Skywatcher Evostar vs Black Diamond

[Alcyoneus (Prashaant)]

Hi all, i was just looking through Skywatcher's catalogue (specifically at their refractor options) and I noticed that the Black diamond series had very similar specs to the Evostar series although the price was much higher for the Evostar.

I just wanted to know if there were any major differences because i cant seem to find any.

Cheers.

[raymo]

Hi Prashaant,
The black diamond range of refractors are basic achromats which will show
colours around the edge of bright objects, due to all colours not coming to focus at the same point because of their differing wavelengths.

Evostar models have better colour correction and will show minimal false
colour. Although they too are doublets, they are usually known as
apochromats like the triplet lens models.
raymo

[Alcyoneus (Prashaant)]

Oh okay, thanks for the help mate.

[Wilsil (Wilco)]

Originally Posted by raymo

Hi Prashaant,
The black diamond range of refractors are basic achromats which will show
colours around the edge of bright objects, due to all colours not coming to focus at the same point because of their differing wavelengths.

Evostar models have better colour correction and will show minimal false
colour. Although they too are doublets, they are usually known as
apochromats like the triplet lens models.
raymo

I guess this shouldn't matter if you are imaging with a mono camera as you are using separate filters for each color?

[AdamJL]

Originally Posted by Wilsil

I guess this shouldn't matter if you are imaging with a mono camera as you are using separate filters for each color?

if you're using a luminance filter, it will impact because all channels will be combined. You'd need a synthetic luminance layer from your combined RGB data to combat that instead of using a normal luminance filter.