Skywatcher 0.9x coma corrector vs 1x

[rnobleeddy]

Apologies for another cc question. I have searched high and low and can't find an answer.

FLO sell the 0.9x sky watcher coma corrector which gets mixed reviews, but seems like a fair choice for the price.

However, what I assumed was the same product at https://www.rothervalleyoptics.co.uk/skywatcher-2-coma-corrector.html is specifically listed as not impacting the magnification so is presumably a 1x. Just wondering if anyone has tried this one? 

As best I can tell there must be 2 versions, with the 1x getting pretty poor reviews at https://www.astroshop.eu/flatteners-correctors-reducers/skywatcher-2-coma-corrector-for-newtonian-telescopes/p,18852#tab_bar_2_select, but I've seen complaints about reflections in threads about the 0.9x too.

I got a second hand scope with the tube already cut off so that's no an issue I need to worry about with the 0.9x.

 

[toxic]

you should be ok with the 0.9 version if your scope is F5 or slower but F4 and you will struggle to get a flat field i have a SW 200pds with the 0.9 cc and it was fine but it is no good on my SW 250 Quattro i had to get the SW aplanatic cc hope this helps.

 

[rnobleeddy]

 

1 hour ago, toxic said:

you should be ok with the 0.9 version if your scope is F5 or slower but F4 and you will struggle to get a flat field i have a SW 200pds with the 0.9 cc and it was fine but it is no good on my SW 250 Quattro i had to get the SW aplanatic cc hope this helps.

 

Sorry, it was too late when I posted last night. I have a 130PDS so F5.

Given the numerous threads on cc's on here I find it surprising that there's little commentary about the the two models.  I'm not sure it's particularly logical that one version from SW would be OK and the other rubbish, but stranger things have happened!

The real motivation of the question was that someone is selling the 1x Rother Valley version on astrobuysell so was trying to work out if I should get that or  order the 0.9x.

 

 

[alacant]

19 hours ago, rnobleeddy said:

with the 1x getting pretty poor reviews

Hi.

AFAICT, the two coma correctors to which you link are the same. Product description is perhaps not astroshop.eu's strong point.

SW do however market  a 1x coma corrector. It's called Aplanatic and is a copy of the GPU coma corrector but without possibility of adjustment. 

The latter is by far the superior of the two at any focal ratio, as is reflected (sorry) in the price. But it's heavy and maybe best avoided for PDS focusers.

HTH

Edited June 10, 2020 by alacant