I shoot with a canon 50mm 1.4. When I shoot a family of 4 or more, I would like to use an aperture of 4 or higher. When I raise my aperture, I am having problems exposing correctly. My shutter speed will be too low. I don't want to use a high ISO to adjust for this. Any suggestions?
IMO this is a case of a photographer who is either, 1) very stubborn, 2) unfortunately uninformed or 3) just plain silly.
I do not see any way around thinking of the exposure triangle as a three legged stool. That is what the rules of physics require us to do as photographers. Like it or not, we do not have the opportunity to have the universe bend to our whims.
Refusing to adjust one leg of an unstable stool can only result in lopping off a section of the other two when you are on very uneven ground. Keep cutting off only those two while trying to achieve balance and eventually you will no longer have a stool.
Those of us who shot film remember the limitations of film speed and the rather obvious results of needing to finish a roll of film poorly suited to the lighting conditions of the moment.
Thing is, those days have no relation to these days.
While killing some time last night, I came across an article which suggested
ISO is the value you set first and adjust last.
Actually, when you think about it, that's not bad advice.
Go into any situation, any scene, any location and you should be first assessing the light available to you as a photographer. If you are not doing that first, then nothing else you will do subsequently really matters.
Most any tutorial on photography will suggest a "proper ISO" value for general lighting conditions. To ignore these recommendations is to ignore all else that matters in photography.
"Light" is the material a photographer works with. ISO is one of the tools they use to turn that material into a photographic result.
I hear a lot of student photographers saying things similar to the op here. They are afraid of ISO because they do not understand ISO. The reviewing press has drilled it into their head that ISO is only of value at 100 or less. They are, as students, as hesitant to raise ISO as a student cook is adverse to adding salt. In both cases, the results speak for themself.
If I may directly address the op for a moment ...
Look, the camera manufacturer has provided you with a set of tools. One of those tools is "ISO" and yet another is "auto ISO".
If you are such an advanced student of photography that you realize you must add supplemental light sources when you intentionally restrict the amount of light entering the lens, then you will naturally add supplemental light sources to compensate for your aperture and shutter speed adjustments. That is one of your options in such a case.
However, if that were the case, you wouldn't be posting your statement, "I don't want to use a high ISO to adjust for this."
The proper response to your statement is, "What you do not do is continue to lop off chunks of the other two legs of the stool." If you do not want to raise ISO, you must either lower the aperture value or increase the shutter speed. Both of those options will have a direct result on your desired result. Of the three legs you have to work with, ISO is the most benign in its effect.
In other words, what you are telling us is you just don't care to use the actual tools of photography. You simply want photography to take care of itself and provide you with a well exposed photo despite your unwillingness to learn just how to go about achieving that result.
Doesn't work that way.
Therefore, would you kindly explain to us why you "don't want to use a high ISO to adjust for this"? Why are you not using the tools that came with your camera? What other tools are you not using?
White balance?
Auto or manual focus?
Jpeg vs RAW?
If you were, say, a plumber and you were doing work at my house, you wouldn't be doing any more work at my house if you told me you just didn't want to use solder to join two pipes which required a solder connection.
If you were a carpenter and you told me you didn't want to use a saw to trim a board to proper length, you would quickly find yourself on the unemployment line.
If you were a physician and you didn't want to use a stethoscope, you would probably end up being sued.
You have tools at your disposal, use them. That's why they are there. No true craftsman ignores the basic tools of their trade.
ISO is simply a value which determines the sensitivity to light for the recording media. Unless you can either replace or repeal the laws of physics, you cannot escape the simple fact you are dealing with a three legged stool.
Remember - or learn - the basic rule that says your print size is one of your first considerations when setting up a shot. As it relates to ISO, this means ISO is relative to the final print size. Printing at 4X6 or 5X7 means digital noise is drastically less noticeable at any given viewing distance than when you enlarge to 20X24.
There is no reason for most student photographers to fear ISO. Which loosely translates into, there is no logical reason not to increase ISO when the situation requires that you do.
(Should digital noise become a problem at a point where you are printing at large sizes, there are more than a few very good software options which will gently remove noise with little to no effect on image quality. Do your research.)
The lesson you should be learning is, your camera has provided you the tools necessary to assist in the success of your photographic journey. Set your camera to "auto ISO" and then set your limit to the top ISO value you wish to work at.
For most modern DSLR's this should be somewhere in the range of 1200 or so. Allow the camera to make the necessary adjustments to ISO in relation to your adjustments of the other two legs of the triangle.
If you feel you can nudge down the ISO value and still obtain the shot you desire, then do so. Otherwise, trust your camera to turn out a respectable exposure value. That's precisely what you do with the other tools your camera has provided.
Print your shots and ask someone who is generally unaware of what ISO value means to digital noise to judge which shots are (technically) less good. Don't do this yourself because you have already established a bias against raising ISO and you will know which shots to see as less good.
I'd be willing to bet, if you aren't printing at very large sizes and viewing from very close distances, no one will even mention reducing ISO.
Take that as your lesson in ISO values.