John

1 hour ago, Ricochet said:

How does the Hyperflex perform in regards to reflections, ghosting and scatter? I've wondered about getting one for h-alpha but wonder if that might push it a bit too far. 

I keep swapping mine out with my Pentax XWs expecting the XWs to be noticeably better with regard to the issues that you mention but the differences are really quite small if I'm honest. Having spent the best part of £1K on the Pentaxes I'd love them to be markedly better but I'm really not seeing that big jump other than the AFoV and a bit more eye relief 

There probably are slight improvements at times and on particular targets but, at least for me, they don't jump right out. hence the zoom gets more use than I thought it would.

I did use the zoom with my Lunt LS50 when I had it and it worked nicely. It's also good with the Lunt Herschel Wedge in white light.

10 hours ago, Highburymark said:

Supposed to be unbeatable on axis - but seeing as they have an afov of less than half an Abbé ortho there are compromises.....

Not going to be a lot of fun with my undriven / alt- az mounted scopes

The TMB Supermono 5mm was darned hard work ........

I'm all for a bit of observing comfort these days

44 minutes ago, Mark at Beaufort said:

That is useful information John. I undertake Outreach observing (if covid ever allows me again) and I thought this zoom would be a useful addition to protect my main EPs. I did have a Nagler EP almost ruined by someone wearing eye mascara. I note that I can purchase this zoom for £45.99 with free postage so worth a punt.

I will let members know how I get on.

That was originally why I bought the Hyperflex but I've found that I use quite a lot for regular observing as well.

4 minutes ago, IB20 said:

Hmmm, this has got me wondering if having a zoom EP would be useful for those days of questionable seeing where it could either be used exclusively or help identify the EP of optimum magnification. The Hyperflex 7.2-21.5 seems to be getting a fair bit of love at a very decent price? Is this a continuous zoom EP? How does it compare to the Baader mk IV?

It is a continuous zoom (no click stops). I would say that it is optically about the same as the Baader 8-24 but the field of view is narrower - around 38 degrees at 21.5mm to around 55 degrees at 7.2mm.

It barlows well with the Baader 2.25x Q-Turret barlow to give a 9.55mm - 3.2mm zoom.

More little 'uns

1 hour ago, Deadlake said:

I've shut up shop until Sunday, however maybe clear skies tonight 12-3 am in Surrey area...

Not looking terribly hopeful here

I still have my old Tasco 60mm refractor with it's mount, original eyepieces etc. They date from the 1960's.

Some of my regularly used kit is probably 20 years old now eg: the Vixen ED102SS.

I've owned 3 of the Baader 8-24 zooms over the years. They are pretty good. I tried the Leica ASPH zoom (about £700 new I think !) for a while and that was excellent but I still preferred my fixed focal length eyepieces.

My current zooms are the Hyperflex 7.2mm - 21.5mm and a Tele Vue Nagler 2mm-4mm. I use both of those a lot (the Hyperflex often with a 2.25x barlow to make a high power zoom).

I would not have a zoom as my only eyepiece (that was what the Leica ASPH experiment demonstrated) but they are useful to have in the tool box.

5 hours ago, globular said:

I only have one XW and it was brand new a month ago. It’s cap falls off all the time. Don’t tell me it’s going to get worse over time?

I’m going to get / build a case to store it upright rather than on it’s side to minimise the issue (aka the Louis workaround) while I await a new cap that actually fits (aka the Mark solution).

I've tried all four of my XW's (10, 7, 5 and 3.5) holding them upside down and shaking them quite vigorously. The caps all stayed on. They are easy to pop off and on at night so I can live with the stock ones.

3 hours ago, Ricochet said:

Sorry about that! I guess the best description is that the "hole" in the eye cup must have got wider or rounded over at the top so that it doesn't grip the eyepiece cap at all. 

That's an interesting idea. I have four Pentax XW's, 2 are quite a few years old and purchased used and two were purchased new a couple of years ago. I'll have to try some experiments to see if the caps are looser with some of the eyepieces than others.

On 02/11/2020 at 10:29, johninderby said:

Think I could do with an Astronomik UHC filter for this? 🤔

Not a bad idea

When I get a dark night and Orion is well placed, I'm going to try observing M42 through UHC, O-III and H-Beta filters and sketch the difference these filters make vs no filter, to the principle features within the nebula. I've noted them in the past but I've not been very systematic in comparing the impact of these filters.

Just to add to the confusion, there were two John's in this thread with AZ100's. One of them still has one. Mine were on loan for beta testing.

Very nice !

Will you be imaging with it ?

2 hours ago, Louis D said:

If they were exactly the same length, would 2" filters safely clear the 1.25" barrel?  It would be mighty close.

That was why I had to use the 28mm Baader FT rings. The 14mm gave insufficient clearance for a 2 inch filter. The ideal length would be 17mm-20mm I reckon, just clearing the end of the 1.25 inch barrel.

8 hours ago, Dantooine said:

 

I have also thoughts about putting the extenders on a lathe (Hence the tv instead of the baader rings) and making them exactly the same length as where the 1.25 barrels end. There seems to be no manufacturer that makes the perfect fitting extenders. 

You will need to measure and lathe each eyepiece and extender separately. The 2 inch skirts and the 1.25" barrel sections of the Ethos 13, 8 and 6 are all slightly different lengths, just to make life interesting

17 hours ago, cloudsweeper said:

Sorry.....is there another sort?  😉

Doug.

Well, apparently we visual observers could be wasting our time:

https://stargazerslounge.com/topic/365778-observing-disappointment/?do=findComment&comment=3982775

But I think I'll stick with it

2 hours ago, Rusted said:

Nice instruments John.

The T-Rex needs an offset counterbalance by the look of it.  Berry, offset fork style.
You'll need a large clamp which doesn't mar the surface of the mounting cylindrical section.
With a threaded rod, [stud/all-thread] on the opposite side to the telescope, to carry the counterweight.
Work out the weight of the telescope and its offset to calculate the moment required.
Lead is dense and compact.

What about a black, gutter downpipe clamp in PVC?
They are set up to have a sturdy screw fixing to the wall.
Some are about the right size too...

 

Thanks

The joy of the T-Rex is that it is really solid and steady without any need to counterweight the scope. If a counterweight was needed I would have gone for an AZ100 instead. I needed two of Rowan's 3.75 kg counterweights to balance the 130mm F/9.2 when I used the AZ100 but none at all with the T-Rex and that is one of the main appeals of the latter for me - keeps the overall weight of the setup down by 7.5 kg which is very important to me in my observing circumstances.

2 hours ago, Rusted said:

Patrick Moore's 5" refractor had a Charles Frank mounting.
Recognisable by the spherical housings. It also had a nice, solid pier by the look of it....

 

My secondary school had an 8 1/2 inch Frank newtonian in a dome on the same mount. The very first telescope of any type that I observed with. I was about 12 years old !

This has developed into a fascinating thread.

If I had been able to mount the Istar 6 inch F/12 really well (as per @Rusted's post) I think it would have performed superbly. The best that I could give it was an EQ6 mounted onto a Meade Giant Field Tripod (3 inch diameter steel legs). Even that setup weighed in at getting on for 50 kg when fully assembled. The scope made the usually rather hefty EQ6 seem rather puny

I think a Fullerscopes Mk IV would have been better but I could not find one when I needed it !

My inspiration for a large refractor has always come from Sir Patrick Moore's 5 inch F/12 Cooke refractor:

Back in 2016 I was fortunate to be able to purchase a TMB/LZOS f/9.2 130mm triplet which, although shorter than the traditional refractors mentioned in this thread, was still a long scope for a triplet apochromat and, as In understand it, was designed by Thomas M Back to be a specialist planetary instrument. Even at F/9.2 this scope presented some mounting challenges but with the purchase of a lovely pre-owned T-Rex mount in February this year, that problem is solved and the scope is now delivering to it's full potential.

This may well be the largest aperture refractor that I own for the foreseeable future:

1 hour ago, markse68 said:

I could get one made for you John next time we do a print run- I’ve been making caps in odd sizes for my other eps that didn’t have them like my CZJ orthos . I make them slightly oversize but with 4 little dimples that grip the ep so they stay on but are easily removed (like the black polythene ones you sometimes get)- just let me know a more precise diameter and depth and I’ll see what i can do

Mark

Thanks Mark - that's a nice offer

I'll do a more careful measurement as soon as I get a chance.

I'll be interested to hear how that works out for you.

I use Baader 28mm fine tuning rings with my Ethos 13, 8 and 6 but that is more about allowing a 2 inch filter to be used with them. It's not made them par-focal. The 8 and 6 are (extension or not) but the 13mm and 21mm are someway off (and different from each other as well). I've just kind of accepted that's the way that the Ethos range is. When I want to use par-focal eyepieces I switch to the Pentax XW's.

I've not yet worn out a focuser !

12 minutes ago, Stu said:

Agreed John, I was only mentioning the 5mm to show that very high powers can be reached in the OPs scope without the need for a barlow. The 8mm would be a very handy eyepiece to have.

I agree that they are both worth having. If one is bought before the other, I'd go for the 8mm first

18 minutes ago, timothy4 said:

Thank you Supernova that makes good sense.  The scope came with 40mm and 13mm eyepieces.  I heard some advice to avoid cheap short focal length eyepieces so if I went for a 5mm would make sure it was at a mid price point.

The 8mm will be much more use than the 5mm on most nights. The BST Starguiders are pretty good eyepieces for their cost and are available in both those focal lengths:

https://www.firstlightoptics.com/bst-starguider-eyepieces.htm

That faint smudge might have been the Andromeda Galaxy. Like most things, visually it looks nothing like as spectacular as the images you see of it. It's also a very large object so with the F/10 SCT scope you will probably have just been looking at a portion of it.

Excellent choice for visual astronomy

I need to get a new larger dust cap for the ES 17mm 92 degree. The one supplied fits fine with the eye cup in the rolled down position but I use it in the rolled up position and that means a larger diameter dust cap. I'd prefer not to fiddle with rolling the eye cup up and down as I re-cap the eyepiece. I've been looking out for a suitably sized dust cap but so far not found one. The size is around 64-55mm I think.