How to Use a Photo Light Meter
Introduction:
A photographic light meter determines the amount of light coming from a photo source or subject. The meter sends out a reading indicating aperture and shutter speed settings that ensure ideal film exposure. Many cameras on the market today have a photo light meter built into the camera function. This is fine for the average household photographer. For professionals or serious photographic hobbyist, an individual hand-held photo light meter is more suitable.
Built in Camera Photo Light Meter
Setting the ISO
- Locate the film speed window labeled ISO. Some cameras may label this window ASA. Procedure remains the same in either case.
- Locate the shutter speed outside ring.
- Lift up on the ring and rotate it towards the desired film speed. All numbers are not marked to scale. In most cases, there is 100 ISO followed by 200 ISO. The dot spaces in between represent 125 ISO and 160 ISO.
Take a Meter Reading
- Point the camera towards target photographic object.
- Look through viewfinder to see light source indicator. This is on the right side of the viewfinder. When the needle rises, there is increasing light source. When the needle falls, there is decreasing light source.
- Adjust the aperture ring and shutter speed as needed. This will cause the needle to rise and fall accordingly.
Set Camera Controls
- Keep camera focused on target object.
- Adjust aperture and shutter speed settings until indicator needle rests in the direct center of viewfinder.
- Find desired shutter speed and f-stop pair settings. This will provide desired light source to target object.
- With desired setting selected, take the picture.
Separate Hand-Held Photo Light Meter
Setting the ISO
- Locate the speed setting numbers on the inner dial.
- Rotate inner dial on meter calculator to desired speed setting. Select meters may be marked ASA as opposed to ISO. The procedure remains the same in either case.
- Read indicator dots between major marks of 100 ISO and 200 ISO. These indicate 125 ISO and 160 ISO.
Take a Meter Reading
- Uncover the light receptor by sliding the plastic incident market to one side.
- Point light receptor end of meter in direction of camera. Maintain direction of target object.
- Press meter switch button to activate photo light meter.
- Do not tip photo light meter upwards or downwards. This will take the focus off photographic subject. The reading will no longer be accurate.
Set the Calculator
- Maintain depression on meter button.
- Maintain directional aim on photographic subject.
- Move outside ring on calculator dial. This will also cause the needle to move. That is okay.
- Continue to move the outside ring until the calculator needle centers on zero.
Chose Camera Settings
- Once calculator dial is set, select desired shutter speed and f-stop combination. This should create a perfect alignment match.
- If not, set the shutter speed first.
- Select the aperture speed from in-between f-stop indicators. The shutter speed will remain at the previously set indication.
