Aputure COB 120d DAYLIGHT Version

Mercatus said:
Just received the Cob120D today and did some comparisons to the LS1. Also got the fresnel in, feels kind of cheap, don't expect a smooth zoom from spot to wide on it.

If you put the fresnel on the 120d and set it to 25 degrees, you do get basically the same output of the LS1 1S. The spread of the LS1 1S is actually a little bit wider than the 25 degree setting of the fresnel, so I would say there's more light being output overall from the LS1.

Now here's the interesting stuff. The totally don't color match at all. The LS1 1S is green, which I've always noticed but it's never been a problem because it matches their other panels.

The 120d is more blue, and I dont' think I'd do a situation where I use one light like the LS1 as a key and a 120d as a fill. The color is way too different.

Another interesting thing, that Aputure fresnel has outlets for air, and boy does it let light leak all over the place especially as you go more spot. Having black wrap on standby will be a must with this light, kind of disappointing.

Lastly, be aware that the batteries you used for a COB120T or LS1 may not work for this light. I've got a 10.7 mAh Maxoak 158 Wh batteries and the light turn off immediately when at 100%, and won't stay on very long when over 90%.
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Thanks for doing the comparison! That's quite a few gotchas!

I'm not surprised that the overall output is at least very close. After all, the power draw is so similar.

Regarding color, have you tried actually measuring the difference? Not necessarily with a color meter (who actually owns one of those expensive yet very desirable toys?!?), but perhaps just doing a custom wb with your cam with both and then pulliing the raw still or video into a program to see what the offset is?

The light is officially 6000k as opposed to 5500k or so for the Ls1s, so it's already off in terms of being cooler. I can't say I've noticed green with my Ls1s. However, it is warmer than my dracast by a touch.

That's weird about the battery, especially not being the same as the 120t. Very weird.
 
Yeah trying to measure the actual color differences is next, I've got a plan for that and will post the results.

I never noticed that the Ls1s was green until Kholi pointed it out on a shoot...now I can't unsee it, I wish he hadn't told me haha!

Apparently the COB120D requires a battery capable of at least 11Ah. My 10.7Ah battery doesn't cut it, so unfortunately I've got to add the cost of a new battery to the overall cost of this light.
 
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Apparently the COB120D requires a battery capable of at least 11mAh. My 10.7mAh battery doesn't cut it,
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Er - sorry?

Ampere-hours are a measure of capacity. Milliampere-hours would be an extremely small measure of capacity.

What batteries do you have?
 
Comparing the open face LS 1s to the 120d COB with fresnel really doesn't make sense. They are so different. Once the fresnel is attached the beam will be much narrower than a 1x1 LED panel regardless of the 25 degree angle of the LS 1s. I would look at what your needs are and choose that way. Output alone is limiting.

The COB 120d is very versatile. Yes the fresnel is a little clunky but I really don’t mind since it's cheap at $69 and gets the job done. The light leak hasn't been an issue and if causes any simple black wrap will fix that. I rarely focus a fresnel to be super tight. For me it’s all about light control. My issue with the fresnel is the barn doors i have aren't very good. I need to find better ones. The front of the fresnel is the standard size of the front of the included modifier so universal barn doors designed to fit will work.

Here are my tests. I included for comparison the ARRI 650 at full wide.

Aputure COB 120d With Fresnel at 42˚
10 feet 158 FC

Aputure Light Storm Ls1s (25˚)
7 feet 383 FC
10 feet 190 FC

Arri 650
10 Feet 91 FC (54˚)
 
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So turns out it's always interesting to measure light vs eyeballing it.

To my eye, the COB120d look cooler, and the LS1s looked warmer and more green (I've always thought this was from a color fringing effect at the edges of the light, but not sure).

I aimed both lights at both a white card, aimed up my Ursa Mini 4.6K at it, and took an white balance reading.

LS1s: 5747 with a tint of +17.49

COB120d with fresnel at 25 degrees: 5545 with a tint of +32.62

Each reading was done three times to check for consistency.

Turns out the COB120d measures warmer than the LS1S, and it has more green in it, so the camera has to compensate by cranking up the tint.


For what it's worth, I also shot a color checker chart lit by each light. I then took this the footage into Resolve and ran a color match to see how the values of each color box changed when compared to a target gamma.
This is kind of my standard test to check for color accuracy since I dont' have a nice modern color meter.

Results for the LS1s: Aputure LS1S Color Checker Match Values.JPG

Results for the COB120d: Aputure COB120d Color Checker Match Values.JPG

So while the overal color of the COB120d measures more green than the LS1s, it still is on average, more accurate over the color spectum than the LS1s.

Here's a Dropbox link to 2 uncompressed DNG's of the chart in case anyone wants it: https://www.dropbox.com/sh/disrh0aec22ezhj/AABwFfDvMIGR4X9Ct1MnvgHsa?dl=0

Obviously this isn't necessarily useful info to anyone else, but it's part of my process to get familiar with the lights I use and I thought I'd share it. Anyone who's dealt with big HMI lights knows how much those lights can require correction gels and would say the differences between these LEDs is minor in comparison.
 
One issue with using a camera for testing a lights color accuracy is that all cameras have a different color science so what you get from a URSA will be different than a Sony FS5 or Canon C300. I really want a CRI Color Meter but just can’t afford the $1700 price tag unfortunately.
 
Further testing...

The specifications in the Aputure manuals for the COB120t and COB120d show the daylight version to have, on average, a 30% increase in lux output over the tungsten version.

Erik Naso actually reported an 45% increase in light output for the daylight version over the tungsten (without fresnels).

This is most definitely not the case for my daylight light. My 120d's output matches the output of my 120t, I've checked this mathematically and there is no difference.

My light meter chose a 5.6 f-stop for a target value for both lights.

Unfortunate, as I was definitely hoping to sell my COB120t and buy additional 120d's, just gel them to tungsten when needed, and not lose too much output compared to having the tungsten fixtures.
 
Mercatus said:
Further testing...

The specifications in the Aputure manuals for the COB120t and COB120d show the daylight version to have, on average, a 30% increase in lux output over the tungsten version.

Erik Naso actually reported an 45% increase in light output for the daylight version over the tungsten (without fresnels).

This is most definitely not the case for my daylight light. My 120d's output matches the output of my 120t, I've checked this mathematically and there is no difference.

My light meter chose a 5.6 f-stop for a target value for both lights.

Unfortunate, as I was definitely hoping to sell my COB120t and buy additional 120d's, just gel them to tungsten when needed, and not lose too much output compared to having the tungsten fixtures.
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I took foot candle readings from both lights at the same distance with the same Sekonic meter in a controlled environment. I stand by my tests that I performed. I'm not making this stuff up.

Aputure COB 120t TUNGSTEN
7 feet 79 FC
10 feet 36 FC

Aputure COB 120d DAYLIGHT
7 feet 115 FC
10 feet 58 FC
 
So what is the opinions as far as good companion fill / hair lights that match closely to color temperature for the COB 120D?
 
Does this light need batteries to operate even plugged in?

Mine seems to be auto shutting off after a few seconds and I can't get the fan to seem to spin. Tell me I'm doing something wrong and I don't need to return, please.
 
jimmiesner said:
Does this light need batteries to operate even plugged in?

Mine seems to be auto shutting off after a few seconds and I can't get the fan to seem to spin. Tell me I'm doing something wrong and I don't need to return, please.
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The battery is an option.

Batteries need to be 11Ah min. If it's not it shuts down.

The fan wont come on unless it needs to cool it down.
 
Mercatus said:
I never noticed that the Ls1s was green until Kholi pointed it out on a shoot...now I can't unsee it, I wish he hadn't told me haha!
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If the LS1S is green, then what would you say my Dracast LED 1000 "Pro" is! Hah. I see a magenta shift on the LS1S and a definite green on the Dracast.

I tried the 120D at the local shop the other night. The 120D looked light it throws light a lot further than the LS1S, (without the fresnel attachment.) Almost bought one over the LS1S, but prefer the form factor of a flat panel.

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Hi, Does anybody have problems with theyr cob120d? Mine dyed after 2 weeks, on actual shoot. Returned it to seller and waiting for repair or exhange.
Also i have ls1 and zero problems through 2 years but ....
 
Quick transportation question about the cob 120. Really like the size for packing in a case full of lighting gear however it does not come with any type of protective cap for the LED chip. How durable is that LED? Hoping to pack it in a crowded 1650 without it's reflector mounted as I have a bunch of reflectors stacked together. Any insights or suggestions on a protective cap for this light?

thanks, jeff
 
lightstand said:
Quick transportation question about the cob 120. Really like the size for packing in a case full of lighting gear however it does not come with any type of protective cap for the LED chip. How durable is that LED? Hoping to pack it in a crowded 1650 without it's reflector mounted as I have a bunch of reflectors stacked together. Any insights or suggestions on a protective cap for this light?

thanks, jeff
Click to expand...

What about pvc pipe caps??
 
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