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Andromeda in a bortle 6, should I use a light pollution filter ?

Acquisition Deep Sky M31 Galaxy
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Eric Gagne avatar
Eric Gagne avatar
Hello forum,

I am planning on shooting Andromeda next week.  It will be my first attempt at a galaxy.  I recently bought a Optolong L-Pro but haven't had a chance to try it yet so I really have no idea how it will affect my subs.

I am wondering….. Should I use it for Andromeda under bortle 6 or would I be better off with no filter at all ?

I could also use advice on acquisition technique, particularly exposure time.  So far I have only done emission nebulae.  I have been doing 5 minutes exposure since I started guiding.

Would that work for galaxies as well or is there a different set of "rules" ?
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Alan Brunelle avatar
Alan Brunelle avatar
Are you doing OSC?

At Bortle 6 you will be operating with a considerable amount of city/suburban light pollution.  So you should see considerable benefit.  The down side is that galaxy light is broad band, so you will lose some photons.  But the l-pro is pretty generous, so it should work well and it will calibrate to true color (for OSC images).

I am in low Bortle 4 skies.  My camera has no integral UV/IR cut window, so the L-pro lives in my filter drawer full time.  It does double duty very well.  Even used it in Bortle 1 in New Mexico.  My OSC always calibrates with hardly a color shift.   If you don't use the L-pro, were you going to use a UV/IR Cut?
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wsg avatar
wsg avatar
Eric.

This is a link to every image of M31 in the history of Astrobin that has won a TPN, TP or IOTD.


https://www.astrobin.com/search/?q=M31&d=i&subject=&telescope=&camera=&date_published_min=2011-11-09&date_published_max=2023-12-01&award=iotd%2Ctop-pick%2Ctop-pick-nomination&sort=


You- can search the acquisition details of the nearly 600 images to see every available detail of how they were captured.
You- can find equipment similar to your own, along with what filters, if any, were used and also the integration time and exposure it takes to capture M31.
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