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grandadraymond
20th of March 2010 (Sat), 13:16
I never shoot in manual mode, but ive been trying it out today the Manual says you set all the settings yourself, Ok im using a Canon 40D just for this question i will use these settings shutter speed 1/250 Aperture f5 my problem is i just cant set the exposure all the photos i take are just Black and the exposure dial is at -2 and flashing you probably think in stupid ok maybe i am but how do i get the correct exposure i am also using my 70-300IS lens thank you:oops:

hawkeye60
20th of March 2010 (Sat), 13:19
There are three factors involved, you set two of them, the third is ISO. You'll need to set that too.

grandadraymond
20th of March 2010 (Sat), 13:22
Yes sorry i set the iso to 400 this was daylight on a cloudy day

keitaro
20th of March 2010 (Sat), 13:23
You need to get the exposure dial over to 0. Your metering the scene to be -2, and you need to compensate. Either adjust your shutter speed, or aperture to achieve it. If you cannot get a fast enough shutter speed to achieve your shot, increase your ISO.

grandadraymond
20th of March 2010 (Sat), 13:32
Thank you i just took a couple of shots and think im getting the hang of it now, so am i right in thinking you cant get 1/250 in any conditions without a f2.8 lens

D Thompson
20th of March 2010 (Sat), 14:40
...so am i right in thinking you cant get 1/250 in any conditions without a f2.8 lens
No. 1/250 is very easy on a sunny day. Take a good sunny day, set at ISO 200, 1/200th and f16 and you should be good.

Lowner
20th of March 2010 (Sat), 14:59
Manual does not mean you must ignore the camera meter, just use it while applying a large dollop of commonsense.

There is a well known expression that might be useful. Known as the "Sunny 16 rule": On a sunny day, ISO100, shutter speed 1/100s, aperture f/16. Adjust any of these parameters and another has to change to compensate.

Snydremark
20th of March 2010 (Sat), 15:19
There are three different factors in an exposure:

Aperture: This is how wide the opening in your lens is that lets light in to the sensor.

Shutter speed: This is how long the light is allowed to hit the sensor to make your exposure.

ISO: This is how sensitive the sensor is to the light that hits it. A higher number means it's more sensitive.

You can get 1/250 shutter IF you have enough light to work with, but if you're shooting on a cloudy day there just may not BE enough light for that high of a shutter speed.

There are 2 things you can adjust to get more light in and one thing to increase your sensor's sensitivity to the light that reaches it.

Aperture: The opening in the lens that allows light through to the sensor. The smaller this number is, the larger the actual opening. F/5.6 is a somewhat small opening and doesn't allow a lot of light through. So I would imagine that this is as far as you can go with that lens.

Shutter speed: The amount of time that the shutter is open to allow light to reach the sensor. On the 40D this can be as short as 1/8000sec or as long as 30sec; this is going to be the largest control you have in that sort of light. Obviously, the longer you set this the more light will reach your sensor and increase the brightness of the shot. The tradeoff is that unless you have the camera on a tripod, any shutter speed under about 1/320 of a second will start to generate blur from camera shake.

ISO: How sensitive your sensor is to the light that reaches it; analogous to film speed in a normal camera. The higher this number, the more sensitive your sensor is; so you can increase this try and get a higher shutter speed.

These are really rough basics and there are plenty of good books out there to read more on. Might try Understanding Exposure by Ryan Peterson for more info.

Sorarse
20th of March 2010 (Sat), 17:57
To address a comment in your original post, your meter was flashing -2 and your pictures came out black because you underexposed them. The meter flashing -2 was the camera's way of telling you that the picture would be undereposed with the settings you chose.

There may be some circumstances when you may deliberately wish to underexpose an image, depending on the circumstances of lighting and subject matter. Knowing when to do that will come with experience.

In the meantime adjusting your shutter speed/aperture/ISO or a combination of the three so that your meter is not flashing at you should produce an image that you can at least work with if it's not spot on.

grandadraymond
20th of March 2010 (Sat), 18:32
Thank you everybody i think ive cracked it now i appreciate all the advice...Ray

Lowner
21st of March 2010 (Sun), 07:14
Sorarse,

"At the beginning of time there was absolutely nothing. And then it exploded! Terry Pratchett"

Apparently the "Big Bang" theory is being seriously re-examined by some powerful science because some of the "facts" don't seem to fit with the theory very well. Wasn't there another quote "I always knew there was something seriously wrong with this universe"?

mattyb240
21st of March 2010 (Sun), 08:11
Understanding Exposure - Bryan Peterson!

egordon99
22nd of March 2010 (Mon), 05:46
Understanding Exposure - Bryan Peterson!

Ditto.... bw!(excuse the "pun" :lol: )

Once you figure out the relationship between ISO, f-stop, and shutter speed, photography becomes much more clear.

neilwood32
22nd of March 2010 (Mon), 08:04
Try having a look at Ben's Newbie guide (http://photography-on-the.net/forum/showthread.php?t=414088) in this forum - a very good place to start.

+1 for "understanding Exposure" as a starter book as well