Mary,
Fret not - We will get this sorted. It happened to me awhile ago (only in the other direction) and it was posted by me in the help section under "Over-Exposure". As for the locking of the exposure and all of the other features - maybe it's best to leave those for now, and just focus on the absolute basics, otherwise you will go out of your mind trying to learn everything all at once. In my Nikon, I go through the menus until I find the "Reset to Factory Default" or something similar to that and I press okay.
On my Nikon, I accidentally adjusted my Exposure Compensation (which is what Nikon call the Ev setting that you have described above) when learning to use Av setting (As you know from another one of my posts, Kiwi, I also did a "Manual Only" course). I clicked it over to Av and tried to change the aperture the way I would if I were in Manual. This, of course, had no bearing on the aperture, it changed the Ev setting instead. What I didn't understand at the time is that in Av mode, you use the wheel to set the aperture and the camera does the rest for you (hence being a semi-automatic mode) - I was so used to setting everything. Then I clicked over to Manual again and everything I took for a month was over-exposed or I would just assume that the camera was doing strange things and guess what the shutter speed should have been, not what the camera was telling me it should have been. It was a complete accident in changing this and I didn't know what I was doing wrong until Ricktas and Kiwi pointed this out to me in the above-mentioned post.
Let me see if I can explain this visually...
Imagine you are taking three pictures of the same scene and you are using your
light meter to get the correct
exposure
''''''''''''''''''''''''''''''''''''''''''''''''''''''''''' - This is where your normal setting would be - It is taking a true reading of the light that is around. Your Ev would be set to 0. (Please excuse the "---" before the 0 - when I posted it, it took out the spaces and defeated the point of what I was trying to explain. They are only there to keep the 0 where I want it to be. This is the same for the following two sections).
When you set your Ev to a negative, this happens...
------0
''''''''''''''''''''''''''''''''''''''''''''''''''''''''''' - When you change the Ev setting to -1, for example, the camera moves the point where the "0" is. So the light meter will tell you that it is in the middle, but in actual fact, the light meter is not giving you a "true" reading, it is assuming that there is more light around than what it detects and is compensating for it. It would tell you to have a shorter shutter speed than what it would if the Ev were set to 0 and if you were to take a picture, using the light meter as your guide, it would appear under-exposed.
If you were to set your Ev to a postive value...
--------------------------0
''''''''''''''''''''''''''''''''''''''''''''''''''''''''''' - When you change the setting to +1, for example, the camera has moved the point where the light meter would read as "0". Because the Ev has been set to a positive value, the camera assumes that there is actually less light than what it detects and compensates accordingly. The camera would tell you that you need a longer shutter speed than what it would if your Ev were set to 0 and if you were to take a picture, it would appear over-exposed.
I know this is all very confusing, Mary, but it is a marvellous learning curve. Once you make a mistake such as this as a beginner, you learn about what that function does. You learn how to avoid it as a beginner and then, later on, how to use it to your advantage (Although, I am still not at that point when it comes to Ev. I always have it set to 0 for now). You are doing really well and it is great to see that you are embracing your photography in such a way!!
Chin up and keep at it!!
Erin.
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Originally Posted by mary13
