Overexposing Color Film

<p>I am using a Nikon N90s camera and wonder do I need to overexpose color negative film to improve overall texture and sharpness? For instance setting the ISO at 200 when shooting ISO 400 speed film. And what happens when I set ISO 400 speed film to 800 or 1600? Can anyone help me out on this.</p>

<p>Yes you should.</p>

<p>Not necessarily. Depends on the film. Some may benefit from a little down-rating from the nominal ISO, some don't. Also depends on other factors, including the lighting. What film are you using? What are the exposure conditions?</p>

<p>Back in the film days it was always recommended to overexpose colour negative film by 1/3rd of a stop. For instance; Kodak VPS (rated at iso 160), exposed at iso 125.<br>

I always stuck to this and have never been disappointed.</p>

 

<p>So if I am outdoors shooting Fuji Reala iso 100 speed film on a bright sunny day I should overexpose 1 stop and set the camera to ISO 80?</p>

 

<p> Leo, 80 is 1/3 stop from 100. 50 would be a full stop with 64 in between. Also, you're not necessarily overexposing anything here, the 80 might just be the optimum exposure index setting on your camera to get the proper exposure with your particular film, it's still ISO 100 film. In particular, you don't want your camera's settings to continually underexpose the shadow areas so this is a main reason why the old "rule of thumb" was to drop the film ISO setting some to compensate for inadequate exposure in print film. Often in slide film, we would set the opposite way, to prevent overexposure in the highlights. Once you know the characteristics of how your film behaves in your camera in a particular lighting scenareo you can then get consistancy and duplicate your results in the future. Hope this helps some.</p>

<p>If your negatives are not dark enough at the rated sensitivity, you are probably not metering correctly. Correct metering requires good tools, skill, decisions and compromises. If something you want is in the shadows or if you have a bright cloudy sky dominating the scene, measure what you want to shoot and don't think you can just point an averaging meter in the general direction of the subject.</p>

<p>Read "The Camera" and "The Negative" by Ansel Adams. Many of the concepts illustated in his books apply to color, even digital photography.</p>

<p>Ditto, Edward's comment. Some claims (not all, of course) regarding the perceived need to down-rate film are based on careless metering technique. It helps to know your camera's metering pattern so you'll know what it "sees" and whether it's adjusting appropriately for strong backlighting, an overcast sky, etc. I blew my share of film before I recognized the metering quirks of each camera. For example, the OM-1 was very vulnerable to metering error from bright sky light entering the viewfinder. If I hadn't tried an eye cup to block the extraneous light I might have jumped to the erroneous conclusion that my film or processing was faulty, because I knew I was metering the scene correctly - I simply failed to recognize that the meter was seeing more than what appeared through the lens.</p>

<p>If you meter accurately and consistently most color negative films are fine at the nominal ISO. Among the very few exceptions I encountered was Fuji NPZ, which - subjectively speaking, of course - seemed better at around EI 640 than 800; while the consumer grade Fuji Superia X-tra 800 seemed fine at 800.</p>

<p>But it's easy enough to test for yourself. Devote a roll to methodical tests. Bracket each exposure to take at least two otherwise identical frames of each photo, one at the rated film speed, another at 1/3 to 1/2 more exposure. You don't necessarily need to reset the ISO for each shot. Just change the shutter speed or aperture, or use the exposure compensation feature and let the camera do the rest.</p>

<p>Besides following good practice in exposure you should think about the way your film will be developed.</p>

<p>If you change labs often it is up to your guess and a +1/2 to +1stop overexposure might be a good idea.</p>

<p>Using my F5 a few years ago I liked the consistency of the metering. After I decided to develop my film myself ( for real professional labs I had to mail film and I did not want this) I was really impressed by the F5 metering. What a difference a precise development made! I used a single time developer kit to develop 5 135 films per tank. In reasonable light conditions all frames were perfect. I did not even know how good the F5 was until I stopped using different and non-pro labs.</p>

<p>Another thing is to adjust your development to your scanning. Films have an optimal density for scanning but of course this needs to correspond to your scanner. If your scanner is capable of getting denser areas with little noise then you can develop some films a bit denser.</p>

<p>For example I used the Fuji 160 S pro film for high contrast light outdoors. My Nikon scanner CS8000 handles a bit denser negatives well and I exposed according to 130ISO and pushed 1/2 stop in development. You may want to try a number of films because everybody exposes a bit different. You also may need a little experience for different light situations.</p>

<p>And as you know every film type is different and you may want to start with just one or two types of film that you use most and only later expand your selection if necessary.</p>

<p> </p>

<p>There is a benefit to shooting 1/3rd to 2/3rd stop over the rated ISO for better overall density and shadow detail. Unless the printing is way off, you will most always get better color fidelity with a good dense neg than from a thin one. Remember most meters will underexpose in many situations. For black and white film I would set my meter at half ISO most of the time.</p>

<blockquote>

<p>"Remember most meters will underexpose in many situations."</p>

</blockquote>

<p>I haven't found that to be the case as often as my own metering technique has been flawed. When I've methodically tested my TTL meters in controlled lighting on gray cards and color charts against my calibrated handheld spot and incident meters, it turned out most of my camera TTL meters were within 1/3 EV.</p>

<p>I suspect the main cause for underexposure with many cameras is stray light entering the viewfinder. That's often a problem in SLRs with metering cells in the prism. In a few cases I've seen low sunlight over my shoulder influencing the meter reading of my F3, which seems unusual because the metering cell is behind the mirror.</p>