Imago Metrics: Beamorama

FLASHLIGHT REVIEWS

Beamorama:

The following 'Beam shots' are simulations of some typical beam subject patterns. Additional patterns will be added as they become available. An single LED Flashlight's subject beam falling on a light gray wall, will most likely have characteristics that represent both the type of emitter used ( High Dome, Low Dome or Side Emitting ) as well as the collimating system. Reflectors, optics and combinations of reflector and optics have a significant influence on how light that is emitted from an LED is modulated. Added to this is the further influence of 'focus'- that is, the position of the emitter in the reflector.

Carefully formulated optics and reflectors deliberately modulate and in most cases- collimate- light from a source towards the subject in one of several patterns. These include:

Spot focused ( reflector or optics)
Flood ( reflector )
Combination Spot & Flood ( reflector or optics )
Specialized ( fiber optic / ultra wide)

Ideally- beams should be matched to the tasks for which a particular flashlight is intended to be used.
Modular or user-modifiable flashlights, allow for an easy interchangeability of optics or reflectors which give 'host' flashlights the added flexibility of performing a wider range of tasks.

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All Beams Simulations created in Freehand MX & Photoshop 7
Contributing Authors:
#1 Streamlight TL-3 LED - Erik Smith (CPF ID = idleprocess)
#2 UK4AA eLED - Erik Smith (CPF ID = idleprocess)
#13 Lambda Turbo-Mate, #14 TnC KeyLux (Aten Imago)
© 2004 - Imägo Metrics LLC

Longbow Micra- Reflector VS Optics - Comparison
Set-up parameters:
Flashlight lens to target distance = 81cm
Camera lens to target distance = 129cm
Ambient illumination- low, to reduce contrast range
Exposure - 1/8 sec at f 2.8
ISO - 100 WB = Daylight (Color eliminated in samples shown)

+ ENLARGE + - Caution! - Large File Size
Actual Beamshot with SO17XA - Reflector	Actual Beamshot with Stock Longbow ( 6º Carclo?)

Summary Comments

SO17XA
This reflector provides a highly context inclusive illumination window or 'profile'. A moderate sized hotspot provides spot illumination and 'throw' while an expansive corona creates a wide, if dimmer surrounding illumination - giving the view 'situational context'.

The SO17XA scored a Maximum Distance for Object Identification (MDOI) at 128 ft

Outdoors- the wide corona provides some close-range illumination while also illuminating subjects into the distance. This has many practical applications such as: Hiking/Walking, Camping, Security/Police, Bicycling and General Foraging- where peripheral illumination is important.

Indoors - the wide corona excels indoors by illuminating a full 80º angle of view- enough to blanket 1/2 of a room with direct light- while creating a very bright focus at the hotspot. In ceiling bounce mode, the SO17XA adequately replaced low-level overhead illumination, bouncing a beam 5' in diameter from a table located 3.5' from the ground- throughout a 12'X18' room.
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Stock Longbow Collimating Optic- 6º (Carclo?)
This optic provides a slightly context inclusive illumination window or 'profile'. A hotspot about 50% wider than that from the SO17XA is surrounded by a dimmer rectangular frame of light that is in turn surrounded by a series of progressively darker bands of corona. A larger and brighter hotspot than the SO17XA, the light coming from the optic is visibly brighter and the throw is visibly further. Situational context is limited to the region immediately surrounding the hotspot.

The Stock Longbow 6º Optic scored a Maximum Distance for Object Identification (MDOI) at 140 ft

Outdoors - the narrow corona and medium/wide hotspot brightly lit a larger section of 'backyard' and at a significantly further distance than the SO17XA- making this arrangement ideal for searching especially over a greater distance, over water, under water, through fog or smoke or into deep 'holes'. This would be less appropriate for situations that call for a wider combination beam- such as bicycling or campsite foraging.

Indoors - the narrow corona doesn't easily illuminate large expanses of interior space but nonetheless, the beam allows for extremely bright spot illumination- useful in tactical/defensive as well as in mission critical situations such as search and rescue operations or any situation calling for a far-reaching spot light. Again, the stock optic can be used to direct light into light colored ceilings for a bright overhead lighting that gives a general subdued level of illumination.
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Conclusions
These two options are equally effective for general flashlight tasks- each having a special niche or strength. Owned as a set, they extend the capabilities of the host flashlight. The collimated light of the stock optic is ideal for narrow and efficient direction of light towards a specified target with some 'spill', while the SO17XA reflector broadens the beam to allow for easy visibility of nearby objects, paths, terrain and indoor spaces. This is the principle behind 'focusing' heads that allow for continuous variable beams angles. Having the ability to swap reflector with optic and visa versa- makes for context relevant flexibility. Because both of these options for the Longbow flashlight (and other flashlights) have somewhat overlapping characteristics- either one would serve admirably as a general-purpose accessory.