L-enhance with fast systems

[jfrijhoff]

Hi, I’ve been reading that narrowband filters aren’t always suited for fast systems. I’m wondering if anyone can help me assess whether the Optolong L-enhance would be suited for my rokinon/Samyang 135mm at f2.8? I’m using it with a full-spectrum eos 550D.

[Elp]

Just try it. I've used my extreme with hyperstar (f2), the issues will be whether your flats will be good enough to subtract from your image, that and ensure absolutely no stray light hits the lens as you end up with all sorts of strange colour patterns on the image which don't calibrate out, I've had it with the Lpro too.

[jfrijhoff]

That’s the thing, I don’t have it yet, but there’s a second hand that I could buy.

[Elp]

What size?

[jfrijhoff]

It’s a clip-in for APS-c sized DSLR. Don’t have a dedicated astro-cam for now.

[Elp]

It's up to you. It is kind of limited in that you can only use it with emission nebulae targets rich in ha and o3, for those it works great. 

Have you looked on astrobin whether people have used it with that lens?

[jfrijhoff]

That’s a good suggestion, I’ll check astrobin as well, thanks!

[Adam J]

1 hour ago, jfrijhoff said:

Hi, I’ve been reading that narrowband filters aren’t always suited for fast systems. I’m wondering if anyone can help me assess whether the Optolong L-enhance would be suited for my rokinon/Samyang 135mm at f2.8? I’m using it with a full-spectrum eos 550D.

Its not designed to work at F2.8, if you own one try it, but if you dont own one then you will need to invest in a preshifted filter instead.

Its not so bad a situation as with a scope that has a central obstruction as in those cases you can litterally end up with nothing, but most likely you will not be truely getting the full benefits of imaging at F2.8.

https://www.firstlightoptics.com/idas-filters/idas-nbz-uhs-dual-band-nebula-boost-filter.html

Above is that I would recommend. See the reviews and you will note comment on the SharpStar 15028HNT with L-extreem with

Adam

[jfrijhoff]

46 minutes ago, Adam J said:

Its not designed to work at F2.8, if you own one try it, but if you dont own one then you will need to invest in a preshifted filter instead.

Its not so bad a situation as with a scope that has a central obstruction as in those cases you can litterally end up with nothing, but most likely you will not be truely getting the full benefits of imaging at F2.8.

https://www.firstlightoptics.com/idas-filters/idas-nbz-uhs-dual-band-nebula-boost-filter.html

Above is that I would recommend. See the reviews and you will note comment on the SharpStar 15028HNT with L-extreem with

Adam

Thanks Adam, at the moment it’s just a DSLR and rokinon lens, so stuck with clip-in filters at the moment. I did indeed read good reviews in general of the IDAS filters.

[Elp]

You could if you wanted to mount larger ones up front with step down rings but you'll be stopping down the aperture in the process.

I've shot with old lenses at F5.6 fine via this method.

[jfrijhoff]

I’ve come across some good results over on Astrobin using this lens and filter, so I went and got a second-hand, which is on the way.