Diasec face-mount & Lambda Print: the gallery technique explained

Diasec face-mount on premium acrylic glass + true silver halide Lambda Print is the technique used by museums, galleries, and fine art photographers including Andreas Gursky, Wolfgang Tillmans, and Thomas Ruff. Here is how it works, why it lasts 50-75 years, and how it compares to direct-to-acrylic, metal posters, and canvas prints.

Diasec face-mount on premium acrylic glass, combined with true silver halide Lambda Print, is the technique used by museums, art galleries, and fine art photographers. Andreas Gursky, Wolfgang Tillmans, Thomas Ruff, Hiroshi Sugimoto, and most contemporary photographers represented by Gagosian, David Zwirner, and White Cube use this exact process for their exhibition prints. Here is what it is, why it lasts 50 to 75 years, and how it compares to direct-to-acrylic prints, metal posters, and canvas.

Last updated: 12 May 2026 · Reading time: 10 minutes · Author: Olivier Cordoleani, founder of YTY (publisher of Photonumerique)

What is Lambda Print?

Lambda Print is true silver halide photographic exposure executed by a high-resolution laser, then developed in classic photographic chemistry baths. The process is the same chemistry used in darkrooms for over 150 years, but the exposure step is performed by a Durst Lambda or Océ Lightjet laser printer instead of a darkroom enlarger.

The Lambda Print process step by step

  1. A digital file is calibrated to the photo paper color space (typically Fuji Crystal DP II for color, Ilford Galerie for black and white).
  2. A Durst Lambda or Océ Lightjet machine exposes the photographic paper with red, green, and blue lasers at 200 to 400 ppi.
  3. The exposed paper is developed in classic RA-4 photographic chemistry (developer, bleach-fix, wash, dry) for approximately 10 minutes.
  4. The result is a continuous-tone photographic print — the same chemistry as a darkroom print, but with the geometric precision of digital exposure.

Lambda Print vs inkjet — the critical distinction

The most common confusion: “fine art print” sold online often means inkjet print on baryta or matte fine-art paper. That is not Lambda Print. Inkjet sprays pigment droplets on paper (or directly on acrylic, in the case of UV print). Lambda Print uses light and silver halide chemistry, not droplets.

CharacteristicLambda Print (silver halide)Inkjet print (pigment)
Image structureContinuous tone, no dotsVisible dot pattern under magnification
Black densityDmax 2.4 to 2.8 (deep blacks)Dmax 1.8 to 2.2 (less depth)
Color gamutWider than CMYK inkjetLimited by ink set (8 to 12 inks)
Color fidelityTrue photographic colorsApproximation via ink mixing
Longevity (sealed)50 to 75 years25 to 75 years depending on inks/paper
ProcessLaser exposure + chemistry bathPrint head sprays ink droplets

Who uses Lambda Print?

Lambda Print is the industry standard for fine art photography exhibition prints. It is used by:

  • Andreas Gursky — the largest auction prices ever achieved by a living photographer (his “Rhein II” sold for €3.1M in 2011) are Lambda Prints face-mounted under acrylic glass.
  • Wolfgang Tillmans, Thomas Ruff, Thomas Demand, Hiroshi Sugimoto — represented by Gagosian, David Zwirner, Sprüth Magers.
  • Conservation laboratories at the Tate Modern, MoMA, Centre Pompidou, and Stedelijk Museum for archival reproductions.
  • European TIPA-Award labs producing for galleries, interior designers, and collectors worldwide.

What is Diasec face-mount?

Diasec is a patented face-mounting technique developed in Switzerland in 1969 by Heinz Sobczyk. A photographic print is bonded face-down to a sheet of premium acrylic glass using an elastic silicone agent, then sealed onto an alu Dibond backing panel. The acrylic acts as a protective and optical “lens” over the photographic image, while the silicone absorbs thermal expansion and prevents bubbles or cracks.

The Diasec face-mount process step by step

  1. The photographic print (typically a Lambda Print on Fuji Crystal DP II paper) is laid face-up on a clean surface.
  2. A sheet of premium acrylic glass (PMMA, 4 to 6 mm thick) is prepared with a polished edge.
  3. An elastic silicone bonding agent is applied between the print and the acrylic in a vacuum lamination chamber.
  4. The print and acrylic are pressed together under vacuum for several minutes, eliminating all air bubbles.
  5. An alu Dibond backing panel (3 mm aluminum-polyethylene-aluminum composite) is bonded to the back of the print, providing dimensional rigidity.
  6. The artwork is inspected, edges polished, and a recessed aluminum subframe is integrated on the back for invisible wall mounting.

Diasec vs direct-to-acrylic — the critical distinction

Another common confusion: “UV print on acrylic” or “direct-to-acrylic” means an inkjet machine sprays ink directly on the surface of the acrylic. The ink is on the outside, exposed to scratches, fingerprints, and UV degradation. Diasec is the opposite: the photographic print is sealed beneath the acrylic. The acrylic protects the image; the image is on the inside.

CharacteristicDiasec face-mountDirect-to-acrylic (UV print)
Image positionBeneath the acrylic (sealed)On the surface of the acrylic (exposed)
Scratch resistanceExcellent — acrylic protects imagePoor — image scratches easily
UV protectionExcellent — acrylic blocks UVLimited — ink exposed
Depth effectStrong (acrylic refracts light)Minimal
CleaningDamp cloth, safeRisky — can damage ink
Longevity50 to 75 years20 to 40 years
Inner print typeLambda silver halide (typical)UV inkjet (always)

The Diasec depth effect

The most striking visual feature of a Diasec face-mount is the three-dimensional depth the acrylic produces. Light enters the acrylic, hits the photographic emulsion, and reflects back through the acrylic, creating a visible “luminescence” especially in mid-tones and bright areas. Photographs gain a quality of presence not achievable on paper, canvas, or even glass-framed prints. This is why galleries chose Diasec for major exhibitions: it makes the image feel embedded in the room rather than hanging on the wall.

Why combine Diasec + Lambda Print?

Lambda Print gives you the photographic quality — deep blacks, wide gamut, continuous tone. Diasec gives you the presentation and longevity — UV protection, scratch resistance, depth effect. Together, they form the gallery standard for exhibition prints. This is the combination used by every museum-grade photographer and every TIPA-Award lab.

QualityLambda aloneDiasec aloneLambda + Diasec
Image fidelityExcellentDepends on inner printExcellent
UV protectionVulnerableAcrylic blocks UVMaximum
Scratch resistanceBare paperHard acrylic surfaceMaximum
Color depthNativeAdds refractionEnhanced by depth effect
Longevity (years)25 to 50Depends on inner50 to 75
Used by museumsSometimesSometimesYes — standard

Comparison with other premium print methods

MethodProcessLongevityCostGallery use
Diasec + LambdaSilver halide + acrylic face-mount50 to 75 yrs€85 to €4 000Standard
Direct-to-acrylic (UV print)Inkjet on acrylic surface20 to 40 yrs€50 to €1 500Rare
Metal poster (sublimation)Heat-transferred dye on aluminum15 to 30 yrs€30 to €200Never
Canvas print (inkjet)Pigment ink on canvas20 to 50 yrs€40 to €500Rare (decorative use)
Framed C-print (paper + glass frame)Lambda + traditional frame50 to 100 yrs€150 to €3 000Common (classic)
Fine art baryta paperPigment inkjet on baryta50 to 100 yrs€100 to €2 000Common

How Photonumerique produces every artwork

Every artwork in the Photonumerique catalog is produced using the Diasec + Lambda technique by a single European TIPA-Award photo laboratory. We do not subcontract to multiple labs to ensure consistency. Here is the production chain:

  1. Source file — high-resolution digital artwork (typically 6000 × 6000 pixels or larger).
  2. Color calibration — the file is profiled to the Fuji Crystal DP II color space.
  3. Lambda exposure — a Durst Lambda machine exposes the photographic paper at 200 ppi with red, green, and blue lasers.
  4. Chemical development — the paper is processed through classic RA-4 photographic chemistry (developer, bleach-fix, stabilizer, wash) for approximately 10 minutes.
  5. Inspection — the print is inspected for color accuracy, defects, and surface integrity.
  6. Diasec face-mounting — the print is bonded face-down to 4 mm premium acrylic glass with elastic silicone, under vacuum.
  7. Dibond backing — a 3 mm alu Dibond panel (aluminum-polyethylene-aluminum composite) is bonded to the back for dimensional rigidity.
  8. Recessed aluminum subframe — a custom aluminum hanging system is integrated on the back, sized to the artwork dimensions.
  9. Final QC — every artwork is inspected for bubbles, color fidelity, edge polish, and mounting integrity before shipping.
  10. Packaging — wrapped in protective foam, boxed in custom-fitted cardboard, shipped from Europe with full insurance.

Longevity, care, and conservation

Diasec + Lambda prints are designed for 50 to 75 years of display under standard indoor conditions. To maximize longevity:

  • Avoid prolonged direct sunlight — although the acrylic blocks UV, direct sun exposure of more than 4 hours per day will reduce longevity. Indirect natural light or LED lighting is ideal.
  • Indoor environments only — designed for living rooms, offices, hotels, galleries, medical practices, restaurants. Not designed for bathrooms (humidity), kitchens with stovetops (heat and grease), or outdoor spaces.
  • Temperature and humidity — best between 18 and 24°C, with 40 to 60% relative humidity. Standard residential conditions.
  • Cleaning — damp microfiber cloth only. Never use alcohol, window cleaner, or solvents — these can micro-crack acrylic over time.
  • Hanging — the recessed aluminum subframe is compatible with any standard wall (drywall, brick, concrete) and with picture rail systems (cimaises). One wall screw is sufficient.

Frequently asked questions about Diasec + Lambda Print

What is the difference between Diasec and direct-to-acrylic printing?

Diasec face-mount bonds a photographic print beneath a sheet of acrylic glass — the image is sealed and protected by the acrylic. Direct-to-acrylic (UV print) sprays inkjet ink directly onto the surface of the acrylic — the image is exposed and vulnerable to scratches. Diasec uses silver halide photographic paper inside; direct-to-acrylic always uses UV inkjet ink outside. The two methods produce visually different results and have very different longevity (50-75 years vs 20-40 years).

Is Lambda Print better than inkjet?

For photographic images, yes. Lambda Print uses silver halide chemistry (the same as darkroom prints) which produces continuous tone, deeper blacks, and wider color gamut than CMYK inkjet. Inkjet has its place for fine art on baryta paper but cannot match the depth and fidelity of silver halide for color photography. The two methods are used by different artists for different aesthetics.

How long does a Diasec face-mount last?

A Diasec face-mount with Lambda Print inside lasts 50 to 75 years under standard indoor display conditions: normal lighting (avoiding prolonged direct sun), 18-24°C, 40-60% humidity, no exposure to chemicals or humidity. The bonding silicone is thermally stable and prevents bubbles or cracks over decades. Museum installations from the 1970s and 1980s using this technique are still in display today.

Who invented Diasec?

Diasec was patented in 1969 by Heinz Sobczyk, a Swiss specialist in photographic mounting. The technique became the standard for fine art photography exhibition prints in the 1980s and remains the gold standard today. The word “Diasec” combines “diapositive” (slide film) and “Securit” (safety glass), referring to the original use of the technique for projecting slides onto sealed acrylic.

What thickness of acrylic is used in Diasec?

Photonumerique uses 4 mm premium acrylic glass on every artwork, with a 3 mm alu Dibond backing panel. Total artwork thickness is approximately 7 mm, with a 25 mm wall offset from the recessed aluminum subframe. Some galleries use 6 mm acrylic for very large formats (above 150 cm) to maintain rigidity. Below 4 mm, the depth effect is diminished and the acrylic loses structural strength.

Is Diasec a brand or a technique?

Diasec was originally a patented brand (1969, Switzerland) but the patent has expired. The word “Diasec” is now used generically to describe any face-mount technique using elastic silicone bonding between a photographic print and acrylic glass. The original method is still considered the reference, but several European labs have refined the process over the decades. Photonumerique works with a single European TIPA-Award laboratory using the original Diasec method.

Why is acrylic glass used and not regular glass?

Premium acrylic glass (PMMA) has three properties that regular glass does not: it transmits more light (92% vs 86% for glass), it is shatter-resistant (safer to ship and handle), and it can be bonded chemically to the photographic print via silicone without breakage from thermal expansion. The optical clarity is also higher than standard glass, producing the characteristic “depth effect” of Diasec face-mounts.

Can Diasec face-mounts be repaired?

In most cases, no — Diasec face-mounts are sealed, monolithic units. If the acrylic is severely scratched, the print is damaged, or the silicone has failed (very rare with modern Diasec), the entire artwork must be reproduced. Photonumerique guarantees free replacement for manufacturing defects (bubbles, separation, warping) for the lifetime of the customer, but damage from improper handling or environmental factors is not covered.

Does Diasec protect against UV light?

Yes. Premium acrylic glass blocks approximately 92% of UV light by default, and Diasec face-mounts seal the photographic image beneath this UV-blocking layer. This is one of the main reasons Diasec is used by museums for archival display. However, prolonged direct sunlight (more than 4 hours per day) can still cause gradual fading over decades. Indirect natural light or LED lighting is recommended for maximum longevity.

What is alu Dibond and why is it used as a backing panel?

Alu Dibond is a 3-layer composite panel: aluminum, polyethylene core, aluminum. It is the industry standard for backing face-mounted photographic prints because it stays perfectly flat over decades, resists moisture and corrosion, and will not warp like wood, MDF, or paper backings. The polyethylene core provides thermal stability while the aluminum layers add rigidity. Photonumerique uses 3 mm alu Dibond on every artwork.

Why is Diasec + Lambda more expensive than metal posters or canvas prints?

Diasec + Lambda uses premium materials (Fuji Crystal DP II silver halide paper, 4 mm acrylic glass, 3 mm alu Dibond, custom aluminum subframe), a multi-step production chain (color calibration, laser exposure, chemistry development, vacuum face-mounting, panel bonding, quality control), and is produced by TIPA-Award European labs with decades of expertise. Mass-market metal posters use simple sublimation printing on aluminum sheets; canvas prints use inkjet on stretched fabric. The price difference reflects the difference in materials, process complexity, and longevity (50-75 years vs 15-30 years).

Where can I see a Diasec + Lambda print in person before buying?

Photonumerique operates a physical showroom at 3, avenue de la Magalone, 13009 Marseille, France. Walk-ins are welcome during business hours to view the full range of formats, orientations, and finishes before purchasing online. International clients can request high-resolution photo samples by email. For museum-quality references, the Diasec + Lambda technique can also be seen in any major contemporary photography exhibition (Tate Modern, Centre Pompidou, MoMA, Stedelijk).

Explore Photonumerique artworks

Every artwork in the Photonumerique catalog — 730 digital art prints across 9 collections (Sweet Masterpieces, Nightmares Unleashed, Studio Harcourt Portraits, Soothing Provence, Luxury Cars, Echoes of Surreal Angst, and more) — is produced with the Diasec + Lambda technique described on this page. Five orientations (Square, Landscape 16:9, Landscape 3:2, Portrait 3:2, Portrait 16:9), 46 size combinations, prices from €84.95 TTC.

Related reading: How Photonumerique prints are made — full materials and process · Photonumerique vs Displate — gallery-grade print or mass-market metal poster? · Our story: YTY, Olivier Cordoleani, and digital art since 1986