antique telescope - News - Actualités - Les Observatoires du Clain2024-03-29T05:50:01Zhttp://debeerst.ning.com/profiles/blogs/feed/tag/antique+telescope80mm Secretan +/- 1920 telescopehttp://debeerst.ning.com/profiles/blogs/95mm-secretan-1920-telescope2016-06-07T07:58:07.000Z2016-06-07T07:58:07.000ZXavierhttp://debeerst.ning.com/members/Xavier<div><img src="http://storage.ning.com/topology/rest/1.0/file/get/3314846695?profile=RESIZE_400x&width=400"></div><div><p><a target="_self" href="http://storage.ning.com/topology/rest/1.0/file/get/3314849887?profile=original"><img width="550" class="align-center" src="http://storage.ning.com/topology/rest/1.0/file/get/3314849887?profile=RESIZE_1024x1024" width="550" /></a></p>
<p><a target="_self" href="http://storage.ning.com/topology/rest/1.0/file/get/3314842465?profile=original"><img width="550" class="align-center" src="http://storage.ning.com/topology/rest/1.0/file/get/3314842465?profile=RESIZE_1024x1024" width="550" /></a></p>
</div>Early A. Bardou 4" Table mount refractorhttp://debeerst.ning.com/profiles/blogs/early-a-bardou-4-table-mount-refractor2016-06-07T07:56:09.000Z2016-06-07T07:56:09.000ZXavierhttp://debeerst.ning.com/members/Xavier<div><img src="http://storage.ning.com/topology/rest/1.0/file/get/3314846120?profile=RESIZE_400x&width=400"></div><div><p>Last weekend found in a French castle this A. Bardou 4" table mount telescope.<br />
It has the old, small stamp and an unusual tube ring with 2 large screws.<br />
<a target="_self" href="http://storage.ning.com/topology/rest/1.0/file/get/3314841093?profile=original"><img width="550" class="align-center" src="http://storage.ning.com/topology/rest/1.0/file/get/3314841093?profile=RESIZE_1024x1024" width="550" /></a><br />
The lens is in fair condition and needs to be cleaned. According to the owner it was bought in the mid 19th century.<br />
The tube needs to be cleaned.  I want polish it. Just clean it.</p>
<p style="text-align: left;"><br />
<br />
<a target="_self" href="http://storage.ning.com/topology/rest/1.0/file/get/3314842751?profile=original"><img width="550" class="align-center" src="http://storage.ning.com/topology/rest/1.0/file/get/3314842751?profile=RESIZE_1024x1024" width="550" /></a>What makes this find more interesting is the case with the accessories.  A large number of eyepieces, filters, draw tubes, zenith prism, diaphragms, finder scope and a spectroscope.</p>
<p style="text-align: left;"><a target="_self" href="http://storage.ning.com/topology/rest/1.0/file/get/3314847646?profile=original"><img width="550" class="align-center" src="http://storage.ning.com/topology/rest/1.0/file/get/3314847646?profile=RESIZE_1024x1024" width="550" /></a></p>
<p id="yui_3_15_0_1_1465285193072_2163"><span id="yui_3_15_0_1_1465285193072_2179">It also has the typical elevation and locking strut.</span></p>
<p id="yui_3_15_0_1_1465285193072_2165"><span id="yui_3_15_0_1_1465285193072_2177">Unfortunately the small brass screws to attach it are missing.</span></p>
</div>French brass telescope, Boucart, Paris, +/- 1830http://debeerst.ning.com/profiles/blogs/french-brass-telescope-boucart-paris-18302016-05-16T11:02:47.000Z2016-05-16T11:02:47.000ZXavierhttp://debeerst.ning.com/members/Xavier<div><img src="http://storage.ning.com/topology/rest/1.0/file/get/3314862723?profile=RESIZE_400x&width=400"></div><div><p><span style="font-family: verdana,geneva; font-size: small;">Lens diameter 60mm tube 65mm length 89cm.</span><br />
<span style="font-family: verdana,geneva; font-size: small;">1 terrestrial eyepiece that can be removed.</span><br />
<span style="font-family: verdana,geneva; font-size: small;">Internal focuser with one knob.</span><br />
<br />
<strong><span style="font-family: verdana,geneva; font-size: small;">History</span></strong><br />
<span style="font-family: verdana,geneva; font-size: small;">Boucart Opticien Fabricant à Paris, 35 quai de l'Horloge</span><br />
<span style="font-family: verdana,geneva; font-size: small;">Boucart started activities as optician in Paris in 1790. The company was specialized in microscopes but they also sold telescopes.</span><br />
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<span style="font-family: verdana,geneva; font-size: small;">In 1820 Boucart was taken over by Kuivert Opticien, Paris. See the inventory of the Nachet Collection, 1929</span><br />
<span style="font-family: verdana,geneva; font-size: small;">Boucart isn't longer mentioned in the catalog of "L'industrie Française des Instruments de Précision" from 1901 - 1902</span></p>
<p><span style="font-family: verdana,geneva; font-size: small;">More information on the <a href="http://www.anamorfose.be/-c-167/french-brass-telescope-boucart-paris-1830" target="_blank">Anamorfose website</a><br /></span></p>
</div>Steinheil, large zenith prism, refractor telescope, +/-1880http://debeerst.ning.com/profiles/blogs/steinheil-large-zenith-prism-refractor-telescope-18802016-05-16T10:08:43.000Z2016-05-16T10:08:43.000ZXavierhttp://debeerst.ning.com/members/Xavier<div><img src="http://storage.ning.com/topology/rest/1.0/file/get/3314862983?profile=RESIZE_400x&width=400"></div><div><p><font face="Verdana">Rare Steinheil large zenith prism for refractors.<br />
Steinheil was one of the most famous European telescope brands from the 19th century.<br />
<br />
The zenith prism is a rare accessory.  Also the size is rare.  It's probably made for the large professional refractors.</font></p>
<p><font face="Verdana">More information on the <a href="http://www.anamorfose.be/-c-167/steinheil-large-zenith-prism-refractor-telescope-1880" target="_blank">Anamorfose website</a></font></p>
</div>Secretan 10cm large table top telescope +/- 1850http://debeerst.ning.com/profiles/blogs/secretan-10cm-large-table-top-telescope-18502016-05-16T09:55:23.000Z2016-05-16T09:55:23.000ZXavierhttp://debeerst.ning.com/members/Xavier<div><img src="http://storage.ning.com/topology/rest/1.0/file/get/3314860067?profile=RESIZE_400x&width=400"></div><div><p><span style="font-family: verdana,geneva; font-size: small;"><strong>Secretan 10cm large table top telescope +/- 1850</strong></span></p>
<p><span style="font-family: verdana,geneva; font-size: small;">Early (+/-1855) 10cm (!) Secretan table top telescope with all the eyepieces and finder scope.<br />
the scope has a very beautiful dark varnish. No cleaning needed. Will leave it as it is.</span></p>
<p><span style="font-family: verdana,geneva; font-size: small;">19th century table top telescopes have normally a diameter of 60mm or 75mm.  Larger models are very rare.<br /></span></p>
<p><span style="font-family: verdana,geneva; font-size: small;">A very nice example of the classic French terrestrial and astronomical refracting telescope, here in a perfect original condition with all original lacquer entirely preserved and in original wood case.</span></p>
<p><span style="font-size: small; font-family: verdana,geneva;">Comes with a rare finder scope</span></p>
<p><span style="font-size: small; font-family: verdana,geneva;">Secretan, Marc Francois Louis<strong><br /></strong></span><br />
<span style="font-size: small; font-family: verdana,geneva;">Nationality:  Swiss</span></p>
<p><span style="font-size: small; font-family: verdana,geneva;">Brief Bio:  1804-1867, mathematician; scientific instrument maker, Swiss</span></p>
<p><span style="font-size: small; font-family: verdana,geneva;">until 1844 - professor of mathematics at Academy of Lausanne;</span><br />
<span style="font-size: small; font-family: verdana,geneva;">1840 - worked with Friedrich von Martens and Samuel Heer producing daguerreotypes;</span><br />
<span style="font-size: small; font-family: verdana,geneva;">1844 - moved to Paris;</span><br />
<span style="font-size: small; font-family: verdana,geneva;">1845 - partnership with Lerebours as Lerebours & Secretan; used joint name until 1880s and beyond.</span><br />
<span style="font-size: small; font-family: verdana,geneva;">1855 - after retirement of Noel Paymal Lerebours became sole proprietor of Lerebours and Secretan, and signed himself as "Maison Lerebours et Secretan / Secretan, Successeur" and as "Opticien de S.A.M. l'Empereur." He also did work for the Paris observatory.</span><br />
<span style="font-size: small; font-family: verdana,geneva;">after 1860 - Secretan also issued catalogs as sole proprietor after 1860</span><br />
<span style="font-size: small; font-family: verdana,geneva;">Collaborated with William Eichens, designer of telescopes.</span><br />
<span style="font-size: small; font-family: verdana,geneva;">1860s - worked with Foucault, improved silvering techniques.</span><br />
<span style="font-size: small; font-family: verdana,geneva;">1867 - succeded by his son, Auguste Secretan (1833-1874) and nephew, Georges Secretan (1837-1906 )</span><br />
<span style="font-size: small; font-family: verdana,geneva;">1874 - succeded by his cousin, Georges.</span><br />
<span style="font-size: small; font-family: verdana,geneva;">c. 1900 - succeded by Paul Victor Secretan</span></p>
<p><span style="font-size: small; font-family: verdana,geneva;">More information on the <a href="http://www.anamorfose.be/-c-167/secretan-10cm-large-table-top-telescope-1850" target="_blank">Anamorfose website</a></span></p>
</div>Meopta 5,5cm table top telescope, school telescopehttp://debeerst.ning.com/profiles/blogs/meopta-5-5cm-table-top-telescope-school-telescope2016-05-16T09:53:42.000Z2016-05-16T09:53:42.000ZXavierhttp://debeerst.ning.com/members/Xavier<div><img src="http://storage.ning.com/topology/rest/1.0/file/get/3314858555?profile=RESIZE_400x&width=400"></div><div><p><span style="font-family: verdana,geneva; font-size: small;">School telescopes were a tradition in Germany in the 1920's.  In Eastern-Europe several telescope makers continued to make them after the 1950's.</span></p>
<p><span style="font-family: verdana,geneva; font-size: small;">I didn't know of Meopta making such school telescopes.  Couldn't find any information about this scopes.</span></p>
<p><span style="font-family: verdana,geneva; font-size: small;">Meopta is still known for excellent optics.  Tested the school telescope and the optics are sharp and very good contrast. </span></p>
<p><span style="font-family: verdana,geneva; font-size: small;">The mount is very solid.</span></p>
<p><span style="font-family: verdana,geneva; font-size: small;">More information on the <a href="http://www.anamorfose.be/-c-167/meopta-5-5cm-table-top-telescope-school-telescope" target="_blank">Anamorfose website</a></span></p>
</div>Antique ship deck telescopehttp://debeerst.ning.com/profiles/blogs/antique-ship-deck-telescope2016-05-16T09:51:59.000Z2016-05-16T09:51:59.000ZXavierhttp://debeerst.ning.com/members/Xavier<div><img src="http://storage.ning.com/topology/rest/1.0/file/get/3314861078?profile=RESIZE_400x&width=400"></div><div><p><span style="font-family: verdana,geneva; font-size: small;">This is a vintage marine telescope, not a contemporary copy.</span></p>
<p><span style="font-family: verdana,geneva; font-size: small;">Originally the telescope was mounted on the railing on the deck of a ship. </span></p>
<p><span style="font-family: verdana,geneva; font-size: small;">It's a very heavy instrument with excellent optics.  The views are realy spectacular.  Crisp sharp with a good contrast.</span></p>
<p><span style="font-family: verdana,geneva; font-size: small;">The telescope has a fixed eyepiece with a large eye relief.  Focusing is very smooth.</span></p>
<p><span style="font-family: verdana,geneva; font-size: small;">The telescope was probably made between 1900 and 1920.</span></p>
<p><span style="font-family: verdana,geneva; font-size: small;">More information on the <a href="http://www.anamorfose.be/-c-167/antique-ship-deck-telescope" target="_blank">Anamorfose website</a></span></p>
</div>E. Ducretet, Pyrometer, +/- 1900http://debeerst.ning.com/profiles/blogs/e-ducretet-pyrometer-19002016-05-16T09:46:02.000Z2016-05-16T09:46:02.000ZXavierhttp://debeerst.ning.com/members/Xavier<div><img src="http://storage.ning.com/topology/rest/1.0/file/get/3314860625?profile=RESIZE_400x&width=400"></div><div><p><span style="font-family: verdana,geneva; font-size: small;">A pyrometer is a device to the remote temperature-so without contact-to measure. The functioning of the pyrometer based on Wien's displacement law.</span><br />
<br />
<span style="font-family: verdana,geneva; font-size: small;">The pyrometer measures the wavelength in the infrared or visible light in which an object gives off most radiation to determine its temperature.</span><br />
<br />
<span style="font-family: verdana,geneva; font-size: small;">This device was created and marked by Eugène Ducretet in Paris around 1900. The item is in good working condition and is finished in brass with its original paint. Length of this object is 24.5 cm.</span> <span style="font-family: verdana,geneva; font-size: small;">Eugène Adrien Ducretet (November 27, 1844 -1915) was a French scientific instrument manufacturer, who performed some of the first experiments on wireless telegraphy (radio communication) in France.  He never completed a formal education, leaving primary school at age 15. After several years apprenticed to Paris engineer Paul-Gustav Froment, Ducretet opened his own workshop in 1864 at 21 Rue des Ursulines where with a few employees he manufactured classical physics research, teaching and demonstration apparatus, such as galvanometers, Wimshurst machines, and Crookes tubes. Over time his reputation grew and he became instrument supplier to several large Paris educational and scientific institutions. He was awarded a gold medal for his quality instruments at the 1878 Paris Universal Exposition and from then on his firm was a regular presence at important international expositions, winning another gold at the 1881 International Electricity Exposition in Paris. He was made a Knight of the Legion of Honour in 1885.</span></p>
<p></p>
<p><span style="font-family: verdana,geneva; font-size: small;">More information on the <a href="http://www.anamorfose.be/anamorfose-curiosa/wetenschappelijke-objecten/e-ducretet-pyrometer-1900" target="_blank">Anamorfose website</a></span></p>
</div>Direct vision antique spectroscopehttp://debeerst.ning.com/profiles/blogs/direct-vision-antique-spectroscope2016-05-16T09:43:20.000Z2016-05-16T09:43:20.000ZXavierhttp://debeerst.ning.com/members/Xavier<div><img src="http://storage.ning.com/topology/rest/1.0/file/get/3314860975?profile=RESIZE_400x&width=400"></div><div><p><span style="font-family: verdana,geneva; font-size: small;">Beautiful direct vision antique spectroscope. The spectroscope works very well.</span></p>
<p><span style="font-family: verdana,geneva; font-size: small;">Is a large and heavy instrument.</span></p>
<p><span style="font-family: verdana,geneva; font-size: small;">Probably made around 1900.</span></p>
<p><span style="font-family: verdana,geneva; font-size: small;">The split mechanism is in brass and in perfect working condition.  Inside the tube is the prism system.</span></p>
<p><span style="font-family: verdana,geneva; font-size: small;">The spectroscope has a filar eyepiece.</span></p>
<p><span style="font-family: verdana,geneva; font-size: small;">More information on the <a href="http://www.anamorfose.be/anamorfose-curiosa/wetenschappelijke-objecten/direct-vision-antique-spectroscope" target="_blank">Anamorfose website</a></span></p>
</div>ATOS updatehttp://debeerst.ning.com/profiles/blogs/atos-update2016-03-23T23:08:39.000Z2016-03-23T23:08:39.000ZXavierhttp://debeerst.ning.com/members/Xavier<div><img src="http://storage.ning.com/topology/rest/1.0/file/get/3314858794?profile=RESIZE_400x&width=400"></div><div><p>The ATOS project becomes a Turtle project (my totem sign).  Slowly advancing but with a lot of perseverance like a turtle.</p>
<p>About every 3 weeks I travel to the Provence in search of the right spot for the observatories and the overnight stays for the visitors.  Every time I leave with  an agenda with about 7 or 8 appointments for visiting different places.  The selections of the sites starts behind my computer: searching for the right ads, contacting the sellers, gathering all the needed information, checking if the location is situated in a dark area, etc.</p>
<p>Then leaving for a trip of about 3.000km.  Meeting a lot of interesting people and visiting the most beautiful places.  I learn a lot about the local life.<br />
I still have a feel good in this region.  Every time I feel more at home in the Provence.  I don't feel as a tourist or occasional visitor but more as a prospector in search of the right valuable source.</p>
<p>As a result of the visits I start to build a local network of friends and other people who help us.  (Special thanks to Jean-Luc, Caroline and Erik).</p>
<p>A problem with the different sites is meanly the organisation of the domain: not enough free space for the observatories, bad condition of the buildings, an inappropriate price or not suited for visitors.<br />
But the main problem is obtaining the building permit for the observatories.  Most of the dark location are part of a natural reserve and it's very difficult or almost impossible to obtain a building permit for the observatories. Certainly for observatories with domes.  So the observatories will be "simple" roll-off roof observatories.  This observatories look like garden sheds.  This kind of observatories can very well be integrated in the landscape.</p>
<p>For locating the dark areas in the Provence I use a detailed <a href="http://www.lightpollutionmap.info/#zoom=4&lat=5759860&lon=1619364&layers=B0TFFFFTT" target="_blank">light pollution map</a>.  On site the Sky Quality Meter is my most important instrument.  A sky of minimum 21.5 mag/arcsec² is a base.</p>
<p>Meanwhile our house in Belgium is <a href="http://debeerst.ning.com/huis-te-koop-izegem" target="_self">for sale</a>.  An important step in the project. <br />
The whole family will be moving to France.  This means also looking for schools for my kids.</p>
<p>The work at the classic telescopes continues.  The 12" Cassegrain is ready.<br />
Continue to restore the focusers and other accessories.  It 's to cold in the warehouse to work at the large scopes.  Within a couple of weeks the works will start again in the warehouse.</p>
<p>To be continued</p>
<p></p>
<p></p>
<p></p>
</div>Nice German Scopehttp://debeerst.ning.com/profiles/blogs/nice-german-scope2016-02-27T20:47:21.000Z2016-02-27T20:47:21.000ZXavierhttp://debeerst.ning.com/members/Xavier<div><img src="http://storage.ning.com/topology/rest/1.0/file/get/3314860570?profile=RESIZE_400x&width=400"></div><div><p>New find. 90mm f1170mm refractor on altaz fork mount.<br />
The lens is extremely good. Sharp and good contrast. The lens has no coating. Must be made between 1900 and 1914. No indication of a brand.<br />
Original wooden box for the telescope and mount.</p>
<p><a target="_self" href="http://storage.ning.com/topology/rest/1.0/file/get/3314862114?profile=original"><img width="300" class="align-center" src="http://storage.ning.com/topology/rest/1.0/file/get/3314862114?profile=RESIZE_320x320" width="300" /></a><a target="_self" href="http://storage.ning.com/topology/rest/1.0/file/get/3314860656?profile=original"><img width="300" class="align-center" src="http://storage.ning.com/topology/rest/1.0/file/get/3314860656?profile=RESIZE_320x320" width="300" /></a> <a target="_self" href="http://storage.ning.com/topology/rest/1.0/file/get/3314861128?profile=original"><img width="300" class="align-center" src="http://storage.ning.com/topology/rest/1.0/file/get/3314861128?profile=RESIZE_320x320" width="300" /></a></p>
<p>The eyepiece has a strange diameter: 22mm. No standard diameter</p>
<p><a target="_self" href="http://storage.ning.com/topology/rest/1.0/file/get/3314862674?profile=original"><img width="300" class="align-center" src="http://storage.ning.com/topology/rest/1.0/file/get/3314862674?profile=RESIZE_320x320" width="300" /></a><a target="_self" href="http://storage.ning.com/topology/rest/1.0/file/get/3314861312?profile=original"><img width="300" class="align-center" src="http://storage.ning.com/topology/rest/1.0/file/get/3314861312?profile=RESIZE_320x320" width="300" /></a><a target="_self" href="http://storage.ning.com/topology/rest/1.0/file/get/3314860570?profile=original"><img width="300" class="align-center" src="http://storage.ning.com/topology/rest/1.0/file/get/3314860570?profile=RESIZE_320x320" width="300" /></a></p>
<p>The central colon of the mount be raised.<br />
The mount and tripod are very stable.<br />
The telescope, mount and tripod have been repainted by a former user.</p>
</div>About the restoration of a classic Merz refractorhttp://debeerst.ning.com/profiles/blogs/about-the-restoration-of-a-classic-merz-refractor2015-09-09T12:21:04.000Z2015-09-09T12:21:04.000ZXavierhttp://debeerst.ning.com/members/Xavier<div><p><iframe width="560" height="315" src="https://www.youtube.com/embed/OXz7ruLpXJU?rel=0" frameborder="0" allowfullscreen=""></iframe></p>
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