Incredible transparency

[Davesellars]

Well, last night was a bit of a bonus..  Unfortunately, I was not able to take advantage of it fully...  The small space we have in our back garden is filled at the moment with a pool (for the kids for the summer).  The forecast was anything but good on ClearOutside however I noticed it clearing a touch around 11ish and then looked out again close to midnight to see Jupiter shining brilliantly.  I popped the EQ5 out the back door into a small space with not a huge amount of manoeuvrability (enough South/East direction at least) and popped the Starfield 102ED on it with the binoviewers.  Within 5 mins I was observing...   The scope needed a touch to cool down and Jupiter possibly wasn't showing its best side but some nice detail of the belts was coming through occasionally - the seeing mediocre.  It was enough though using my 18mm BCOs with 3x barlow effect to make a judgement call on the FOV that using 12.5mm orthos would give in respect to the time the planet would be travelling through the FOV until the mount needed a nudge with the slo-mo control.

Anyway, after some time observing Jupiter the sky just kept getting better and better...  The transparency around 1am was off the scale!   The Milky Way was very clear with structure (and this is typically a Bortle 5 site) with M31 easily visible naked eye as well as the Double Cluster,  The area around Deneb in Cygnus was dense in structure.  Truly marvellous!  Stars down to 5.2 magnitude direct vision so ~ 5.5 averted (ish).

M33 first and with the 18mm BCO showed large nebulous blob without structure direct vision.  A touch of averted vision seemed to distinguish some highlight of central structure coming through although it was always on the edge of vision.  M31 next which filled the entire view with clear structure and M32 almost embedded in the cloud.  M110 was surprisingly large with a bright core and extended area.  On to something a touch more challenging for the aperture perhaps with M74 and I could swear I could a faint tiny patch in the 60mm finder...  The 18mm BCO showed it cleanly - it didn't have any real brightness at the core and the galaxy and remained small however with some averted vision I could see a faint area of extension.  Reminded me of a smaller version of M101.  I probably should have tried the 10mm BCO with it which may have got a bit more detail out.

Pleiades was next showing a very vague amount of nebulous activity around some regions which I could not affirm.  The 18mm BCO however showing an incredible amount of sharpness and colour rendition - I really liked the orange / blue double star in the centre of this cluster.  The 32mm Baader Plossl showed a good view getting the entire cluster in.  I closed out with the 102ED on Mars with the 10mm BCO with a 2x barlow.  The seeing still was not that good but I could easily make out a darker shape within the small disc of the planet.

I finished with the 102ED and got the binoculars out (15x70) and scanned around.  M33 was pretty much in your face and M31 filling the view nicely.  I concentrated on the North American Nebula region - still trying to get a view of this!  I am still not sure - it is so difficult to distinguish apart from the density of the stars in this area.  The region where it's supposed to be was particularly dense with a "cloud" but I could not really discern any form or structure.   I spent a good well scanning around the Milky Way region and called it a night close to 3am.   Quite a bonus for a night that was supposed to be cloudy...  Wish it was like that every night!!!

[Kon]

Very nice report and it seems conditions were excellent. I was out last night and indeed the milky way had a lot of structure. I am in bortle 3. I have not managed the NAN without a filter even with my 8" Dob.

[Davesellars]

Thanks!  I think the NaN is probably a mixture of experience, transparency and sufficient darkness - but looks like the UHC / OIII filter will be required.  Other reports seem to indicate this should be visible in Bortle 4 - 5 given the correct conditions with the filter - I think it may be more down to knowing what to look for more than anything.  Hopefully we'll get another cracking night like that and I'll give it a go with the 120ST (for the widest view) armed with the filters...

[Kon]

2 hours ago, Davesellars said:

Thanks!  I think the NaN is probably a mixture of experience, transparency and sufficient darkness - but looks like the UHC / OIII filter will be required.  Other reports seem to indicate this should be visible in Bortle 4 - 5 given the correct conditions with the filter - I think it may be more down to knowing what to look for more than anything.  Hopefully we'll get another cracking night like that and I'll give it a go with the 120ST (for the widest view) armed with the filters...

I only have an OIII filter and it usually make it pop nicely. The only low magnification eyepiece I have is the ES 24mm 68 degrees (x50 magnification and 1.36 FOV) and the NAN completely fills the FOV; when I started I needed to find the edge and then I could identify it by the contrast with the background. Now I know that the OIII gives me this subtle 'lighter' area so I know I am in the right area. The Gulf of Mexico is a lot easier to spot. Like you said, you need good conditions.

[wookie1965]

Really great session and a great read thanks for posting Dave.