How many pixels per output do you run and why?

I've been looking to run pixel strip to outline the house, and have a few questions.

I understand the type of pixel & wire gauge make a difference, so these are just some rough numbers. 1024 pixels could be 34m of pixel strip with 12+ power injection points.

1) Just wondering how many pixels per output people go with?

2) I see controllers state 1024 pixels per output, is that a realistic number to use?

3) What's your decision process in when to keep extending one output, or use another output/controller?

Basically I'm looking to see if I need to/should get an additional controller.

Cheers.

There's no huge issues with going to 1000 pixels per output as long as power is taken care of. The issue with large numbers of pixels per output is the maximum number of updates per second you can do. Somewhere on either ACL or Falcon someone created a table of pixels vs updates per second. From memory you can't get 40 updates per second with 1000 pixels. It's possible that 20/s is faster than you can send data out to 1000 pixels. I'm not sure what pixel controllers do when they get data sent to them faster than they can send out to the pixels.

Whilst the controllers are built capable of handling 1000+/- pixels per output, should you encounter an issue or an output decides to fail (rare put still possible) it means that the entire length of 1000 pixels will not work. If this was on a megatree or matrix, it would no doubt be a large portion of the element not working.
Sometimes sharing the load across multiple outputs to avoid this happening isn't a bad idea, but it's not a necessity.

I had as many as 1,000 pixels per output last year. Was it a good idea... Not in my opinion. I had some issues with bad pixels on my mega tree. It was 6 outputs on F16v3 with 880 pixels per output. That was a lot of darkness when I had a bad pixel on sting one of eight... This year I plan on using f16v3 and two expansions for my mega tree. 48 outputs of 110 nodes. If a pixel dies I only have one string down rather than 8. Just because it can do 1000+ pixels per output doesn't mean its a great idea..

I generally go by whatever works.
By that I mean, if I have a run of say spiral tree's and it adds up to 300 pixels for those, that is what I use. I have one output that only controls 15 pixels as that is for a staff for my nutcracker and it is over to one side away from all the other elements.
My mega tree uses 3 outputs at around 600 pixels each.
But all of my pixels are running control only from the board and power is completely separate, so I will never overload an output.

Thanks for the replies. I figured stacking pixels to fill up an output could save buying another controller.

So the decision to use additional outputs seems to be convenience, timing, or designing for failures. Good to know.

I generally use one output per prop, or more correctly:-
less than 100 pixels and I might chain a few props.
100-340 pixels will always get there own output.
More than 340 and I break the prop up into multiple outputs.

That said it's all about how bad you think it is if that outputs fails or a pisel fails early in that outputs run. Spinners and smaller props probably won't break your show, loosing anything more than one strand on the mega tree looks terrible and is something I don't want.

At end of day it's what you can live with, balanced with what you can be bothered making, and what you can afford.

daunce said:

Thanks for the replies. I figured stacking pixels to fill up an output could save buying another controller.

So the decision to use additional outputs seems to be convenience, timing, or designing for failures. Good to know.

Click to expand...

I guess if you put it that way, then yes it depends on convenience etc. The way I see it, I have 2 falcon controllers, with no expansion boards, so that means 32 outputs. That (except the mega tree) would give me say 30 'different' props. At this stage, I cannot think of that many props to put up

I think 1000 pixels per port & power injection is a bit of a dark art, last year I was approaching the 400-600 pixels per port league and started having all sorts of weird problems with props just not lighting up at all, or flickering, or incorrect colors, .. all the usual things you experience with poor signalling or lack of power. I managed to band-aid most problems with placing controllers and power supplies closer to props and less daisy chaining of props together, so for me it's just easier to deal with a lower number of pixels per port right now

Why so many injection points for 12vdc. with 30 metres of strip then you should be able to get away with 3 injection points because if you place an injection point between 2 strips and back feed and forward feed then you have 10 metres per injection point
I have done a permanent install of strip on my house and I only have power from 2 places on the ground floor and 1 place for the second storey. I actually supply the controllers power through the strip so to also reduce places where I needed power
So not sure how you come up with 12 injection points as that is effectively injecting every 3 metres and would be real ugly to set with

Also if you are using the 12vdc strip with 3 LEDs per section then that's 10 pixels per metre, so the total pixel count for 34 metres would be 340 pixels