Messier 42 with an H-Beta filter

[John]

Just quick post mid-session.

Very nice night so far with lots of winter favourites on show.

I've been enjoying Messier 42 with my 12 inch dob using various eyepieces and various filters. When I tried using the H-Beta filter I noted that a particular feature of the nebula becomes much more obvious than it is with a UHC or O-III filter, or no filter at all.

I've outlined this feature in the image below (not mine I ought to say) in green. I have seen it referred to in some places as the "sail" but also as "shocks". To me, with the H-Beta, filter it stands out as an elongated scalloped wall shaped feature almost as bright as the area around the Trapezium cluster.

I guess that this area of the nebula must be a stronger source of light in the Hydrogen Beta wavelength than some other parts of the nebula so the H-Beta filter makes it "pop" more than other filters.

I wonder if anyone else has noticed this effect ?

 

 

 

[Littleguy80]

Interesting report, John. I looked at M42 with an H-Beta last night. I did notice some structure beyond the normal. I didn’t specifically notice that area you point out but the HB view was very pleasing. M42 always has so much to offer

[RobertI]

Nice observation John, interesting effect, I shall look into Hb filters a bit more and educate myself. I was out observing M42 last night with a special NRH filter (Neighbour’s Roof Heat) which removes ALL interesting detail from the object. 🙂 I’ll post a report later.