Quote:As Jim stated, as long as you use a quality barlow lens, you should not notice any major negative effect.
Quote:They barlow quite well. Uae good barlow, of course.Short eye relief doesn't bother me a bit, so I go for the "least glass" option....
Quote:They perform much better in slow telescopes. At f/14.4 to f/16.7 they rock. At f/8.6 to f/10, they are still excellent. At f/7 they start to weaken even on axis. Faster than that, there are better choices.Regards,Jim
Quote:Here's my "Ortho" collection, by the way:My faves are the Pentax SMCs.- Jim
C10NGT, Z8, 150 Rumak, XLT 150, C6, C5, SW5 Newt, 4.5 Ball, C102GT, C90, ST80, A70LF; 15x70, 25x100; Burgess BV; Paracorr II; T6 2.5, XO 2.58/5.1, Ethos-SX 3.7, Delos 4.5, TV Plossl 7.4-26, BCO 10, Hutech HC 12.5, Sterling 12.5-25, ES100 14, CZJ H 16/25, CZJ O 16, M5k UWA 24, T5 31, Ultrascopic 35, Titan-II 40; Bino Pairs M5k UWA 6.7, Baader Zoom 8-24, M5k SWA 24, TV Plossl 26, RKE 28.7; Zooms NZ 2-4, NZ 3-6, Leica ASPH 8.9-17.8, Baader 8-24; Baader Zoom Barlow, VIP Barlow
C14 XLT, CGE NexSTAR 11 GPS + 120ST APM/TMB 130/780, AT111EDT SW EQ5P (2" Tripod/20" Pier) XW's 3.5mm - 20mm, 28mm RG, TVZ 2-4 ES14mm/20mm 100° UWAN 28mm,Paragon 40mm, TV55, Meade 2X 2" TeleXtender TMB SMC 4mm-16mm, Pentax 0-18, CZJ 0-25 EarthWin PFS-DBSE, WO DuraBright, AP MaxBright TV Bino's Bino Sets X 2: UO H.D's ~ 5mm-18mm, TV Pl.(NJ's)7.4mm - 40mm 16T5's, 24mm Pans Canon 18X50 IS Pentax 7X35 (9.3°
Quote:While not generally accepted yet, your results certainly mirror my own field testing.
Quote:Ask any refractor-owner who invested a small fortune in their latest top quality glass and they will happily tell tales about how their ridiculously expensive 4" refractors "out-performs" cheap 12" dobs right and left. Heck, let's make it 18" if the seeing isn't perfect, we all know how poorly those light-buckets perform when the seeing isn't perfect, right?
Quote:Mike, I replaced my UO VT's with UO H.D.'s as I found them a tad better.
Quote:I've also compared the Brandon's to the UO H.D.'s and found them to be more similar than different. However, others feel the Brandon's are superior for Star color saturation (which I'm not into).
Quote:In direct comparison (UO H.D.'s) on Planets and DSO's I found the Pentax Or. go deeper and offer a darker background. I only sold mine as I had the TMB SMC's as well. The difference wasn't huge, but noticeable.