NavList:
A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
Re: Jupiter Lunar DSLR Camera Trial
From: Marcel Tschudin
Date: 2010 Sep 23, 12:44 +0300
From: Marcel Tschudin
Date: 2010 Sep 23, 12:44 +0300
The results Greg obtained Day Venus DSLR Trial: 0.4' and 0.2' DSLR Venus Lunar: 1.4' and here now Jupiter Lunar DSLR Camera Trial: 1.5' and 0.5' agree well with the expected +/- 0.84' accuracy resulting from more than 100 calibration observations. This accuracy depends not only on the camera-lens system, but also on the techniques used for obtaining the angular distance from the photo. For the latter Greg preferred to introduce some simplifications in order to make it more practical for him. Without these simplifications the observations are expected to scatter somewhat less. Greg's last observation shows also something else. All the calibration photos were taken with an aperture of F22. This observation was however done with an aperture of F4. The results of this observation indicate that the calibration is also valid for this larger aperture. I guess this is a sign for the quality of the lens which Greg is using. Marcel On Thu, Sep 23, 2010 at 7:17 AM, Greg Rudzinskiwrote: > This evening the eastern sky was clear for a near/far Jupiter Luner DSLR > camera trial and a near/far Jupiter Lunar using a 4x40 scoped Plath as a > check. > > 10MP DSLR 50mm lens 1/200 sec. ISO 1600 F4 infinite focus > 9/23/2010 UT 3:20:40 Lat.34� 10.4'N Lon.119� 13.8'W > Near Limb 5�31.4' clearing 45.3' longitude (-1.5') > Far Limb 6� 3.4' clearing 15.7' longitude ( 0.5') > cleared by Reed online program > > Plath 4x40 scope > 9/23/2010 UT 2:53:16 Lat.34� 10.4'N Lon.119� 13.8'W > Near Limb 5� 32.4' clearing 2.2' longitude (-0.1') > 9/23/2010 UT 3:35:6 > Far Limb 6� 3.0' clearing 7.6' longitude (-0.3') > cleared by Reed online program > > The sextant is still the champion instrument when it comes to taking Lunars > but the DSLR camera with a 50mm lens put in a respectable showing. > > Greg Rudzinski > ---------------------------------------------------------------- > NavList message boards and member settings: www.fer3.com/NavList > Members may optionally receive posts by email. > To cancel email delivery, send a message to NoMail[at]fer3.com > ----------------------------------------------------------------