Console Programming

Blocking and Block Cues

In this article, On Stage Lighting addresses some common areas of difficulty for anyone trying to get to grips with programming professional lighting desks, particularly for cued theatre performances.  Going hand-in-hand with the dreaded ‘Tracking’, lighting control ‘Blocking’ and ‘Block Cues’ often confuse beginners to the world of lighting programming.  Let’s try and straighten things out a little.

Note: Theatre likes to assign multiple meanings to the same word in order to trip the unwary ‘outside’ up, but in this instance we are discussing the ‘blocking’ of attribute values in a lighting cue stack and NOT the movement of actors around the stage area.  Using and abusing tracking for concert busking is outside of the scope of this article, we’ll be concentrating on a cued show run using what is often termed a ‘theatre stack’.

In order to understanding blocking even slightly, you need some idea of what ‘tracking’ is.  There are a number of places on the internet that discuss tracking detail, plus any decent lighting control book will do likewise.  Tracking is the system in which a lighting desk records and changes between cues, rather than the absolute values of attributes (for example, dimmer levels).

Tracking is ace, or so everyone keeps telling you.  Trouble is, as a beginner, you hate it.


Why can Blocking be an issue for beginners?

Basically, blocking can be an issue for beginners because tracking is.  In my experience, learners understand about cues and  the chronology of cue stacks and then evil people with more experience reveal a horrid concept that makes their cues behave ‘wrongly’.  There is no getting away from this hurtful reality in what previously seemed like a straightforward world.  Cues break, edits ruin things, ‘the desk is broken’,  it’s all soooo wrong.  To a new learner, tracking is an enemy no matter how much others might wax lyrical that tracking is their friend.

So what happens?

In order to combat tracking, you learn a way to block attributes in cues by ensuring they have hard values activated and recorded.  You learn that, in order to get a blackout that is always a blackout, an All Dimmer @ 0 stops those pesky edits from previous cues tracking forward and spoiling the darkness.  This solves immediate problems and gives you a feeling of being back in control. Further bad experiences at difficult moments during the lighting plot take away your confidence in tracking and soon you are blocking like mad to stay on top of what you are creating.  Not only blackouts, not just top of the act or each scene but EVERYTHING.  You have created a non-tracking scenario, defeated the enemy and you are safe.

Of course, those that know tracking will know that you have also just scuppered any chance of using the benefits of a tracked cue list. They know that changes to cues will now become a pain in the proverbial.  Perhaps if we try to understand why and how we might block or not then we can see tracking as a much more benign concept.

0% or Nothing?

Part of the Tracking / Blocking key concepts is the difference between a value or ‘no value’ with an attribute.  For simplicity, we’ll mainly concentrate on dimmer levels as they are the easier to understand than the multiple complexities of automated lighting attributes.

Seeing a blackout on stage can seem comforting as you know that nothing is on; everything is at 0%.  But is it?  In pro lighting control, the output of the fixtures is not always an indicator of how the desk is handling that channel.  Is the channel ‘active’ at 0% so that at the next Record action it will be saved at 0%?  Or is the fixture just being held at 0% by the desk output?  Where does the current channel value come from? This cue?  A previous cue?

Is this blackout really a blackout?

Types of Block

Hard Block

When you start out with theatre tracking programming, you learn that to ensure you get a dimmer at 0%, you must somehow specify that value in order for it to remain consistent.  I teach beginners to ensure a blackout with an All Dimmer at 0% common before recording the DBO cue.  This is the simplest way to make keep your blackout cue consistent during edits of other cues etc.  An All Dimmer at 0 ‘activates’ the channels with hard values to be recorded and this is what I would call a Hard Block.  The hard block is a blunt tool for sophisticated programming but serves a purpose in helping learners understand the, er, value or values and it is also a good thing to be able to pull out of the bag when using a desk you aren’t familiar with and don’t have time to read up about making block cues any other way.

A hard block doesn’t have to be for blackouts, you can use the All at 0% to start off programming a state and give every dimmer a value from the start before building your look on stage. That way, edits to the previous cue won’t suddenly turn up, uninvited, to your beautiful looking stage. The trouble with the hard block is that in order to remove the value and allow values to track though your hard blocked cue, you often will have to go back into the cue and rip the values back out again and try to return the channel to the Nothing state.

Soft Block

Professional tracking consoles have the ability to tell channels to block in a more sophisticated way than a hard block.  There are usually an option to create a block cue (block the entire cue) or block certain channels and this can be quiet flexible.  The thing about a soft block is that the block does not force channel values into the cue itself, but merely flags them as being blocked.  Channels that are activated for recording exist in the usual, hard value, way but the other soft blocked channels are more ghost-like.

The benefit of soft blocking is that the blocking of the cue, or specific channels, can be reversed fairly painlessly on pro consoles and ‘unblocked’ should you wish for values to track through the cue after all.  In effect, the channel is no longer ‘flagged’ as blocked and the only hard values remain in the cue.  To clarify, if you have recorded hard values in the cue then they will likely still need to be manually removed from the cue should you decide they are no longer needed.  This brings us neatly on to…..

The dreaded @ 0

Now that you know the difference between a hard and a soft block, there is one more thing that needs to be brought to mind when programming a theatre stack.  In this scenario, a mistake is made and you mis-type or mis-hear and bring up the wrong channel (or the LD calls for the wrong ones).  Oh no, you don’t want that either all.  Make it go away.  Right, @ 0. Sorry, all sorted. Next?

In just zeroing the erroneous channel(s), they are now blackout out again and ‘gone away’ but you have actually hard blocked them into that cue.  Before you called them up, they were free to live in peace outside of the cue stack and track lazily around the place, unmolested by the output of an actual cue.  Now they are actually being forced to 0% and will stay there until they are allowed to move to a different level or roam free once again.  In the above scenario, you really needed to Undo, Release or Remove them rather actively turning them ‘off’ and recording a cue.  What about the next cue?

Release / Clear

Pro consoles activate channels using roughly similar concepts that basically flag a particular channel for recording into a cue.  What happens after that is important too.  In a programmer based desk, the values remain activated or ‘in the programmer’ until a Clear action is performed, in other desks a Release unflags channels.  Knowing what we do about hard blocking, we might see that leaving values in the programmer and recording several cues in the stack creates a hard block in each cue. Not helpful.

To add to this confusion, what we are looking at on stage may be a the resulting output from a combination of a cue stack or stacks being played back PLUS activated channels including any forced to 0%.  Conversely, a clear programmer and no stack being played back looks to the beginner like a blackout to be recorded when it is actually nothing at all. That non-blackout + tracking = expected results when it comes to playback time.

Using Block Cues

So, having spent most of this article reminding you that tracking is supposed to be good for you and yet it can create hell and how blocking can mess things up and catch you out, what about actually using tracking and block cues?  To block or not to block?

I would suggest that in a tracking and cue stack setup, at very least, the LD should go into a plotting session with an idea about which cues are to be fully blocked.  The partial blocking of cues and individual channel blocks are devices that the programmer will probably arrive at to deal with particular issues with the cue stack.   Which cues they are very much depend on the structure of the show but one way to look at it is to cast your mind forward to cue editing.

Which cues have values that would benefit from tracking forward and through other cues and which cues are very distinct and are not ‘related’ to each other?  A single cue that turns a special on, another one turns it off and underneath the scene continues?  Neither of those special cues should be fully blocked as the scene ‘backing’ remains consistent throughout.  If you fully blocked the specials cues, editing the scene backing itself would have to be done in at least three cues.  Conversely, two completely distinct scenes should probably have a blocking wall placed between them to stop edits from the first tracking into the second.

Some ideas on blocking in the cue stack:

•Top of the Show/Act – Blocking the very first cue (e.g the Preset) sets the cue stack up to behave correctly from the start.
•Top of the Scene / Main State – Stops the previous scene edits tracking forward and ruining the new scene.
•’Big’ Transition – A cue that calls for a sudden dark stage or DBO but brings in a single special would be an example to be blocked.
•Dead Black Outs – Blackouts should always be black, so they should always be blocked.

Once you have worked out what to block, you already have an idea of what won’t be blocked.  One thing to look out for when ‘looking ahead’ to cue editing is to try not to block fixtures that run throughout a scene and through multiple cues.  Maybe you have a backlight or a cyc colour that continues on, while lots of practical light props get turned on and off.  This backlight or colour is better off not being blocked so that it can be edited at it’s originating cue at a single visit.

As a theatre LD or the designer/programmer, you really need to go into a theatre plotting session with a good idea of which cues you would like to block and note this in your cue synopsis (you do have a cue synopsis, right?). This means that at every cue record, not only are the label, cue number and fade times stated, but also if the cue is to be a block cue.

Dealing with edits tracking forward is a fact of life in theatre programming. There will always be a point when you add a channel to a cue and then need to go to the next cue to fade it out again.  In short, you cannot hard or soft block your way out of everything.  However, in order to really get all the benefits of tracking and start to see it as friend rather than foe, knowing how and when to block is important.  When starting out with theatre tracking consoles, having the confidence not to return to the safety of hard blocking everything opens allows you to develop from being someone that can record a cue to becoming a lighting programmer.

How do you use block cues? Stop by and let us know in the comments section.

Image based on photo from Nic_r at Flickr

  1. Simon


    I read most of your articles, and learned a lot, really! They’re all so great!

    I’d love a whole article on Cue synopsis and how to prepare for a theatre-stacked based show, what to think of in before-hand, while at tech rehearsal etc.


Leave a Reply

Your email address will not be published.