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mary13
21-06-2011, 8:25pm
Hi all

Hoping I may be able to find an answer here in regards to Exposure Compensation as am a complete Beginner.
I tried taking some Sunset shots over the city this afternoon. I have been having trouble with the the Exposure Compensation meter (-2.1.0.1.+2), in my Canon EOS 1000D Handbook, they call it the Exposure level Indicator. Anyway, the needle is sitting on the (-2) and will no move no matter what I do, even changing the Shutter Speed and Aperture, it will not move which is very frustrating as a beginner! I have the ISO set to 100.
We were told that the when the needle sits in the middle on the (0) you will get a sharp picture. Up until now, the Exposure level mark would centre in the middle on the (0) if this makes sense.

Not sure if I have changed some settings without realising, I have checked the Metering mode is still set to Evaluative Metering, the Auto Exoposure Bracketing is off.
In the Introductory Photography course I have just completed, we were advised to only use Manual, not TV or AV. I have been reading some of the threads regarding AV and am going to try the AV setting for a while and see how I go with it.
Thank you in advance
Mary

Scotty72
21-06-2011, 8:31pm
Can I assume you are in Tv or Av mode?

Not M?

Scotty72
21-06-2011, 8:36pm
If you are, the the indicator will not move.

What it does that (For eg if you are in Tv mode) when you set the desired shutter speed, the camera will use the light meter to then set the appropriate aperture. But, the -2 setting you have means that the camera will deliberately set the aperture to expose 2 stops under correct exposure.

(same applies to Av setting - but it will adjust the Shutter)

What you are trying to do will work in M mode.

That is, you pick either the aperture you want (or the shutter speed), then you adjust the shutter (or aperture) until that needle gets to the correct exposure.

Get me?

Scotty72
21-06-2011, 8:38pm
So, if you are using Av mode, you need to find out how to adjust the 'exposure compensation' on your camera. Once you do, increase the compensation (that needle) until it reaches 0 (or whatever you want).

OK?

ricktas
21-06-2011, 8:40pm
OK firstly who ever told you that if it is set to 0 it gets you a sharp picture was wrong!

The exposure indication is for that, the exposure, not sharpness. Your camera meters the scene and from that determines what it thinks is the correct exposure to get a good range of brightness from the dark black shadows to the bright highlights, from this reading your camera tries to ensure that you are not over-exposing (blowing out highlights to pure white) or under-exposing (to much pure black) in the result. It has nothing to do with image sharpness.

Exposure compensation and Exposure level indicator are also two different things. Exposure compensation allows YOU to adjust the exposure metering from what the camera 'thinks' it should be. So say you set the Exposure compensation to -2, then your camera will take an exposure meter reading and then under expose the resultant photo by 2 stops from what it determined was correct, cause by setting Exp Comp to -2, that is what you are telling the camera to do. I suggest you adjust exposure compensation back to ZERO and leave it there, whilst you are learning how to take better photos. Work on your shutter speed, ISO and aperture for now, and leave exposure compensation alone till you have a better understanding of the inter-relationship of the 3 main elements.

By having exposure in the middle at zero, you will get a well exposed photo, based on light levels the metering system detected, and the limitations of the dynamic range your sensor can capture in one shot. Sharpness is a result of the quality of the lens used, focus point and shutter speed, more than anything else. Exposure compensation doesnt play a part in image sharpness.

Scotty72
21-06-2011, 8:40pm
Try not to think of it as an 'exposure compensation meter'. It is an 'exposure compensation indicator'.

ie. It is not showing you what it is metering, it is showing you what you have set (in this case, you have set it to -2).

Only, when you are in M, does it actually show you what it is seeing (and not what you set).

Confused yet? :p

kiwi
21-06-2011, 9:03pm
Great, another course that teaches manual and f all else of use :rolleyes:

mary13
21-06-2011, 9:05pm
Hi Scotty and Ricktas
Thank you for taking the time to reply, I am really confused now!!
Scotty, I have been in Manual mode and the needle will not move at all. Could you please explain what you mean by: ie. It is not showing you what it is metering, it is showing you what you have set (in this case, you have set it to -2).
Do I need to worry about the Exposure Compensation Indicator in Manual mode???
Ricktas, I have the Exposure Compensation set to zero and am leaving it there for now until I get the hang of it all.
I cannot get the needle to move at all from the -2, it is like it is stuck there, prior to this I could get the needle to move to the middle when changing the Shutter Speed and Aperture.
Hope this makes sense in Beginners language.

ricktas
21-06-2011, 9:07pm
I think you have inadvertently changed something in your camera menu that is causing the -2 then. If you cannot find what you did. Do a reset. This will restore your camera to factory defaults.

Kym
21-06-2011, 9:10pm
NTP to the rescue...

http://www.ausphotography.net.au/forum/showlibrary.php?title=Indexes:Appendix_C_-_Camera_Metering_measuring_light_and_Sunny_16_rule

agb
21-06-2011, 9:11pm
If you are using M mode then the needle should move if you are changing shutter speed and or aperture. That is the way it works in M for you to get the correct exposure.
Forgive me for asking, but I have done it myself, you have got the lens cap off.
Try changing the ISO,making it much faster, ISO 400 or 800, perhaps if you are doing this right now then it is simply too dark and you are either not gettiing the shutter speed low enough or your lens aperture cannot go down far enough.

Kym
21-06-2011, 9:13pm
BTW Start with ISO 400 and use Av mode - shutter speed should be ok at ISO 400 and reasonable open apertures.

On Pentax (I assume Canon is similar) you push the Ev button and dial in +/- Ev, There should be a way to do that on the Canon and set it to Zero. Lookup Ev in the manual

Scotty72
21-06-2011, 9:17pm
ahhh locked the exposure... Good thinking 99...

But, taking a photo should clear that? Doesn't it?

mary13
21-06-2011, 9:37pm
Ricktas, can you advise how to do a reset, I have a Canon. I will try finding it in the Handbook as well.
Scotty, excuse my ignorance! What is Locked Exposure??
Kym, I am going to try using AV mode for a while and see how I go although my thinking is to Manual at the moment, I will try increasing the ISO as well.
agb, I did check I had the Lens cap off as I have made that mistake before, haha!

Scotty72
21-06-2011, 9:44pm
I'm not sure if it is the case (I rarely use it and can't remember its behaviour) but, most DSLR have an exposure lock feature (usually a button). Once pressed, it will lock the exposure - so, if you move the camera (and the light changes) the camera wont change its settings.

What I am not sure of (on your camera - and mine is upstairs) is, will it also lock the needle on the indicator. Sorry, too tired to go upstairs to check it on mine. :(

But, once you take a picture (by default) it should clear that setting.

Scotty

Maezyra
22-06-2011, 1:15am
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
------------------0
''''''''''''''''''''''''''''''''''''''''''''''''''''''''''' - 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.

Boofhead
22-06-2011, 5:01am
Hi Mary, it can get confusing can't it? It might be that the values you currently have will require that you make quite a large adjustment in shutter speed or aperture until the needle starts to move. I would recommend setting your camera to auto mode and take a photo. Have a look at the settings the camera decides are best for the scene you are shooting, ISO, shutter speed and aperture. Then switch your camera back to manual and use those settings as a starting point take a photo of the same scene again. As long as the lighting has not changed too much you should see your setting near 0.

Hope this helps and good luck :th3:

ricktas
22-06-2011, 5:38am
Ricktas, can you advise how to do a reset, I have a Canon. I will try finding it in the Handbook as well.


Not sure for Canon Mary, It's just a menu item in Nikon camera's and it lets your reset and remove all the settings you have made and returns the camera to how it was when it first came out of the box when bought.

camerasnoop
22-06-2011, 7:04am
I hesitate to weigh in here, because poor Mary's head must be spinning with all the advice she has received, but if you want to reset your 1000D you'll need to do thgat in the menu. You can either look through your menu system to find it, or you can remove BOTH batteries from the camera. When you put them both back in though, you'll need to enter the date and time again and reset everything you've customised. I gather that you probably haven't intentionally customised anything anyway.

I'd then visit Canon's website and download and install any firmware updates available for your camera model.

If the problem persists, consult a camera doctor. ;)

agb
22-06-2011, 7:28am
Has this been solved?

mary13
22-06-2011, 1:14pm
Hi all
Thank you so much for taking the time to reply. The problem hasn't been fixed.
I am currently at work so will not be able to check my camera until later tonight.
I read my Canon Handbook and found how to reset the camera to factory settings which I am going to do tonight.
Will let you know the outcome.

Scotty72
22-06-2011, 1:46pm
Good luck :th3:

FallingHorse
22-06-2011, 3:46pm
Mary - I have the EOS1000D and although I am at work at the moment I will happily PM you how to reset all of your settings so that it revert to the 'factory settings'. I wont be home until around 9pm (NT time). Hopefully you will have a cure before then but I will check.

Can you tell me if you are still getting the -2, when framing other shots in different light? The exposure compensation dial I think is only relevant if you are shooting in Tv or Av because in Manual is your shutter/aperture/ISO combination is the exposure compensation dial.

soulman
22-06-2011, 4:38pm
If you are using M mode then the needle should move if you are changing shutter speed and or aperture. That is the way it works in M for you to get the correct exposure.
Forgive me for asking, but I have done it myself, you have got the lens cap off.
Try changing the ISO,making it much faster, ISO 400 or 800, perhaps if you are doing this right now then it is simply too dark and you are either not gettiing the shutter speed low enough or your lens aperture cannot go down far enough.This seems the most likely issue to me Mary. Some people seem to be missing the fact that you're shooting in Manual and giving instructions that don't apply to this mode, which is making this much more confusing than it needs to be.

Firstly, you need to verify that things are working OK, so point the camera at a bright light or take it out during the day to confirm that the exposure needle will move when there is enough light.

If you can get it move, then the sunset shots you were trying to do were just too dark for the camera & lens combination you have. Deal with this by using a tripod - which allows you to use a longer shutter speed - or increasing the ISO as agb suggests. Do make sure you're adjusting things in the right direction - the shutter speed and aperture need to be adjusted to their smaller numbers, both of which let more light get to the sensor.

If you can't get the needle to move at all, even in bright light, then there may be a fault with the camera. Simply turning it off will clear any exposure lock you might have accidentally set - there is no need to reset the camera to clear that - and we can probably assume you have turned it off since yesterday, so let's hope it was just too dark the other day.

Do let us know the result though. It will help others in the future who may come across a similar problem.

mary13
22-06-2011, 5:02pm
Thank you so much Scotty, Jodie and Soulman, you people are great.
Can't wait to get home and check my camera now.
Will let you know how I go.
Kind regards
Mary

Scotty72
22-06-2011, 5:05pm
Thank you so much Scotty, Jodie and Soulman, you people are great.


Awww! shucks :p :lol:

Maezyra
22-06-2011, 5:42pm
Can you tell me if you are still getting the -2, when framing other shots in different light? The exposure compensation dial I think is only relevant if you are shooting in Tv or Av because in Manual is your shutter/aperture/ISO combination is the exposure compensation dial.

I know that with my Nikon, Ev does affect Manual Mode. Please refer to my test under my own post about this very issue - http://www.ausphotography.net.au/forum/showthread.php?62289-Over-Exposure

kiwi
22-06-2011, 6:29pm
I was about to say the usuall fix for a canon fault is to follow these steps

1/place canon camera on floor
2/ smash it with a hammer
3/ buy a nikon

Simple eh ?:rolleyes:;):D

Kym
22-06-2011, 6:52pm
http://www.youtube.com/watch?v=uDHQ5lXZGTo&feature=player_embedded

Maezyra
22-06-2011, 7:35pm
I was about to say the usuall fix for a canon fault is to follow these steps

1/place canon camera on floor
2/ smash it with a hammer
3/ buy a nikon

Simple eh ?:rolleyes:;):D

:lol: Love your work!!

FallingHorse
22-06-2011, 7:49pm
Hi Mary
If you press 'Menu" then scroll over to the 3rd 'spanner' tab. "Clear settings' is the second on the list. When you press that you have a choice, "Clear all camera settings" or "Clear all Custom Functions"
"All camera settings" will revert to the factory setting mode and "Clear all custom Functions" will clear anything you have set as a Custom Function in the Custom Functions menu.
The other option is Cancel :)

Hope that helps

Scotty72
22-06-2011, 8:21pm
I was about to say the usuall fix for a canon fault is to follow these steps

1/place canon camera on floor
2/ smash it with a hammer
3/ buy a nikon

Simple eh ?:rolleyes:;):D

Typical camera envy humour by those lacking the judgement to not buy a Nikon. :cool:

mary13
22-06-2011, 8:31pm
Hi all
I am ready to try the usual fix for a Canon fault, LOL!
I have tried clearing all Camera settings back to default and have also cleared all Custom functions back to default and the needle is still sitting on the -2 and flashing.
Don't know what to try next, maybe I will give Canon a call tomorrow and see what they say.
I have tried changing the Shutter Speed and Aperture and it will not move even inside the house with the lights on.

Scotty72
22-06-2011, 8:35pm
Could u post a pic showing the rear screen - so we can see. ?

Kym
22-06-2011, 8:39pm
Seriously, I'm calling a camera fault. At least go to the local camera shop or Canon service and get the local tech to have a look

Scotty72
22-06-2011, 8:42pm
Seriously, I'm calling a camera fault. At least go to the local camera shop or Canon service and get the local tech to have a look

Increasingly, It would seem that way. :(

mary13
22-06-2011, 8:55pm
Scotty, can you believe I do not have another camera in the house to be able to take a picture of the rear screen, if I did I would. I will take the camera to work tomorrow and ask a friend to take a photo of it for me.
Kym, I am going to go to the Camera shop tomorrow after work and show them to see what they say, the guy at the local Camera House is very helpful.
Will be just my luck it will fix itself by then.

Scotty72
22-06-2011, 9:01pm
Don't u have a mobile ? :eek:

agb
24-06-2011, 7:36am
Scotty, can you believe I do not have another camera in the house to be able to take a picture of the rear screen, if I did I would. I will take the camera to work tomorrow and ask a friend to take a photo of it for me.
Kym, I am going to go to the Camera shop tomorrow after work and show them to see what they say, the guy at the local Camera House is very helpful.
Will be just my luck it will fix itself by then.
Mary how did you get on with this? Has it been sorted out?

Irru
24-06-2011, 8:57am
I find myself thinking how lucky I was/am to have had the canon g10 to do my initial learning on, where so much has a physical knob for it - including exposure comp.

If you're still confused, despite so many good posts trying to explain it, here is my suggestion for getting a good feel on the various modes, and the role of Ev in each. Hopefully your camera is able to do what I'm suggesting - because there is no better way to learn than by playing with the camera, and hopefully this explanation helps you to visualise it.

Set up the subject and the camera
1. Put it in 'live view' (which is where you look at the LCD screen rather than the viewfinder.
2. Put the live histogram into your live view. This should be a menu setting. The histogram shows the exposure of the whole image.
3. Set your Ev to 0.
4. Construct/find a scene in your house, to take pictures of, where you can get comfortable and even rest the camera on a pillow/table etc (or tripod if you have one). Try to pick a scene that is neither too bright nor too dark.

Next, put it in Av mode.
1. Look at the histogram. Most of the data ought to be represented in the middle of the histogram, perhaps a bit like a bell curve.
2. Adjust the aperture setting from one extreme to the other, and keep an eye on both the histogram and the shutter speed that the camera is automatically selecting. The histogram should stay roughly the same, while the shutter speed will change dramatically - and predictably. (The Ev indicator will stay on zero through this, except perhaps at the absolute extreme ends, which is the camera telling you that there is no way to take a correctly exposed picture with the aperture that small/large).
3. Now leave the aperture at one place, while adjusting Ev from one extreme to another. You should notice that the shutter speed changes a bit, while (for the first time) the histogram also changes. As you go to -Ev it should bunch to the left, and to +Ev it will 'bunch' to the right. With the picture itself also getting darker and lighter, respectively.

Next, try it in M mode
You will need to set both shutter speed and aperture yourself of course. Pick a neutral sort of aperture (F5-8, doesn't really matter). Now adjust the shutter speed back and forth, watching both the Ev indicator AND the histogram. They should appear to mimic each other, but they are slightly different.
The histogram is showing the actual exposure.
The Ev indicator is showing the exposure in relation to what the camera thinks it ought to be (zero). Adjust the shutter speed until the Ev indicator reaches 0. That shutter speed is what the camera would automatically have chosen for you if you picked the same aperture in Av mode. The histogram should resemble what you saw before, in Av mode.

Usefulness of the Ev indicator in M mode?
When looking through the viewfinder, when you don't have a histogram, it is your training wheels. It is the camera telling you, "Hey er, you're doing nicely and all, but I reckon you need to expose that more/less."

Truth is, M mode isn't really necessary unless you want to override what the camera wants to automatically do. If you're going to use M mode and expose with the Ev indicator at zero, you may as well just use Av/Tv mode instead.

Boo53
24-06-2011, 9:28am
If it wasn't a camera fault perhaps these youtube tutorials from adorama might help

http://www.youtube.com/watch?v=mb2qQhuk_Rk&feature=bf_prev&list=PLBC5A73FEA8B7D7D2&index=23

http://www.youtube.com/watch?v=VlSuInza16E&feature=bf_prev&list=PLBC5A73FEA8B7D7D2&index=17