Longines Master Collection Moonphase vs Seiko Prospex 62MAS Modern Re-interpretation
Longines's dress watch meets Seiko's diver
Quick Verdict
The Seiko Prospex 62MAS Modern Re-interpretation ($1,000–$1,500) delivers Seiko In-House Automatic technology in the tier below the Longines Master Collection Moonphase ($2,500–$5,000). The Prospex 62MAS Modern Re-interpretation measures 40.5mm and is rated 200m (20 ATM). The Master Collection Moonphase justifies its premium with Swiss Made heritage and Automatic Caliber L899. Both represent excellent choices in the luxury watch category.
Transparency — We earn a small commission on purchases made through our Amazon links. This doesn't affect our editorial independence.
Specifications Compared
| Feature | Longines Master Collection Moonphase | Seiko Prospex 62MAS Modern Re-interpretation |
|---|---|---|
| Price | $2,500–$5,000 | $1,000–$1,500 |
| Case Size | 40mm | 40.5mm |
| Movement | Automatic Caliber L899 | Automatic 6R35 |
| Caliber Type | Automatic (ETA A31.L91 base) | Seiko In-House Automatic |
| Power Reserve | 72 Hours | 70 Hours |
| Water Resistance | 30m (3 ATM) | 200m (20 ATM) |
| Crystal | Sapphire Crystal | Sapphire |
| Case Material | Stainless Steel | Stainless Steel with Super-Hard Coating |
| Origin | Swiss Made | Made in Japan |
Category-by-Category Analysis
Design & Aesthetics
Longines's design language vs Seiko's approach
The Longines Master Collection Moonphase features a Stainless Steel case at 40mm with Sapphire Crystal protection. The Seiko Prospex 62MAS Modern Re-interpretation offers Stainless Steel with Super-Hard Coating construction at 40.5mm with Sapphire. Both represent their brand's distinct design philosophy and heritage.
Movement & Performance
Automatic Caliber L899 vs Automatic 6R35
The Master Collection Moonphase runs the Automatic Caliber L899 (Automatic (ETA A31.L91 base), 72 Hours power reserve) at 25,200 vph (3.5 Hz) frequency. The Prospex 62MAS Modern Re-interpretation uses the Automatic 6R35 (Seiko In-House Automatic, 70 Hours reserve) at 21,600 vph (3 Hz). The Master Collection Moonphase edges ahead on power reserve.
Wearability & Fit
40mm vs 40.5mm — different wrist presence
At 40mm, the Master Collection Moonphase wears more compactly on smaller wrists compared to the Prospex 62MAS Modern Re-interpretation at 40.5mm. Water resistance differs: 30m (3 ATM) vs 200m (20 ATM).
Value & Cost of Ownership
Seiko sits in the lower tier
The Longines Master Collection Moonphase sits at $2,500–$5,000 and the Seiko Prospex 62MAS Modern Re-interpretation at $1,000–$1,500. On the specs that outlast any price: the Master Collection Moonphase uses Sapphire Crystal with 72 Hours, against Sapphire and 70 Hours on the Prospex 62MAS Modern Re-interpretation. Service intervals are typically 5-7 years for both.
Water Resistance
30m (3 ATM) vs 200m (20 ATM)
The Master Collection Moonphase is rated to 30m (3 ATM) while the Prospex 62MAS Modern Re-interpretation handles 200m (20 ATM). The Prospex 62MAS Modern Re-interpretation offers superior water resistance.
Materials Face-Off
| Component | Longines Master Collection Moonphase | Seiko Prospex 62MAS Modern Re-interpretation |
|---|---|---|
| Case alloy | Stainless steel 316L (standard mid-range Swiss spec). | Seiko Caliber 6R35 |
| Crystal | Synthetic sapphire grown via Verneuil process, Mohs 9, anti-reflective coating on interior. Mohs 9 | Sapphire with anti-reflective coating on inner surface |
| Lume specification | None (dress watch by design). | Stainless steel with Seiko's "Super-Hard Coating" (Diashield) |
| Dial finishing | Barleycorn guilloché — fine textured pattern resembling barley seed heads, machine-engraved or stamped into the dial brass disc. One of horology's cl | Unidirectional rotating, anodized aluminum insert with 60-minute dive scale and lume pip at 12 |
| Hand finishing | Blued steel via thermal treatment (heat-blued) or chemical bluing process. | — |
Cost of Ownership Compared
The Seiko Prospex 62MAS Modern Re-interpretation saves you $1,490 over 5 years of ownership
Who Should Pick Which
Pick the Longines Master Collection Moonphase if…
- Weekend warriors — 72-hour power reserve means it survives two days off the wrist
- Those who prioritize scratch resistance — sapphire crystal
- Dress watch seekers who want understated elegance
Pick the Seiko Prospex 62MAS Modern Re-interpretation if…
- Enthusiasts wanting proven Swiss/Japanese quality in the $1,000–$2,000 sweet spot
- Dive watch enthusiasts — 200m water resistance is proper dive spec
- Weekend warriors — 70-hour power reserve means it survives two days off the wrist
- Those who prioritize scratch resistance — sapphire crystal
- Dive watch collectors who appreciate proper ISO-rated tool watches
Longines Master Collection Moonphase
- ETA A31 base at this price — though Longines-exclusive, the architecture is shared platform. Some buyers expect in-house at this price.
- 30m water resistance — strictly dress watch use; no swimming, no shower
- Moonphase indication is rough — like most "simple" moonphase movements, the 29.5-day approximation is imprecise vs. actual 29.53-day lunar cycle (requires ~1-day adjustment every 2.5 years)
- 3.5 Hz frequency is unusual — not as smooth as 4 Hz peers
Seiko Prospex 62MAS Modern Re-interpretation
- Chapter ring alignment QC inconsistency.
- Aluminum bezel insert (vs ceramic on Tudor / Omega).
- 6R35 accuracy varies unit-to-unit.
Our Verdict
Longines
Master Collection Moonphase
Choose the Longines Master Collection Moonphase if you prioritize Automatic (ETA A31.L91 base) engineering, Swiss Made craftsmanship, and 30m (3 ATM) water resistance. At $2,500–$5,000, it delivers Automatic Caliber L899 with 72 Hours power reserve.
Check Price on AmazonSeiko
Prospex 62MAS Modern Re-interpretation
Choose the Seiko Prospex 62MAS Modern Re-interpretation if you value Seiko In-House Automatic technology, Made in Japan heritage, and 40.5mm proportions. At $1,000–$1,500, the Automatic 6R35 with 70 Hours power reserve makes it a compelling choice.
Check Price on AmazonThe Bottom Line
The Longines Master Collection Moonphase and Seiko Prospex 62MAS Modern Re-interpretation represent two distinct approaches to fine watchmaking — the Longines bringing Swiss Made tradition while Seiko delivers Made in Japan engineering.
Frequently Asked Questions
More Comparisons
Oris Aquis vs Seiko SPB143 (62MAS)
Swiss independence meets Japanese precision diving
Frederique Constant Slimline Moonphase vs Longines Master Moonphase
Two moonphase dress watches under $5,000
Tag Heuer Carrera Chronograph vs Longines Master Collection Moonphase
Tag Heuer's chronograph meets Longines's dress watch
Explore These Watches
How This Page Was Made
Our comparisons are generated from a hand-maintained specification database and reviewed under our editorial standards. We use AI tools to assemble pages from that data. We don’t invent specs: every number traces back to the database, and when we correct an entry, the fix is applied site-wide. As an Amazon Associate, The Horologist earns from qualifying purchases.