Alpha spot 1200 gobo index

[laurencerussell2006]

Hi,

 

I currently have some Alpha Spot 1200s with custom rotating glass gobos. We index them to a certain position and record that to a preset or cue however when going back to that preset or cue later on the index isn't the same.

 

The fixtures aren't in 16bit mode due to a lack of DMX channels and no room for expansion on the desk ( a Congo Jr).

 

Is having them in 16 bit mode the only way of accurately recalling gobo index?

 

Any advice would be great!

 

Thanks!

Laurence

[fliggygeek]

How many degrees out of alignment are the gobos on average?

360 degrees / 255 DMX values = ~1.4 degrees

Hence you should theoretically be within 1.4 degrees of the index you programmed.

 

Hi,

 

I currently have some Alpha Spot 1200s with custom rotating glass gobos. We index them to a certain position and record that to a preset or cue however when going back to that preset or cue later on the index isn't the same.

 

The fixtures aren't in 16bit mode due to a lack of DMX channels and no room for expansion on the desk ( a Congo Jr).

 

Is having them in 16 bit mode the only way of accurately recalling gobo index?

 

Any advice would be great!

 

Thanks!

Laurence

 

 

 

[laurencerussell2006]

Thanks for the response, the amount varies however sometimes it can be extremely bad, sometimes even 270 degrees out?

How many degrees out of alignment are the gobos on average?

360 degrees / 255 DMX values = ~1.4 degrees

Hence you should theoretically be within 1.4 degrees of the index you programmed.

 

 

 

[Shez]

Silly question but you're sure the whole head is in the same orientation each time?

[maxjones2000]

I know it's not much help, but in my experience of the CPA 1200, the indexing isn't very reliable! I love these fixtures, but I have to say that's one of the things that lets it down…

 

As a sidenote, are you sure the Congo is recording the index position into the cue?

[fliggygeek]

That would seem to indicate that either your desk is supplying different values or the indexing system is losing its calibration. Have you checked that the indexing sensor works and is aligned properly?

Thanks for the response, the amount varies however sometimes it can be extremely bad, sometimes even 270 degrees out?

 

[Leggy]

Probably irrelevant, but do check that the gobos are mounted securely.

I have come across loose gobos rattling around in the holders before, which obviously affects the indexing.

[ianknight]

Probably irrelevant, but do check that the gobos are mounted securely.

I have come across loose gobos rattling around in the holders before, which obviously affects the indexing.

 

This was my thought on reading your post - it used to be with the venerable MAC 500 that glass gobo's were stuck in place in the rotating holder with silicone adhesive to prevent this. A couple of degrees out I could put down to a weak retaining clip but 270 degrees would suggest that something major is happening - like the whole gobo spinning in the holder.

[fliggygeek]

Or bad tension on the index belt.

Probably irrelevant, but do check that the gobos are mounted securely.

I have come across loose gobos rattling around in the holders before, which obviously affects the indexing.

 

This was my thought on reading your post - it used to be with the venerable MAC 500 that glass gobo's were stuck in place in the rotating holder with silicone adhesive to prevent this. A couple of degrees out I could put down to a weak retaining clip but 270 degrees would suggest that something major is happening - like the whole gobo spinning in the holder.