Half decent backyard vs dark site for imaging, what does 0.3mag bring?

[GTom]

Going for a trip in Eastern Europe soon, as the poor folks there don't have much clouds I am definitely bringing the astro gear with. The accommodation is already in a useable Bortle 4 zone, according to the Atlas 21.4mag skies. However, driving away about 30 minutes I can get to Bortle3 with 21.7mag.

I was wondering, with all the modern tech, how does the 0.3mag difference translate to e.g. L-frame wide band results?

 

Their celestial darkness will be a short 4.5 hours, I won't be limited by battery capacities or lack of warm tea in a nomadic setting although unsure if I can find a similarly wind protected site if wind becomes an issue.

Edited July 7 by GTom

[Elp]

It'll make a difference but I don't think it'll be that significant, the main factor might be whether there's a LP source causing a sky glow in the direction you're imaging.

[TiffsAndAstro]

2 bortles is a factor of 8 compared  my bortle6 back yard. So if it were me I'd need to know if that extra 0.3 increased the factor of 8 enough to outweigh the 60 minute drive, lack of room service scary sounding eastern European wildlife lack of mains power and travelling family / companions

I think I'd settle for  just 8 times faster photon gathering

Enjoy your trip!

[GTom]

Re wildlife, for another 0.5(!) mag I could do 5 hours driving and share the night with some Carpathian brown bears🤔😅

That's also another 1500m elevation asl too though.

Edited July 7 by GTom

[TiffsAndAstro]

1 minute ago, GTom said:

Re wildlife, for another 0.5(!) mag I could do 5 hours driving and share the night with some Carpathian brown bears🤔😅

Many years ago I read some weird but decent vampire ish books part set in the Carpathians. Always wanted to visit, but now also for dark skies. No chance now  if I need to consider bears helping me polar align.

[GTom]

Been there 30 odd years ago camping, about this region. Saw only a single big fella from faar away. They say though their population multiplied since!

Fantastic skies if clear but certainly more clouds than on the plains.

 

 

Edited July 7 by GTom

[TiffsAndAstro]

2 minutes ago, GTom said:

Been there 30 odd years ago camping, about this region. Saw only a single big fella from faar away. They say though their population multiplied since!

 

 

Yeah vampires are scary. Did you see any bears though?

[GTom]

No, daylight is for werewolves only

[Pompey Monkey]

7 hours ago, GTom said:

Re wildlife, for another 0.5(!) mag I could do 5 hours driving and share the night with some Carpathian brown bears🤔😅

That's also another 1500m elevation asl too though.

1500m elevation trumps bottle.

No doubt. The higher you go, the fewer particulates there are to backscatter any lp

[Pompey Monkey]

Just now, Pompey Monkey said:

1500m elevation trumps bortle.

No doubt. The higher you go, the fewer particulates there are to backscatter any lp

 

[Pompey Monkey]

Double post.

Phones, eh.

[vlaiv]

0.3 mag is significant for visual, but is almost insignificant for imaging.

Just to put it into perspective - transparency can vary more than that between two nights.

I once calculated the difference between 18.5 and 20.5 (so two mags of difference) - and result was about x6 imaging time needed to compensate.

Quick calculation shows that with fast scope (f/4) working at ~1.3"/px - you get difference of around 30% in imaging time. Or rather you need to image for 30% more at 21.4 versus 21.7 if all other things are equal to hit the same SNR.

However - one will have SNR of 4.89 and other will have 5.53 (based on parameters I used) and I don't think you'll easily tell the difference in level of noise in two images.