New filter: Optolong L-Quad Enhance

[Lee_P]

Optolong will be announcing a new filter tomorrow (10 October 2023): the Optolong L-Quad Enhance. They're sending me one to test, so if anyone's interested I'll write a review once I've given it a good try.

[Fegato]

Strange to call that a quad filter, as that bandpass is more like a LP filter than quad narrowband. It doesn’t seem that different to the L-Pro.

Do you know how they are marketing it?

[Lee_P]

6 minutes ago, Fegato said:

Strange to call that a quad filter, as that bandpass is more like a LP filter than quad narrowband. It doesn’t seem that different to the L-Pro.

Do you know how they are marketing it?

I thought that too. I did ask, but they said that more info is coming tomorrow.

[ONIKKINEN]

Not too different from the L-pro?

 

[Lee_P]

Here's a PDF with more info about this filter: L-QEF New Product Info 20231009.pdf

[VK6KB]

 

The blurb doesnt mention if its more suitable for fast or slower optics. I'd like to try it with my RedCat 51 if poss.

 

[simmo39]

Would be interested on your thoughts when used in anger.

[Elp]

It'd be interesting to see how it differs from the Lpro and enhance. I had all plus the extreme and didn't see a point in imaging with anything less than the extreme on emission nebulae. Still have the Lpro but usually just image with a luminence instead and address LP via post.

[Lee_P]

Ok, first test is complete. LDN 1251 (Rotten Fish Nebula), Askar 130PHQ telescope, 2600MC camera, Bortle 8. 10 hours with no filter, 10 hours with L-Quad. These images have had the same basic processing steps, just so I could stretch them for comparison. If anyone's interested, you can download the fresh integrations here.

 

No filter:

 

L-Quad:

 

No filter / L-Quad

 

To my eye, the L-Quad data is a bit better, but it's not a dramatic difference. However, this is the first broadband light pollution filter I've ever tried where I've come away thinking it was worthwhile using. 

When the weather permits I'm going to repeat this experiment with the Iris Nebula. (Unless anyone can suggest a better target!) And hey, I've actually collected a grand total of 24 hours on the Rotten Fish, so I'll mix up all my L-Quad and no filter data to make one image to rule them all.

[PeterC65]

I'd expect this filter to be most useful with broadband targets such as galaxies and star clusters. For narrowband targets, such as emission nebulae, the multi-narrowband filters (L-eNhance, L-eXtreme, L-Ultimate) are going to be a better bet.

Perhaps some comparisons of galaxies and star clusters with no filter and with the new L-Quad Enhance might be useful? Even more interesting would be comparisons between the new L-Quad Enhance and the existing L-Pro which is considerably less expensive. I suspect it will be hard to tell the difference.

 

[Elp]

I'd try M45, it's so bright you'd be able to see if any signal is being blocked. Veil will also be a good target to see how well the Ha and O3 isolate, but with the Veil I'd also compare it to an lenhance and Lpro.

Edited October 19, 2023 by Elp

[Lee_P]

M45 would be good, but my neighbour's hours has other ideas... I don't have an LEnhance or LPro, so can't compare. Not sure about the Veil, as that's a prime narrowband target. Optolong are pitching the L-Quad as broadband.

[ONIKKINEN]

M33?

Plenty of broadband signal with also emission nebulae that would pass with the filter.

[Lee_P]

1 hour ago, ONIKKINEN said:

M33?

Plenty of broadband signal with also emission nebulae that would pass with the filter.

You may be onto something there...

[wimvb]

Definitely try it on a galaxy and see how it affects colour balancing and colour calibration in post processing.