The Zhiyun Molus B500 is the most powerful head in a new series of bi-colour LED COB lights. The Molus series comprises four units with power ratings from 100W to 500W, taking in 200W and 300W along the way. Zhiyun is undoubtedly better known for its Crane system of gimbals for DSLR and mirrorless cameras, but it seems no one can resist the lure of the LED lighting market now that costs are dramatically reduced compared to only a few years ago. While it appears relatively easy to knock out masses of lower powered 60W and 100W heads, those in the 500W range are somewhat fewer in number, and much more expensive. This Molus B500 is interesting not only because it remains affordable despite its output, but also because it doesn’t require the bulky power packs that many other LED lights need. The company claims that thanks to a new mighty fan system Zhiyun has been able to fit the power adapter inside the head and still keep the unit small. So, we plug the light directly into the wall without any additional packs to hang on stands or to dangle from cables. 

Specification 

The Zhiyun Molus B500 is a 500W LED COB light with a variable colour temperature ranging between 2700 and 6500K.  Zhiyun says that we should expect 19200 lux at a range of 1m with the temperature set to 5500K, and 76400 lux with the supplied reflector attached. The CRI (RA) is recorded at >95 and a TLCI of >97, and Zhiyun also gives us TM-30 measurements, and indicates that the TM-30 Rf (colour fidelity) for the light is 94 on average and the TM-30 Rg (gamut index, or saturation accuracy) is 101 – so colours should be very slightly over-saturated. On the whole though, colours should be quite accurately represented. 

For the power, and considering the adapter is built-in, the head is remarkably small at 245x190x159mm, and lightweight at 2.8kg. 

The modifier mount on the front of the unit is designed to accept Bowen’s S-Type accessories. 

Handling and design

I know it isn’t important, but this light looks very cool. I really like the chrome metal cages across the fans, the blue blades of the fans and the dramatically ribbed surfaces of the housing. The housing is full of holes – more holes than plastic probably – and the whole thing looks rugged and a bit alien. Like I said, looks aren’t important, but they kinda are too. 

Its ruggedness makes it look like a big light, but in fact the body is very small – especially considering the power adapter is built in and that it outputs 500W. I think the boxy appearance is because the body forms quite even-sided cube, rather than the long cuboid shapes we might be used to.

The body is made of that sort of plastic that I’m never quite sure is strong or not. It feels brittle, but we see it so often it must be okay. I’d be nervous of dropping it, but I guess that’s a good policy with any light. The attaching mount section is also plastic, but the material here is reassuringly thick and feels well made. The main handle of the mount clamp turns to allow us to adjust the angle of the light, and pulls out so we can fold it away and turn the fitting through 360°. Connected to this mount is a locking slot for an umbrella pole of up to about 10cm in diameter. 

The power cable plugs into a fitting in the middle on the rear end of the underside of the light, and a small on/off switch is located right next to it. I rather liked this placement for the on/off switch as it’s easy to see when the light is mounted high and angled downwards  and in situations when it’s hard to see the back panel of the head. The position of this power supply plug though means the protrusion, and the cable that will be sticking out of it, rather inhibits the head when we want to angle it directly upwards – as the stand and the cable will clash. Placing it off-centre would solve this. 

The intensity and colour of the output are controlled by just two dials in conjunction with a very small display screen. The dials are large and mounted on the upper corners of the rear of the body like a pair of ears. They are each protected by cut-away plastic shields so there’s less chance we’ll turn them by accident. One dial controls the brightness in 1% increments from 1-100% when we turn it, and offers us leaps of 20% when we use the dial as a button by pressing it in. The colour temperature dial allows shifts of 100K from 2700K to 6500K, and similarly jumps to five standard temperatures when we press the dial. 

A long press of the brightness button takes us to the main menu for Bluetooth connections etc, and a long press of the colour temperature button gives us access to 13 effects with control of pulse rates and colour temperatures. 

A display panel on the rear of the head keeps us informed of what settings are in use and what options they offer. It is pretty small though and not always very easy to see when the light is mounted high on a stand. The view of this panel is also easily blocked by the rear handle of the light itself. Zhiyun makes a wired remote to go with this light, though I couldn’t get one for this review. A more universal option is the ZY Vega app, which proved to be pretty good and which connected my phone and the light in no time at all. 

The Zhiyun ZY Vega app offers great control features too, and in a format that is much easier to use then the physical dials on the light itself. The app lets us match colour temperatures using the phone’s camera and gives us access to CCT gel effects – as well as a memory to store settings that we like. The app can control multiple lights of course, and can switch them all on or off with one button. It’s worth mentioning that the app is downloadable from the official Apple and Android stores – it isn’t a direct-from-the-manufacturer’s-website kind of app. 

Performance

I’m pleased with the way this light operated during this review. I used it for quite a range of projects, from products to architectural interiors and was delighted with the power of the output and the ability it affords to adjust colour temperature without losing a huge amount of brightness. Between the 6500K and 2700K settings intensity drops from a reading of f/16 4/10th to f/11 7/10th at ISO 400 – so about 2/3rd of a stop. The daylight 5600K setting remains at f/16 4/10th while the Tungsten setting of 3200K manages f/16 on the nose – all at 2 metres, 100% power and with the supplied reflector in place. 

Colour is nicely consistent across the output range, giving us the same balance from 100% right down to 5% – and further probably, I only measured to 5%. So altering the power output doesn’t change the colour balance, which is a good thing. I needed a custom balance though to get a clean grey at 5600K as Zhiyun’s idea of 5600K doesn’t match Panasonic’s. Unlike some other modern LED lights, this unit has no green/magenta shift control, so we have to take the light as it is. I found my unit has a bit too much blue and not enough green, so without a custom white balance images turned out a touch purple looking – a combination of magenta and blue. 

In many instances this didn’t present as a problem, especially when using the light on its own. When mixed with other lights and daylight pulling the purple out of the colour mix added another small step to the image processing. I hoped I might solve the issue with a custom white balance match via the app and my phone’s camera, but that proved a little optimistic. The purple shift isn’t dramatic and it was only in really colour-critical work that it was apparent, but it is there all the same. 

The reason Zhiyun has been able to keep this head small is because it has a powerful cooling system. The system works very well so long as you keep the fans clear and allow space around the head for the intake and expulsion of the air that it needs. In practical use I found it very good and I didn’t suffer any shut downs, but in tests I had the head right up against a wall and it closed down as it couldn’t breathe. You may need to be careful using it with modifiers that requite the light to be inside the softbox. 

Powerful and effective, the fans are also quite loud when running at full pelt and really needed to be taken into consideration when placing microphones. However, while I was reviewing the light Zhiyun released new firmware which has drastically reduced the noise of the fans. They are now quiet by default and rev up a bit when the light has been running at 100% for a while – but the head is nowhere near as loud as it was, and it runs enthusiastically only for a short period. It seems to be very effective. 

Updating the firmware was really simple. You can plug the head into your computer via the USB ports and run an installation tool on your desktop, or just ask the app to do the updating. I used the app and it took about one minute to complete the process. 

Conclusion

There’s no doubt that the Zhiyun Molus B500 is a pretty powerful light, and at £700/$700 you get a lot of watts for your money when compared to other brands – in fact this seems to be about 2/3rds of the price of other similar models. For the price and the power I’d be happy to make some concessions, but there aren’t many needed. With the new firmware installed the only real downsides to the light are the slight purple tint and the small control panel. Okay there’s no DMX control possibilities, and using a phone app isn’t always convenient, but for those on a budget and needing this much power there aren’t too many other choices. It will be fine for small productions and one-person operations where we have the time to control each light via an app, and the shooter is probably dealing with lighting themselves. I’ve been impressed and, so long as the few limitations are understood, there are plenty of people who will enjoy it a great deal too. 

Zhiyun 90cm Parabolic Softbox

My Molus B500 came with Zhiyun’s 90cm Parabolic softbox, so I used it quite a lot in this review. It’s a standard sort of budget softbox that assembles in about twenty seconds as we lift the eight rods and click them into place. It comes with a honeycomb grid to fit over the front diffusion panel, and a secondary diffusion panel that clips inside the box. 

It is lightweight, quick to set-up and take down, and it only costs $150. Maybe it could do with a thicker diffuser on the front or in the middle, but I suppose Zhiyun didn’t want us to lose too much light. Users can see how they feel about the quality of light and add an extra layer if they need to. In short though it’s a decent enough choice for the money.