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Photography Question 
no 
BetterPhoto Member Since: 10/29/2005
 

Underexposure=darker picture right?


i always thought under exposing the film means it is darker and over exposing it means it's getting brighter.. but thinking about it made me realize it goes both ways. so if anyone could clarify this that'd be great.. heh. this is my last stupid question I swearrrrrr


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11/8/2005 4:54:04 PM

 
Brendan Knell
BetterPhoto Member Since: 4/17/2005
  Underexposing means that not enough light has hit the film or digital sensor and it is darker than it should be. Overexposing means that too much light has hit the film or digital sensor so it is brighter than it should be. I hope that this clears things up for you.


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11/8/2005 7:18:31 PM

 
Kerry L. Walker   Underexposure makes the negative thinner (lighter) and, thus, the picture darker. Overexposure makes the picture lighter.

Please don't quit asking stupid questions. If you do, we won't be able to give stupid answers. LOL


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11/9/2005 6:16:24 AM

 
no 
BetterPhoto Member Since: 10/29/2005
  another thing.. stopping down the lens means making the aperature smaller (16, 18, 22) and stopping up is making it wider right? like 2.8 etc.


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11/9/2005 7:11:16 AM

 
Kerry L. Walker   Yes, closing down means a smaller aperature (higher number) and opening up means a larger opening (lower number).


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11/9/2005 7:25:54 AM

 
Justin B. Renshaw
BetterPhoto Member Since: 1/27/2005
  To make things more confusing---It's just the opposite when shooting slide film.


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11/9/2005 1:35:04 PM

 
no 
BetterPhoto Member Since: 10/29/2005
  what do you mean? I shoot slide film so this could be a problem.. ha. could you explain this for me???


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11/9/2005 7:36:24 PM

 
Justin B. Renshaw
BetterPhoto Member Since: 1/27/2005
  When you overexpose slide film or (positive film) the slide gets darker and when you underexpose it gets/remains light. So it's better to overexpose slides
than to underexpose, just the opposite of negative film. I'm starting to confuse myself.


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11/10/2005 10:46:48 AM

 
Justin G.
BetterPhoto Member Since: 7/13/2004
  It's better to underexpose slide because light burns density away as to print, it burns density in.

Underexpose slide so you don't burn out details and overexpose film so you burn in details.


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11/10/2005 12:07:10 PM

 
no 
BetterPhoto Member Since: 10/29/2005
  how can over exposing and underexposing mean 2 different things i'm still unsure. sorry ot be such a bother haha thanks to everyone who's helping.


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11/10/2005 12:20:49 PM

 
Kerry L. Walker   Overexposing means you gave it too much light. Underexposing means you gave it too little light. Obviously they mean two different things. Whet everyone is saying is that it is better to overexpose negative film and better to overexpose positive (slide) film. However, I wouldn't underexpose slide film too much as the latitude of slide film is very narrow.


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11/10/2005 12:25:58 PM

 
Justin G.
BetterPhoto Member Since: 7/13/2004
  Ok when you "expose" and image you're "exposing" the film (or CCD/CMOS) to light. When you "over-expose" you've "over-allowed" the light in, meaning too much light. When you "under-expose" you're "under-allowed" the light inm meaning too little light. See what I mean

Overexposing - allowing too much light to hit the surface.

Underexposing - allowing too little light to hit the surface.


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11/10/2005 12:27:44 PM

 
Justin G.
BetterPhoto Member Since: 7/13/2004
  Thought of a good example.

Cooking a ham: directions say 350 for 20 minutes.

Let's say you cook it at 350 for 10 minutes, you're underexposing because you didn't give it enough time so it came out lacking the properties you wanted it (cooked).

Let's say you cook it at 350 for 40 minutes, you're overexposing because you gave it too much time so it came out exceeding the properties you wanted it.

Hope this helps.


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11/10/2005 12:33:32 PM

 
Kerry L. Walker   Yeah, most chefs underexpose their steaks!


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11/10/2005 12:35:36 PM

 
Justin B. Renshaw
BetterPhoto Member Since: 1/27/2005
  Now I need Help! With negative film, when you underexpose the negative-your print comes out too dark and when you overexpose the negative the print comes out too light,right? With slides it's the opposite meaning that an overexposed slide is dark rather than light, right?


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11/10/2005 1:31:27 PM

 
Justin G.
BetterPhoto Member Since: 7/13/2004
  Ok don't worry about the exact negative right now, that's a whole nother issue. The end result (a final print) of both slide and negative is that over-exp will be too bright and under-exp will be too dark.


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11/10/2005 2:42:52 PM

 
Kerry L. Walker   Justin, an overexposed slide is just like an overexposed print. It is too light. Remember, when you make a print from a slide you are making a positive from a positive while with negative film you are making a positive from a negative.


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11/10/2005 2:59:09 PM

 
Sharon  Day
BetterPhoto Member Since: 6/27/2004
Contact Sharon
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  Underexposed slide film will not scan well on a film scanner, at least not on my elderly HP S20.


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11/10/2005 3:16:09 PM

 
no 
BetterPhoto Member Since: 10/29/2005
  holy crap... CONFUSING.

Lemme recap and someone tell me if I sorta got it.

Underexposing film would result in a brighter negative (aka darker picture)

Overexposing film woul dbe the oppisite, Making a negative darker but the overall picture would be brighter.

If I got that down then i'm just confused on slide film.. why is it better to under or over expose it and how many stops under exposed should it be??


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11/10/2005 9:00:06 PM

 
Gregory LaGrange
BetterPhoto Member Since: 11/11/2003
gregorylagrange.org
  Got it.
It's better to get exposure correct. But slide film a little under by half, and not more, will make colors looks a little saturated. Going over with slides makes colors look bright and faded, like laundry faded clothes.
Negative film going under makes colors dull, sometimes muddy is the term used. Going over with negatives, you can add some extra to making the print, so you go some room to work with.


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11/10/2005 10:44:28 PM

 
Glen Taylor   "on slide film.. why is it better to under or over expose it and how many stops under exposed should it be"

To start, try 1/3 stop UNDER-exposure for color transparency (slide) film. Underexposing this film increases color saturation and is preferred by some photographers for some, but not all cameras and some, but not all transparency films (you have to experiment with your own camera's lightmeter, film, and subjects to find out what you like). But you normally don't need much. Overexposure of transparency film is almost never a good idea, because overexposure, even by 1/2 stop over, can often burn out the highlights or light-colored areas of the transparency and ruin it. Again, this film has a much narrower range of exposure than color negative (print) film. An easy way is to set the film ISO on the camera slightly higher, say 125 for 100 speed film.


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11/11/2005 6:56:20 AM

 
no 
BetterPhoto Member Since: 10/29/2005
  yeah I was gonna say can't you just push or pull the film... but my camera (N80) goes from 100 to 200 speed there is no 125.


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11/11/2005 11:21:09 AM

 
Gregory LaGrange
BetterPhoto Member Since: 11/11/2003
gregorylagrange.org
  Exposure compensation.


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11/11/2005 11:27:32 AM

 
no 
BetterPhoto Member Since: 10/29/2005
  is that the +1,2,3v thing thats in teh custom functions?


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11/11/2005 11:30:58 AM

 
Justin B. Renshaw
BetterPhoto Member Since: 1/27/2005
  So with slides- underexposure by 1/3 is a good rule of thumb or you can just change the camera ISO up a stop. I think that's why I previously stated that it's better to overexpose slides. I was cunfusing the ISO change with the apature.


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11/11/2005 1:10:58 PM

 
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