Posts Made By: Greg Bradley

Fantastic!

Greg.

What a wonderful image.Very vibrant and interesting.

Greg.

Fantastic Thomas.

Did you image Corona Australis this season from Victoria?
Also there are a few big dust clouds near Rho Ophiuchi.


Greg.

FSQ106EDX. Its native F5. You can get a reducer for it that takes it to F3.64,

http://www.pbase.com/gregbradley/image/93945265 (not a mosaic, STL11 FSQ106EDX with reducer).

Awesome machine, incredibly well built. No other refractor I know of goes to F3.64.

NP101 seems a great scope.Similar design to the FSQ.

Which was first on the market the NP101 or the FSQ?

Greg.

I'd verify this.

My experience is an STL sized camera needs a 4 inch focuser or you are going to have a hell of a time with vignetting. 2.7 inch focusers are simply too small for the large chip cameras.

Also a reducer will not give you a flat field unless you have the specialised AstroPhysics reducers. So F6 on a TSA is misleading as it will not be a flat field and you will get coma on anything larger than a DSLR and perhaps even a DSLR. Hence it is useless unless using a "small" chipped camera.

So if you intend imaging with a DSLR or smaller chipped camera then this is a viable choice (I would still examine F6 TSA images very carefully for coma even with DSLRs).

I have had an FS152 and it could not handle the STL chip without the 4 inch focuser and flattener. No/doublet/triplet APO can. So its a choice of scopes with 3.5 inches of focuser or more with a dedicated flattener.Add in F5 as a requirement and you've now got only 2 or 3 scopes!!

Hence the popularity of the FSQ or NP101 Petsval design which gives falt field without vignetting 50mm or greater (FSQ is 60mm or more I believe).

As CCD chips become larger the stress on the optics and especially flat fields is becoming harder. Very few scopes really can handle it. Your choices are more limited than you realise: AP, TEC, some Tak, some TMB. Basically anyone who offers a 4 inch focuser and a matching flattener. Now you wanted fast scopes. That limits it even further.

AP traveller with flattener?, Tak FSQ F5, NP101 F5 eehh rrr uhmm I am running out of scopes here!

If you stay with an imaging chip no bigger than a DSLR your choices are much wider.

Given what you've asked I'd say your choice is either Tak FSQ or TV NP101. Perhaps another is the Pentax range.
FSQ would be the better choice with its reducer cost not considered.

Reducers on APOs are essentially useless these days unless you have the AP TCC or are content to never go above DSLR sized cameras.

Greg.

Very nice.

Greg.

Fabulous LMC.

I don't think adding Ha will do much as you have already captured the Ha very well with the LRGB and gotten a very nice colour balance.

Greg.

That's an excellent Helix Jim.

Greg.

A stunner.

So are 206EDF's planned for production runs then?

Greg.

That is fantastic.

Greg.