John

3 minutes ago, Starwiz said:

Would parallax matter at infinity?

John

Probably not. It was just a guess. Maybe I picked the wrong term. The tube design has changed though to accommodate the larger optics so I was simply wondering if the design and positioning of the finder mount might need to be adjusted slightly to take account of that. The RDF itself has a reasonable degree of adjustment in azimuth and altitude so for it not to be possible to get it aligned with the main scope, the mounting rail on the scope must be some way off of alignment.

@jetstream If there is simple a mod to sort it out then, yep I can overlook it, provided that the optics are decent. If the solution is that the owner needs to invest in a replacement finder at, lets say, £30 cost then that's a scoop out of the astro budget that might hurt if you are on a tight budget.

Mind you, the Celestron Astromasters have been supplied with truly awful finders for quite a few years and Celestron / Synta have not done anything about those 

22 minutes ago, Dannomiss said:

For my first couple of weeks, not have that RDF lined up has been pretty frustrating locating things in the sky

I can understand that. I find that I need to have the finders on my scopes very precisely aligned with the main scope views to aid the finding process. Aligning along the scope tube is very hit and miss !

Mostly miss ......

Although a small part of the scope, it is a pretty important one. If it is a design problem I'd like to think that Skywatcher would put it right.

I'm bortle 5/4. So that makes a difference to the finding arrangements, I can see that.

I guess it is possible that the moulded finder bracket (which is an integral part of the upper tube assembly I believe) is not aligned properly - ie: a design issue ?

Here is another guess - they used a similar pattern to the 130 but did not make an adjustment to allow for the parallax effect that the larger diameter optics and tube would create ?

Just a guess though ....

2 minutes ago, Pixies said:

Have just moved to using a RACI. I find the disorientation of the reverse image is worse for a finder than the actual scope image. The RACI finder is a great upgrade - BUT it's very hard to use a RACI to find the starting point. 

With a straight finder, I keep both eyes open and align the finder to the starting point. You'll soon be aligned and know where you are pointing. But with a RACI, it's very hit and miss. A Telrad or Quikfinder (or even a red dot finder) will help with the initial alignment.

You went for a 60mm RACI I seem to recall ?

I actually find a 30mm RACI easier to use than a 50mm as the sole finder on a scope because it shows 6 degrees of sky and does not swamp the field with stars.

On the scopes I have a 50mm RACI I usually have an RDF or similar as well just to get straight to the right area of the sky quickly and easily.

I had a RA but not CI once by accident (mis-described by the seller). I didn't get on with it although it actually worked OK.

I find RACI works for me. I guess I like the finder view to look like the star charts I use and also the illuminated reticule finder, if I am using one alongside the optical one.

I seem to be able to make the switch to "scope view" when I look through the eyepiece.

It's all about personal preferences I guess

1 minute ago, parallaxerr said:

But I guess this comparison is in the same scope, correct? - The 40mm in the Tak would produce a smaller exit pupil, thus I assume darker sky background than the 31mm Nagler in the Vixen.

Well it does not seem to work like that in practice

44 minutes ago, andrew s said:

But, what if you used a 43mm eyepiece (assuming I did the sums right) with the F/9 to match the magnification? 

Regards Andrew 

The background sky would not be as dark with the longer focal length eyepiece. I have some light pollution here and that really makes a difference.

I do have a 40mm eyepiece with a 70 degree AFoV (max field stop for the 2 inch barrel) so I can see the above very clearly when I compare the views of the Veil Nebula with the 31mm Nagler, the 40mm SWA and indeed the 21mm Ethos which shows a little less sky but darkens the background sky even more.

Also certain exit pupils are more effective when using O-III and UHC filters.

I think I would need to move to the 3 inch format to get an AFoV that is large enough to show 3.8 degrees with the F/9.

These are quite safe and work well:

https://www.firstlightoptics.com/solar-filters/astrozap-baader-solar-filter.html

15 minutes ago, ScouseSpaceCadet said:

.... I suppose I could try complaining it's lighting up my youngest's room.

 

That point worked for me as well. I sent them some photos of my daughters room with the light coming through the window even with the curtains closed. A shield was fitted to the offending light within a week.

I'll just give one example.

I have two 4 inch refractors - a Vixen ED102 with a focal ratio of F/6.5 and a Tak FC100-DL with a focal ratio of F/9.

With my Nagler 31mm eyepiece the Vixen will show a true field of view of 3.8 degrees. With the F/9 the true field with the same eyepiece is a degree smaller.

When I want to see the whole of the Veil Nebula in a single field of view, the F/6.5 will do that comfortably but the F/9 won't get near it.

The 130 made the split of Beta 648 that much easier although I didn't think the seeing last night was quite as good. I used 300x - 375x but the secondary was visible from 200x upwards.

I got suggestions of a split on Antares but that one is so low down that it throws up a whole lot of it's own seeing issues !

I didn't stay out too late last night so no planets.

Best of the session was Lambda Cygni which I think is a touch under an arc second currently. Last night at 375x it was a tiny "snowman" with a thin belt of blackness around his "waist" that flickered in and out of view as the seeing varied.

Pairs such as Delta Cygni are a piece of cake with this scope

I don't find counterweights are needed with my 100mm - 120mm refractors. Above that (about 8kg) and they do help smooth the motions. The Giro Ercole (for example) needs counterbalancing a lot more than the Skytee II does.

Planets are never going to "fill the field" with a scope no matter what magnifications are used.

I produced this Powerpoint presentation a while back for my astro society which attempted to show what things actually look like through a scope:

telescopeviews.pptx

What you actually see with a scope will vary of course and the darkness of the skies will make a difference on the deep sky object, but it gives some idea I hope.

Its not a good time to try and observe galaxies - it does not really get dark at all.

Even when they can be seen, galaxies just look like very faint, and often small, patches of hazy light. Any light pollution or moonlight really washes them out.

Stars still look like points of light even with a scope and lots of magnification. They are just too far away to be seen as anything other than that. You just see more of them when you view with a scope.

The best deep sky objects to look for at the current time are open and globular star clusters which are much less affected by light pollution and the lack of darkness at this time of the year.

There are also some decently bright planetary nebulae on show. The Ring Nebula in Lyra (small so easily overlooked) and the Dumbbell Nebula in Vulpecula, which is larger and should be noticeable with the 25mm eyepiece. Dark skies help with those as well but they can at least be seen.

These are chinese clones of the Japanese Widescan ultra-wide eyepieces.

Even the Japanese versions, which cost a lot more, were not too well corrected in F/8 or faster scopes.

For £30 or so they give you an idea of what an ultra widefield is about if you have a slower scope but I would not pay more than that for one.

It's not you, it's the solar cycle:

https://stargazerslounge.com/forum/207-observing-solar/

There have been a few outbreaks of spots over the past few weeks, but very sparse. Over time, it will get more active.

SGL and UK Astro Buy & Sell are the two best places to look for used astro equipment I think.

The Tele Vue Delos are excellent as well but do cost a fair bit more than the Pentax XW's or Baader Morpheus.

The main thing when they do come up for sale is to be quick off the mark. They tend to get snapped up quickly if the price is reasonable.

Good initial report Chris.

Interesting that you had issues with the finder - other early adopters of this scope have found something similar:

I think Louis is about right here in the UK as well.

The scope is a very early Orion Optics newtonian on one of their early equatorial mounts.

It is the sort of scope that someone who knows scopes well might buy for a relatively low cost as a refurbishment project.

It has some potential but does need quite a bit of work.

I can list the focal lengths that I find the most useful with my 12 inch F/5.3 dob - focal length 1600mm:

- 21mm

- 13mm

- 8mm

- 6mm

- 5mm

With the longer focal length of your scope you could probably do without the 5mm.

Just have to decide what the best ones that you can afford are now

The most important thing is to make sure that your finder scope is as accurately aligned with the view through the main scope as possible.

Don't assume it is out of the box !

That result looks good to me Neil

I can't really help though because I'm at a similar stage with astro photography - very 1st steps !

I'll be keeping an eye on this thread to pick up some tips myself, if thats OK ?

Is this your first scope ?