Right so a semi-apo it is then. I'm just catching up with threads/posts on this scope. I'm interested for sure as part corrected wide field sounds like a nice step up from Skywatcher's ST80/120.
Hi i had the same questions and i send an email to BRESSER. Here is their answer. Hope it helps!
"Here is the mail with the reply from BRESSER:
Dear Mr. ...,
thank you for your interest in a BRESSER telescope.
About your questions:
- What type of ED glass do you use?
What exact ED glass it is is a business secret, I ask for your understanding. But of course, at this price range it is logical that it is a very cheap ED glass.
- How severe chromatic aberration i must expect?
It is like a normal achromatic refractor around F/7.
- Concerning ED glass, can you classified it as a semi apo telescope?
No! We classify it clearly only as achromatic refractor! We use ED glass at this telescope only because at F/4.5 you cannot really use normal glass.
- Is it suitable for astrophotography and EAA?
This telescope is made for wide-field observing. For example the North-America nebulae is a very nice object to observe at this telescope. It is also a very nice telescope for travelling.
Of course, you can also use it for imaging, but you will get some color at bright stars.
But this telescope is NOT a apo-chromatic flat-field astrograph!