Ilford Delta 100

Ilford Delta 100 is Ilford's fine-grain T-grain B&W film at ISO 100 — Ilford's T-grain answer to Kodak T-Max 100, with comparable grain structure but Ilford's distinctive cool-neutral tonal palette. Introduced 1992 (alongside Delta 400 and Delta 3200); currently in production (35mm + 120 + 4×5 sheet).

Key features

• ISO 100 rated; very fine T-grain (RMS comparable to T-Max 100)
• Cool-neutral tonal palette — Ilford signature; slightly cooler than Kodak T-Max 100
• Wide latitude for slow B&W (~±1½ stops)
• Better reciprocity than cubic-grain films (p ≈ 1.1 vs ~1.3 for HP5+/FP4+)
• Available in 35mm, 120, 4×5 sheet
• Compatible with most developers — DD-X (preferred for the cleanest grain), ID-11/D-76, XTOL, HC-110, Pyrocat-HD

Workflow

• Box-speed development: DD-X 1:4 at 9 min, or D-76 1:1 at 13 min, or XTOL stock at 9 min
• Push to EI 200 cleanly; EI 400 with moderate grain
• Pull to EI 64 in dilute developer
• The T-grain emulsion benefits from precise development time control more than cubic-grain films

Practical notes

• Delta 100 is the choice when you want Ilford's tonal character with finer grain than FP4 Plus provides
• For landscape and architectural work where T-grain's reciprocity advantage matters, Delta 100 outperforms FP4+
• Available in 4×5 sheet — alongside HP5+ and FP4+, Delta 100 makes Ilford's sheet B&W lineup comprehensive
• Cold storage extends shelf life

Related films

• Ilford FP4 Plus 125 — Ilford cubic-grain alternative at similar speed
• Ilford Delta 400 — Ilford T-grain sibling at higher speed
• Kodak T-Max 100 — Kodak T-grain alternative
• Fuji Neopan Acros II 100 — Fuji T-grain alternative; reciprocity champion