Cold-hearted orb that rules the night

[mobident]

Here is a grayscale conundrum:

Why do we keep talking about white being the top of the board, and black as the depth of cut?
Clearly, this is opposite to reality.

For example -
The boom operator sheild that Jon Jantz helped poteetjr with - see next post's attatched jpeg, imports nicely but needs to be flipped to have the original white at the top of the board as expected.

i.e. black is the top surface and white is the depth of cut.

Thinking about this did result in an interesting piece:

I bought my machine 4 weeks ago and broke my carving bit 3 weeks ago, so only ran a few projects before left to ponder these more esoteric questions.

The peice it broke on was a chinese checker board. I used patterns that others had posted, so most of you will recognize the components.

I thought the figurine was ideal for a test run to show what the machine could do, though, like with photos, it was useless sticking out of the board. The recessed version - just as imported - seemed really cool, and would make a good well to hold game pieces. So the checkerboard was born with the idea of the piece being the top of a box, backlighting the figures with a cool fluorescent bulb.
Cut on wood planed to .75, the cut of the figurines was
.70 depth. I didn't dare try deeper (yet). It really looks better than I can make an image of...

So, the question is: can a 60's band settle the cutting depth issue? a JonJantz bluenose nickle (Hey, another trivia challenge - how much is one worth?) to the first correct answer

Bruce

[mobident]

here is the boom operator image JonJantz posted

[HandTurnedMaple]

This has been a question for a few people. In most 3D software, white is top black is bottom. In Designer it is completely reversible along as you follow the scale. It is still best, IMHO, to learn it the standard way in case you ever have to use different software. For some CW/CC is the only CNC they will ever use, and that's great. For others you may change to a more commercial machine later, and you will have to relearn greyscale in order to do it.

[Greybeard]

Hi Bruce.
I think that I, like others, have contributed to any possible confusion by coming to the software with past experience of other graphic software in which white does indeed represent the high points and black the lowest.
I suppose this in turn comes from still earlier experience with photography, where shadows mean depth, and shadows are darker not lighter.

When CW chose to use white as the deepest cut I would guess it is from seeing it as an equivalence between greatest movement of the z axis (ie the largest number of possible steps, 256) and the digital value of white.
In a lot of electromechanical systems 0 is seen as a fault condition (ie if something is wrong) the system fails safe, and doesn't do any cutting, and in the CYMK system of indicating colors, the digital value for pure black is 0.

Does that confuse the issue enough, or shall I go on ?

John

Edit.
glad to see others can type faster than me : )







John

[mobident]

John,
Go on, go on.

It mostly suprised me no one had pointed out the CW exception to the rule. I was familiar with the standard, but hadn't thought of the reasons you pose for CW to be contrary

Again, 3 weeks with nothing to carve...

Still, no answers to the trivia though!!!
Bruce

[CallNeg151]

John,
Still, no answers to the trivia though!!!
Bruce

Although red is grey and yellow, white, I think what you are trying to say that when it comes to greyscale image importation in CW, it is up to us to decide (with the Invert button) which is an illusion (inverted or not)? I don't think the Moody Blues had the CW in mind when they penned that.

Or am I completely missing the question?

[BoardSilly]

The real answer can only be truely reached however by pondering it on days of future past. And we all know that Timothy Leary's dead... no no, he's outside looking in.

*Couldn't resist.

[Greybeard]

....and then, 8 bit greyscale = 256, and 0.004"(smallest step of z axis, I think) x 256 = ~1"(max depth of cut)...


John

[Hanna]

All I got to say is thank goodness for INVERT. That has allowed my world to be turned right side up again.

You are right that the confusion comes from photography etc, and as a painter, dark definately means shadows. Trying to concieve of creating a shadow in an object using light color had me standing on my head;/ And, dark is shadow in our everyday world. It is just backwards and upside down and totally contrary to our world. Its like telling someone who has slept with their eyes closed all their life that now they have to sleep with their eyes open. Invert...what a glorious word:) Oh and Maple too.....he helped turn my world right side up again:)

[mobident]

Although red is grey and yellow, white, I think what you are trying to say that when it comes to greyscale image importation in CW, it is up to us to decide (with the Invert button) which is an illusion (inverted or not)? I don't think the Moody Blues had the CW in mind when they penned that.

Or am I completely missing the question?

We have a winner!!!! CallNeg151 shows his/her age! and of course maturity.

And the quote is (hope I remember right):


Cold-hearted orb that rules the night
Remove the color from our sight
red is gray and yellow white
But we decide which is right... and which is an illusion

and so the answer to the question "can a 60's band settle the cutting depth issue?" settle - No. leave behind-yes
Any one up for the nickle?

Bruce

[mobident]

The real answer can only be truely reached however by pondering it on days of future past. And we all know that Timothy Leary's dead... no no, he's outside looking in.

*Couldn't resist.

Nor could I

[BobHill]

If one is doing engraving type carving, then, of course white would be the "bottom" and black would be the "top" (counting the wood surface as top) and this may well have been the inital thinking when establishing Designer's natural uses. It's also a reason for INVERT, since the machine will easily do either.

Bob

[CallNeg151]

Hoody hoo!

I actually saw the Moody Blues not that long ago, some time in the late 80's, early 90's :-) Of the bands I've seen, they are the ones that probably sound the best live. With all of the editing that's possible these days, it's unusual to hear a band that sounds just as good (or better) live than they do in the studio.