ED vs APO - in layman's terms

[ollypenrice]

The very high end refractors have always been there. The outstandingly good budget ones, now plentiful, have not. This is the age of the affordable telescope so let's not get hung up on how expensive the high end stuff is. The real story is about how good the cheap stuff now is.

And if you're short of cash, why go for a refractor in the first place? There are insanely good budget Newts available these days and blessèd be John Dobson for showing us how to mount them.

The Apos and semi-apos debate is a bit of a red herring since 1) the difference is very slight, 2) the individual scope rather than it's generic type is more influential of its performance and, 3) the issue is not the same in visual observing as in imaging.  (In imaging you are far more likely to be undone by the focuser than by the level of apochromatism. Other key things in imaging, more important than colour correction, are flat field size and thermal stability of focus.) And then there's personal taste. Some people are upset by the Tak FSQ's 'inverse lighthouse beams' on bright stars and some are not. I'm a 'not.'

Olly

[Tiny Clanger]

4 minutes ago, ollypenrice said:

The very high end refractors have always been there. The outstandingly good budget ones, now plentiful, have not. This is the age of the affordable telescope so let's not get hung up on how expensive the high end stuff is. The real story is about how good the cheap stuff now is.

And if you're short of cash, why go for a refractor in the first place? There are insanely good budget Newts available these days and blessèd be John Dobson for showing us how to mount them.

Amen.

[Adam J]

2 hours ago, John said:

Just because you are not comfortable with it, does not make it a "nothing statement". By all means use the magnification that works well for you and your eyes but don't knock others who find that they enjoy something else when the conditions allow.

I think people report what has worked for them honestly and with enthusiasm on here and it would be a shame to dampen that.

 

 

I used the terms: "for me", "I would be comfortable with" and "so to me". 

Not sure how you read that as me talking about anything other than my own experiences. 

For me it would make little difference to own a 4 inch scope capable of 400x over one capable of 250x unless I want to see nothing but floaters. So to me the distinction in quality is meaningless.

I never said anything about anyone else but it's something everyone should consider against their expectations of performance for a low aperture premium refractor. Just because it is capable of 400x doesn't mean your eyes are. 

I am knocking no one, infact if you have the eyes for it i am quite envious. 

Edited February 28, 2021 by Adam J

[John]

6 minutes ago, Adam J said:

I used the terms: "for me", "I would be comfortable with" and "so to me". 

Not sure how you read that as me talking about anything other than my own experiences. 

For me it would make little difference to own a 4 inch scope capable of 400x over one capable of 250x unless I want to see nothing but floaters. So to me the distinction in quality is meaningless.

I never said anything about anyone else but it's something everyone should consider against their expectations of performance for a low aperture premium refractor. Just because it is capable of 400x doesn't mean your eyes are. 

I am knocking no one, infact if you have the eyes for it i am quite envious. 

This seems to refer to "anyone else":

"....to me it is a complete nothing statement when people make claims like that...."

By all means think what you like about what others posts but perhaps best to keep it to yourself ?

 

 

[Adam J]

12 minutes ago, John said:

This seems to refer to "anyone else":

"....to me it is a complete nothing statement when people make claims like that...."

By all means think what you like about what others posts but perhaps best to keep it to yourself ?

 

 

As in it's nothing to me as it's something I can't experience. Doubtless it's meaningful to those who can. You are miss reading my tone. 

So having clarified that, I'll be going now. 

Edited February 28, 2021 by Adam J

[Carl Au]

4 hours ago, John said:

Just because you are not comfortable with it, does not make it a "nothing statement". By all means use the magnification that works well for you and your eyes but don't knock others who find that they enjoy something else when the conditions allow.

I think people report what has worked for them honestly and with enthusiasm on here and it would be a shame to dampen that.

 

 

Exactly, lets just love the hobby, we do it for fun after all.