Short answer: You need BOTH. The FD-258 card has sections for rolled prints AND flat prints. Here's how to do each correctly.
In This Guide
The Difference Explained
Rolled Fingerprints
- Motion: Roll finger from nail edge to nail edge
- Coverage: Captures entire fingerprint surface
- Location on card: Individual boxes at top
- Purpose: Full pattern for identification
Flat (Plain) Fingerprints
- Motion: Press straight down, no rolling
- Coverage: Center of fingerprint only
- Location on card: Bottom section, four fingers at once
- Purpose: Verify sequence and pattern
FD-258 Card Layout
Top Section: Rolled Prints
10 individual boxes, one for each finger:
- Right hand: Thumb, Index, Middle, Ring, Little
- Left hand: Thumb, Index, Middle, Ring, Little
- Each finger rolled separately
Bottom Section: Flat Prints
Four grouped areas:
- Left four fingers (together, flat)
- Left thumb (flat)
- Right thumb (flat)
- Right four fingers (together, flat)
How to Take Rolled Prints
The Technique
- Ink the finger - Roll on ink pad to coat
- Position - Start with finger at one nail edge
- Roll - Smooth motion across to other nail edge
- Lift - Clean lift, don't drag
Key Points
- Roll in ONE direction only
- Maintain consistent pressure
- Don't stop mid-roll
- Goal: Full nail-to-nail coverage
Common Rolled Print Problems
- Too narrow: Didn't roll far enough
- Smudged: Rolled back and forth
- Too light: Not enough ink/pressure
- Double image: Finger slipped during roll
How to Take Flat Prints
The Technique
- Ink fingers - Light coat on all four
- Position - All four fingers together
- Press - Straight down, no rolling
- Lift - Straight up
Key Points
- Keep fingers together
- Don't rock or roll
- Even pressure across all fingers
- Thumbs done separately (also flat)
Common Flat Print Problems
- Gaps: Fingers spread apart
- Smeared: Movement during press
- Partial: Not pressed firmly enough
Common Mistakes to Avoid
Mistake 1: Skipping Flat Prints
Some people only do rolled prints. The flat print section verifies the rolled prints are in correct order. Do both.
Mistake 2: Rolling the Flat Prints
Flat prints should be pressed straight down. Rolling defeats their purpose.
Mistake 3: Not Enough Coverage
Rolled prints should go nail-to-nail. A narrow print that only captures the center isn't fully rolled.
Mistake 4: Too Much Ink
Excess ink causes smudging and fills in the ridge detail. Light, even coating is better.
Which Matters More for EFT?
Both sections are important, but rolled prints carry more identification value. If you have to prioritize quality, focus on clean rolled prints. However, complete both sections for best results.
