C41
Kodak Portra 400
Kodak Portra 400 is a professional C-41 color negative film known for flexible exposure latitude, natural skin tones, and fine grain.
View profile →slr-35mm
The Pentax SF-X (1987) is Pentax's first autofocus SLR, introduced alongside the new KAF mount - the K-mount extended with autofocus electrical contacts. Sold as the **SF-X** in North America and most export markets, as the **SFX-N** or **SF-X N** in Japan, and in some markets as the **SF1**, it launched Pentax into the AF SLR segment three years after Minolta's Maxxum 7000 had set the standard. The SF-X features single-point phase-detection autofocus, full PASM exposure control, and - for the first time in any SLR - a built-in retractable pop-up flash integrated into the prism housing.
Reference
Recommended film stocks for the 35mm format your camera takes.
C41
Kodak Portra 400 is a professional C-41 color negative film known for flexible exposure latitude, natural skin tones, and fine grain.
View profile →BW
Kodak Tri-X 400 is a classic black-and-white film known for strong tonality, visible grain, and documentary character.
View profile →C41
Kodak Gold 200 is a daylight-balanced C-41 color negative film with warm color, moderate grain, and a classic consumer-film look.
Develop 35mm film
Labs in our directory that process 35mm film.
Before you buy used
About this camera
Pentax's first commercially available autofocus SLR (1987) - KAF mount launch, full PASM, and the world's first SLR with a built-in pop-up flash.
| Field | Value |
|---|
| Format | 35mm |
| Mount | Pentax KAF |
| Years | 1987-1992 |
| Shutter | 30s – 1/2000s, electronic vertical cloth |
| Flash sync | 1/100s |
| Meter | TTL center-weighted SPD |
| AF | Single-point phase detection |
| Modes | Program, Aperture-priority, Shutter-priority, Manual |
| Built-in flash | Yes (first SLR to have one) |
| Viewfinder | ~92% coverage, ~0.81x |
| Weight | ~670 g |
| Battery | 1x 2CR5 |
Minolta's Maxxum 7000 (1985) and Canon's EOS 650 (1987) had both entered the autofocus SLR market before Pentax. The SF-X arrived in 1987 and carried a significant design decision: rather than developing an entirely new lens mount (as Minolta had with the A-mount and Canon with EF), Pentax extended its existing K-mount with autofocus contacts. This KAF mount preserved backward compatibility with the entire installed base of K and KA manual-focus lenses, accepting them in manual-focus operation with full metering. The trade-off was AF speed and accuracy constrained by motor placement; early KAF AF lenses used a body-driven screwdriver coupling, requiring the lens to carry its own helicoid.
The SF-X was released simultaneously with the first KAF autofocus lenses: the FA 35-70mm f/3.5-4.5 and FA 70-210mm f/4-5.6 zooms. The built-in pop-up flash - covering approximately GN 12 at ISO 100 - was immediately influential; Canon, Nikon, and Minolta all introduced built-in flash on consumer SLRs within two years. Pentax updated the body to the SF7 (a cosmetically differentiated variant) before moving to the more capable PZ-1 in 1991.
Two claims attach to the SF-X reliably. First, it is Pentax's first commercially sold autofocus SLR, making it the entry point for the KAF system that would carry Pentax through the 1990s and into DSLR production. Second, it is the first SLR with a built-in pop-up flash - a feature so convenient it became a default on virtually every consumer SLR and DSLR made afterward.
The AF performance, judged against 2026 standards, is slow: single-point, body-driven screwdriver coupling, no predictive tracking. Contemporary reviews noted it was noticeably behind Canon EOS in autofocus speed. For static subjects and moderate action it was adequate; for sports and fast movement it required anticipation. This limitation did not prevent the SF-X from succeeding in the consumer market, where the combination of built-in flash, PASM, and K-mount backward compatibility was compelling.
For current buyers, the SF-X is primarily of interest as an entry into the Pentax KAF lens ecosystem - particularly the FA-series primes (FA 50/1.4, FA 77/1.8 Limited, FA 31/1.8 Limited) and the extensive K/M/A manual-focus back-catalog. The 1/100s flash sync is lower than ideal, and the single 2CR5 battery is expensive relative to common AA alternatives on competing bodies.
Pentax KAF mount. Autofocus operates with KAF and KAF2 lenses; older KA, K, and M lenses mount and meter in manual focus. The full FA prime lineup works with matrix metering and TTL flash on this body. SMC Pentax-A lenses work in aperture-priority and manual modes. Notable glass for this system: FA 50mm f/1.4, FA 28mm f/2.8, FA 85mm f/1.8, FA 35-80mm f/4-5.6 (kit zoom), FA 70-210mm f/4-5.6. Motor drive: the Body Motor Grip F adds a power winder. TTL flash: AF280T, AF360FGZ (check compatibility); the built-in flash covers guide number ~12 (ISO 100 meters).
BW
Ilford HP5 Plus is a flexible ISO 400 black-and-white film with classic grain and strong push-processing tolerance.
View profile →C41
Kodak Ektar 100 is a fine-grain C-41 color negative film with saturated color and high sharpness.
View profile →Pentax SF-X
Image coming soon