What's inside a cheapo moving head disco light from ebay?

[MarkPAman]

How wide is the beam angle on these things? How big would the circle be at 4m, for instance?

[paulears]

I they are the very similar ones that come on a bar - 4 in a row, they're about 17 degrees.

[pmiller056]

There are also the '15W' ones, rebadged by many vendors, which are firmly pitched at the party/DJ end of the market. I got a (well used) pair at a price that I could afford so that I could learn about using and programming moving head lamps. Unfortunately they have both have problems in the wiring loom caused by repeated flexing and bending - I suspect this will be a common problem in any well used moving head lamp. They are readily fixable when my time is my own and not my employers... These ones use a fan cooled RGB led module and there is significant fringing of any projected gobo image. There is no visible strobing on fast moves. Again they are competently made and all the major subassemblies are easy to dismantle and swap about. The IC's that matter (motor drivers and DMX receiver) are in sockets and they are commodity parts. The fans are a bit noisy, but are much quieter once a couple of drops of oil are added to the bearings. If there are any power supply problems then I would not consider further repair because of the cost/hassle of getting a replacement PSU.

 

Peter

[Modge]

Surprised it a white light LED source with dianacronic filters, rather than a RGB LED.

 

Combining the RGB evenly so you don't get coloured fringes through a gobo is optically very hard. Much easier to have white LED with filters.

Martin have gone for white LEDs for their profiles: http://www.martin.com/en-us/product-details/mac-quantum-profile (also the 350)

[Graham NZ]

As many have said the white is far easier to get good optics from. It also makes for a brighter light if you are using for effects.

 

As to Chinese quality I feel I can speak to this with a knowledge that many here don't have. I have run factories for major manufacturers in western countries, have run a China factory and now work with several manufacturers in China. I have also been traveling to China since 1994. I have seen a huge step change in the way things are run in China. There are Chinese factories now making products for our industry that are comparable and in some cases better to factories I know in the western world. Many source management staff and engineers from the major corporate electronics companies in China.

 

Many are integrated and manufacture everything from the LEDs, have CNC machines, state of the art PCB manufacturing and very sophisticated test labs. Many western brands that are held in high esteem source many many of their components from China or other low cost countries. Ask your reps where the PCBs, metal work, lenses, LEDs, lamp holders etc are made. Most western manufacturers are simply assembly shops.

 

Not one factory I ran in the west had the following equipment:

Full Optical test lab with numerous size spheres

Full EMC lab

Full IP test facility up to IP68

Thermal Shock ovens

Vibration tables

 

The other thing I see changing rapidly is the simple copy mentality. There is an active desire to make product that is unique and has features beyond the western brands. Parts of this are driven by the major companies in the west who are sourcing products and building their brands strongly in the market. Certainly I know the company I am working for is actively developing products unique to us, it is one of the reasons I am working with them and spend so much time in China.

 

Hope that helps put some of the perceptions about China in perspective.

 

If more people took the positive path of opening products and actually looking at them and then compared them to other competitive products I am sure many people would be surprised.

 

Just remember any of you looking at this on an iPad, iPhone or many of the Android devices out there are using technology made in China.