In low light shooting are fast lenses really needed?

When looking for a prime lens for low light shooting, are very fast lenses needed?

In my case a prime for night street scenes or museums with subdued lighting. I've been looking at primes
at f1.2, f1.4, f1.7, f1.8. But with today's cameras having great IQ at high ISO and image stabilization, are
fast lenses as these really needed? I read a comment that one doesn't need a lens faster than f2.8 for low
light conditions.

Me thinks these fast lenses are mostly to provide shallow DOF, subject isolation, and more for artistic purposes.

Comments?

yes. Sure you can get ok shots, but better with faster lens if you can get close enough to the action. These are at high ISO....

Mike.


This was shot at 600 mm, f6.3, 1/500 ISO 2560, Sigma 150-600, Canon EOS 1Dx under lights at night.

IMAGE LINK: https://photos.smugmug​.com …/AC3P2957-X2.jpg&lb=1&s=A

IMAGE LINK: https://photos.smugmug​.com …/AC3P1794-XL.jpg&lb=1&s=A

Different kind of lens and shooting conditions than I was discussing.
But good point about the high ISO.

I started shooting way back in the days of film, and ISO 400 was the highest rated film in 135 format.
As the photograpy editor of my high school newspaper, I found myself limited to 1/15 f/2...slower shutter not possible, faster aperture not possible for my equipment.

Take that as a starting point and if I could afford f/1.4 as a teen, it is only gaining ability to shoot in -1EV dimmer light.

But with today's digital high ISO hitting ISO 102400 in the Canon R6, that is almost -8EV dimmer light than what I could use with my f/2 lens. I could use f/4 with shutter 1/1000 instead! No, the fastest aperture is no longer necessary...I am content to have f/2.8 be my fastest aperture lens today. In the earlier days of digital and ISO 1600 at the top, with the Canon 20D, I would mount f/2 lenses from film cameras to help in low light conditions. No more.

Perfectly Frank wrote in post #19297981
When looking for a prime lens for low light shooting, are very fast lenses needed? ...
Comments?

Not these days or ever depending on what your shooting. You have three variables to control, speed, aperture, and ISO. For example, where speed is not a factor, you can slow the shutter down to seconds or minutes if needed allowing you to adjust the other variables to your liking. Your example of night street scene would probably fall into this unless your looking at the people on the street. But these days with cameras supporting unheard of ISO, you have a lot more flexibility.

Those f/1.8 and faster lenses were designed in the olden days when Kodachrome had an ISO of 25 (!).

Folks held the fast lenses in awe because they solved the problem of slow film and because they were expensive. And they were beautiful to behold.

Today we still hold them in awe, because photographers tend to be traditionalists. I still have my Pentax Takumar SMC 50mm f/1.4, made with thorium glass.

There may still be some use for those fast lenses, but for the most part, we don't need them. In fact the trend is going in the opposite direction, with lenses like Canon's RF 800mm f/11, which was mocked initially but has turned out to be very useful. There is also the slow RF 100-400 zoom.

Thanks for the opinions. I recently bought a used Olympus E-5M III.
Intended as a walk-about camera, I may use it in museums with dim light.
Olympus cameras are not the first choice for high ISO shots, so I considered
a fast prime. The Oly 17 f1.2 and 17 f1.8 and Pany 12 f1.4 were on my list.

They gather lots of light, but their DOF is shallow, perhaps too shallow.
I could stop down to get more DOF, but that defeats the light gathering
ability of the lens. They are expensive, too.

I also bought a used Oly 12-40 f2.8. I'll give it try for low light shooting,
and put the fast primes on the back-burner for now. Noise in Oly raw files
cleans up nicely with DXO. Also, the E-M5 III has IBIS rated at 5.5 stops,
which should allow me to hand hold at slow shutters speeds.

If Oly doesn't work in low-light, I'll grab my 6D.

No, fast lenses aren't really needed because of low light these days.

Nowadays, high ISO performance has evolved to the point that the vast majority of photographers can get enough shutter speed for the vast majority of their shooting, even with relatively slow lenses.

Fast lenses with large maximum apertures are all about depth of field control, and not really about low light anymore. Things have changed a lot in the past 10 or 15 years.

In my prior post, I mentioned -8EV dimmer light capability on the R6, compared to what I shot at ISO 400 while in high school.

Your Olympus has ISO range only -6EV dimmer than what I shot at ISO 400 while in high school...so f/4 at 1/250 with your Olympus, rather than f/4 at 1/1000 with the R6.
Less capable, yes, but sufficient to not worry about motion blur if folks are not making really fast gestures!

I like this....LOL.....(renta​l) 300mm f2.8 prime. But missed the game last night.

I know the images are a bit 'noisy' but are acceptable to me at the distance I was shooting at (from the stands).

The key for me is the speed of focus. With a slower lens the camera will focus accordingly.
At higher fStops the number of focus points decrease which the camera can effectively use.

When I was in high school ASA 1600 film was the fastest Black and White film I would use and it was pretty grainy, the 'noisy' digital photos at 256000 ISO are much better! When I did my own color processing I used 400 occasionally but preferred shooting everything with ASA 100 film. I think I shot slides ONCE. ASA 64.

I've been pretty happy shooting at f5.6 (extender on 70-200) but playing with the big boy lenses for fun. I got to rent that 200-400 L gofundmepage opened.

Mike

Wilt wrote in post #19298298

Perfectly Frank wrote:
I recently bought a used Olympus E-5M III.
Intended as a walk-about camera, I may use it in museums with dim light.
Olympus cameras are not the first choice for high ISO shots, so I considered
a fast prime.

In my prior post, I mentioned -8EV dimmer light capability on the R6, compared to what I shot at ISO 400 while in high school.

Your Olympus has ISO range only -6EV dimmer than what I shot at ISO 400 while in high school...so f/4 at 1/250 with your Olympus, rather than f/4 at 1/1000 with the R6.
Less capable, yes, but sufficient to not worry about motion blur if folks are not making really fast gestures!

Yes, good points.
And the camera's 5.5 stops of IBIS should help too. If combined with a lens that has IS, then 6.5 stops can be achieved.

Perfectly Frank wrote in post #19298328
Yes, good points.
And the camera's 5.5 stops of IBIS should help too. If combined with a lens that has IS, then 6.5 stops can be achieved.

While IBIS helps with photographer shake, IBIS does nothing for subject motion.

One thing to think about is that with the very fast lenses, you still have the option to stop down a bit for the DoF, and that will usually bring you a little advantage resolution wise, since most lenses seem to perform best a stop or so down from maximum. So maybe a 50mm ƒ/1.4 will give a better result shot at ƒ/2.8 than an ƒ/2.8 zoom shot at the same focal length?

Alan

If we're talking zooms, I've also found a bigger factor could be focal length. I have found that the cheaper super zooms can get softer at the longest focal lengths. Before I invested in better quality lenses, I had a Tamron 70-300mm Di VC. It was very good in the 70-200 range. When you got to 300mm, there was a noticeable softness at any aperture.