Will fitting a baffle make before/after data incompatible?

[BrendanC]

Hi all,

I just got a baffle to fit to the primary on my 130PDS, in an attempt to get my stars a bit more defined. It goes around the outside of the primary and hides the primary mirror clips - very much like this: https://www.teleskop-express.de/shop/product_info.php/language/en/info/p12358_Wega-Primary-Mirror-Baffle-for-Skywatcher-Newtonian-130PDS.html

I've yet to fit it, but I just had a thought: if I do fit it, will it affect my focal length? And if so, will that mean data acquired after fitting the baffle, will be incompatible with data acquired before it? As in, will images acquired with the baffle fitted, register and stack ok in DSS with images acquired without the baffle fitted? I'd rather know either way before I fit it!

Thanks, Brendan

Edited July 4, 2021 by BrendanC

[Gfamily]

I can't see that it would affect your focal length, but it will increase your focal ratio (in that it will reduce your aperture by about 1cm - I reckon about 0.5cm at each edge) 

Edited July 4, 2021 by Gfamily

[BrendanC]

Thanks!  

So, data before and after should still work together then?

[BrendanC]

Actually, I decided just to think about this for a moment, and I completely get it now. Of course it won't change the focal length but it will just make the scope a bit slower.

I think I get it now.

Thanks.