ISO settings in nikon f100

[vishwanath_chandrahas]

<p>Hi all,<br /> can anyone there explain me <strong> ISO settings</strong> of the Nikon f100 compared to a digital camera? Do I have to work out differently for the film and digital camera? If i use a film of ISO rating 100 (Ektachrome 100VS), what should be the optimum ISO I can set on camera (please explain with respect to shooting in both day light and night). Do similar ISO value produce different amounts of grains in digital and film camera? I heard film camera are more sensitive to ISO than the digital.<br /> Thanks.</p>

[William Michael]

<p>In simple terms, ISO is a reference to light sensitivity.<br>

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The ISO setting on a film camera only adjusts the camera's light meter . . . I cannot think of any other function for it, on a film camera. If you have a film with a SENSITIVITY rated at ISO100 setting the film camera's ISO setting will not affect the FILM - only the light meter reading and thus your exposure, if you use that camera's reading. The point I am making is, there are film cameras without any ISO selection on them and those cameras work fine.<br>

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On a digital camera however, the ISO selection is an intricate technology which in summary and simple terms makes the sensor more or less sensitive to light. On a digital camera if you set the ISO to 100 then the sensor will have a LOW sensitivity to light, thus it would be a good selection for daylight - on the other hand if you select ISO 1600, the sensor will have an HIGH sensitivity to light hence that would be good for indoors, without flash as another example.<br>

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Comparing films of ISO100 and ISO1600, the ISO 1600 film will most likely have more GRAIN - in the digital world, when you set the camera to ISO 1600 it will likely have more NOISE.<br>

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***<br>

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Specifically:<br>

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<em><strong>If i use a film of ISO rating 100 (Ektachrome 100VS), what should be the optimum ISO I can set on camera (please explain with respect to shooting in both day light and night). </strong></em><br>

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This film should be exposed at ISO100 - as mentioned, setting the ISO on a film camera only affects the light meter in that camera. If a film is exposed at a different rating - it is usually pushed or pulled (different time) in development to compensate.<br>

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<em><strong>"Do similar ISO value produce different amounts of grains in digital and film camera? I heard film camera are more sensitive to ISO than the digital."</strong></em><br>

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Again you are NOT comparing the cameras, but the digital camera and the film . . . I do not know what is meant by "<em><strong>more sensitive to ISO</strong></em>" but there is the correlation that the higher the ISO the more grain or noise.<br>

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What you might be meaning is, there is a capacity with digital to have very high quality at higher ISO settings - like some of the Professional Digital SLRs are producing good images at ISO3200 and ISO6400.<br>

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WW<br>

</p>

<p > </p>

 

[Alan Marcus]

<p >Photographic film consists of a coating of light sensitive chemicals coated on a transparent flexible material. Three light sensitive salts of silver are used. Each has a different sensitivity to light. Silver iodine had the lowest sensitivity followed by silver chloride while silver bromine has the highest sensitivity. Films are made by blending these three to achieve different sensitivities also called film speed. Additionally the sliver salts are crystals that are grown much like the rock candy process. The size of the crystals also determines sensitivity. Larger crystals are more likely to be hit by photons. These are the agent that trips off the crystal and causes it to become developable. Additionally trace metals such as cadmium and gold are allowed in. These have also increased sensitivity. </p>

<p > </p>

<p >After all the ingredients are mixed, the finished film is tested for sensitivity to light. A value is assigned according the rules established by the International Standards Organization based in Paris. </p>

<p > </p>

<p >Your camera has a light meter that measures scene brightness. This meter electronically tells you how to set your shutter speed and aperture for correct exposure. Grain in the finished print is seen when salts of silver clump together. This clumping is accentuated when the film has a high ISO or if the film is over developed. Because faster films have larger crystals thus grain is more likely to become visible. </p>

[nogub]

<p>You should not do anything that's not loading the film and start shooting. The ISO isn't originally something made in the camera, it is something in the film, films with a bigger ISO need less time to get enough light, one with a slower ISO is used for sunny days or making long exposures because you will need more time in the shutter.</p>

[vishwanath_chandrahas]

<p>I got it. Increasing or decresing ISO on the camera for a film of 100 ISO just affect the exposure (may cause a little over or under exposure) that' s all. Am I right? Other than that no effect on the grains. So it's only the type of film that matters here.<br>

thanks all.<br>

- vish</p>

[William Michael]

<p>Yes.<br>

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I think you have it!<br>

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Please note that if you have a ISO 100 film, and you underexposed it, or over expose it, the grain will be slightly different, than if you exposed it correctly. </p>

<p>This applied to all film.<br>

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WW</p>