Screen Printing Exposure Calculator
Finally, a FREE exposure calculator for anyone to download and use! Simply download the file, print out on a transparency film, and then start calculating your proper screen exposure times! We recommend performing the exposure test on each different mesh count you use for optimal results. Also, be sure to coat all your screens in the same way for consistent burn times.
Calculating Your Exposure Time
- Approximate how long you think it will take for your screen to burn (Ex. 120 seconds)
- Take that amount of time you guessed, and multiply by 1.5 (Ex. 120 x 1.5 = 180 seconds)
- Take your new time calculated in Step 2, and divide by 10. (Ex. 180 / 10 = 18 seconds)
- Tape the calculator to screen, and cover all but the first row with thick, opaque paper.
- Expose the screen for the amount of time you came up with in Step 3.
- Move the thick, opaque paper down to where it is covering all but the first 2 rows.
- Expose the screen for the amount of time you came up with in Step 3 again.
- Continue moving the paper down and exposing until you have reached the bottom.
- Wash out the screen, allow to dry, and determine which row came out best.
- Lastly, take the number of the best row and subtract from 11. For example, if row 4 came out the best, 11-4=7, meaning row 4 got exposed a total of 7 times during the test. If you were burning in 18 second increments, the correct exposure time would be 126 seconds (18x7=126).
We understand this math can seem a little intimidating at first, but just take your time and trust the formulas.
Don't know where to start? Try plugging in these numbers to step 1 and go from there:
Pre-sensitized emulsion with 500watt halogen light.
Try starting with 8 minutes.
2 part diazo emulsion with 500watt halogen light.
Try starting with 15 minutes.
Pre-sensitized emulsion with multiple uv fluorescent bulbs.
Try starting with 3 minutes.
2 part diazo emulsion with multiple uv fluorescent bulbs.
Try starting with 6 minutes.