Posts Made By: Magnus Ahrling

Any opinion regarding Coulter Optics (Murnaghan?) 8"f/4 mirror?
It`s bought -95-97 I think.
Want to replace my Cave mirror f/4,5 (-73) which is awfull above 100X. (No Alika Herring signature on it;-)
I have also decided to replace the original Cave 2,14" secondary with a Newport Glass secondary (1/10 wave)
/Magnus

Hi
Iam seriusely considering purchasing a C6.
Anyone in this forum who owns this C6?
If so what do you think of it........
Thanks,
Magnus

I am about to order a Sky-Watcher 6" f/8. Anyone who has used this scope , what`s the good and bad sides of it?
I will just order the OTA and use it on my EQ mount.
Clear Skies,
Magnus

Hi!
Has anyone observed with Bresser/Messier Newtonians?
I am esp. intressted in 6" f/8.
Are they the same as Synta Instruments?
Happy for info
Clear Skies,
Magnus

My C80ED does not show a complete diffraction ring around brighter stars than, say, mag 2-3.
Instead I see an half arc of diffraction ring at 160X. On the other side of the star there is no diffraction ring at all.
Out of focus I see very nice concentric an even rings, almost identical on both sides indicating no flaws at all. Maybe a bit washed out outside focus compared to inside.
I split 1.5" binaries and split delta Cyg on good nights, observed Io and Europa transits as well as GRS last spring altough Jupiter was low in the sky, observe craterlets in Plato, Cassdiv and Crepè ring as well as subtle bandings on Saturn, lot of markings on Mars last apperation as well as SPC. So there is not much wrong with the scope. But the "half diffraction ring" around brighter stars is ugly and irritates me.
So what is it....misscollimation? Too bad in that case as C80ED can`t be collimated as far as I know
Has anyone else the same experience?

Clear Skies,
Magnus

PS I use WO 2" diagonal Intes 2,2X Barlow and 9mm Antares eyp.
The same equipment with my 120ST shows a very nice diffraction ring at focus on brighter stars at 160X

Can a 6" f/8 Newtonian be as good as a 4" ED/APO when it comes to planetary, binaries and globular clusters?
Has anyone tried this Sky-Watcher (Synta) 6" f/8 OTA? I`d like to buy this OTA and mount it on my EQ3 or possible my Vixen Porta....
/Magnus

Hi!

Guess this thread must have been up a million times....
Still here I go: Which scope do you think would performe best for planets, binaries and globular clusters, a Synta 4" ED or a 6" f/8 Newton ?
The cost for the OTA:s are just about the same.
I already have EQ mount.

The scopes I have are S-W 4,7" f/5 refractor and a C80ED.

Hope anyone can help me with advice....

/Magnus

My Orion Optics UK 8" f/6 Newton arrived this evening. (need I say the sky is cloudy!?).
Anyway I got a Zygotest with it at wavelength 632,8nm. The figures goes like this:Strehl:0,982, PV Wavefront:0,139 Wave, rms:0,021 Wave,
AstMag: 0,029 Wave.
Comments, please. I will be able to tell when I can test myself, but it would be nice to know what all this figures means. The only figure Iam familiar with is Strehl and it seems quite good.
I bought the scope at 1/6 Lambda.
Thanks for help.

Magnus

Why is the sky dark at night? There are so many stars and galaxies shining, so they should shine as bright as our Sun does in daytime.
I have read all`bout (well almost!) Olbers Paradox but can`t find the answer.
Can anybody here enlighten me!

Magnus

Anybody who knows what`s the difference between SynScan and SkyScan Sky-Watcher Go-To hand controll?
//Magnus