Reviews You Can Rely On
We buy all the products we test — no freebies from companies. If you purchase through our links, we may earn a commission, which helps support our testing.

Black Diamond Cosmo Review

A good light, but caught in a no-mans land between better lights and cheaper lights
gearlab tested logo
Black Diamond Cosmo Review
Credit: Abriah Wofford
Price:  $35 List
  • 1
  • 2
  • 3
  • 4
  • 5
Manufacturer:   Black Diamond
By Jediah Porter and RJ Spurrier  ⋅  May 28, 2018
58
OVERALL
SCORE

RANKED
#11 of 27
  • Trail Finding - 35% 4.0
  • Close Proximity - 20% 9.0
  • Battery Life - 15% 5.0
  • Weight - 15% 6.0
  • Ease of Use - 15% 6.0

Our Verdict

While this is a good headlamp, we implore you to spend another $10 and get something like the Black Diamond Spot which has much better beam brightness and quality combined with a very respectable battery life. The Cosmo is a middle of the road kind of light. It offers average performance and average battery life at an average price. If you are on a budget, look to the Petzl Tikkina which scored slightly better for a fraction of the price.
REASONS TO BUY
Lightweight
Small size
Excellent flood lighting
REASONS TO AVOID
Below average spot beam
Disappointing low-mode battery life

Compare to Similar Products

(change comparison)
 
black diamond cosmo
This Product
Black Diamond Cosmo
Awards   Best Buy Award
Best Headlamp for General Purpose Use
  
Price $35 List
$34.95 at REI		$29 List$24.95 at REI
Compare at 3 sellers		$19.95 at REI
Compare at 3 sellers		$19.00 List
$14.99 at Amazon
Overall Score Sort Icon
58
63
60
56
52
Star Rating
  • 1
  • 2
  • 3
  • 4
  • 5
  • 1
  • 2
  • 3
  • 4
  • 5
  • 1
  • 2
  • 3
  • 4
  • 5
  • 1
  • 2
  • 3
  • 4
  • 5
  • 1
  • 2
  • 3
  • 4
  • 5
Bottom Line A solid product overall, but priced precariously with cheaper lights offering more for lessA good value that offers basic functionality, slightly better than average performance, at a good priceThe $20 Tikkina is a great light around the campsite, for general use, in your thingy drawer, or car glove boxOur favorite budget light if your needs are limited to close proximity workA good light, but not great, sold at an attractive price, but the Tikkina is a better value
Rating Categories Black Diamond Cosmo Yalumi LED 140-Lumen Petzl Tikkina Black Diamond Astro Energizer Vision HD
Trail Finding (35%)
4.0
6.0
5.0
3.0
3.0
Close Proximity (20%)
9.0
5.0
4.0
7.0
5.0
Battery Life (15%)
5.0
6.0
7.0
6.0
6.0
Weight (15%)
6.0
6.0
6.0
6.0
6.0
Ease of Use (15%)
6.0
9.0
10.0
9.0
9.0
Specs Black Diamond Cosmo Yalumi LED 140-Lumen Petzl Tikkina Black Diamond Astro Energizer Vision HD
Measured Beam Distance 66 m 94 m 62 m 38 m 45 m
Claimed Distance 65 m 90 m 55 m 35 m 40 m
Measured High Mode Run-time (ANSI) 3.9 hrs 4.3 hrs 3.5 hrs 4.8 hrs 8.7 hrs
Claimed High Mode Run-time 45 hrs Not specified 60 hrs 20 hrs 8 hrs
Measured Low Mode Run-time 39 hrs 47 hrs 223 hrs 95 hrs 74 hrs
Claimed Low Mode Run-time 180 hrs 100 hrs 220 hrs 80 hrs 8 hrs
Measured Weight 3 oz, 86 g 2.7 oz, 77 g 2.9 oz, 83 g 3 oz, 86 g 3.1 oz, 89 g
Battery Type 3 AAA 3 AAA 3 AAA 3 AAA 3 AAA
Water Resistance IPX8 waterproof beyond one meter IPX4 splash proof IPX4 splash proof IPX4 splash proof water resistant
Manuf Claimed Lumens 200 lumens 140 lumens 150 lumens 150 lumens 180 lumens
Beam Type flood/spot, dimmable flood/spot flood flood, dimmable flood/spot
Red Light yes yes no no no
On Switch Lock yes no no yes no

Our Analysis and Test Results

The Cosmo is a solid headlamp with good performance overall, and excellent flood lighting for close proximity use. At $30 list, it falls into a tough price range where a little more money gets you a much higher performance headlamp, like the Spot, and products like the Tikkina offer better overall performance for 33% lower price.

Performance Comparison


black diamond cosmo
Credit: Abriah Wofford

Trail Finding


A score of 4 for trail finding is disappointing for a $30 headlamp, and most similarly priced competitors offer significantly better performance.


Beam Distance Photos
Beam photo of Black Diamond Cosmo
Beam photo of Black Diamond Spot

Black Diamond Cosmo
Black Diamond Spot

In comparing the Cosmo (above left) and Black Diamond Spot (right), two products from the same manufacturer and priced just $10 apart, it is remarkable that they can vary so much. The Spot casts a much superior distance beam.

Close Proximity


The strongest performance from the Cosmo is when used around camp, or in the tent, for close proximity work. The flood beam is one of the very best of all headlamps we tested, wide, evenly lit, and dimmable from nice soft lighting for use in the tent, and brighter for use in the camp kitchen. It is worth noting that the Black Diamond Astro offers a flood beam that is nearly as good, at a price 33% lower.


black diamond cosmo
Credit: Abriah Wofford

Battery Life


Battery life is where the Cosmo edges slightly ahead of the Spot.


black diamond cosmo
Credit: Abriah Wofford

Weight


At 3.0 ounces or 86 grams, this is a compact but not ultralight headlamp. It is about the same weight as the Spot. For comparison, the featherweight champion Petzl e+LITE is less than a third the weight at 27 g.


Conclusion


This is a solid light but tough to justify buying. At $30 list it is wedged between competitors that either score much better for another $6-10 or offer the same or better performance for lower cost. The BD Spot, for example, performs significantly better for only $10 more. It has a nearly identical form factor and mass with a much better beam. On the low-end, the Petzl Tikkina offers better all-around performance at 33% lower cost.

— Jediah Porter and RJ Spurrier
 
Table of Contents

You Might Also Like