LRGB imaging in Light Polluted Area

[Robny]

Hi all

Just a quick question, with LRGB imaging with a MONO camera, would you still require an LP filter in front of each L, R, G and B.

On a side note, with "Galaxy Season" on the horizon are there still any NB targets available to go out, just trying to decide which filter set to purchase first

Thanks as always

Rob

[markarian]

I find I still need one even though the RGB filters take some of the LP out. L definitely needs it. I just keep my IDAS P1 in front of everything. Don't know if that's correct or not but it seems to work for me. Without it my images fog too quickly.

Mark

[Z3roCool]

I think the Veil is up later in the year and targets in Cygnus areas in general (Want to try a Widefield panel in NB). Wil llso be looking at Cocoon Nebula
Wizard Nebula and Elephant's Trunk.

Will be interested about the LP filter also with LRGB as I am going to shoot NB from my Bortle 6 area.

[mikey2000]

I live in an area of moderate LP (bortle 5 according to ClearOutside, I never ever saw the milky way from my chosen site...).  I gave up on L subs long ago and stick to RGB/Ha + my new Oiii only.     My ZWO RGB filters seem to do a decent job of filtering the local light pollution.  I then use 'synthetic luminance' in place of actual L.    I was always pleased with the results and finally decided to remove my Baader NeoDymium LP filter.  It feels like I have better results without the NeoDymium, especially Green. 

 

When I looked at the filter spectrum graphs for my particular filters and wavelengths, I decided to give it a try.  If narrowband is so faint and hard to catch, why throw away 10-30% with a LP filter? Can you look up graphs for your own set of filters?.

 

I now only use the L fitler for those awkward setting up moments, when platesolving needs a few extra stars

 

On the other question of Which Filter Next, I'd definitely recommend Ha (if you can manage long subs).  There's some marvellous Ha stuff out there.  In fact, if I had to choose just one filter to keep out of L, RGB Ha and Oiii, it would be Ha, every time.  I'm a little disappointed with my Oiii filter on the whole - it just seems there aren't so many targets that benefit from it.

[discardedastro]

Definitely +1 to the comments of only going Ha if you can do long exposures - most targets will take a reasonable amount of exposure, especially if you're using your smaller scope.

I'm in Bortle 2 skies and generally do fine with LRGB - but have considered a high transmissivity filter. We're mostly LED round here (starting to engage with the council on light pollution) which makes life a bit tricky.

[Robny]

Thanks....

I'm almost certain I'm going to plump for NB first.  Think I can only get 2filters initially so will be limited to bi-colour for a short perild of time, which is fine for me.

I'm think definitely Ha of course, but the sexond filter I was thinking Oiii?  Would thay be the sensible two first filters ro purchase?

[carastro]

Not much up at the moment in the way of narrowband.

Rosette Nebula if you can catch it before  it disappears.  Heart and Soul are possibles.

I live in Bortle 8 and tend to do HaRGB or narrowband.

Carole 

[Robny]

On 09/03/2019 at 11:30, carastro said:

Not much up at the moment in the way of narrowband.

Rosette Nebula if you can catch it before  it disappears.  Heart and Soul are possibles.

I live in Bortle 8 and tend to do HaRGB or narrowband.

Carole 

In that case it is probably going to be a race between the clouds and Rosette and I know which will win.

[GeorgeLiv]

Fascinating how no one ever questions what sort of light-pollution they have, rather than how much. Is it sodium, metal-halide type, is it induction or LED lighting? yourlightpollution.com

[Robny]

22 hours ago, GeorgeLiv said:

Fascinating how no one ever questions what sort of light-pollution they have, rather than how much. Is it sodium, metal-halide type, is it induction or LED lighting? yourlightpollution.com

My light pollution is LED, so I have a pretty good idea of what filter I need to combat it.  I wasn't sure if I needed to use one in front of LRGB filters.

[SamAndrew]

I thought my first LRGB came out quite well considering my sky is Bortle 8. This was without any additional light pollution filters, just the standard ZWO LRGB filters.

 

[Robny]

10 minutes ago, SamAndrew said:

I thought my first LRGB came out quite well considering my sky is Bortle 8. This was without any additional light pollution filters, just the standard ZWO LRGB filters.

 

Thanks for sharing this and good to see a physical example of what can be done...it looks awesome.