Great Expectations

[marcdearn]

Hello again everyone,

Just trying to make a obs list for SGL5 and wondered what a reasonable expectation would be for magnitude through a 130mm Newt?

Don't want to waste time looking for DSO's I have no chance of seeing...

Thanks in advance!

[Bizibilder]

Google "magnitude limit" for loads of sites that will calculate a theoretical value - for your 130mm it is around mag 13. BUT this is theoretical and will depend very much more on the atmosphere and light pollution of the site you are observing from.

[marcdearn]

Thanks for that! Should be able to see most of the things on the list i am looking at then

Most are Mag 10 or brighter

[Bizibilder]

Don't forget that the magnitude of a "fuzzy" is NOT the same as that of a star. I'm not sure if there is a "measure" available but you can safely bet that mag 7 or 8 in the catalogues is probably nearer the mark. The brighter clusters are a different matter as they contain stars of measurable magnitude.