Considering a still life, so with no mobile subjects.

When making long exposures the noise tends to increase.
When using higher ISO the noise tends to increase too.

The question: is it better to increase the exposure time or the ISO value?

concretely:
40 sec> 100 ISO
10 sec> 400 ISO
05 sec> 800 ISO

What will give the best result?
Or the results will be identical?

I would say exposure time once the light coming in isn't artificial like the ISO is

40 sec> 100 ISO  would give the best result IMO

You didn't mentioned what camera you have. Modern DSLRs are amazing at 800ISO, so I would choose 5sec/800ISO combination with newer cam.

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Yes, it could be the solution, if I could have the possibility to try (and the time)
Then I should have the possibility to check the result on a good monitor.


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Come on, you just need 55 sec for that!

Hi Beppe,

I just went out last weekend and did some slow shutter speed shooting down at a local pier.  I used the lowest possible ISO (100) and very long shutter speeds.  Here are a couple of examples.  These were done at 4:30 - 5:00 am with no (or a very, very slight hint that the sun is coming up - which gave me the blue sky with a 270 second exposure.  I know you were looking at shorter shutter speeds but I am posting because as long as your histogram is spot on, noise is almost non-existent.  I am shooting with a Nikon D7100 24 mp.  As I mentioned, the key is to get the exposure nailed using your histogram and only conduct minimal post processing (unless you are going to significantly downsize). These images required very little post processing.  I was light painting.

The shot of the pier (full shot) was at 7am using a big stopper 10x ND filter and that shot, too, had no noise, but the ones where my histogram was off (under exposed) got all noisy when I tweaked them in Photoshop, so I scrapped them.  A major key to noise reduction is proper exposure.

To do your own experiment, you just have to take two consecutive photos and change the settings between each exposure. I think that would be far more valuable than what other people might think. A lot of 'information' passed around is speculation, and even if based on experimentation, if they weren't using your set-up (particularly camera) their results might not correspond with yours.
Think yourself lucky you have a choice, in that your subject isn't moving!

Right top corner is worst, the other three are similar.

Right top corner is worst, the other three are similar.

The one in the bottom right corner is the same than the one in the top right corner but with a very higher value of denoise in Lightroom. I don't think that it is a good solution.

The good solution is low ISO + long exposure, as you have previously said.
But I am surprised that there is a so huge difference between 100 and 800 with the D610 which is known to be a very good camera when used with high ISO

Quote from: Ron on May 15, 2014, 09:59

Right top corner is worst, the other three are similar.

The one in the bottom right corner is the same than the one in the top right corner but with a very higher value of denoise in Lightroom. I don't think that it is a good solution.

The good solution is low ISO + long exposure, as you have previously said.
But I am surprised that there is a so huge difference between 100 and 800 with the D610 which is known to be a very good camera when used with high ISO

There is some low-frequency chromatic noise in the background of the bottom right - presumably put there by Lightroom as it tried to even everything out.

It looks like you had sharpening up to 50 - that's very high and could account for the noise. Sharpening at 50 seems really high - with a subject like yours, there should only be a need for very minimal sharpening, IMHO.

Noise can also be affected by which camera profile you use. I shoot with a Nikon D700 and a D5100 and find that particularly where a subject has a lot of shadows or my light wasn't optimum, using "Camera Neutral" will give me the lightest image since any increase in exposure or shadows done in LR will increase the possibility of creating noise. You can then tweak the contrast and saturation slowly to see how it affects the image.

Even though newer cameras are quite good at high ISOs, if you're shooting an image with large areas of solid color, using a lower ISO will generally give you a cleaner image, but this will change as the camera gets hotter and long exposures do increase the noise. Best idea is to bracket and see which gives you the best shot.

It looks like you had sharpening up to 50 - that's very high and could account for the noise. Sharpening at 50 seems really high - with a subject like yours, there should only be a need for very minimal sharpening, IMHO.

Noise can also be affected by which camera profile you use. I shoot with a Nikon D700 and a D5100 and find that particularly where a subject has a lot of shadows or my light wasn't optimum, using "Camera Neutral" will give me the lightest image since any increase in exposure or shadows done in LR will increase the possibility of creating noise. You can then tweak the contrast and saturation slowly to see how it affects the image.

Even though newer cameras are quite good at high ISOs, if you're shooting an image with large areas of solid color, using a lower ISO will generally give you a cleaner image, but this will change as the camera gets hotter and long exposures do increase the noise. Best idea is to bracket and see which gives you the best shot.

If you're shooting raw, it doesn't matter what profile you use except for how you want the image to look on the screen on the back of your camera. If you want the camera to record as much information as possible in the shadows and highlights, and keep it saved for you, you should shoot raw anyway.

I was talking about the profile used in LR - since, when you shoot in RAW you can change it afterwards. I know it really doesn't matter the in camera settings unless you're shooting jpegs.