Which two aspects are critical when processing latent fingerprints?

The critical aspects when processing latent fingerprints include selecting the proper powder and lifting the prints. Proper selection of powder is essential because different surfaces will yield different results with specific powders; using the wrong powder can result in poor visibility or failure to develop the prints at all. For instance, certain powders are better suited for porous surfaces, while others work effectively on non-porous surfaces.

Once the print is developed, lifting it correctly is equally important because this step ensures that the print is preserved for analysis and potential comparison to known prints. Lifting techniques vary based on the type of surface and the condition of the print, requiring care and precision to avoid damaging or altering the print during the lifting process.

The other options, while relevant to crime scene processing and evidence collection, do not focus specifically on the nuanced processes necessary for effectively capturing and preserving latent fingerprints.