Over the past few months, this light meter has become my constant companion! It is incredibly easy to use, and I’ve tailored the settings to perfectly suit my workflow. For instance, I am back to using single readings with exposure memory—in contrast to a while back, when I used to let the meter measure continuously.
Whether I’m shooting with a Rolleiflex SL26, Rollei 35, Hasselblad 503CX, or Contax RTS—even though these cameras feature built-in light meters, the Hedeco Lime I is always with me. Whether it's for double-checking a reading, metering for low-sensitivity films (like Fuji Superslow 1.6 ISO / Fujichrome CDU II), or managing long exposures exceeding 30 seconds, it serves its purpose beautifully!
This is not a paid advertisement—just my own opinion based on real-world experience.
But why should you use a handheld light meter?
Reflected-Light vs. Incident-Light Metering: Comparing the Two Methods
Thanks to its specific metering characteristics and analysis functions, a handheld light meter offers capabilities that no built-in camera meter can match. Naturally, you need a handheld light meter for cameras that don't have a built-in meter from the factory. This applies to all large format cameras, many medium format systems, and "vintage" analog 35mm cameras without autofocus. However, a handheld meter can be an highly effective tool for all other photographers as well.
Skeptics might argue that the modern matrix or multi-segment metering systems inside modern cameras deliver highly reliable exposure results. In many cases, this is absolutely correct. However, modern multi-segment systems tend to "babysit" the photographer regarding what constitutes a "correctly exposed" image, while leaving them in the dark about any automatic exposure compensation the camera might be applying behind the scenes. As a result, the photographer never learns the subtleties of necessary exposure adjustments.
Take, for example, metering a subject standing in front of a very bright background. If I rely on a built-in light meter using center-weighted metering, my main subject will inevitably end up underexposed. Because the meter is fooled by the bright background, it will select a shutter speed that is too fast or an aperture that is too small. In this scenario, you would need to lengthen the shutter speed or open up the aperture (or use a combination of both parameters).
Technical Background: Center-weighted averaging is well-suited for many shooting scenarios, which is why it was the standard metering method in many analog 35mm cameras for a long time. In evaluative or average metering, brightness is calculated across the entire image area. Center-weighted metering simply places more statistical weight on the center of the frame. This method is particularly useful for centered main subjects or when paired with an exposure lock. Slight changes in framing affect this metering method far less than pure average metering.
Of course, more modern analog 35mm or medium format cameras offer additional internal metering modes, such as partial metering (where a small percentage of the frame is used to determine exposure, e.g., 6.5%), spot metering (where the area is even smaller, e.g., 1%), or even multi-spot metering (where the camera averages the readings from multiple selected areas). However, all built-in light meters rely solely on what is known as reflected-light metering.
Reflected-light metering measures the light reflected by the subject. Because of this, every light meter always assumes that the scene matches a standard subject, reflecting an amount of light that consistently equates to an 18% gray value. The calibration of every camera meter is tuned to this standard. It is easy to see how the actual amount of light can vary wildly depending on the subject, the time of day, and other scene characteristics. This, in turn, misleads the built-in meter, resulting in incorrect exposures.
In controllable lighting environments, you can achieve this ideal value by taking a reflected reading off an 18% gray card placed near the subject within the most critical part of your frame. Ideally, you target the gray card using a spot or partial meter, lock the reading, remove the card, and then take the actual shot.
Incident-Light Metering with a Handheld Meter
Handheld light meters also allow for the much more precise method of incident-light metering. Incident metering measures the actual light falling onto an object. This method is only possible with a handheld meter because you must measure from the subject's position, pointing the meter back toward the camera.
This method has the distinct advantage of measuring the light entirely independent of the subject's physical properties. It makes no difference whether the subject is bright, dark, or highly reflective. Backlighting and the color of the scene won't interfere or throw off the exposure reading. White surfaces stay white, black surfaces stay black, and reflections won't cause underexposure.
If you have the opportunity to take a reading directly from your subject's position (or from a spot with identical lighting), incident metering provides a level of accuracy that will challenge even the most advanced matrix metering systems in modern 35mm cameras—issues that often cannot be compensated for automatically.
Contrast Analysis via Multi-Spot Metering
All modern spot meters—whether built into a camera or used as a handheld device—offer a multi-spot metering function. If you measure the brightest and darkest critical areas of your scene, the multi-spot system will calculate the average. This yields an exposure value (an aperture and shutter speed combination) that factors both areas equally into the equation. Of course, this method won't stop highlights from blowing out or shadows from crashing if the scene's dynamic range is simply too extreme.
However, by metering the brightest and darkest areas that still need to retain visible detail, you can determine the overall contrast range of the scene. This allows you to analyze whether your film stock (or your sensor, if you are shooting digital) can actually handle that dynamic range.
For example, if your exposure reading in the brightest highlights calls for 1/1000s at f/11, and the darkest shadow area requires 1/8s at f/11, the total contrast of the scene is 7 exposure steps (stops). To find this, you simply count down the shutter speed scale backward from 1/1000s to 1/8s to get your result.
Based on this analysis, you can then decide whether you need to add fill light or modify the lighting setup entirely. If the scene contrast proves too high, you can use further targeted measurements to focus entirely on the most critical part of your frame, ensuring you get a correct exposure at least where it matters most.
