8-bit vs 32 bit grayscale

Newbie here with a newbie question.

Which is better for grayscale, an 8-bit or 32-bit board? I’m guessing an 8-bit because of the 256 grayscale scale. My 32-bit allows an S=1000 and I’m not sure this is necessarily a good thing and here’s why…

I’m thinking the wood burns the same amount within the finer granularity of 32 bit over the coarser range of 8-bit. Another words the difference in burn between S=500 thru S=600 would appear pretty much the same versus S=100 thru S=150. I’m not sure what the scaling is between 8 vs 32 bit, but you get the idea.

So I’m thinking 8-bit is better even tho my 32 bit allows more grayscale. Are my thoughts on this flawed somehow?

BTW I’m using a FoxAlien 20 Watt (wink-wink) blue (450) diode and have a 800mw UV (405) diode as well. That and a Chinese K40 that works great for cutting.

Your logic is flipped. The S value is arbitrary and can be any number you desire, it just needs to match on the laser’s firmware and in LightBurn. 255 and 1000 are commonly used ones because of binary number of bits, but it’s nothing to do with hardware, read on…

A 32 bit board in your laser means it can run faster and make better images than an 8 bit board can. I would not be able to comment on how many actual bits of DAC the various 32 bit chips used in these machines might have, but it’s reasonable to think it’s the same or higher as an 8 bit chip. If it was the same, than the faster 32 bit chip would be the desired one.

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Thanks for the reply!

I get 32 bit is definitely a better board, I’m trying to wrap my head around the difference between 256 and 1000. The scaling and increment differences are enormous.

If you want to get into more details, look up what chipset your controllers use, then find out where in the range of say 8 to 14 bit DAC they are running. Then compare those numbers. The firmware they are running might also not be able to generate pwm at the full range that the hardware makes available - that’s more of a dark science area, trying to figure that one out. I allegedly make controllers for a living so in theory I should know about this stuff.

Like I said, you can pick your own S value number, heck Smoothieware uses a range of 0-1 with some decimals. It’s completely arbitrary.

Well I certainly have a lot more to learn! Again, thanks for the reply!!