Help with snowy, sunny conditions

[ItsAllAboutTheSass]

We will be heading into the Laurel Highlands (east of Pittsburgh) tomorrow. They are expecting 4-6 inches of the white stuff. I have never used my t2i before in these conditions (only had it about 2 months). My 2 lenses are the 18-55 stock lens and the 50mm 1.8. Any advice would be great.

[pilotdane]

It will all depend on the conditions when you are there and what you are photographing. If you plan to use your camera in a non automatic mode I would read the manual where it discusses metering. This basically determines where the camera looks at the scene and determines how to expose the image. This can range from looking at the whole scene in general down to mostly basing the exposure on a small spot in the center.

[pierces]

A good rule of thumb is to overexpose by 1 to 1½ stops using the exposure compensation. The camera will try to meter the snowy scene to an average 18% grey and the snow will come out muddy grey and people/non-snow parts of the scene will be very dark. By over-exposing you will render the snow white and all else normal.

 

Most modern camera have a scene setting for Snow/beach that essentially does the over-exposure for you.

 

Dave

[TheRoff]

Here is a second to Dave's under exposure recommendation. Also, if you have nice deep blue skies, which I hope you do, take a meter reading of the blue sky opposite the sun. Lock that exposure and frame your image. The exposure should be well within the ball park. (This recommendation basically comes straight from Bryan Peterson's "Understanding Exposure," which is a great book.

 

It does work.

 

 

 

Larry

[ItsAllAboutTheSass]

Thank you for your replies.

[Turtles06]

A good rule of thumb is to overexpose by 1 to 1½ stops using the exposure compensation. ...

 

Dave

 

Dave, when you say "stops" here, do you mean EV? In other words, you are saying to overexpose by 1EV to 1.5 EV?

 

Thanks!

 

(I know you should overexpose for snow, just didn't have a good feeling by how much.)

 

I really appreciate all the info on here!

[pierces]

Dave, when you say "stops" here, do you mean EV? In other words, you are saying to overexpose by 1EV to 1.5 EV?

 

Thanks!

 

(I know you should overexpose for snow, just didn't have a good feeling by how much.)

 

I really appreciate all the info on here!

 

Correct.

 

1 "stop" equals 1 EV (Exposure Value). A "stop" refers to the detent positions on the old lenses that "stopped" the aperture setting at f/1.4, f/2, f/2.8 etc.. Each full unit increase in EV doubles the amount of light reaching the sensor (or film). Each full unit decrease halves the light. You could do the same by setting the exposure manually and then bumping the f/stop, shutter speed or ISO up or down but the exposure compensation wheel lets you make the adjustment while using the camera's autoexposure capabilities.

 

Technically, EV refers to a fixed scale based on EV0 being equivalent to an exposure of 1 sec at f/1.0 at ISO100 (really dim...out doors in moonlight). Old light meters would read all of the light in a scene and give a reading in EV and a chart would tell you what exposure to set. A snowy scene in bright daylight would read about EV16 and for ISO100 you would set the shutter to 1/1000 and the aperture to f/8. To overexpose, you would read the chart setting for the next highest EV (EV +1) or the next lowest to underexpose. When you "adjust EV" on the camera you are adding or subtracting a compensation to the meter reading. If you are using artificial light, you can alter the EV of the scene by adding or subtracting lights or adjusting the power on your flash but outdoors puts you at the mercy of nature and that's where exposure compensation comes in.

 

Modern evaluative metering bases its exposure on an average of readings from several areas of the scene and can be fooled by situations where the scene is predominantly bright or dim. It is increasingly common that sophisticated "Program" modes on cameras will detect problem scenes and compensate automatically.

 

Dave