels of black the lens renders at that point. What you can also see in the images above: The Sony super-zoom does not produce well defined sunstars at f11.
Next check out my sample images!Check prices on the Sony FE 24-240mm f3.5-6.3 at Amazon, B&H, Adorama or WEX! Alternatively get yourself a copy of my In Camera book or treat me to a coffee! Thanks!