Fujinon AS 240mm f/9

Overview

The Fujinon AS 240mm f/9 is a large-format apochromatic lens from Fuji's Apochromatic Super ("AS") series — the upper tier of Fujinon's LF lens catalog, engineered for maximum color correction in a compact package. The AS 240mm is widely regarded among large-format practitioners as one of the finest 240mm LF lenses ever manufactured. Its Plasmat optical design, apochromatic glass, 336mm image circle at infinity, and notably light 430-gram weight make it a workhorse for 8×10 landscape, 4×5 portraiture and architectural work, and fine reproduction (1:1 to 1:10 ratios).^[1]

The AS designation and Fujinon LF line

"AS" in Fujinon's large-format catalog denotes Apochromatic Super — a process-oriented family tuned for maximum color correction at moderate-to-close focus distances. Fujinon's broader LF line includes:

• A — older apochromatic primes (e.g., Fujinon A 240mm f/9, the AS's predecessor)
• AS — Apochromatic Super (this lens; peak Fujinon apochromatic performance)
• NW / SW / CMW — wide-angle designs at various focal lengths
• L — long-focal-length telephoto designs with compressed flange focal length

The AS series sits at the apex of Fujinon's general-purpose LF offerings, paired with matched apochromatic glass selection and multi-coating throughout.

Plasmat optical heritage

The AS 240mm uses a 6-element, 4-group Plasmat design — the classic symmetric double-Gauss derivative that has been the foundation of general-purpose LF lenses since the 1890s. Apochromatic glass types are substituted for some elements of the base Plasmat skeleton, reducing chromatic aberration to apochromatic levels while preserving the Plasmat's characteristic distortion correction and flat field.

The symmetric design has a consequence visible in the specifications: the flange focal length (240mm) equals the focal length, which is typical of symmetric designs but contrasts with telephoto designs (which have flange focal lengths significantly shorter than their focal length — for example, Fujinon's own L 240mm f/5.6 telephoto has a flange focal length of about 170mm). This has a practical implication: the AS 240mm requires a full 240mm of bellows extension at infinity, while a telephoto 240mm can work at about 170mm of extension. Field-camera photographers with short-bellows bodies may find the telephoto easier to use at infinity, while the AS's extension lets it focus closer without running out of bellows.

Apochromatic correction — what it means

"Apochromatic" means the lens corrects chromatic aberration at three wavelengths (typically red, green, and blue focus planes coincide) rather than the two-wavelength correction of ordinary "achromatic" lenses. Practical manifestations:

• No color fringing on high-contrast edges — a common artifact on non-apochromatic lenses at wide apertures, shown as magenta/green halos around bright subjects against dark backgrounds
• No focus shift between color channels — each color focuses at the same plane, which matters for scanning workflows (particularly digital backs) and for mixed-wavelength subjects (copy work, neon signage)
• Sharper rendering under mixed-wavelength light — tungsten + daylight mixed sources, stage lighting, and other non-monochromatic scenes

For reproduction work (Fuji's original design brief), this is the entire point — document copy work and color chart imaging demand apochromatic correction. For landscape and architectural work, it manifests as "cleaner" looking detail on paper and screen, especially visible in scenes with strong tonal contrast.

Image circle specifications

The 336mm image circle figure is at infinity focus at f/22. At closer focus distances, the image circle expands: at 1:1 reproduction (subject 240mm from lens, film 240mm from lens — the apochromatic optimization point), the image circle reaches approximately 672mm, more than enough to cover 11×14 with movements.

For reproduction work and close subjects (the lens's original design brief), coverage is never a limitation. For infinity-focus landscape and architectural work, the 336mm circle is the binding specification — and it's the figure that determines what formats this lens can cover.

Format coverage matrix

At infinity focus at f/22:

Format	Film diagonal	Coverage at infinity	Movement room
4×5	153mm	Complete	Enormous (+183mm of circle beyond frame)
5×7	218mm	Complete	Generous (+118mm beyond frame)
8×10	312mm	Complete	Modest (+24mm — enough for typical tilt/rise/fall but limiting for aggressive movements)
11×14	435mm	Does not cover at infinity	—
At 1:1 reproduction	—	Covers 11×14 with movements	—

For 8×10 landscape, the Fujinon AS 240mm is a "normal" focal length (the 8×10 diagonal is about 312mm, so any lens near 312mm is "normal" on that format). For 4×5, it's a moderate telephoto (equivalent to about 72mm on 35mm format).

Copal 1 shutter — practical workflow

The AS 240mm mounts in a Copal 1 shutter — the medium LF shutter size (Copal 0 smaller, Copal 3 larger). Specifications:

• Speed range: 1 second to 1/400 second, plus Bulb (B) and Time (T)
• Aperture range: f/9 to f/90 (the minimum aperture is a legitimate working stop on LF, used for maximum depth of field and for infrared-filtered work)
• Actuation: mechanical; no battery required. Cocking lever must be set before firing
• Flash synchronization: M and X sync posts
• Weight: approximately 430 grams including the shutter

Copal shutters become mechanically sluggish with age, particularly in damp or dusty storage conditions. Service every 5–10 years (or whenever slow speeds become audibly hesitant) is standard practice. CLA (Clean-Lubricate-Adjust) service from a competent repair house runs $100–200 and restores manufacturer-spec performance.

Weight and compactness

At ~430 grams (including shutter), the AS 240mm is notably lighter than its f/5.6 competitors:

• Schneider Apo-Symmar L 240mm f/5.6: ~780g
• Rodenstock Apo-Sironar-S 240mm f/5.6: ~700g
• Nikkor-W 240mm f/5.6: ~700g

The Fujinon trades one stop of maximum aperture (f/9 vs f/5.6) for roughly half the weight. For field-camera photographers carrying a full LF kit, this is a meaningful trade: a multi-lens kit with Fujinon AS lenses weighs substantially less than an equivalent kit with Schneider Apo-Symmars.

The f/9 maximum aperture is a non-issue for landscape and architectural work at f/22 or smaller (typical LF hyperfocal settings) since the lens is stopped down anyway. For photographers who need brighter ground-glass viewing during composition (or who do close work benefitting from wider apertures), a Schneider or Rodenstock f/5.6 alternative may be preferred.

Focus theory and the Merklinger hinge rule

For practitioners applying Merklinger's hinge rule — the view-camera focus methodology where tilt angle and hinge-line position determine which portions of the scene will render sharp — the AS 240mm's symmetric Plasmat design cooperates favorably. The hinge line forms at the front nodal point of the lens, which for a symmetric Plasmat is essentially the aperture iris position. This gives predictable hinge-rule behavior for landscape work with extensive front-tilt for foreground-to-background sharpness.

Compared to telephoto designs (where the front nodal point sits outside the lens body and hinge-rule calculations require knowing the nodal point's exact position), the AS 240mm's behavior is straightforward.

See [[merklinger-focusing-the-view-camera]] and Hyperfocal Distance for the underlying focus theory.^[1]

Primary use cases

The AS 240mm's versatility per format:

• 8×10 camera: "normal" lens (312mm diagonal). Excellent for landscape, architectural, and general-purpose work. Primary LF format this lens was sized for.
• 4×5 camera: moderately long lens (~72mm 35mm-equivalent). Excellent for portraits with compressed perspective, landscapes with moderate compression, and architectural details.
• 5×7: normal lens (~218mm diagonal). Similar to 8×10 use.
• Close-up/macro work at 1:1 to 1:4 reproduction: the lens's apochromatic design is at its best; this is the original design brief

For 4×5 landscape photographers, the AS 240mm is the "walk-around long lens" — compact enough to carry, sharp enough to justify the weight, and with enough coverage to accommodate typical movement needs.

Reputation among LF photographers

The Fujinon AS 240mm f/9 is widely regarded among LF practitioners as one of the best 240mm LF lenses ever made, specifically for photographers who prioritize:

• Sharpness and color correction
• Weight and compactness
• Value (given used-market pricing below comparable Schneider/Rodenstock alternatives)

For photographers who value:

• Maximum aperture (f/5.6 vs f/9)
• Larger image circle for aggressive 8×10 movements
• Newer lens designs with current warranty

...then a Schneider Apo-Symmar L 240mm f/5.6 or Rodenstock Apo-Sironar-S 240mm f/5.6 remains preferable despite the weight and pricing penalties.

Discontinued but plentiful

Fujifilm stopped manufacturing LF lenses around 2005–2008 as part of their broader film-market retreat. The AS 240mm was never in especially high production volumes, but the used market has steady supply — typical asking prices on eBay, KEH, and Large Format Forum marketplaces:

• Excellent condition, recent CLA: $900–1200
• Good condition, shutter working: $600–900
• Fair condition or shutter needs service: $400–600

Condition factors: lens element cleanliness (fungus is disqualifying), shutter functionality (slow speeds accurate, blade return prompt), aperture blade condition (no oil on blades), and diaphragm smoothness. CLA-serviced specimens command a premium.

Comparison with LF 240mm alternatives

Lens	Max aperture	Weight	Image circle	Pricing (used)
Fujinon AS 240mm f/9 (this lens)	f/9	430g	336mm	$600–1200
Schneider Apo-Symmar L 240mm f/5.6	f/5.6	780g	382mm	$1200–2000
Rodenstock Apo-Sironar-S 240mm f/5.6	f/5.6	700g	372mm	$1400–2400
Nikkor-W 240mm f/5.6	f/5.6	700g	336mm	$800–1400
Fujinon A 240mm f/9 (predecessor)	f/9	430g	336mm	$500–900
Fujinon L 240mm f/5.6 (telephoto)	f/5.6	580g	260mm	$500–900

The AS 240mm's sweet spot: apochromatic correction matching the Schneider and Rodenstock f/5.6 alternatives, at half the weight and roughly half the price.

Scanning and print considerations

Paired with typical LF film (HP5 Plus, T-Max 400, Portra 400 in 4×5 or 8×10), the AS 240mm's apochromatic correction produces measurable resolution at the film's limiting frequency. Drum-scanned 8×10 film shot with this lens at f/16–f/32 routinely yields 300+ megapixel images with sharpness visible at any print size up to mural scale (8×10 ft and beyond). Even 4×5 drum scans approach 200 megapixels of usable detail.

For digital-back use (not common with LF but possible), the apochromatic correction shines — chromatic aberration artifacts that plague wide-open fast lenses are absent.

Related lenses and cameras

• Hyperfocal Distance — focus theory that applies to LF lens use
• Sinar P2, Sinar F2, Linhof Technika (when deepened) — LF cameras this lens pairs with
• Sibling Fujinon LF lenses (future wave): A 240mm f/9 predecessor, L 240mm f/5.6 telephoto, AS 150mm f/9 wider sibling in the same apochromatic super family