I've been curious if the new Celestron StarSense 130mm F/5 reflector has a parabolic mirror or a spherical mirror.
The Celestron Astromaster 130mm F/5 has a spherical mirror. This is stated in Celestron's own knowledge base: https://www.celestro...-the-difference
The Celestron Nexstar 130SLT (also a 130mm F/5 reflector) is reported to have a parabolic mirror, and a few retailers list it as such. The higher cost does seem to indicate a parabola would be likely.
But given the StarSense line has the same 114mm Bird Jones as the AstroMaster line, I'm hesitant to say that the StarSense 130DX is actually the same OTA as the Nexstar 130 SLT, rather than the AstroMaster 130.
As such, I contacted Celestron, and they first told me that *all of their reflectors* use parabolic mirrors.
Finding that strange, given their own knowledge base explicitly states the AstroMaster 130 has a spherical mirror, and the fact that they offer two Bird Jones scopes (PowerSeeker 127EQ and AstroMaster 114EQ), I asked them to clarify.
They said that all of their "true" Newtonians have parabolic mirrors, as spherical mirrors would degrade performance too much otherwise. They just ignored the fact that their knowledge base says otherwise for the AstroMaster, and I'm fairly certain the PowerSeeker 114EQ is spherical, as is the AstroMaster 76 (though at that focal ratio it's just as good as a parabola).
So what actually *is* the verdict on all of Celestron's reflectors?:
- Nexstar 130SLT (parabolic, retailer advertised)
- AstroFi 130 (parabolic, unconfirmed - appears to be a rebrand/electronics upgrade of the 130SLT)
- SkyProdigy 130 (parabolic, unconfirmed - also appears to be the 130SLT with a different mount/chasis)
- StarSense Explorer 130DX (parabolic? spherical?)
- StarSense Explorer 114 (spherical, Bird-Jones - undisputed by Celestron)
- PowerSeeker 114EQ (parabolic, retailer advertised, though I thought all of these 114/910 mirrors were spherical these days. Probably irrelevant given the focal ratio.)
- PowerSeeker 127EQ (spherical, Bird-Jones - undisputed by Celestron)
- AstroMaster 130 (spherical, both confirmed in knowledge base AND disputed by Celestron support...)
- AstroMaster 114 (spherical, Bird-Jones - undisputed by Celestron)
- AstroMaster 76 (parabolic, retailer advertised)
- FirstScope 76 (spherical, unconfirmed but most likely given the other variations of this scope. Disputed by Celestron support...)
- FirstScope 76 Signature Series (spherical, confirmed in specs - disputed by Celestron support...)
- FirstScope 76 National Park Foundation Edition (spherical, confirmed in specs - disputed by Celestron support...)
- Cometron 76 (spherical, confirmed in specs - disputed by Celestron support...)
- Cometron 114 (parabolic, confirmed in specs - undisputed by Celestron support)
- ExploraScope 114 (spherical, Bird-Jones - undisputed by Celestron)
- LCM 114 (spherical, Bird-Jones - undisputed by Celestron)
- Advanced VX 8" (parabolic, confirmed in specs - undisputed by Celestron support)
- Advanced VX 6" (parabolic, confirmed in specs - undisputed by Celestron support)
- Omni XLT 150 (parabolic??, potentially confirmed in retailer advertising using weird language) - this is an odd duck. They won't explicitly say "parabolic". Instead, they say "aspheric shaping technology" and "virtually no spherical aberration". So is this like... a semi-parabola???
Anyone able to shed more light on this?
Also, the three scopes with parabolic listings are all advertised as such by only B&H Photo. No other retailer lists them as parabolic, which makes me wonder if B&H may just be adding "parabolic" to make the scopes more appealing.
The reason I question it is because the AstroMaster 76 with an F/9.2 focal ratio *doesn't need to be parabolic*, and yet the FirstScope/Cometron 76 lines with ultra short focal ratios are spherical. Something is amiss here. It's odd that the short focal ratio scopes would be spherical, but then Celestron decides that the long focal ratio AstroMaster 76 needs to be parabolic. This makes me take B&H's listings with a grain of salt.
Edited by CrazyPanda, 22 October 2020 - 12:14 AM.