Greg - Celestron SkyScout 90mm refractor & planetarium
Quote:Please tell us that you are just kidding...?
Quote:What happened to the # in the calculated Field Stop column in the third version or am I missing them on my iPad copy ??
Quote:Also how we're the various Field Stops calc.? By actual physical measurement with a tape, inside callipers etc. ?
Quote:If not physically measured the calc. Field Stop could be significantly different ( probably much less ) based on the actual design of, shall we call it the Field Stop Ring, in the barrel of each individual manufacturers EP !?
Quote:I don't understand what distortion has to do with the amount of apparent field that will fit within the field stop for a given widefield and/or 2" EP ? As well, other than in an odd case, why don't the EP manufacturers clearly identify the Field Stop spec.for their product, why make the buyer do the leg work as I think it is a fairly important # to have when buying an EP or am I wrong in my thoughts ? This is a learning experience for me as I gain knowledge in this hobby !
Quote:I am having a hard time accessing the columns to enter my data as I get no response from my iPad when I hit the data line !? What's the secret as I have tried it several times ! Also I am going to physically measure the Field Stop as a comparison on my 2" and 1.25" EP's
Quote:The top line is exactly correct ! Like with everything else it's just nice to have a number for reference / comparison and to take it for what it is worth !
Quote:Your 01/09/06 article Eyepiece Qualities & Aberrations explains a lot !
Sometimes (amateur) astronomy -or should I say optics- can become a leeeeettllle bit overwhelming.
Kudos to Don who -as it turns out- is either single, or has a very accommodating (another optometrical term) wife...
Well done and great work Don,
Like I mentioned in my article.. you are truly the telescope guru!!!
Your work is most helpful and much appreciated!!
CPC1100 AstroTelescopes 80 mm f/7, 102mm f/11 ES AR127mm f/6.5 Zummell 254mm F4.9 Dob Coronado SolarMax II 60mm Delos 14mm, Axiom LX 10mm, 15mm 1.25"; 19mm, 23mm, 31mm 2" AstroTech Hi Grd Plossl 4mm, 6mm, 12.5mm, 17mm, 20mm UO Abbe Ortho Volcano tops smoothies Titan 26mm 2" ES 20mm 1.25" Celestron 40mm Plossl (came w/ scope) 1.25" Meade 5000 series 14mm Plossl 1.25" Baader Hyperion MkIII 8-24mm Zoom Pentax XW 7mm 1.25" TMB II planetary 3.2mm, 5mm 1.25" Lumicon UHC filter 2", OIII 2"
Don, I am a professional web developer. Would you object to me taking the spreadsheet and making it into a searchable database on the web? Is there any problem (mainly copyright) with reproducing manufacturer specs?
The data on that list is from published sources, and not copyrighted.
But I am in the process of doing the 2014 version and have a substantially updated version.
Please contact me at email@example.com and I will send you the latest version whenever you are ready for the data. I like the idea.