Quick Answer
What is the Pentax AP-241?
See also: Nikon AC-2S Automatic Level
See also: David White LM800 Automatic Level
The Pentax AP-241 is a 24x automatic optical level with 2mm per km accuracy and a ±15' compensator range, designed for general construction, site grading, and elevation transfer on commercial and residential projects.
Pentax AP-241 — Complete Specs, Manual & Guide
Category: Optical Level | Brand: Pentax | Model: AP-241
The Pentax AP-241 is a rugged automatic optical level from Pentax Precision (now part of Ricoh). The AP-241 is widely used on construction sites for general layout, floor level checks, and earthwork grade verification. The 24× telescope provides clear readings at typical construction distances, and the automatic compensator establishes horizontal plane quickly after instrument setup.
Pentax AP-241 Full Specifications
| Magnification | 24× |
| Objective aperture | 35mm |
| Accuracy (standard deviation) | 2.0mm per km double run |
| Compensator type | Pendulum (magnetic damping) |
| Compensator range | ±15' |
| Field of view at 100m | 2.3m |
| Minimum focus distance | 0.5m |
| Circular level sensitivity | 8'/2mm |
| Stadia ratio | 100:1 |
| Weight | 1.5 kg |
| Tripod mount | 5/8" × 11 thread |
Included Accessories
- Carrying case — Hard shell case with foam inserts
- Sunshade — Lens shade for outdoor work
- Cleaning kit — Lens brush and cloth
Frequently Asked Questions — Pentax AP-241
Is the Pentax AP-241 still being manufactured?
Pentax Precision instruments are no longer manufactured under the Pentax brand after Ricoh's acquisition and product line restructuring. The AP-241 remains widely available as used equipment and many dealers carry it in good condition. Calibration and service is available from authorized optical instrument service centers.
What is the accuracy of the Pentax AP-241?
The AP-241 achieves 2.0mm per km double-run accuracy — standard for a general-purpose construction level. This exceeds accuracy requirements for most construction grade checking, floor levelness surveys, and earthwork elevation transfers where ±5–10mm tolerance is acceptable.
How does the AP-241 compare to the Pentax AP-281?
The AP-281 offers 28× magnification versus the AP-241's 24×, providing slightly better long-range readability. Both achieve the same 2.0mm per km accuracy specification. The AP-241 is more compact and lighter, making it preferable for frequent moves between setups.
Can the AP-241 measure horizontal distances?
Yes. The AP-241 includes stadia lines in the reticle with a 100:1 stadia ratio. Reading the upper and lower stadia hair on a leveling rod gives the horizontal distance: the difference in readings × 100 = distance in meters. This is useful for rough distance checking without EDM equipment.
Related models: Nikon AC-2S | David White LM800
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