What this estimate does and does not do
This calculator gives a starting exposure estimate when changing resin print layer height. It is deliberately labelled as a heuristic because resin exposure depends on printer model, screen age, resin chemistry, pigment, temperature, lift speed, light-off delay, supports, and model geometry. Do not treat the result as a guaranteed setting. Use it to choose a test range, then run an exposure calibration print before important or paid work.
Formula used
This calculator uses a heuristic exposure scaling model. It assumes exposure changes by roughly half the percentage change in layer height, then applies temperature and resin-type adjustments.
layer factor = 1 + 0.5 × (target layer / known layer - 1)
new exposure = known exposure × layer factor × temperature factor × resin factorTemperature factors used here:
- Below 15°C: 1.30×
- 15–20°C: 1.15×
- 20–30°C: 1.00×
- Above 30°C: 0.95×
Worked example
If 2.5 seconds works well at 0.05 mm and you want to try 0.03 mm with standard resin at room temperature:
layer factor = 1 + 0.5 × (0.03 / 0.05 - 1) = 0.8
2.5 × 0.8 ≈ 2.0 secondsUse the test range as a starting bracket for a validation print.
Assumptions and warnings
- This is not a replacement for a resin validation matrix.
- Different printers, screens, resins, lift speeds, and exposure compensation settings can change results.
- Very cold resin may need warming more than it needs extra exposure.
- Clear, flexible, and tough resins often need more exposure than standard opaque resin.
Best practice
Use this to choose a starting point, then run a small calibration print before committing to a long print or expensive model.
Frequently asked questions
Is resin exposure time directly proportional to layer height?
No. Layer height affects exposure, but the relationship is not perfectly linear. This calculator uses a heuristic scaling rule to choose a starting point, not a final calibrated setting.
Why does thinner layer height usually need less exposure per layer?
A thinner layer generally requires less cure depth than a thicker layer, although printer, resin colour, pigment, temperature, and lift settings can change the final best exposure.
Do I still need an exposure calibration print?
Yes. Use this calculator to choose a starting range, then run a validation print such as a resin exposure test before printing important models.
Why does cold resin need extra caution?
Cold resin is more viscous and can flow more slowly, which can cause failures even if exposure time is increased. Warming the resin and controlling the room temperature can be more effective than exposure changes alone.