| Problem | Possible Cause | Solution |
| Poor definition (edge sharpness) or "sawtoothing" (irregular printing edge) | Poor contact during exposure | Check vacuum |
| Underexposure | Perform Step Wedge Test | |
| Light scattering | Use dyed fabric | |
| Insufficient washout | Wash from both sides | |
| Poor buildup of emulsion | Improve coating technique | |
| Fabric too coarse | Use higher mesh count | |
| Stencil softness | Improper mixing of sensitizer | Dissolve sensitizer thoroughly, mix well with emulsion |
| Underexposure | Perform Step Wedge Test | |
| Emulsion too old | Review storage guidelines | |
| Positives "yellowed" | Use new positives | |
| Excessive hummidity | De-humidify area, increase exposure | |
| Open-area "haze" | Positives lack density | Use new positives |
| Poor contact during exposure | Check vacuum | |
| Light scattering | Use dyed fabric | |
| "Pre-exposure" of coated screen | Use safelights; store coated screens in dark | |
| Over / underexposure | Perform Step Wedge Test | |
| Insufficient washout | Check washout procedure | |
| Emulsion washes or peels away during washout | Coating not uniform | Upgrade fabric stretching and coating procedure |
| Improper mixing of sensitizer | Dissolve sensitizer thoroughly, mix well with emulsion | |
| Underexposure | Perform Step Wedge Test | |
| Improper fabric preparation | Degrease all fabric; roughen and degrease synthetics | |
| Washout temperature too high | Washout below 100o F | |
| Emulsion too old | Review storage guidelines | |
| Emulsion not dry before exposure | Dry screen sufficiently; use screen drying cabinet | |
| Excessive humidity | Increase exposure; dehumidify shop | |
| Pinholes appear after exposure and washout | Dirt and dust settling on drying emulsion | Dry in dust-free environment |
| Dirt on positive or contact glass | Wipe positives; use window cleaner on contact glass | |
| Pinholes / fisheyes appear before exposure | Improper fabric preparation | Degrease |
| Shop dirt and dust | Housecleaning overdue | |
| Wet mesh | Dry mesh | |
| Dirt and dust settling in coater or emulsion container | Cover coater and emulsion | |
| Coating stroke too fast | Slow down; turn screen 180o after each stroke | |
| Air trapped during mixing | Allow 1-hour (minimum) for de-bubbling on mixed emulsions | |
| Pinholes on-press | Poor coating procedure | Upgrade coating method |
| Underexposure | Perform Step Wedge Test | |
| Incompatible ink or washout solvent | Use solvent-resistant emulsion | |
| Washout solvent or solvent ink contain water | Avoid solvent storage in large drums (condensation) | |
| Frit / pigmented inks; rough substrate | Assuming proper coating and exposure, use more abrasion resistant emulsion such as FX88 | |
| Details remain closed after washout | Coated screen stored too long | Use freshly coated screen |
| "Pre-exposure" of coated screen | Work under safelights; store coated screens in dark | |
| Drying temperature too high | Dry below 104oF | |
| Overexposure | Perform Step Wedge Test | |
| Poor contact during exposure | Check vacuum | |
| Poor positive | Check density | |
| Light scattering | Use dyed fabric | |
| Poor light source | Use finer mesh; use faster-exposing emulsion; upgrade light source | |
| Incomplete washout | Wash very thoroughly from both sides | |
| Light source too close | Where possible, min. exposure distance should be 1.5 times image area diagonal |
