Hey Guys,

Ive seen in some of the other threads that there are some good graphic designers on the boards.

If someone would be kind enough to do me a favour, I need a fairly simple black and white geometric shape making up, in a format that I can print out.
It needs to be perfect, which is why im not up to the task myself.

The graphic is one circle within another, each split into 36 segments, each segment is either coloured black or white.
It will be printed at 1200dpi monochrome on to plastic transparencies, to form the basis of a rotary encoder.

It needs to be around 40mm diameter, I can provide better details and measurements when required.



Cheers
John

On it right now (just about finished actually), but just so I know, is 40mm correct? Its awfully small.

Suitable? Obviously it's not 40mm but right idea, correct? I have it at 40mm if you want that now as well.

Hey Spiderbloke, thanks for the help.
Thats really close to what I want.

I didnt include the details precisely, because I wanst sure if anyone would respond.


There only needs to be one circle within the main outline, and each circle needs 36 segments (10 degrees per segment)
The diameter of the inner circle needs to be 21mm

Yes I know its very small and very fine. Thats the smallest one im going to try. I can scale it up fairly easily.


I have attached my really bad modification of the image you made. It only has 32 segments but it sorta gives the idea.

If you could do like that (40mm at 1200dpi) with 1 pixel wide monochrome lines then that would be perfect.

I can modify it from there...


Cheers,
John

What the hell is this for mate.

Black magick!



36 eh? That's the angle (in degrees) of each point of the magickal symbol of the pentangle. Also, add the numbers within 36, i.e 1+2+3+4 and so on up to +36 and see what you come up with. As for the numbers 10 and 21, well any (in)decent Black Loodge has 10 degrees of initiation and the inner circle always has 21 members. Bloody obvious really. heheh You've been sussed out as a Satanist John! You should've just gone here instead http://www.hermeticka.com/





(n.b. joking)

Put it in a rar. Use the bitmap.
It's about as mathematically perfect as Photoshop will allow. Which is not exactly engineering CAD, but it will do.

Hey Spiderbloke I cant open the PSD but the bitmap looks pretty much perfect.
Looks like this is gonna work great. Ill put up a little explanation in a short while for those who were asking..

The psd is the original photshop file. In case you should ever need it.
And when you print the bitmap it will be at 40mm.

Sweet, ive made the modification (using the good old bucket fill tool) and its just printing now.



OK For those who were asking what the hell im doing, ive attached a scaled down, modified image and ill try to explain.


This will be printed on to clear plastic and arranged with a couple of light sensors so that for any point of rotation (segment) the inner and outer circles colour can be read (how opaque it is, to be more precise).
There are patterns alternated around the circle, (inside white outside black, inside black outside white, and both black) to give 3 unique patterns.

By watching the patterns change, we can see the magnitude and direction of any rotation of the disc.

The disc will be controling an hifi preamp. (obviously a nice shiney knob on the outside, and the 'magick' disc on the inside).

Ill take a pic when i get that far.

John

Hey spiderbloke,

I need to make a slight change to the image, if you would be kind enough to help me out.

I need another image Identical to the last one (roten.bmp) but where the other one was 2 circles, one at 21mm and one at 40mm in diameter: now I want 4 circles. One at 6mm one at 20mm, one at 30mm and one at 40mm diameters.


Cheers again,
John