LP Filters?

[Jm1973]

Hi All.

 

I am shooting from a fairly light-polluted area probably Bortle Class 5 or 6. I always have to spend time removing the LP from my stacked images.

I am considering buying a LP filter, but am unsure whether to buy a clip-in for my camera (a D3300), or something to attach to the T-ring, or any other option available.

I also am not sure what filter I need, and what is a reputable brand or type of filter, how much do I need to spend etc.

Also I understand a LP filter is subtractive, so I will be losing some light - is it even worth it?

Any thoughts, or recommendatioons are very welcome.

 

[alan potts]

Really need to know what type of lighting you are having problems with as they require different filters. I have a small LED light issue from the town 4 miles away, for this I need the IDAS  LPS D2, I am considering buying one in the next couple of days. Orange street light require a different filter I believe.

Alan

[Jm1973]

I was thinking of more of a general purpose filter if possible. I live in the outskirts of Bristol. There are white streetlights, several neighbors have security and garden lights that come on randomly, and there is the general skyglow that comes from living a few miles from the centre of a city. I couldn't really say what type of LP I am specifically suffering with.

Edited October 29, 2020 by Jm1973

[Seelive]

Unfortunately, unlike the old orange low  pressure sodium lights that only omit in a very narrow bandwidth which are easily removed by filters such as the IDAS D2, LED lighting is much more broadband, emitting over a wide range of wavelengths. Whilst 'light pollution' filters such as the IDAS D2 will help somewhat, the only real solution is probably narrow band filters.

[Jm1973]

2 hours ago, Seelive said:

Unfortunately, unlike the old orange low  pressure sodium lights that only omit in a very narrow bandwidth which are easily removed by filters such as the IDAS D2, LED lighting is much more broadband, emitting over a wide range of wavelengths. Whilst 'light pollution' filters such as the IDAS D2 will help somewhat, the only real solution is probably narrow band filters.

You mean something like a tri or quad band filter?

[alan potts]

I very recently bought and tried the Optolong L Enhance which is a tri-band filter on my setup here but trust me I am no expert on these filters and there are many better people on site. Now I am in a better situation to being anywhere near Bristol which must be very large now. Yes this did give darker subs though I was looking at the filter from a different view point, IE not how good it was as an LP filter. I sold the filter on after 3 weeks as I did not like the images it produced, sadly I have dumped the data so can't show you what I mean, the image were just not to my personal taste.

I do however feel I may have acted too quick with the sale as I should have tried a mix of with and without.  I am now strongly considering the Extreme dual band filter from them to have another go. Reading the info this will without doubt cut all LP issues as it only allows a pass at H alpha and Olll and basically nothing else.

Alan

[Seelive]

8 hours ago, Jm1973 said:

You mean something like a tri or quad band filter?

Well I consider them all to be dual band but with differing widths of the two pass bands.  I have never used one as I image using an unmodified DSLR.  I suspect they will be OK with astro cameras and modified DSLRs, but an unmodified DSLR has little response to Ha so I suspect you would just end up with green only images.  I purchased an IDAS D2 clip-in filter for my Canon at the beginning of this year with high expectations from what I had read.  In response to another query about filters a few of weeks ago, I posted a couple of wide angle images of Orion taken soon after I had received it, both with the filter and without it for comparison (see https://stargazerslounge.com/topic/364513-light-pollution-filters/).  With the 50 mm lens I had used, I found it gave unwanted fan shaped aberrations around the brighter stars , so it has stayed in its case ever since. It may work better with longer focal length lenses but to be honest I find easier to correct the images for the light pollution rather than trying to colour balance the image to make-up for the missing parts of the spectrum.

 

[PeterCPC]

I also moved on my L-enhance as it did not give as good results as my IDAS D2. I ordered a L-extreme in early September (not here yet) more for hoping I could still image in Moonnlight than anything else as there are always clear nights when it's a full moon.

[alan potts]

On 30/10/2020 at 09:11, PeterCPC said:

I also moved on my L-enhance as it did not give as good results as my IDAS D2. I ordered a L-extreme in early September (not here yet) more for hoping I could still image in Moonnlight than anything else as there are always clear nights when it's a full moon.

Interesting what you say Peter, I feel I may not have given the L EnHance a fair trial and was too again considering the Extreme. I acted too soon and wish I have tried some mixed stacking, with and without. I didn't much like the effect of filter only at all. I am not badly off for LP but I do have a LED glow to the SE from the towns 4 miles away. All other directions are completely clean

Alan