Jurnalul Lunetelor Simplet

  Astronomical Observation Journal  1 March – Campani Replica Singlet Objective (40 mm, 2440 mm)  Instrument Description On the evening of March 1, I conducted a new observational session using an authentic Campani-type replica objective of 40 mm diameter and 2440 mm focal length. This lens is one of the finest Campani replicas I produced during the second series of singlet objectives last year. The remainder of that series has since been sold; this is the only specimen retained for personal observational use. The instrument represents a long-focus, single-element refractor typical of late 17th-century optical practice. Eyepieces Employed: Plössl eyepieces: 25 mm, 20 mm, 17 mm Positive Keplerian eyepieces (plano-convex): 25 mm, 20 mm, 14 mm Principal Targets The Moon Jupiter Selected double stars Bright first-magnitude stars   I. Observations of Jupiter This 40 mm × 2440 mm objective is currently the longest focal length singlet I have successfully produced using pap...

Replica Campani Refractor – Willach Collection   Instrument: Campani-type singlet refractor (replica, Willach Collection) Full objective diameter: 47 mm Effective aperture employed: 29.5 mm (comparative test at 32 mm) Focal length: 1850 mm Optical configuration: Single-element objective symmetric biconvex lens (singlet), Keplerian eyepieces (plano-convex) Observing Conditions: very good     The observations were conducted under stable atmospheric conditions with satisfactory transparency. Seeing was sufficiently steady to permit reliable evaluation of diffraction patterns and planetary detail at moderate magnifications.   I. Observations of Jupiter Eyepiece: Keplerian plano-convex, 25 mm focal length Magnification: 74X Effective aperture: 29.5 mm  Jupiter was selected as the primary object of observation. At 74X, the equatorial cloud belts were easily visible. The planetary disc was well defined and stable. Chromatic aberration, inherent to a long-focus s...

Optical Evaluation and Astronomical Observation Report Singlet Refractors I. Comparative Optical Assessment of the 1300 mm Objectives Regarding the two 1300 mm focal length singlet objectives: The 25 mm aperture objective polished on felt produces diffraction-limited images when stopped to its nominal 25 mm clear aperture. The Airy disc is clean and well formed under good seeing conditions. However, when the aperture is increased to 28 mm, the image quality deteriorates. At 28 mm, three distinct diffraction spikes or rays emerge from the Airy disc, indicating residual zonal error or edge defects. At this aperture, the objective can no longer be considered diffraction limited, and the stellar image appears compromised. In contrast, the paper-polished objective performs noticeably better. It produces diffraction-limited star images at both 28 mm and 29 mm aperture. The Airy pattern remains symmetrical, without parasitic rays or significant deformation. At present, the paper-polished lens...