Hot!What is ISO and Noise?

Author
Poseidon
  • Total Posts : 307
  • Scores: 2
  • Reward points : 241
  • Joined:
  • Location: Swartz Creek, MI
  • Status: offline
0

What is ISO and Noise?

I guess I am in a mood to do demo's today!

ISO settings are simply a measurement of how sensitive your sensor (or film) is to light. The HIGHER the setting the more sensitive your sensor is, but at a cost of grain or noise, especially in the shadow areas. If you set a lower ISO, then you will have less noise, but you will need a larger aperture, or a longer shutter speed.

There are times where you HAVE to set a very high ISO in order to get a useable picture. Examples may be things like high school gyms, wedding ceremonies (where flash is not allowed), or even in your living room. However as a general rule, you will want to select the lowest possible shutter speed that provides you a useable shutter speed.

Getting back to Reef tank photography, depending on the lighting of your tank, and what you are intending to take pictures of, (fish or corals) you will find that ISO 400 is usually plenty fast. If you are taking coral pictures with a tripod, then I would set your camera to the LOWEST ISO number you can, as it will give you the least noise, and best color.

Color is another thing that is affected by ISO, the higher the ISO the duller the color, the lower the ISO the more saturated the color is.

Okay... I guess I have typed enough, on to the PICTURES!!!!


ISO 100


ISO 200


ISO 400


ISO 800


ISO 1600


ISO 3200

Now, NO ONE mention the Valonia but that is actually where the noise is most evident, the shadow area. As the ISO increases, do you see the "grain" or color flecks increase in those shadow areas? That is the NOISE.

Remember, noise is not the end of the world, it can be reduced in post processing, or even eliminated totally with programs like Noise Ninja. If you ever find yourself in a place where you have to increase the ISO to get a clear image, then by all means DO IT!! It is much better to have an image that is in focus with a little grain, then it is to have a blurry image from either camera shake or your subjects movement. (Bird in hand is better then 2 in the bush mentality.)

I hope you find this information useful, and by all means if you have any questions, post them here!

-Mike




Just say NO to CRABS! [sm=.gif]  Build Thread HERE -Mike
#1

Replies (6) Related Threads

    Hopkins
    MMMC Member
    • Total Posts : 333
    • Scores: 0
    • Reward points : 596
    • Joined:
    • Location: Royal Oak, MI
    • Status: offline
    RE: What is ISO and Noise? (permalink)
    0
    This is great info, I stuck it to the top!
    #2
    Poseidon
    • Total Posts : 307
    • Scores: 2
    • Reward points : 241
    • Joined:
    • Location: Swartz Creek, MI
    • Status: offline
    RE: What is ISO and Noise? (permalink)
    0
    Thanks Adam!!! I was coming back to do that, I forgot...
    Just say NO to CRABS! [sm=.gif]  Build Thread HERE -Mike
    #3
    sspl01
    • Total Posts : 1
    • Scores: 0
    • Reward points : 0
    • Joined:
    • Status: offline
    RE: What is ISO and Noise? (permalink)
    0
    I would say that Some degree of noise is always present in any electronic device that transmits or receives a "signal."  For televisions this signal is the broadcast data transmitted over cable or received at the antenna; for digital cameras, the signal is the light which hits the camera sensor.  Even though noise is unavoidable, it can become so small relative to the signal that it appears to be nonexistent.  The signal to noise ratio (SNR) is a useful and universal way of comparing the relative amounts of signal and noise for any electronic system; high ratios will have very little visible noise whereas the opposite is true for low ratios.

    Mack

    Michigan Alcohol Addiction Treatment
    #4
    clamdigr
    • Total Posts : 1088
    • Scores: 1
    • Reward points : 923
    • Joined:
    • Location: Orion, MI
    • Status: offline
    RE: What is ISO and Noise? (permalink)
    0
    Great info Mike, post processing is something I have yet to try. I don't have photoshop, but a stand alone version of Noise Ninja for $35 is pretty reasonable.
    -Mike-

    240g In-wall - 48x48x24 - Mixed Reef  
    #5
    witt
    • Total Posts : 10
    • Scores: 4
    • Reward points : 71
    • Joined:
    • Location: Melbourne, FL
    • Status: offline
    Re: RE: What is ISO and Noise? (permalink)
    0
    Damn Mike - your Canon even makes 3200 look good! It's like 400 on a Nikon D200.

    Love your tutorials. Much better than the pictures of stuffed monkeys elsewhere for seeing noise.
    #6
    BeakerBob
    • Total Posts : 53
    • Scores: 2
    • Reward points : 1768
    • Joined:
    • Location: Dewitt, MI
    • Status: offline
    Re: RE: What is ISO and Noise? (permalink)
    0
    Good thread Mike!!  Stay in a good mood and post more!
    #7
    Jump to:
    © 2017 APG vNext Trial Version 4.1