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Posts Made By: Ron Oehlert

May 6, 2010 08:33 PM Forum: Equipment Talk

help with building the no can dew buster controlle

Posted By Ron Oehlert

When you say unsucessful, does it not eliminate dew formation? These devices are Not hand warmers. Your pic is unclear on my pc with some connections & print unreadable plus I cannot discern heater element conection, so I cannot comment on the schematic. You do know that the circut Common return is to be connected to power Negative? Suggested contruction methods would be to use a socket for the IC rather than soldering direct to IC; some IC's are static sensitive & require special handling procedures with a Ground lead attached to the handlers' wrist. If you have hand soldered direct to IC, it is probably dead. Leave transistor & diode leads long & apply heat sinks when soldering to them (arrange sinks so that heat is drawn Away from device rather than towards it). Leave all part leads long & Do Not snip leads short until After soldering.

May 7, 2010 08:51 PM Forum: Refractors

Anti-fringe filter vs stopping down an achromat

Posted By Ron Oehlert

What has been Your experience? Or do you ask because you have no filter to trial & compare? With a 6" f/8 reflector, I found that full aperture despite a turned-down edge revealed much more lunar & planetary detail not to mention deep sky light grasp than when stopped to 5" (eliminating the turned edge effect). I preferred a degraded 6" to a perfect 5". IOW aperture trumps all else, so if you have no filter, get one. Or two or three, other colors are also effective (such as Yellow or Orange). Colored celephane or photographic gelatin filters cut & mounted in slide frames are inexpensive & may be hand held between eye & eyepiece. I find no good reason to stop down my 80mm achromat refractor & the turned edge of the 6" reflector has been corrected.

May 13, 2010 03:45 PM Forum: Equipment Talk

What's the difference

Posted By Ron Oehlert

A German type is just one of several types of Equatorial mounts. Any mount that tracks in Right Ascension is known as Equatorial. An equatorial mount that uses a counterweight on the Declination axis to balance its' scope position off-set to the polar axis is known as a German type design. SCT Fork mounts when aligned on the pole star via a base wedge are also Equatorial. The 200-inch Mt Palomar scope uses a Horseshoe-type equatorial mounting. The differances in your Program may have to do with the Central Meridian, or all-sky accessability issues as a German Equatorial may need to be reversed on its' Declination Axis when traversing through & past the Central Meridian. BTW, Notice the spelling: equAtorial (not equItorial) refers to the Earths' Equator & thus also the Equator of the Celestial Sphere along which Right Ascention is delineated.

May 16, 2010 08:38 PM Forum: Astro Binoculars

Reflecting mirror for binoculars?

Posted By Ron Oehlert

If the info you previously accessed still exists on the www, you Do Not neccessarily require a hyperlink address; you Do need to initiate a few self-Searches per subject matter via google dot com. I never Bookmark anything anymore as the Search function is so quick & unclutters my pc.

May 19, 2010 10:57 PM Forum: Eyepieces

Help in choosing a 5mm eyepiece

Posted By Ron Oehlert

I've over 400 pleasant purchases from E-Bay with some of them eyepieces, as anywhere (even Amart) use your Head when buying. And consider a Barlow negative-focal length lens to multiply the effective focal range of your existing eyepieces; use of a Barlow preserves comfortable eye-relief of longer focal length eyepieces, too.

May 21, 2010 07:51 PM Forum: Equipment Talk

What's it called?

Posted By Ron Oehlert

Perhaps more readily available (can be sourced locally at a Hardware store) is a threaded post with a sliding cross-rod (for tightening leverage), as commonly used for bicycle seat height adjustments without tools, etc. Performs the identical function as the TV Batwing screw (i.e. non-tool adjustment in zero-clearance situations).

June 2, 2010 02:08 PM Forum: ASTRONOMY

Lens cleaning

Posted By Ron Oehlert

Under the Equipment Talk forum catagory, notice How to Clean Your Corrector Plate posted by Greg Nowell.

June 2, 2010 02:36 PM Forum: Reflectors

2" focuser for Orion 3.6" OA

Posted By Ron Oehlert

As long as focuser height & range is satisfactory, you can simply exchange the focuser. However, it is doubtful the full Field Of View of a 2" diameter long focal length eyepiece can be realized; IOW likely there will be vignetting at the field edge due to diagonal size & placement. Use of a 1.25" 28mm or 32mm focal length eyepiece is probably the widest True Field Of View you can expect without vignetting. Or a 24mm SWA type 1.25" eyepiece will yield the same True FOV via a wider Apparent FOV & greater magnification.

June 23, 2010 07:08 PM Forum: Telescope Making

Tube rings for a 4" Dynascope

Posted By Ron Oehlert

Sure, your imagination is the limit. Like a DIY wood cradle (half rings) with an over-the-tube restraining strap for instance. A wingnut & eye-bolt on one end of the strap adjusts tension.

July 18, 2010 05:15 PM Forum: Eyepieces

eye relief for 18mm orthos?

Posted By Ron Oehlert

I've 25, 18, 12.5 & 9mm in the older volcano-top Circle-T ortho's. The eye lens is recessed down into the barrel so the 18mm just *fits* for a full FOV with my glasses hitting the metal, but it is not comfortable. And with glasses-On I cannot view the entire FOV when using the 12.5mm or 9mm. But, you do not need to wear glasses to view thru a scope (& shouldn't, in order to maximize observed detail) unless you also have Astigmatism. Or file the extraneous metal away to permit a more generous eye relief.