There are lots of things that can remedy higher f-stops to some extent, but nothing really substitutes that big aperature.
The big appeal if low f-stop lenses from high end lensmakers is that they have reduced aberrations/distortions because they use a shit ton of glass to improve the image, which in turn is why they can be so incredibly expensive. A $50 f/1.6 is going to be dogshit. The $5000 lens is going to have additional optics to remedy the large ROC and high-angle rays.
The trade-offs are often worth it.
Everywhere else, most lenses are sharped stopped down to the f/5.6–f/8 range, and depth-of-field is an entirely stylistic choice — e.g. shallow dof is popular with portraits, but largely undesirable for landscape photography.
That is no longer necessarily true. For example in Nikon world the current 70-200mm f4 is generally thought to have the same quality as the 70-200mm f2.8.
Lens quality in general has gone way up as digital cameras have exceeded the resolution of film. Now companies have to engineer even mid-range lenses to produce very high-quality images since even mid-range DSLRs might have 20MP sensors or more. And on a computer it's easy to zoom in and pixel-peep... and share your disappointment with everyone else if the lens is bad.
For all the legend-making around the Nikon 300mm f2.0, their latest 300mm f2.8 is going to outperform it in every way expect for the number of photons it lets through.
This is actually a funny thing. The APS-C Canon 90D has a slightly higher resolution sensor than the full frame 5Dmk4, and significantly higher than the brand new, also full frame, 1DXmk3. Sony’s APS-C bodies are all 24MP, the same as the a7iii and the flagship a9/a9ii.
Other than dedicated high-res models (5DS, a7R, D850/Z7), high-end cameras routinely have much lower pixel density than cheaper cameras, because resolution doesn’t matter that much for most applications, and pros care for a whole bunch of other features that scale poorly with resolution (such as low light performance and buffer drain speed)
Think of your classic Sports Illustrated photographer... those images are not going to run larger than double truck in a print magazine, and 12 MP is plenty for that. Heck, National Geographic's first digital two-page spread was shot with a Nikon D1X.
And news and sports images need to go out FAST... where again a lower MP count actually helps.
And at the same time it was just as likely to result in poorer pictures because of focus shift when stopped down.
Meh, they use a shit ton of glass _which introduces aberrations_ which needs more glass to correct.
I bought a 50mm 1.2 ai-s, and sent it back a few days later. The dof is unusable at f1.2 and after f2.8 it looks like any other quality 50mm lens. It vignets like crazy and edges aren't sharp until you stop down to regular apertures. So yeah sure you can shoot a bit better in low light, if you like blurry and soft pics.
> The trade-offs are often worth it.
For pros, maybe, for prosumers and consumers I highly doubt it.
40 years old actually, still made new by nikon in their japanese factories to this day.
> Canon RF 50mm f/1.2
I'd happily test one but it costs more than my whole 35mm + medium format setups + darkroom equipment. It weights 3 times more than the nikkor and uses 77mm filter instead of 52mm so this is already a big no-no in my books.
I'm sure there are good fast lenses, it's just that they have so many drawbacks that it doesn't make sense for the vast majority of photographers.
http://www.photosynthesis.co.nz/nikon/lenses.html
>I'm sure there are good fast lenses, it's just that they have so many drawbacks that it doesn't make sense for the vast majority of photographers.
My point was its not fair to use an old obsolete lens to denounce fast aperture primes of today.
This isn't about getting the best image possible but about capturing something you otherwise couldn't get at all.
All of this gear is about flexibility to handle poor lighting conditions, things moving quickly, etc. If you are product photographer with a room full of lighting equipment you are going to pick the right lens for the job and make the room work. Other people rarely have this freedom.
It's worth noting that in the last couple of generations of digital sensors, we're objectively in a better situation than fast film was, so that loosens the need for fast glass a bit. The same is true for widely deployed mostly ok physical image stabilization systems.
At the end they compare budget lenses like the Canon 50mm f/0.95 and find that the SLR Magic 25mm T0.95, seems to work better in low light.