Do I need to use a diagonal with a Mak?

[Macavity]

MAKs & CATs are pleasingly accommodating re. adding or subtracting
random bits & pieces to / from the optical path! I happily add a good 3"
of external focuser to my MAK150 (retaining the diagonal) visually.

Quite what this does to the "carefully optimised"(?) optical design of
the system one might like to ponder! A few years back mere mention
of Maksutovs elicited cries of "Planetary Only" from theoreticians...
Until those who had *tried* 2" diagonals / eyepieces were believed! 

These scopes can be surprisingly versatile visually! If you are imaging,
try barlowing / reducing upto FOUR times? (Can work "well enough") 
I can see no obvious advantage of diagonal-less visual observation??? 
But the key is suck it and see Experimentation?

[Alan64]

1 hour ago, Peter Drew said:

I've never seen scatter as bad in any telescope as shown in the second photo unless the optics were dewed up.  

We were having a rather dry spell that mid-to-late summer, which extended into early fall.  It was July 26th, 2015, around 09:00 PM CST here in the States, when those images were taken.  It was so dry in fact that I was finally able to bring out the 102mm f/8 refractor, and after two years in storage.  I don't bring the refractor out when dew is a possibility.

In addition, the 150mm f/5 through which both images were taken, was unflocked, stock, at that time.  I may have suggested earlier that it had been flocked at that time, but no.  It was then that I decided to flock and blacken the interior, and during the following January of 2016.

[Peter Drew]

5 minutes ago, Alan64 said:

We were having a rather dry spell that mid-to-late summer, which extended into early fall.  It was July 26th, 2015, around 09:00 PM CST here in the States, when those images were taken.  It was so dry in fact that I was finally able to bring out the 102mm f/8 refractor, and after two years in storage.  I don't bring the refractor out when dew is a possibility.

With respect, I wasn't trying to infer that the optics shown in the photo were dewed up, just my previous experience.