• You are viewing the forum as a Guest, please login (you can use your Facebook, Twitter, Google or Microsoft account to login) or register using this link: Log in or Sign Up

Technical Photography question

andyh

Member
Joined
1 Jan 2009
Messages
1,920
Location
Derby
Hello

Can someone give me some pointers/advice please?
web.jpg


How do i control the brightness, and the areas that almost look white with too much light in my photos.

I would like to know, what do i adjust on my camera, to get a better less bright/over exposed photo.

I have tinkered with a few things but i aint that techy when it comes to photography!

Thanks as always :thumbup:

Andy
 
I can't help you, but I imagine the first question (from the professionals) would be what body/lens are you using?

Then they may be able to point you in the right direction.

I'd be interested too anyway!
 
Andy, you need to meter on the brightest areas. As you rightly say, the brightest area is over exposed and lost, so you need to reduce the exposure by either increasing the shutter speed or reducing the aperture to allow less light through to the sensor. If you have a point and shoot, and its not possible to adjust these settings, it may be worth a try to aim the camera towards the top of the tank where the light is brightest and get a focus lock by pressing the button half way, this will also lock the exposure, move the camera down to your required shot and then fire the button.
 
aaronnorth said:
Take a look at this page here, it exaplins what is happening

viewtopic.php?f=35&t=9067&start=50

Thanks, Aaron


Aaron

Very useful i will have a play with that tonight, i have never really played with the metering settings, i used to be an turn it to Auto type photographer but in the last 12months i have been playing with AV, M, P, etc

George Farmer said:
Cameras will smaller sensors will suffer more from this as they lack the dynamic range.

It's also worth thinking about this issue from a light source perspective, rather than just a camera/settings one.

I understand what your saying there George about the sensor, i am using a Bridge style camera,(Canon Powershot SX1 IS) so its got all the manual settings capabilities but a fixed lens, although it does have CMOS sensor. But it will never be an SLR's :(

When talking about the light source, I have an Arcadia 4 x 24w and for this photo I am only using two tubes, so I am unsure what i can do? Any advice o_O
 
andyh said:
I have an Arcadia 4 x 24w and for this photo I am only using two tubes, so I am unsure what i can do? Any advice o_O

physically raise the light. This will spread the light more evenly around the tank, rather than an intense spot. or if you cant raise the light, make some kind of diffuser out of grease proof paper maybe?..... :D

George is right, look at the lighting.
 
The camera's metering (if set to all-frame or matrix mode) will look at the entire scene and decide what is the combination of shutter speed, aperture and ISO to get the best exposure. The "best" exposure will look like a volcano on the histogram. In this case, the camera sees the dark parts of the kitchen top and tries to brighten it up, therefore causing the highlights to overblow, i.e. white-out.

I'm not certain about the model of the camera you have, but if you can adjust the exposure compensation, i.e. +/- EV, give that a go. -1EV should be enough. The way I'd recommend is to use P-mode, set a fixed ISO, then take a shot as if shooting on auto. Note down the aperture and shutter speed settings. Then switch to manual mode, make sure the ISO, aperture and shutter speed are the same, take a shot. It should look exactly the same as the first shot. Now you can tweak the aperture and shutter speeds (one at a time, never both at the same time) to get a good exposure.

Just my 2 cents.
 
Back
Top