The influence of the lens on the image result
Does the choice of lens have a greater impact on the image result than a few megapixels more or less?
This question arose after the extensive high-end camera test I conducted with my friend Christian Habermeier . Theoretically, it's clear that the choice of lens will have an impact. But how big is it? I wanted to explore this question, and fortunately, I was able to test five very different lenses in the 70/75 mm focal length range. Many thanks to Leica Camera AG Switzerland and Foto Vision Zumstein for loaning us the lenses, and also a big thank you to Iris Michel, Eva Küng, Simone Meylan, and Sam Bregenzer.
The 75mm focal length is very exciting in my opinion. A 75mm lens can be used both as a normal focal length and as a portrait focal length. This makes it very versatile. Thanks to the high resolutions of today's sensors, you can cover a wide range of subjects with a 28mm or even a 35mm lens and a 75mm lens, for example, because you can also "simulate" other focal lengths by cropping the image. Taking a 50mm crop from an image shot with a 35mm lens, or selecting a crop equivalent to a 90mm from an image shot with a 75mm lens, is easily possible with cameras with up to 50 megapixels.
The protagonists
I conducted the test with my Leica SL2, so all lenses can be attached to the L-mount directly or via adapter. Starting from left to right:
01 // Voigtländer 75 mm / 1:1.5 Nokton VM (aspherical)
Focal length: 75 mm
Overall length: 63.3 mm
Number of lenses: 7 lenses in 6 groups
Largest aperture: 1.5
Smallest aperture: 16
Closest focusing distance: 0.7 m
Filter diameter: 58 mm
Focus: manual
Weight: 350 g
Price: CHF 998
Special features: very attractive ratio of max. aperture / weight / price
02 // leica summarit-s 1:2.5/70 asph. (cs)
Focal length: 70 mm
Overall length: 93 mm
Number of lenses: 8 lenses in 6 groups
Largest aperture: 2.5
Smallest aperture: 22
Closest focusing distance: 0.5 m
Filter diameter: 82 mm
Focus: Autofocus
Weight: 740 g
Price: CHF 4640 (normal version) CHF 6030 (CS version with built-in shutter)
Special feature: the lens is designed for the (larger) Leica S-sensor and therefore has a larger image circle
03 // Sigma 70mm f2,8 DG Macro
Focal length: 70 mm
Overall length: 70.8 mm
Number of lenses: 13 lenses in 10 groups
Largest aperture: 2.8
Smallest aperture: 22
Closest focusing distance: 0.258 m
Filter diameter: 48 mm
Focus: Autofocus
Weight: 605 g
Price: CHF 648
Special: Macro
04 // Leica Noctilux-M 1:1.25 75 mm Asph
Focal length: 75 mm
Overall length: 91 mm
Number of lenses: 9 lenses in 6 groups
Largest aperture: 1.25
Smallest aperture: 22
Closest focusing distance: 0.85 m
Filter diameter: 67 mm
Focus: manual
Weight: 1055 g
Price: CHF 13,860
Special feature: fastest 75mm available
05 // Leica Apo-Summicron-SL 1:2/75 Asph
Focal length: 75 mm
Overall length: 102 mm
Number of lenses: 11 lenses in 9 groups
Largest aperture: 2.0
Smallest aperture: 22
Closest focusing distance: 0.5 m
Filter diameter: 67 mm
Focus: Autofocus
Weight: 720 g
Price: CHF 5350
Special features: Additional lenses with the same body and the same maximum aperture and characteristics are available (currently 28/35/50/75/90 mm, 21/24 mm in planning)
The Test Idea
As always with my tests, this time, too, the goal is to put the equipment to the test in practice. I have a few shoots scheduled for the test weekend: a portrait of a painter friend, a photo shoot with my friend Sam's 1969 Dodge Charger R/T 440 Magnum, and two more portrait shoots. In addition to the camera/lens combination I normally use, I'll be shooting a few images in which I'll be shooting a subject with all the test lenses. I didn't shoot any extreme backlighting situations or anything like that, but I think you can get a pretty good idea of the characteristics of the five lenses.
Before I get into the individual lenses, here are four test panels showing excerpts from the shots I took with all the lenses. I worked with the aperture fully open in three test situations. The maximum aperture varies, of course, but a fast speed is a key criterion when purchasing a lens. In my opinion, it wouldn't have made sense to have throttled down all these light giants to f/2.8. The outrageously expensive Noctilux, in particular, should and must be able to demonstrate its advantages:
Testtableau 1
Cockpit des Dodge Charger R/T 440 Magnum
All images are unedited
Testtableau 2
Feigenbaumblätter
All images are unedited
Test tableau 3
Eva
All images are unedited.
Testtableau 4
Iris
All images are unedited
Practical notes on the individual lenses
01 // Voigtländer 75 mm / 1:1.5 Nokton VM (aspherical)
I would have expected a lens with such a high speed to be larger and heavier. The Nokton weighs just 350g and is priced at a price you wouldn't expect. Personally, I think the lens offers extremely good value for just under 1,000 Swiss francs. Even at full aperture, the performance is very good. It produces images a little harder than the Leica Noctilux, but softer than the other lenses. This makes it an ideal portrait lens that, especially because of its small size, is easy to take with you. Precise manual focusing was a challenge for me. With the aperture fully open, I produced quite a lot of rejects. Some images weren't too off and could easily be published on all electronic channels (Facebook, Instagram, etc.), and many of them would also be suitable for A4 printing. But my goal is to make full use of a lens's sharpness, and my error rate is significantly higher with manually focused lenses than with AF models. Perhaps it's a matter of practice. I attach a processed image for each lens, because that's what you normally do with photos. You edit them before publishing or printing them. For the Nokton, I chose an image from the Iris series. With the aperture fully open, you get beautiful bokeh, and the slightly softer detail is perfect for the portrait of this amazing artist .
Edited image
Voigtländer 75 mm / 1:1.5 Nokton VM, 1/50 sec, f 1.5, 200 ISO, daylight
02 // leica summarit-s 1:2.5/70 asph. (cs)
I admit, the Summarit S 70mm is a bit of an oddity in this test series. It's designed for the larger sensor of the Leica S. However, based on my medium format test , I was very impressed by the combination of the S and the 70mm. So I couldn't resist and mounted an S 70mm with an adapter to my Leica SL2. And I wasn't disappointed. In my opinion, this lens has unobtrusive sharpness, not as "loud" as the SL 75 (more on that later), but still more accentuated than the Noctilux from the M series. And now comes the fascinating part: every photographer will develop their own style. Personal preferences and the subject matter will influence the choice of lens. However, in some cases, one lens can't cover everything, so you might want to "treat yourself" to two lenses of the same focal length to achieve, for example, a slightly softer or slightly harder rendering style. Or you can use a manually focused, wide-aperture lens plus an autofocus lens with a narrower aperture. And so on and so forth... For my style of photography, the Summarit S is the ideal portrait lens. A quick side note: On the Leica S3, the lens performs even better, and surfaces are rendered with even more nuance.
The image I chose for the Leica Summarit S is from the series I shot with Eva. She spontaneously started ruffling her hair, and she started laughing so hard from all the ruffling. And I was able to capture that exact moment. She has since posted the image on Instagram and Facebook and wrote to me that she's never received so many positive reactions to a photo of hers. I take that as a compliment ;-).
Edited image
Leica Summarit-S 1:2.5 / 70 ASPH / 1/100 sec, f 8.0, 200 ISO, flash
03 // Sigma 70mm f2,8 DG Macro
The Sigma lens is the cheapest in the test. So it's not surprising that its build quality isn't up to par with the other lenses. I bought it a while ago because the macro range of the L system is still somewhat dormant. And I have to say: Despite the low price, the Sigma delivers very good quality, and I can recommend it to anyone who needs a macro lens in the L system. At f/2.8, the aperture is the lowest in the test, but the Sigma makes up for it with its deep minimum focusing distance. A lens that delivers honest results at a very reasonable purchase price.
The image I chose as the edited photo for the Sigma lens is a still life from Iris' studio.
Edited image
Sigma 70mm F2.8 DC Macro, 1/80 sec, f 4.0, 200 ISO, daylight
04 // Leica Noctilux-M 1:1.25 75 mm Asph
The M-Noctilux is beyond all normal limits in some respects: Thanks to its maximum aperture of 1.25 (the fastest 75mm in the world), it offers the possibility of achieving the smallest depth of field. Despite this performance, it is incredibly compact. The incredible amount of power packed into such a small body becomes apparent when you pick up the lens: it weighs over a kilogram. Even at full aperture, the Noctilux delivers tremendous sharpness, which subjectively increases slightly when stopped down. It has an unobtrusive sharpness that can be further enhanced in post-production if necessary. For the edited image, I chose a photo of Sam's Dodge at the airport runway. Thanks to the full aperture, the classic car stands out beautifully from its surroundings. I selectively increased the sharpness in the area of the car a little. Under no circumstances should you focus across the entire image, as this would ruin the Noctilux's bokeh. The same applies to this lens: At full aperture, especially in portraits, despite focus peaking, I had a relatively high rate of inaccurate focus. These deviations are often in the millimeter range. For example, the tip of the model's eyelashes would be in focus instead of the eye.
Edited image
Leica Noctilux M 1:1.25 / 75 ASPH, 1/1000 sec, f 1.25, 50 ISO, daylight
05 // Leica Apo-Summicron-SL 1:2/75 Asph
The Leica SL prime lenses with an initial aperture of 2.0 have a very special look. I own the 35mm and 90mm and am a huge fan of these lenses. I don't know of any other lens in the 35mm format that delivers such sharpness in the focused range. It captures every tiny detail crisply and precisely. Out of focus, it's not quite as soft as, say, the Noctilux. This is likely due to its design and, of course, also because the initial aperture cannot be opened beyond 2.0. Leica deliberately dispensed with a larger aperture here in favor of compactness. However, because the Apo Summicron SL 75 makes such a crisp impression in the in-focus range, the difference between sharpness and blur is greater than you'd expect with an aperture of 2.0. For portrait shots where you don't necessarily need to see every detail, the Apo Summicron SL may not be the right choice. But when it comes to sharpness, this lens is in its element.
I deliberately chose a subject from my shoot with Simone as the edited image. We spontaneously did a bubble gum session with her Audrey Hepburn shirt. I think the harsh light from my Profoto B1 and the crystal-clear sharpness of the SL 75 work perfectly together. It's a rather "loud" lens, and that also fits the subject.
Edited image
Leica Apo-Summicron-SL 1:2 / 75 ASPH / 1/250 sec, f 10, flash
The big question about the resolution
I've pointed out several times that I miss information from the manufacturers regarding lens resolution. I know that Leica goes to great lengths to maximize resolution. About six years ago, Urs Tillmanns and I visited Leica headquarters in Wetzlar about this. The gist of our visit was – from my layman's perspective: The resolution of a lens is specified in line pairs per millimeter. This value obviously can't be simply converted 1:1 into megapixels, but one could certainly calculate an order of magnitude for how many megapixels a lens can resolve.
If every manufacturer were committed to specifying resolution in line pairs per millimeter, it might be easier to understand large price differences. After all, it's obviously nonsense to buy a 50-megapixel camera when the lens resolution is only 30 megapixels. Or conversely: If you shoot with a 24-megapixel camera and know you'll never need more resolution, you don't need to buy lenses with 50 megapixel resolution.
Conclusion
The lens has a significant influence on the image. If you know your lenses, you know how to use them, where their strengths and weaknesses lie. I know that Leica makes a lot of effort to ensure that lenses of different focal lengths are available with as similar image reproduction characteristics as possible. I assume that other manufacturers do the same. Once you have a series of lenses that all produce a similar image effect, you can work very well with them. My "work lenses" are clearly the SL prime lenses, with an emphasis on the two prime lenses of 35 and 90 mm. If your budget allows, you can certainly treat yourself to a lens with a different character and then use it consciously.
However, and this is both a disappointment and a comfort: even the best lens cannot turn a mediocre picture into a great photo.
;-)
