Chicago Skyline

[Brainonska511]

I took this the other night: https://webshare.uchicago.edu/...an/Public/Desktop5.jpg
Any tips on how to get sharper night photos with maybe less noise?

It was shot at:

F13, 20 second exposure, ISO 100 on my Rebel XT with a Tamron 28-75 f/2.8 lens

 

[OdiN]

Looks like it was kind of a hazy night, so that didn't help.

Try f/8 or so could help. Higher ISO and a shorter exposure could also help. ISO 400 won't introduce much noise, whereas a longer exposure would probably introduce more than a shorter one at higher ISO.

 

[alfa147x]

Originally posted by: OdiN
Looks like it was kind of a hazy night, so that didn't help.

Try f/8 or so could help. Higher ISO and a shorter exposure could also help. ISO 400 won't introduce much noise, whereas a longer exposure would probably introduce more than a shorter one at higher ISO.

so wait
Lower(100 - 200) iso + slow shutter speed != low noise
but
High (300 - 500) iso + slow shutter speed = low noise ?

 

[OdiN]

No....any time you use a long shutter speed you will introduce noise. That's why cameras are putting in long exposure noise reduction. It doesn't matter what ISO you're at, a long exposure will generate more noise than a shorter exposure. With a lower ISO you have to have a longer shutter speed than a higher ISO. Even though higher ISO's produce more noise, if you open up the aperture and use a higher ISO you are able to use faster shutter speeds than a low ISO and smaller aperture. The noise from the longer exposure will often outweigh the noise of a higher ISO but faster shutter speed.

As you leave your sensor powered longer, you're going to introduce noise - you will notice hot pixels, etc. which are not normally visible during faster shutter speeds.

Does this make sense?

This is just a suggestion as you may find different cameras produce different results from something like this. You would need to test it but I'm just offering it as a possible way to help improve the shot.

 

[fuzzybabybunny]

The f/13 is what's killing you, plus maybe some haze. f/8, ISO 100, good tripod and mirror lock up, and you should be good to go.

At least on my Canons I haven't noticed any noise as a result of long exposures. Then again I've never actually compared a long exposure low ISO with a shorter exposure higher ISO shot. The low ISO shot has always been pretty much noise free for me.

 

[Brainonska511]

Thanks for the tips. It was a little hazy out over the city. I'll try going up to the top of that parking garage another night and see if I can get some better results.

 

[Alyx]

I don't think 20 seconds will introduce much noise. Also for your sensor size don't go above f/11. You start to loose sharpness once you go above that due to diffraction.

http://www.cambridgeincolour.c...action-photography.htm

 

[Brainonska511]

Originally posted by: Alyx
I don't think 20 seconds will introduce much noise. Also for your sensor size don't go above f/11. You start to loose sharpness once you go above that due to diffraction.

http://www.cambridgeincolour.c...action-photography.htm

Hm... I never thought about that either.

 

[dblevitan]

20 seconds you should be fine with. I would say stick with lower ISOs and longer exposures rather than higher ISOs and shorter exposures (as long as you're using a tripod and the exposure isn't beyond a minute or two). However, make sure the camera does the long exposure noise reduction. This essentially takes another exposure of the same length but with the shutter closed to create a "dark frame" (at least that's what Nikons do). The camera will then subtract the dark frame from the original image which usually removes quite a bit of noise since the noise is a result of the sensor being on. This is a standard process in astronomy, where exposures are often longer than a few minutes, and usually removes a good deal of noise.