150W LED (Similar to Alzo) Compared to 650W Fresnel

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Paul F

Veteran
Here is a comparison of a 650watt Fresnel and a 150 watt LED light. This light is similar to the Alzo 300 we've been talking about.

http://www.ebay.com/itm/261312998232?ssPageName=STRK:MEWAX:IT&_trksid=p3984.m1438.l2649

Fan noise - unacceptable for audio. I'm going to play with this a bit.

[edit] update- the fan was changed out to a quieter fan (22db vs 35db). I made a recording with a Tram TR-50 and I could not tell the difference with the light on or off. [end]

The lights are 6' from the subject
The camera was white/black balanced for each light in separate shots
The shots are split-frame in the screen-grab (either that or the subject had a terrible accident)
The LED is on the left
ISO 400
1/30
Shots were set up to be at 70 IRE on the face
Except for aperture, no changes were made on the camera between shots.
Fresnel frame is f6.0
LED frame is f8.5
Color was adjusted on each frame in Premiere to match the skin tone and cabinet colors.
The LED reflector is 7" wide


The shirt color is correct on the LED side
The green bag is correct on the Fresnel side
The wall color and artwork are correct on the LED side

The red, blue, and green on the pretzel bag seem to match closely.

 
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So a daylight balanced LED vs a tungsten fresnel? Kinda hard to compare the two, since exposures are diff. and also what camera were you using? I'd always be iffy on these kinda of results because tungsten always has a high CRI of 95, while LEDs really depend on the manufacturer (only bicolored or expensive ones seem to have good CRI).

http://www.youtube.com/watch?v=g2-k6RZF66U#t=22

This video shows how, while a lot of LEDs are OK, they don't really compare to how well tungsten comes off. Honestly, a certain colour coming off looking 'correct' under tungsten probably has a lot to do with how your camera reproduces colours, than anything else. There's also a chance that if you only set your camera to 3200K you're looking at an image turning tungsten into daylight, not actually reproducing the warmer colour temp your eyes see, but simulating daylight.

edit: also, does that particular LED have it's CRI rating written anywhere?
 
I continue to find CRI pretty meaningless. A (reasonably) low CRI light can look great - a high CRI light can look like crap.

You're dealing with "claimed" CRI unless you have the means to test yourself. If the color rendering is off enough to give a lower score, sometimes it doesn't seem to matter.

There's a lot of threads here dealing with CRI vs. actual footage look. Richard from Cool Lights has posted a lot of info as well. But bottom line is that CRI is sometimes pretty meaningless over 85 or so.

I've tested all my daylight sources using camera raw stills and photoshop. Kino's, HIDs, flos, etc. They're all rated fairly high. They all require different gels to get a neutral gray in the same testing conditions. The real test of a daylight fixture is "is it neutral or can it be gelled to neutral without losing meaningful power?" If there's a massive green spike, the answer's usually "no". Killing the spike can mess with everything else. Subtle bumps in the output or color temp being too high - if you can fix it with 1/8 or 1/4 minus greens, CTO's, etc. (I have yellowish flo's that need violet even), I'll accept that. Testing's the only way to really know if a light's worthwhile or not.
 
Interesting test - thanks Paul for taking the time to share it.
I don't have the time or resources to test all the new light fixtures that pop up so I appreciate it when others do.
 
IanTheM said:
Kinda hard to compare the two,
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I don't follow. Its a straight comparison.

IanTheM said:
I'd always be iffy on these kinda of results because tungsten always has a high CRI of 95 ....
Click to expand...

Which shows you how valueless CRI is; at least for me. A single number to express color is not meaningful. A plot of the color density is much more useful. Tungsten is only a standard of light because it was the only convenient artificial light source available for color film for most of color film's history. But tungsten is a really poor source of light. It stinks for blue, is ok for green, and has too much red. The results show that. We've come to know and love tungsten for it's warm light. But that doesn't mean it's a good light source. I'd rather have a flat color density curve like a microphone response graph and modify the color as I desire. Just like EQ.

IanTheM said:
Honestly, a certain colour coming off looking 'correct' under tungsten probably has a lot to do with how your camera reproduces colours, than anything else.
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The blue shirt is missing blue in the tungsten shot; the green is what it should be; the wall looks pink, which it is not. That's exactly what I would expect given tungsten's color density spectrum.


IanTheM said:
edit: also, does that particular LED have it's CRI rating written anywhere?
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No it didn't. But it did come with a manual printed in what I expect is one of the Chinese languages. I'm sure it's full of useful information.
 
Great test! It would be interesting to see a shadow cast by the LED (like the one cut by... maybe it's a cart handle, in the tungsten shot on the right).

My Alzo 3000 won't cut a perfect shadow, because of the array... a slight stair-stepping. But it's better than any other LED fixture I've seen that gives that multi-shadow effect when used as a hard source.
 
Thanks Paul, always great to share stuff like this. Everyone can take away from it what they will.

You said the LED was on the left? The left side of the image - or the left side of the subject? I see a ton of magenta on the right side of the image, and the left side seems "whiter"?
 
BrownCowVideo said:
It would be interesting to see a shadow cast by the LED (like the one cut by... maybe it's a cart handle, in the tungsten shot on the right).
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There are a couple of shadows you can see on the left side of the cabinet. Clearly softer than the Fresnel. The LED array is quite wide on this unit; much wider than the Alzo. It is in a circular grouping (see picture in the link of the first post). That may help get away from the typical LED panel stuttered shadow pattern. If I have some time, I'll get a close shot of the shadow.

By the way, the RPS unit is even cheaper. Now $220, down from $250.
 
Great, Paul, thanks. Yes, I can see the shadows in the cabinets.

For the Alzo unit, there's a discussion going around about the fan noise from the light. I'm running a test on that today with my unit. What's the fan noise like on your RPS light?
 
Thanks for the test. I'm still looking into LEDs, particularly the Mole Richardson LED Fresnels.

Speaking of the Alzo, it uses a Bowens mount, which would allow you to use this reflector: http://www.bhphotovideo.com/c/product/254364-REG/Bowens_BW_1878_High_Performance_Reflector_for.html

It would significantly increase the output. I know this because I have a lot of studio strobes with high output reflectors, and the difference in power is surprising. I'd imagine the Alzo comes with a 7 inch "wide-angle" reflector, which isn't efficient for shooting into a frame with reflective or translucent fabric, for example.
 
Yes, the Alzo, RPS, and Nicephoto all use the Bowens mount, which allows for many different attachments. That is one of the attractions.

See Browncow's recent post showing the snoot, which I'm sure you are aware of.
 
BrownCowVideo said:
..

For the Alzo unit, there's a discussion going around about the fan noise from the light. I'm running a test on that today with my unit. What's the fan noise like on your RPS light?
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I have the Nicephoto unit, not the RPS. I was just mentioning the RPS because the price went down.

The Nicephoto (horrible name eh?) is 150W vs the 100watts of the Alzo and RPS. The fan is probably not ok for audio. They say 'silent fan' on their page, which is what we expect from the Chinese. Lies, lies, and more lies. It is likely louder than the Alzo or RPS since is consuming 50% more power. I haven't tried making a recording with it as you have.
 
Paul F said:
I have the Nicephoto unit, not the RPS. I was just mentioning the RPS because the price went down.
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Ah, sorry, yours is the Nicephoto. 150W is quite a light blaster, wow.

Regarding fan noise, I truly think that these units were designed with still photographers in mind (where fan noise would be irrelevant). The Westcott SkyLux unit that the Chinese are all ripping-off with these copycat LED units seems to be designed as a mono strobe replacement. And the form-factor sure resembles a strobe more than a video light. The cool, daylight-balanced, continuous WYSIWG lighting would appeal to photographers, especially for rims and backlights.
 
I agree, definately designed for photographers, not video/film. These are just too loud for critical sound recordings, the Alzo probably being the quitest amongst them for now. Now if they can get the cooling right...
 
Here are some detailed shadow shots. The light is 7' from the bottles.

This is with the reflector off. Aperture is f7.1.



This is with the reflector on. Aperture is now f11 for the same exposure.



This is with the bottle pulled away from the wall for a more diffused shadow.

 
I swapped out the NMB 35db fan for a Sanyo 22db fan. I shot some video with a Tram TR-50 lavaliere and I could not hear a difference between the light on and off.

I ran the light for 2 hours in a 70 degree room. It did not shut down. As i mentioned before, there is a temperature probe on the heatsink that I assume will shut down the unit if it gets too hot.
 
Paul F, stip, et al,

Trying to get a handle on these lights and your opinions... Are you confident in them enough, with a fan upgrade, that you'd buy these instead of Arri style fresnels?
 
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