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First impressions WILLIAM OPTICS FLUOROSTAR 91mm F/5.9

April 28, 2022 by Piergiovanni Salimbeni

SUMMARY

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  • ACCESSORI IN DOTAZIONE AL KIT
  • PRICE
  • TECHNICAL CHARACTERISTICS DECLARED BY THE PARENT COMPANY
Questo pomeriggio ho avuto un primo contatto con il rifrattore apocromatico WILLIAM OPTICS FLUOROSTAR 91mm F/5.9 che mi è stato gentilmente inviato in visione da UnitronItalia.
Nei prossimi giorni cercherò di testarlo con minuziosa dovizia per preparare una video recensione che analizzerà sia le impressioni prettamente visuali che i pregi nella fotografia astronomica.

Fig.1 – Un primo piano sul tripletto apocromatico da 91mm di diametro


Come potete vedere dai particolari pubblicati, mi trovo di fronte a un prodotto di ottima qualità meccanica che si avvale di un tripletto apocromatico da 91 mm con una lunghezza focale di 540 mm.
L’esemplare che ho ricevuto vanta, inoltre, uno Strehl Ratio 0.95+, comprenderete quindi che la curiosità è tanta. Una repentina osservazione terrestre con un oculare zoom Kowa TE-11 WZ ha rilevato una qualità eccellente paragonabile se non migliore (nella nitidezza)  a quella dei piu’ blasonati spotting scope di alta fascia. Questa sera iniziero’ i test astronomici.

Fig.2- Il primo montaggio del WIlliam Optics Fluorostar 91 è avvenuto sulla montatura altazimutale AYO AOK SWISS e sul treppiede Oberwerk Made in America


ACCESSORI IN DOTAZIONE AL KIT



Attualmente è disponibile presso UnitronItalia nel seguente Kit: WILLIAM OPTICS – WOFLT91SGRP3 che comprende:  il rifrattore William Optics  FLT 91 f/5.9 – FPL-53 colore TITANIUM con FUOCHEGGIATORE 3.3 con riduttore 2, Maschera di Bahtinov integrata nel tappo, anelli per telescopio guida, barra,e borsa. INCLUSO CERTIFICATO INTERFEROMETRICO
 
Fig.3- Un primo piano sul focheggiatore ottimizzato per la fotografia con grandi formati
 

PRICE

EUR 2.599,00 IVA INCLUSA

 

TECHNICAL CHARACTERISTICS DECLARED BY THE PARENT COMPANY

Objective Tripletto apocromatico spaziato in aria
Lunghezza Focale (mm) 540
Lens diameter (mm) 91
Lens composition FPL-53
Focal aperture F/5.9
Focuser Dual Speed 3.3″ R&P
Strehl Ratio 0.95+
Photographic compatibility Full Frame DSLR / Mirrorless / CMOS / CCD
Lunghezza max min (mm) 441- 510
Peso OTA (kg) 4.165
Peso con anelli e barra (kg) 5.575Kg
Distributore ufficiale: https://www.unitronitalia.com/
Prezzo (Euro) 2.599,00
 
Piergiovanni Salimbeni
Piergiovanni Salimbeni

Piergiovanni Salimbeni - Journalist and independent tester, founder of Binomania.co.uk, with over 25 years of experience in evaluating optical and digital instruments. It offers practical reviews and personalised advice for informed purchasing choices.

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