Do lenses have an effect on noise?

W44NNE

W44NNE

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Last night, I had to photograph an event we went to in the dark. It started at around 7PM so the sky was pitch black. I needed a wide angle and the only lens I had for this, offers a lowest stop of 3.5. I was shooting hand held and only had to ditch around 3 out of 600 or so photos, which is obviously fine. My issue therefore wasn't with blurring, but noise. I had to shoot at higher ISOs ranging from around 800 to 3200 on my Nikon D610.

Noise has become present when editing the photos as I'd expect. It's not terrible but I wondered how a different lens may have made a difference here? For example, lifting the shadows in lightroom, creates colour noise against the pitch black sky.

Perhaps if I'd been able to make do with my 50mm f1.8, would using it at this lower stop still have given me decent depth of field in this circumstance? Or would it have still performed better when stopped down to 3.5+ as with the lens I took?
 
The noise is caused by the higher ISO used, which presumably you needed in order to get an exposure at a reasonable shutter speed. To get less noise you'd need a lower ISO which means either a slower shutter speed (tripod or image stabilisation) , a lens with a larger aperture (used at its widest aperture) or more light. Using a faster lens stopped down would create the same noise as your f/3.5 lens (or even worse with a 50mm lens as you'd need an even higher ISO setting to get a usable shutter speed).
 
Noise can be a result of under exposure but you will notice some noise at 3200 on full frame especially if under exposed.
 
Thanks, that helps to clear things up. I needed the faster shutter speeds as there was so much movement... generally very pleased with the photos but I wondered how I could improve noise for the future.
 
W44NNE said:
Thanks, that helps to clear things up. I needed the faster shutter speeds as there was so much movement... generally very pleased with the photos but I wondered how I could improve noise for the future.
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Don't be tempted to under-expose and then try to restore correct brightness in post processing. You will always get a better result by pushing the ISO at the shooting stage and letting the camera's A-D converter do that.

I suspect most of the problem here though is too much use of the shadows slider in Lightroom (which is so tempting ;)). What you are effectively doing there is pushing the ISO in darker areas, often quite a lot, and again it's better to raise the ISO at the taking stage if minimal noise is priority (and then darken the highlights in PP if necessary, providing they're not blown).

It's a tricky balance and often necessary to accept a few compromises at say an event where there is a lot of blackness and dark shadows combined with bright stage lights. In a nutshell, enable blinkies so you know when highlights are blowing (you'll quite likely have to let some of them blow, providing they're not too important) then push the ISO to get a bit of shadow detail.
 
a 1.4 lens would mean you could of gotten away with a upper limit of 400-640 iso i think.
some lenses have a higher T stop (transmition level) than others, so the light getting to the sensor can be less than the f stop of the lens.
cinema lenses are marked in t stops
 
Also be away that at those iso settings the only people who're going to care about the noise are other photographers. The clients who order prints will most likely not even notice it.
 
As always, there are 3 corners to the exposure triangle, shutter speed, aperture and ISO. Since you're after a fairly narrow aperture to get sufficient DoF and a fast enough shutter speed to reduce or eliminate movement, you'll have to raise the ISO to get the correct exposure. Not sure how high the D600 can go before noise starts to become obtrusive but I'd guess at 1600 or so. Even above that, you'll probably be able to get images cleaner by using some NR software in PP - there are plenty of software options, some even free! Oh, to answer the original question, a lens shouldn't have any influence on noise (apart from actual sound - some older [screw driven] lenses are louder than modern AF-S ones.) at the same aperture, all a faster lens can do is allow a lower ISO to be used.
 
If the output is smallish - i.e. typical print sizes then that will also have the effect of reducing any visible noise. I've found that it is important to get the exposure correct at higher iso's (well it's important always but you get the idea ...) as lifting an underexposed image will introduce more noise. When shooting at high iso values then using the ETTR method gives me the best results http://www.luminous-landscape.com/tutorials/expose-right.shtml
 
PaulButler said:
If the output is smallish - i.e. typical print sizes then that will also have the effect of reducing any visible noise. I've found that it is important to get the exposure correct at higher iso's (well it's important always but you get the idea ...) as lifting an underexposed image will introduce more noise. When shooting at high iso values then using the ETTR method gives me the best results http://www.luminous-landscape.com/tutorials/expose-right.shtml
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Yep, that's what Hoppy was alluding to. :)
 
If you shoot over exposed and then try and recover it will you get the same thing happen with noise ?
 
Lenses themselves do not add or remove noise, no... but a faster lens will allow you to use a lower ISO at the same shutter speed.... so in a way, yes, they do. If I have a lens with a maximum aperture of f5.6 and I need 1/60th @ ISO3200, then a f2.8 lens would have allowed me 1/60th @ ISO 800 (as it's 2 stops faster)... so the results would contain less noise.
 
Davemm said:
If you shoot over exposed and then try and recover it will you get the same thing happen with noise ?
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No, because the majority of noise is in the shadows and ETTR allows you to keep more detail in the shadows. It's a fine line and you have to practice and shoot raw, but there is enough detail in the highlights to recover.
 
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