Orion et al with the Explorer 150PDS

[PeterC65]

Another visual session with the Explorer 150PDS following a slightly frustrating (due to next doors lights) and curtailed (by fog) session the previous night. During this session the sky was crystal clear and next doors had turned off their lights. I stopped only because it was getting late and I was getting very cold.

I’ve started using a Dictaphone to record contemporaneous voice notes and that’s resulted in a much more detailed set of observing notes.

I put the eyepiece case on a garden chair which is the best place for it when observing perched on the stool. I also printed off the Observing List and slipped this down the back of the eyepiece case which held it against the wind and made it easily accessible just by pointing the red torch at it.

I started from park and the alignment was good throughout the session.

M33

With the ES68 24mm I could just make out a faint smudge when observing directly, slightly better with averted vision, but there was no structure and I could only see the brighter core of the galaxy and not its extent. With the ES82 14mm it was no better. This target looks so much better with EEVA!

M45

Looked good with the ES68 24mm but it filled the field of view. I could see nebulosity around all of the primary stars. With the UHC filter the nebulosity was more widespread, covering the whole nebula, but then the stars took on a green tinge. With the BCP 32mm the larger exit pupil seemed to make the nebulosity a little clearer. The BHA 36mm with its wider field of view gave a sense of context and the nebulosity was still apparent (no filter), overall my favourite view of M45.

M42

With the BHA 36mm I could easily see the seagull shape of the nebula. At this scale de Mairan’s Nebula was obvious as a round ball of nebulosity surrounding a star just away from the head of the seagull. This is the first time I’d spotted de Mairan’s Nebula as a separate nebula and after spotting it, it then became obvious. I could also clearly see the Running Man Nebula and the Lost Jewel of Orion Nebula in the same field of view, so the whole Orion Nebula group.

What’s nice about M42 is the way it appears across a range of magnifications.

With the ES68 24mm the Running Man Nebula and Lost Jewel of Orion Nebula remained in the field of view and I could see more detail in the Orion Nebula. The UHC filter improved the view of the nebulosity but diminished the view of the stars (the Trapezium for example).

With the ES82 14mm the Running Man Nebula and Lost Jewel of Orion Nebula were right on the edge of the field of view and not so observable, but the Orion Nebula itself was centre stage. I could see much more detail of the structure and just make out the four main stars of the Trapezium. De Mairin’s Nebula was starting to look a little thinned out. Overall this was the best view of M42 – with monocular vision.

With the ES82 8.8mm the Trapezium was easier to pick out but I was starting to loose some of the wider parts of the nebula.

With the ES82 6.7mm I was concentrating more on the stars than on the nebulosity so better without the UHC filter. I could still only see four stars in the Trapezium, with perhaps a hint of two more, maybe E and I it seems when checking later.

With the ES82 4.7mm the Trapezium stars were even easier to discern and I think I may have been seeing G rather than I.

Finally with the Binoviewer with 20mm eyepieces and the x1.6 Barlow. Quite a sight as the Orion Nebula was framed beautifully and two eyes made for more relaxed viewing and more detail. I’ve been looking forward to observing M42 with this combination of kit for a while and wasn’t disappointed.

Orion’s Belt

With the BHA 36mm all three stars can be see but only just, and really it’s better to just take in two of them. Between Alnilam and Mintaka I could make out the S shape of stars but it came close to filling the field of view making it less obvious that it appears with the refractor and an even wider field of view.

Centred on Alnitak I could see no real nebulosity but that may have been because the star is so bright it may have blown out any nebulosity.

Mars

Just a bright disc, even with the ES82 4.7mm. Better with the yellow filter to reduce the brightness. I could see diffraction spikes from the spider, more like bands the width of the planet. One side of the planet looked brighter and the other side darker but there was no other detail visible. With the blue filter I just got a blue disc and the orange filter darkened it too much. The ES52 3mm just gave a slightly bigger disc. Mars remains disappointing.

NGC1893

With the ES68 24mm the Y shape could be seen at the centre of the field of view, with the arms appearing as quite wide bands of stars. I could just make out some unstructured nebulosity around the centre with the UHC filter.

M35 / NGC2158

Looked good with the ES68 24mm. I needed the GOTO to tell me where NGC2158 was located but once I had been shown I could see the much fainter and smaller star cluster. The side of M35 opposite NGC2158 is in fact quite densely populated by stars as if M35 itself is fading away and this is easy to confuse with NGC2158 (I did initially). What really gives it away is that there is a bright star (5 Gem) on the opposite side of M35 to NGC2158.

M1

There it was right in the centre of the field of view of the ES68 24mm, just a small smudge, but there was no mistaking it even with no filter. More magnification didn’t improve things and I could see no detail. Indeed with the ES82 8.8mm I couldn’t see it at all.

NGC2264

With the ES68 24mm I could see the bright star on top of the tree and two lines of stars coming from it, but I’m not sure I would call it a Christmas Tree. Depending on where you consider the lines to finish it filled most of the field of view.

NGC2170

Just a sparse starfield, even with the UHC filter I could see no nebulosity. One to add to the EEVA target list.

I came in after 2.5 hours, frozen but having completed an interesting session under clear skies with no light pollution.

 

[Ratlet]

That was a busy night!  You got a lot of objects in for 2.5 hours.

I too was disappointed with mars with my closely related 130pds.  I found stacking a moon and skyglow with a yellow filter made a huge difference.  It is still bright but the dark patches have a shape rather than being gage and mushy.  I've tried it under (for me) exceptional seeing and pretty ropey and found the view improved.  I checked on a mars phase online and saw a good agreement between my observation and reality.

I literally ordered the cheapest yellow and skyglow filter from eBay and found it made a huge difference

[PeterC65]

12 hours ago, Ratlet said:

I too was disappointed with mars with my closely related 130pds.  I found stacking a moon and skyglow with a yellow filter made a huge difference.  It is still bright but the dark patches have a shape rather than being gage and mushy.  I've tried it under (for me) exceptional seeing and pretty ropey and found the view improved.  I checked on a mars phase online and saw a good agreement between my observation and reality.

I have the Baader yellow filter which I always use for the Moon and often use for the (larger) Planets. It does make a huge difference but I'm not sure whether that's because of the colour or because it dims the object. I used to have a neutral density filter which just dimmed the object and I preferred the yellow suggesting that the improvement is at least partly down to the colour.

In my visual filter wheel I also have the Baader light blue and orange filters. The light blue has a similar effect to the yellow filter but the blue tinge that it imparts feels wrong. The orange filter does sometimes bring out more detail but it dims the object more than the yellow and imparts more colour.

Not in the filter wheel I have the Baader green filter which has a very similar effect to the yellow filter, and the Baader red filter which I've hardly used because it dims objects too much (it may work better with bigger aperture scopes).

I've bought Baader filters because when I bought cheaper Astro Essentials they were deeper and the depth was variable. One was too deep to go in the filter wheel.