# Percentages and my brain

Hey all. Back with another weird question as always. While burning an image, i went into the move tab. In this tab, i waited for the laser to do a full stroke and go slightly past the edge of my workpiece and i clicked on the +10% until it maxed out at 200% …Now… mathematically i know what makes sense, but i guess i juat want the old “ya duh” answer I need. If i am copying at 1200mm/m with a power of 40%, is it safe to say that by maxing out at 200% that i am getting an actual 2400mm/m and 80% power? If so, the upping did nothing negative to my image, it just made it faster. There is no linear change in darkness by doing this.
I ask because if i can safely do an image at 2400mm/m id obviously cut some time off my projects. Thanks in advance.

Simple answer: maybe, probably, not exactly.

details: generally burn produced by raised temperature and that is the function of integral of power exposure. So probably you will be very close.
Details that can derail your change:

• Laser control has bandwidth and delay will produce longer travel at higher speeds, that can cause misalignment of burned strokes.

• Laser power control is close to linear but it is not exactly linear. You may have some (slight?) gamma change, that may require power tweaking.

• Mechanics/servo has limitations and you are more likely to deviate from intended trajectory at higher speeds.

• Temperature raise may have material phase change that also make temperature chanfge non-linear/proportional.

• For high relative thermal conductivity materials, effect of change in exposure time with same power integral allow different time for heat to dissipate/propagate, thus reaching different max temperature.

At the end, the best and practical way is to run test grid, filled and thin, and see if burn quality is the same, if trajectory as desires and-lead in_lead-out are well defined, no skips or shifts.

Ok that makes sense and I intend to do a grid test. This is fir the NWT white tile painted white technique. So the material would stay the same each time. When i set everything to 200% it continued to keep the gamma throughout the burn. Thank you for the reply

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