Determining the existence of point defects in print apparatuses

A method comprising:

• applying a voltage from a charging surface onto a rotatable photoconductor of a print apparatus;
• obtaining data indicative of a measurement of a charging current resulting from applying the voltage, wherein data includes sample current values corresponding to respective rotation angle positions of the photoconductor about an axis;
• filtering the sample current values;
• responsive to detecting a spike in the filtered sample current value being greater than a threshold, determining the photoconductive surface includes a point defect;
• and
• generating instruction data to instruct a recipient device to notify an operator of the presence of the point defect.

A machine-readable medium comprising instructions which, when executed by a processor, cause the processor to:

• receive data indicative of a current measurement associated with a voltage applied onto a photoconductive surface of a rotatable photoconductor of a print apparatus, wherein the data includes sample current values corresponding to respective rotation angle positions of the photoconductor about an axis;
• filtering the data;
• determine whether a spike in the filtered data is greater than a threshold amount;
• and
• responsive to determining that a spike is greater than a threshold amount, generate instruction data to cause a recipient to be alerted to the current increase.