chiltonstar

49 minutes ago, John said:

I've managed to see E & F occasionally with my 100mm / 102mm refractors (needs very good conditions with those), quite often with my 120mm and 130mm refractors and they are pretty obvious all the time with my 12 inch dobsonian.

Getting the magnification right seems important to getting these stars - I find around 150x -200x to usually be the optimum. F is harder then E because it is close to the brightest of the 4 main Trapezium stars.

 

Agreed. I use a zoom ep most of the time now for doubles, which I find ideal for the Trapezium. Low mag shows the E star best, then winding up the mag splits the F star from its companion.

Chris

I've been using the 127 Mak (not the same mount) for about 12 years now. In my opinion, essential accessories include a dew shield (DIY works well) and something better in the eyepiece line than the Skywatcher offerings. Two that I use most with my scope are the Hyperflex 7.2 - 24mm zoom, plus a decent 25mm wide field eyepiece such as the X-Cel (I use this one, but there are many others). The zoom performs well at the higher mag end where the limited field of view doesn't matter so much, and the 25mm gives you good views of easier galaxies and other DSOs.

Chris

Yes. The SkTee knobs undo with two hex bolts, the flexible cables have one knurled knob. The shaft diameter is the same.

Chris

5 hours ago, John said:

Isn't H Beta the filter of choice for the HH neb is is that a mistype ?

 

It was blue, so yes.

Chris

33 minutes ago, Stu said:

Well done @chiltonstar, a pretty cracking session! I wouldn’t have considered the 180 Mak as a prime candidate for spotting the Horsey, but it obviously worked. Was that unfiltered? Great result either way 👍

Unfiltered. When I tried with a borrowed H Alpha filter, the attenuation was a bit too much bearing in mind the small aperture.

My location aka garden is 20.7 mag according to Clear Outside. In effect, looking S is straight onto downland and fields.

Chris

1 hour ago, John said:

Great report and results Chris

I've not waited up late enough for Sirius to be on view as yet this winter so I've that pleasure still to come, I hope.

To get the Horsehead AND the Pup in the same session is pretty special

 

The HH needs a lot more aperture really to get a good view - it looked very nice when I saw it through a 30 inch!

Chris

Although it was brilliantly clear here last night, I wasn't too hopeful about doubles because Sirius was twinkling quite a bit. However, after letting the scope reach equilibrium on Castor, I moved to The Trapezium which was very clear, with E and F easily visible and the nebula background almost too bright.

The Sigma Orionis group was a joy as ever, and the fainter companion very clear at mag 12. I noticed that many of the doubles around Orion with fainter companions were very obvious - clearly the transparency was truly excellent. More in hope than expectation, I tried the Horsehead which was just visible when in my lower right field of vision (averted). Not as good as the images, but clearly visible.

Just before I packed up at 01:00, I tried Sirius, again not expecting too much even though the seeing had improved a lot. The Pup was easily spotted trailing the primary across the field - probably the best I've ever seen it with the 180 Mak. Although Sirius was scintillating, the Pup appeared stable between the spokes of light. Oh joy!

Chris

Ditto in Oxfordshire, although I did manage to spot Venus last night through a hole in the cloud before I froze to death...

Chris

Bearing in mind the number of stars that are actually multiples (50% has been quoted) I think this is a really worthwhile project - mapping a small area like Lyra and listing the visible doubles for your scope/eye combination.

Chris

I have a venerable old 102mm f13 from 1980 'ish. I bought the achromat objective from Vixen and made a tube for it. It still gives wonderful views of doubles and the planets, even though it is a bit cumbersome. Pic is of it on my Vixen SP mount.

Chris

Some more images of the minimak with a Baader helical focuser fitted, also a reverse lightbeam image (focused) indicating that the true aperture is close to 65mm and the % obstruction about 37%.

Chris

Yes, mine has a 42mm male thread with a 42f and 48m locking ring or adapter. The Baader focuser has a 42f and 32f connection on the base.

Chris

20 hours ago, johninderby said:

Glad to hear you are as impressed with this bargain scope as I am.👍🏻

I used a Sybony Moon & Skyglow filter which works surprisingly well and in keeping with the budget theme. Definitely improved lunar views.

This is the M48 to T2 adaptor. Then just use a standard T2 to 1.25” adaptor. One thing to note that the opening in the back of the scope is a mm or two smaller than a 1.25” eyepiece barrel so get a 35mm or 40mm T2 to 1.25” adaptor.

https://www.harrisontelescopes.co.uk/acatalog/m48t2.html#SID=1664

 

I found that the Baader helical focuser fits directly to the thread without an adapter. Good because it will give me fine focus as well. 

Chris

I added one to my mini-stable after reading John's post above. Very impressed! I tried it out on a few well-known doubles last night when the sky cleared and before the mist.

It actually split Polaris, Rigel, showed the A to D stars in the Trapezium, showed diffraction rings around the Castor pair, and gave a half-decent view of the Moon, all with the supplied zoom. All I need to do now find an adapter that will take 1 1/4" EPs.

Chris

7 hours ago, Mr Spock said:

 

We are all in this together 

I was trying to raise the issue (in my usual unsubtle way) of why doubles and variables don't have their own sections  as they do on some other fora. Rev. Dawes would be turning in his grave (once every 20.5 years).

Chris

14 hours ago, John said:

Good to see this section in the observing part of the forum now - makes a lot of sense I think

 

Can get swamped by the variable star community though............☹️

Chris

Nice! What scope?

 Chris

I find it very evening dependent. It is easier with my 180 Mak than my 80 or 100 mm fracs, although I've seen it with all three scopes and a 127 Mak on the right evening. I've tried imaging it and although the Pup does show up well, the image is nothing like the eyepiece view because the camera averages the scintillation that you see by eye. These three close doubles were imaged with my 127 Mak,- both the Pup and Zeta Her are each difficult in there own way, Polaris much easier:-

Chris

I have one - they are nice scopes, and very sharp. Mine will readily show the craterlets inside Plato (your 4th frame) which is a nice test of resolution.

Chris

Some more for when/if the cloud ever lifts.....

Chris

9 hours ago, Stu said:

This is a screen grab from a video I took quickly last night. Nowhere near as good as the view, but at least you can see Ganymede.

 

 

Better than my view! As the transit progressed, Jupiter dived into some trees, so I had to head off with my ED80 on a portable mount into a field to follow it!

Chris

With warm nights albeit with some haze, I spent a couple of hours two nights ago revisiting Neptune and Uranus as Jupiter had already set behind a line of tall ash trees. Both N and U were well clear of trees, and chimneys but not the occasional cloud or expanded vapour trail unfortunately.

Uranus (x270), a beautiful featureless pale blueish-green ball with three moons visible, occasionally two, the haze worsened as the evening went on,

Neptune (x270 and x350), small bright blue globe (clearly visible as a planet even in the RACI) but unfortunately too much haze and sky brightness to see Triton this time. I switched backwards and forwards between U and N to compare the colour and size of the disks - to my old eyes, Neptune is really very blue cpd with Uranus which literally pales by comparison.

Using my diy azimuth circle and a Wixey certainly made finding Neptune easier to find compared to previous times when I've used star-hopping.

Chris

I always see it as greenish lilac when the sky is very dark. When there's some haze and light from sodium streetlamps is being back scattered, it just looks greyish. Should be magnificent in a 12" dob!

Chris

A nice result - good to see Enke showing!

Chris

22nd Sepember the GRS was nicely positioned when Jupiter was between a neighbour's chimney and trees. 180 Mak, ADC, AS1224 processed in AS, PS and then derotated.

Two nights before (20th), I tried to capture the Io and shadow transit but the seeing was so poor, I've only used some of the AVIs - hence the jerky animation. In clear moments though, the shadow was pin sharp and Io itself could be seen as a buff disk to the right of the shadow.

twice the aperture and a better climate would definitely help........

Chris