Replacing Moving Head lamp with LED?

[georgeman]

Hi All,

 

I have been offered an old mac 600 for free as the lamp isn't striking and I wondered if anyone out there has replaced the lamp in a moving head with an led? I don't need to to be as bright as the original 600 as, if it works, it will be used in a pretty small space compared to what the 600 is designed for!

 

I have built a fair few things with high powered LED chips before but never tried to put one in a moving head so would love to hear your thoughts and see if anyone has done it before!

 

Cheers in advance!

[gyro_gearloose]

I replaced the lamps in some Clay Paky Miniscans with LEDs a few years ago. I first wrote about it here 8 years ago! Things have moved on with LEDs since then, and I’ve been keeping an eye on LED development with a view to converting some moving heads at some point.

 

Last year I put up a list of parts I was looking at to use in any potential conversion. I haven’t managed to find any fixtures to convert, and with the current situation I’ve put any such project on the back burner for now.

 

As for converting your Mac 600, there are a few issues with them that would put me off converting that particular fixture. You say you would be using the fixture in a small space, so you might need a wide beam angle depending on how much of the space you want to light. Unfortunately the standard Mac 600 lens is 25 degrees, but the frost wheels might help with that.

 

The other problem with Mac 600s is that the original discharge lamp uses a huge heatsink that gets in the way of fitting the LED and it’s own heatsink. I’m not sure how you could use the existing heatsink to cool the LED as you would need to mount the LED somewhere near to the focal point of the reflector otherwise you risk losing a lot of light output. You could remove the existing reflector and use the LED/holder/reflector optics that I mentioned in my post from last year, but fitting them in the Martin heatsink might be tricky.

 

Hope this helps.

[georgeman]

I replaced the lamps in some Clay Paky Miniscans with LEDs a few years ago. I first wrote about it here 8 years ago! Things have moved on with LEDs since then, and I've been keeping an eye on LED development with a view to converting some moving heads at some point.

 

Last year I put up a list of parts I was looking at to use in any potential conversion. I haven't managed to find any fixtures to convert, and with the current situation I've put any such project on the back burner for now.

 

As for converting your Mac 600, there are a few issues with them that would put me off converting that particular fixture. You say you would be using the fixture in a small space, so you might need a wide beam angle depending on how much of the space you want to light. Unfortunately the standard Mac 600 lens is 25 degrees, but the frost wheels might help with that.

 

The other problem with Mac 600s is that the original discharge lamp uses a huge heatsink that gets in the way of fitting the LED and it's own heatsink. I'm not sure how you could use the existing heatsink to cool the LED as you would need to mount the LED somewhere near to the focal point of the reflector otherwise you risk losing a lot of light output. You could remove the existing reflector and use the LED/holder/reflector optics that I mentioned in my post from last year, but fitting them in the Martin heatsink might be tricky.

 

Hope this helps.

 

Really interesting input thank you! I will be sure to read your original post!

 

I hadn't thought about the 600 original heatsink... that's a brain scratcher until I get the light in front of me! In terms of the beam angle, the light would be in a school theatre... so not a tiny space but it definitely doesn't need to be as bright as the original 600 as most of the rig is pretty old and dim! This is really more of a proof of concept for me so if it does work and the beam ends up being too narrow then it will just be a quirky fixture!

 

How did you find the real world light output of the LED compared to the original lamp in terms of brightness?

[georgeman]

Hey all, I've just taken the 600 apart and got all the lamp parts out... Good news is there is loads more space in there for an LED than I thought!

 

I'll keep you updated as I get the components in to do the conversion

[gyro_gearloose]

That’s good to know. Good luck with the conversion.

[Trunker]

Hey all, I've just taken the 600 apart and got all the lamp parts out... Good news is there is loads more space in there for an LED than I thought!

 

I'll keep you updated as I get the components in to do the conversion

 

Would love to see this, as I have a few 'cheaper' 575w moving head spots that I was looking at turning to LED (potentially 180w chip). Let us know if you have any luck :-)

[georgeman]

Hey all, I've just taken the 600 apart and got all the lamp parts out... Good news is there is loads more space in there for an LED than I thought!

 

I'll keep you updated as I get the components in to do the conversion

 

Would love to see this, as I have a few 'cheaper' 575w moving head spots that I was looking at turning to LED (potentially 180w chip). Let us know if you have any luck :-)

 

So far I've got everything apart and removed the ballast (electronic version) and ignitor from the head. I'm waiting on LED parts but I have some cheap 100w led chips that I'm tempted to throw in as is!

I've ordered some 200w chips that match the colour temp and CRI of the original lamps in a hops to get the best possible match for cmy mixing... how well that will go nobody knows ha!

 

The annoying thing I've found about the Mac 600 is the need to completely remove the head from the Yoke to get into the lamp housing. As I will no longer have a lamp coming in from the back my plan is to have a fan mounted in that hole to bring in air!

[IRW]

It's not something that I've particularly dug into, but, as someone who finds LED stage lamps extremely uncomfortable to look into, I do wonder if 'home-brew' LED conversions like this are particularly safe, from an optical safety/optical radiation point of view? The light sources themselves may be 'fine' as manufactured, but does this still stand when putting them behind various lens systems without the sort of testing that say, a Mac Encore, will have been through?

 

I've only quickly glanced through it, but this document seems to give a little bit of food for thought. Maybe @BigClive would be able to shed some light (boom boom!) on the subject if he swings by?

 

[timsabre]

Many LED profile fixtures are in optical risk class 2 anyway as manufactured. Definitely something to take care over - but probably safer than mucking about with discharge lamps. Edited October 12, 2020 by timsabre

[georgeman]

It's not something that I've particularly dug into, but, as someone who finds LED stage lamps extremely uncomfortable to look into, I do wonder if 'home-brew' LED conversions like this are particularly safe, from an optical safety/optical radiation point of view? The light sources themselves may be 'fine' as manufactured, but does this still stand when putting them behind various lens systems without the sort of testing that say, a Mac Encore, will have been through?

 

I've only quickly glanced through it, but this document seems to give a little bit of food for thought. Maybe @BigClive would be able to shed some light (boom boom!) on the subject if he swings by?

 

 

Interesting read. From what I understood from the document the biggest concern is the perceived risk of LED lights emitting more blue light than incandescent lamps. As the document said this was a side effect of early and poorly made LEDs but with decent units it's not an issue.

In terms of looking directly at the light, My understanding is that if you have a similar lumin output, the risk is the same as looking at an incandescent lamp. For example, a 150w led will be roughly the same as looking straight into a 600w filament... in other words, not advised!

 

What I am most interested in is the flicker effect, especially from a fast moving head light. My hope is that with the right driver, the frequency should be high enough so as to not notice anything but I am dubious... we will see when I test it!

[Gerry]

 

 

 

I've ordered some 200w chips that match the colour temp and CRI of the original lamps in a hops to get the best possible match for cmy mixing... how well that will go nobody knows ha!

 

 

Can you post a link to where you bought your 200W chips?

Cheers

Gerry

[georgeman]

 

I've ordered some 200w chips that match the colour temp and CRI of the original lamps in a hops to get the best possible match for cmy mixing... how well that will go nobody knows ha!

 

 

Can you post a link to where you bought your 200W chips?

Cheers

Gerry

 

Hi Gerry,

 

I've actually got them from Alibaba. It's a bit of a pain if you're not used to it but if you don't mind messaging some suppliers you get a good deal and can specify exactly what you want! For example the LEDs I've gone for in the first instance are 150w (not 200 as I thought), 7200k (same as the lamp in the Mac 600), and above 85 CRI (same as original lamp). I just told an LED manufacturer what I wanted and then they can supply it.

 

When you only buy one or two items the shipping costs mean you don't save much but you can at least specify exactly what you want. When it's something as light as an LED, you can ship a fair few without bumping up the shipping cost much. Drivers weigh more so add a bit to the shipping but often you can find them here in the UK

[marcel]

@georgeman I just was able to get 2 pcs MAC600 for a low price. Also was thinking to modify them for LED's. I was wondering if you ever succeeded with this modification ?

 

[david.elsbury]

9 hours ago, marcel said:

@georgeman I just was able to get 2 pcs MAC600 for a low price. Also was thinking to modify them for LED's. I was wondering if you ever succeeded with this modification ?

 

Welcome to the forum- @georgeman hasn’t been active on the forum for almost two years and this is quite an old topic.

[sunray]

6 hours ago, david.elsbury said:

Welcome to the forum- @georgeman hasn’t been active on the forum for almost two years and this is quite an old topic.

I think it may still be a sensible place to discuss the topic, especially if @georgeman did complete the project.