CLS Filter - is it worth it?

[Veritas]

I see a lot of people using the CLS filter for imaging, what are the pros and cons, are they worth the money  and if so which are the best ones?

Would be used on Canon 550d and Megrez 72.

Thanks

[carastro]

It depends on your light pollution.  If you image in a relatively dark site then you won;t need one.  But they are definitely worth it for LP locations.

Carole 

[Davey-T]

I use an Astronomik CLS clip filter on my Canon cameras definitely gets rid of the orange colour cast, still leaves some processing to do to get correct colour balance.

Dave

[Scott]

The pros are, they work....the cons are, they aren't cheap. for me, worth every penny though . 

[wxsatuser]

If you have LP it will enhance the contrast and give you longer exposures, well worth it with LP.

[Uranium235]

Same here, got the CCD CLS 2" version. Does what its supposed to, and its a good alternative to the Hutech.

[jambouk]

They are effective, but introduce a blue hue to ones image and do block some of the good photons as well as the bad ones, and therefore requires longer exposures (or more of them, or both).

James

[laser_jock99]

Get a 2" fit LP filter instead of the Canon specific 'clip' filters. Way more versatile.

[Ibbo!]

the cls makes it possible to wide field with my dslr from the garden

[jambouk]

The canon clip does give you the versitility of doing dslr widefield though with a standard dslr lens (not all lenses will fit though when the clip is in situ).

James

[happy-kat]

I bought a 2" filter (baader) and use different step rings for it to fit various lenses rather than going for a clip style filter in my Canon. But maybe my comment is not relevant for your small refractor.

[Andy Mitchell]

Filters are very much a  "horses for courses" thing.

A CLS filter will make a world of difference if your light pollution falls in the frequnecy range it rejects. For example if your main problem is the orange glow of low pressure sodium street lamps, you will love your new CLS filter and feel it was money well spent. On the other hand, if your problem is mostly broad spectrum white lighting, you will wonder why you wasted your money on it!

[gorann]

I find that a CLS filter works well on DSO even if I have no light pollution since it brings out Ha and OIII on the expense of some less interesting wavelengths. If you like me have some T tread extenders between your scope and camera you may be able to fit in a T thread CLS filter in your light path. That one is slightly smaller and quite a bit cheaper than a 2" filter and I am able to use it on both my 80 mm apo and 8" Celestron SC.

This is the one I bought: http://www.astronomik.com/en/visual-filters/cls-filter/astronomik-cls-t2-fassung-m42x0-75.html

[Traveller]

CLS filters are worth the money in light polluted areas. For heavily light polluted areas, I use a Baader UHC-s filter, but that filter really block out the reflection nebula. My image of Trifid is almost devoid of the blue reflection nebular because of the Baader filter.

You can get away from CLS filter by using 30 sec exposures or less, but you won't pick up much detail of DSOs.

[DaveS]

I keep an Astronomik CLS filter pretty much permanently in my train. It blocks very little of the NB wavelengths while doing a very good job of blocking my LP, mostly LP sodium and some HP.

[Earl]

CLS are imo the best way to deal with sodium lighting / city glow so it really depends on your location.

[cathouse42]

The canon clip does give you the versitility of doing dslr widefield though with a standard dslr lens (not all lenses will fit though when the clip is in situ).

James

Why not fit a step down ring (if needed) and then use a 2" LP filter? I use a SkyWatcher 2" on a step down in front of my Canon EF lenses with no problems.

Would be nice if LP filters were available in forms such as Cokin etc.

Also, the SW LP filter is very very inexpensive and is surprisingly effective.

Regarding lens fitting types, EF-S lenses are dead in the water, no future, they're replaced with EF-M going forward I believe since mirrorless is the budget future, and nobody with a 1D/5D etc uses EF-S in their right mind.

I use this step down ring..  http://www.amazon.co.uk/58mm-48mm-STEP-DOWN-RING/dp/B0013UTYG2/ref=sr_1_1?s=electronics&ie=UTF8&qid=1432041507&sr=1-1&keywords=58mm+TO+48mm+STEP+DOWN+RING

As long as you can screw a front objective filter on, you can use any 2" (48mm) astronomy filter.

[jambouk]

The lens i use for dslr-widefield has a 77mm screw thread at the front, so one would need a massive cls filter to go at the front. This is why i find the eos clip more versatile - but appreciate this isn't true for others.

James

[cathouse42]

The lens i use for dslr-widefield has a 77mm screw thread at the front, so one would need a massive cls filter to go at the front. This is why i find the eos clip more versatile - but appreciate this isn't true for others.

James

Are these large enough?

http://www.bhphotovideo.com/c/search?Ntt=sodium+filter&N=0

3" x 3" or 4" x 4"

Should cover your lens no?  They are also very inexpensive.

[jambouk]

Yeah they look big enough, but a) do they have the same spectral rejection as the CLS filter, and I don't need one as I have an EOS clip CLS filter

More than one way to skin a cat... Who ever skins a cat other than a taxidermist?

James

[cathouse42]

Yeah they look big enough, but a) do they have the same spectral rejection as the CLS filter, and I don't need one as I have an EOS clip CLS filter

More than one way to skin a cat... Who ever skins a cat other than a taxidermist?

James

Well the purpose is to filter out stray lighting wavelengths. They have some for sodium and Sodium Tungsten.

I don't see why they should not work. They should reject the bad lights, and be optically flat since they are for camera filtering.

You could always ask them.

[Physopto]

Have a look at the astronomik web site. Look for the cls filter transmission versus wavelength graph. You will see that it passes about 450 to 550 nm then cuts out up to about 630nm. After that it passes again. The bit from 550 to 630nm cuts out the annoying light from street lighting.

Derek

[wxsatuser]

Well the purpose is to filter out stray lighting wavelengths. They have some for sodium and Sodium Tungsten.

I don't see why they should not work. They should reject the bad lights, and be optically flat since they are for camera filtering.

You could always ask them.

They reject the light you want as well.

These filters are not really suitable as their transmission is poor, typically 2 to 3 stops increase in exposure.

I stand to be corrected but they may not increase contrast on night sky images and would let airglow through as well.

Money well spent would be a CLS or one of the IDAS ones,.

If you have LP and want to increase exposure times get a good one.

[Earl]

somewhere is the darkest corners of this forum i posted a comparision photo shooting directly at a street light of the clip CLS, the difference is very pronounced.

[Earl]

here.

http://stargazerslounge.com/topic/81054-astronomik-cls-eos-clip-filter-test/?hl=+astronomik