Rastor, Vector, Step and preportional

[vibedisco]

Forgive me for being neive but I have some new moving heads and in the DMX asignment list it describes movement as vector, rastor, step and preportional and after playing around with a cheap controller I havent yet worked out the difference between these. can anyone shed some..light

[niclights]

What are the fixtures?

[vibedisco]

What are the fixtures?

 

 

they are robe 160 xts

[KevinE]

And what is your controller please?

 

Step and Proportional relate to the way the DMX channels work on the various effects inside. In step mode, the colours (for example) will jump from one colour to another (step) as you alter the DMX value on that channel. In proportional mode, the colour will fade gradually from one to another as the value changes in proportion to the amount you give it. Some channels on the Robe have dual modes and some are fixed all through the channel.

 

I dont know what 'raster' means in the manual...my English copy doesnt mention it and I'm pretty familiar with the Robes and can't recall ever seeing a mention of it.

 

Vector and its opposite setting (tracking) are to do with the way the head moves in response to the DMX controller.

 

In vector mode, you have two 'settings' to consider; the head speed and the position. You tell the head where to move to with the pan and tilt channels (the robes are 16 bit so you can give it an additional 2 channels for pan fine and tilt fine if you want)..and then you tell it how fast to carry out that movement. If the desk moves from one scene to the next before the head has finished moving, it simply tries to move to the next new position without waiting.

 

In tracking mode, the head tries to assume the position it's been told at full speed, 'tracking' how fast the DMX controller alters the values. THerefore, in order to make the head run any slower than flat-out, you have to programme a 'fade' into the scene change so that the head will move more slowly. This has the advantage that the desk won't change to the next scene until it's finished its fade and (hopefully) the head has reached its desired position.

 

Many cheap DJ grade desks don't have programmable fade times (they're fixed on a global slider) and so vector mode is the only way of getting smooth head movements that can change their speed mid-programme.

 

Of course, most pro-desks have fully programmable fades for each scene and so tracking mode is perhaps a little easier to programme in real time.

[vibedisco]

And what is your controller please?

 

its only a cheapo transcension DMX operator 2 used for a mobile rig

 

http://www.ebdj.co.uk/shop/product_info.php?product_id=12054

[KevinE]

Right ok. Well, your Robes are nominally 9-channel and that desk is really 8 channel, (up to 16 channels per fixture can only be acheived by using the page-shift key on that desk..fiddly..)..so you'll have to engage either Mode 3 or Mode 4 on the fixtures personality menu (8-bit). You then need to go into the desk setup and make sure the Pan and Tilt are set to 8-bit not 16.

 

Mode 3 is Vector, Mode 4 is tracking. Your particular desk doesnt work well in tracking mode, it makes moving heads a bit jerky as it has a slow channel refresh rate and a global fade time...you're best in vector mode as described in my previous post.

 

Have you found out what it means by 'raster'? This is normally a term used for lasers.

[niclights]

Right ok. Well, your Robes are nominally 9-channel and that desk is really 8 channel, (up to 16 channels per fixture can only be acheived by using the page-shift key on that desk..fiddly..)..so you'll have to engage either Mode 3 or Mode 4 on the fixtures personality menu (8-bit). You then need to go into the desk setup and make sure the Pan and Tilt are set to 8-bit not 16.

Are you sure the controller doesn't work in 16-bit? If it does then there are really only 7 attributes to control. I think it is very unlikely there would be separately selectable Pan/Tilt Low.

[vibedisco]

thanks for the informative responses.

 

(I think I added in raster from my laser dealings so scrap that bit.)

 

at the moment im using mode 3

 

My goal is to have a chase for slow movements that slowely scans the venue, a main dance chase and a strobe chase thats easily selectable to match breakdowns and type of music.

 

In order to achieve this I have had to make the global fade time 0.5 seconds for each scene which is fine for the main show and strobe show but way too fast for the slow chase.

 

In order to counter this I have set just two scenes in a whole bank of 8 and set the pan/tilt much slower so it has 4 x 0.5 seconds to reach before changing. this has worked ok but its eating up the limited number of 30 banks.

 

I realise the other option is to slow down the global fade time when changing to a slow chase in order to make the slow banks more economical but this is not feasable while Djing at the same time.

 

To be able to select a certain fade time to individual banks would be really usefull

 

 

 

On a seperate issue I tried replacing the base unit fan today only to find it completely inaccessible, even more so than the stepper motors of the gobowheel. can you suggest a quick access route to replace it?)

[niclights]

As Kevin suggested there is a pan/tilt speed attribute. Try using this to control positional fades rather than the controller.

[KevinE]

there are really only 7 attributes to control

 

The desk in question does support 16 bit pan and tilt but unfortunately has fixed DMX-to-fader patches that cant be altered, meaning that when the fixture is set to 16 bit mode, it rearranges its personality attributes and pushes the dimmer/blackout channel to a ninth channel which is inconvenient on a desk with only 8 faders per page. The head movement stick is soft patched to the pan/tilt faders, it works in 'fine' with a light touch and 'coarse' with a heavier touch.

 

This desk doesnt support variable fade rates, only one global one, so even if you use mode 4 and program the speed vector in your scenes, scene dwell will still be dependent on the global fade time slider and will still change the scene even if the programmed head position hasn't been reached yet. I'm afraid that this is pretty much standard on most controllers under 80 quid...I guess nvram is still relatively pricey.

 

can you suggest a quick access route to replace it?)

 

No. Welcome to the world of Moving Head repairs ;-)