LPR Filters

[VIGER]

Hello everyone,

In my quest for better stars photography light polution is an ennemy to beat it seams and for that ligh polution filters exist.

I found these filters: Astronomik CLS Filter Clip in and Hutech IDAS clip in.

Are they worth it? What's your vue?

Thanks

Michel

[Nighthound]

I use the Hutech IDAS LPS-P2 with my Sky 90 II. This filter attaches between the camera T-ring and TAK focus reducer/flattener. It's 48mm in diameter.

Even under fairly dark skies I use it. It's very effective and makes color balance in processing much easier due to the reduced color shift from unwanted light.

I have not used the clip type units that fit inside the DSLR.

[chris.bailey]

I use the Astronomik filter and have a clip in one for when I use a DSLR and a big screwy one for when I use a CCD. Both are very effective though the clip in one is a bit of a pain to get in and out.

I reckon they are of most use when you get to guiding exposures as they extend the skyglow limit a bit.

[VIGER]

Thanks for your feedbacks so far. 1 to 1 match nul. ;)

I use the Astronomik filter and have a clip in one for when I use a DSLR

Is color balance an issue in a sens that you cant work it out with photoshop.
Also I will be using this in the 20D mod. What I undertand also is that I can use it on all my lenses. But I forgot to ask, any other filters outhere?

[Adrena1in]

What I undertand also is that I can use it on all my lenses.

I've got the Astronomic CLS clip-in LP filter, (I find it pretty easy to get in and out), but you can't use it with an EF-S lens - only works with EF lenses. (And telescopes of course!)

I don't use it as much as I should really, because the times I have used it it not only seems to cut out the LP, but it seems pretty good at enhancing some nebulae. I've got NGC7000, The North America Nebula, to appear very red on my unmodded 450D using the filter, whereas it normally appears a faint, muddy brown.

When I get some clear skies I'll try and take some "with filter" / "without filter" example shots if you like? Might be useful to others, or if others could do that with various filters that they own. Just an idea.

[VIGER]

I'll try and take some "with filter" / "without filter" example shots if you like? Might be useful to others, or if others could do that with various filters that they own. Just an idea.

That would much appreciated not only by me for sure.

I'm tempted to buy one.

[Nighthound]

Be sure to ask if the filter you choose is designed for photography usage.

There are many LP filters out there that are for visual purposes only.

[VIGER]

This is what Jerry as to say about them. I found that out searching when waiting for the server to come back online:

Limitations

There are a couple of limitations in using these filters.

In-camera filters won’t work with Canon EF-S lenses because these lenses protrude into the camera body too much and would hit the filter.

Because these filters are interference filters, they won’t work with wide-angle lenses at wide apertures.

Longer exposures, especially at really dark-sky observing sites can be a problem if you are shooting unguided and your mount can not track accurately that long without trailing. More: http://www.astropix.com/wp/

That's interesting to say the least.

[Adrena1in]

There are many LP filters out there that are for visual purposes only.

I wonder if the prices vary depending on use. I bought two screw-fit LP filters for only about £15 each, and I've never used them, but wonder if they're more for viewing. Must try them...I'll try and get out one evening this week.

[chris.bailey]

The Astronimik filter comes in two flavours. One for modded and one for unmodded. I must have fat fingers or just be clumsy as I do find them a bit of a bugger to get in and out.

They do affect the colour balance but I find that the options in Deep Sky Stacker sorts that out. I have only used one attached to the back of a scope but given I have a fair bit of LP in my normal shooting area I tend to always have one in place.

[DSLR AstroMod]

Personally it's the Astronomik UHC for me hands down.
Similar to the CLS, but has narrower band range around Ha, Hb and OIII allowing imaging right through the month even at new moon which is always a bonus and blessing :)
Its an excellent LPR filter too! I have the clip version.

My imaging times have gone from 2 minutes saturated by skyglow, to 10 mins during new moon and still haven't reached skyfog limit yet.

Here's a few images shot through my modded 450D with the UHC filter in place.

http://www.astrophotogallery.org/data/752/IC1396A-crop.jpg

http://www.astrophotogallery.org/data/752/NGC1499-highpass.jpg

http://www.astrophotogallery.org/data/752/M31-darks-flats-crop.jpg

http://i158.photobucket.com/albums/t89/starfighter66/Astro%20Images/ic434-11x5mins-web.jpg

[VIGER]

I assume that these pictures were taken in Hertfordshire, U.K in a light poluted area?

[DSLR AstroMod]

I assume that these pictures were taken in Hertfordshire, U.K in a light poluted area?

Yes moderate to bad LP, about mag 4.5 at zenith, 10 miles from North London and close to 2 large towns, Luton and Hemel Hempstead.

[VIGER]

Pritty much the same situation I'm in. Be cool to have a side by side comparaison but suffice to say it's convincing.
Many thanks.

[Adrena1in]

Did take a couple the other night, but straight up, where LP isn't too bad for me. The moon was out, but the images basically looked a bit red without the filter, and a bit turquoise with it. So I'll wait until the moon's gone and take some low-to-the-horizon test shots.