Televue
vs. Meade Focal
Reducer Comparison - TMB 80/480 First Light TEST -
Testing Setup: ST-10XME on Piggybacked TMB 80/480 Super APO (TMB_80-480_on_LX200.jpg), f/6 reduced further by TV.8XFR and Meade .63FR.
TV.8X is 60sec and Meade .63 is 20sec exposure taken within 1 hour of each other
in poor 2/5 seeing. Each image was focused using CCDSoftv5 @Focus routine immediately prior to each exposure. All are full size crops of image. Conclusion - There is always a trade off when you add glass to the imaging train. The Televue blows away Meade in resolution. It
appears to be well worth spending the extra money on quality focal reducers. The Meade reducer obviously softened up the image and bloated the FWHM of stars. NOTE: TMB 80/480 Specification/Test Results and Interferogram at bottom of page.
(Below) Center Crops- Televue FR wins in the center portion for
resolution against the Meade FR. Scroll Down for corner "Coma
Correction" comparison.
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All Full Frame Images Below Taken Using
a ST-10XME w/CFW10 on TMB 80/480
(Below) Televue 0.8x FR at 56mm (left) and at
53mm(right)
(Below) Meade 0.63x FR at
70mm on ST-10XME
TMB 80/480 Refractor Specification Sheet = .990 Strehl
Strehl Formula = 1 - ( 4(p2 x .0162) + 4(p4 x .0164) )
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