Highburymark

On 04/02/2023 at 21:44, Louis D said:

The Baader Scopos Extreme 35mm is quite sharp at f/6 edge to edge, and sublimely sharp in the inner 50%.  It has tighter stars there than many of my premium wide fields.  The downside to it is how big and heavy it is.  Weight wise, it slots between my 12mm and 17mm ES92s.  As such, I don't need to rebalance my scope when switching among these three eyepieces.

Would be interested to see any pics you have of the Scopos Louis

On 05/02/2023 at 14:42, JeremyS said:

This little beauty has given me some of my best ever views of Mars. Using my Tak FS 102 during  the perihelic opposition of 2003 when the planet was almost overhead from my garden in Singapore.

Pentax XP 3.8. It is only 1-inch and has tight eye relief. Stupidly I sold it about 15 years ago when I all but stopped visual observing. A couple of years ago I bought another one from Japan. Long out of production and rare on second hand market 

Very nice Jeremy. There’s one for sale at APM in Germany for a considerable sum - 330 euros or thereabouts. First one I’ve ever seen for sale in Europe. Just looked it up and the 3.8mm appears to have 5 elements in 3 groups (same as 5.1mm XO), though the other XPs have 6/5 configuration. And like the XOs, the shortest FL XP actually has more eye relief than the next shortest. Yours apparently has 2.7mm ER, though the 8mm XP only has 2.1mm. 

Entering the murky world of microscope eyepieces can be a little daunting for astronomers. You have to familiarise yourself with complex numbers and names (what on earth is a pl-10x/18 444132-9901?). You have to deal with 30mm barrels - 1.7mm less than 1.25”. And then you have to work out where to buy them - virtually all the best and most affordable models usable for astronomy must be sourced secondhand from eBay, or the many dealers in pre-owned microscope gear. But it’s worth the effort. The three binoviewing pairs I have are exceptional, easily outperforming my long focal length astronomy eyepieces. First - Zeiss OPMI, based on an Abbé ortho design, were made for medical operations. Then I have two pairs of Leica HC Plan S, with different AFOVs, which I understand are revised Konigs. Hunt around, and you can find excellent examples of Leica HC Plan S 10x/22 for £200 upwards, less than a pair of TV Plossls. Best place to start researching is CN - there are a number of long threads there. Most pairs are the equivalent of 25mm, and between 40-60 degrees. So they are specialised tools. But when people are paying thousands to buy a pair of ZAOs, these offer a much more affordable route to eyepiece nirvana.

Spectacular - fantastic capture and thanks for posting

Ok got them - well done on some great captures! 

How do I access your screenshots Nigella?

Very nice Peter. The Lunt 35 etalons do seem to have been mostly excellent, but I didn’t know they were compatible with PSTs.

Wow - spectacular - it’s gone now

5 minutes ago, LDW1 said:

Is the OP getting the info they are looking for ?

Not from you they’re not.  I’m out.

26 minutes ago, LDW1 said:

Were you using a Baader Solar Film filter or a Solar Wedge ? In what way was it better ? I find that with anything over 80mm the glare causes me to use a variable polarizing filter or a no.56-58 green filter and the constantly changing air currents distorting are more noticible in an over 80mm scope.

Baader wedge. Binoviewers, pairs of orthoscopics, GPC and Barcon, mostly. Used same kit for all my scopes. The 80ED was great for 80-140x in mediocre seeing, but the extra grasp of a well figured 4” really delivers WL definition when conditions allow. I tend to do white light at 160x-240x now. You need minimal levels of SA and CA to resolve penumbra detail and granulation to provide sharp views at those powers. And in my environment, you get a lot more out of  a 100mm scope.    
Seeing is different everywhere - what works in one place might not work in another.

45 minutes ago, LDW1 said:

I have owned an 80mm Equinox with its FPL53 glass and I would love to have a Starfield if I was younger even though I have an NP101 and a half dozen other good refractors, some over 30 yrs. old others newer. That Equinox will hold its own with the best of them save for the 101. Its a nice, nice very capable scope and maybe better for solar WL than most larger refractors, 80mm is a sweet spot for many solar astronomers.

I had an Equinox 80 for a long time. Excellent scope, but I saw a considerable improvement in white light views when I moved to a slower 4” apo.

I haven’t read this whole thread, but from reading Neil’s first post, I’d say go for the Starfield. It will do everything you want it to do and more, and will be a significant step up from the F/6.25 Equinox 80, particularly if you enjoy solar. If money’s not an issue, then go for an FC-100. Wonderful scopes. But, much as I loved my DC, I’d be just as happy with any of the excellent FPL-53 4-inchers available these days, from the reports I’ve read. 

I use mine visually - but only for night vision, with magnifications rarely above 30x. Apart from the fast speed, its main strength is showing vast swathes of the night sky - so it’s perfect for imaging or viewing large nebulae with night vision. I’ve had a few glances (during the daytime and once at the Moon) with a traditional eyepiece (Tak TOE 4mm for around 100x), and the views are surprisingly good for an F/3.3 scope. But that was more to test the eyepiece’s ability to handle fast optics than establish the Epsilon’s visual credentials. Of course it also has an ED corrector which significantly reduces aberrations, and the owner’s manual does in fact include a section on visual, but much as I love the scope, I can’t imagine using it as a serious visual instrument, particularly for high power work on double stars. 

Didn’t take any photos, but yesterday was very busy. Widescreen, FLO (and to a lesser degree RVO) stands dominated proceedings on each floor - all three now pushing their own in-house  telescope ranges. Nice to spend some time with the night vision contingent - including Peter and Steve in this thread. 
 

5 hours ago, Alan White said:

I purchased a Lunt 40 Ha last November and had an issue with the helical focuser, its didnt focus.
Was replaced under warranty, the new one is very nice.

What I have done is add a Baader ultra short t2 to 1.25" EP adaptor and one 5mm parfocalising ring to get the focus much easier,
this uses less of the helicla length and keeps things more solid.

As it was…

Image wise, its a nice but small as expected image, lots of detail when the scope is focused correctly and the tilt is set,
takes a while to get used to how this works, but the detail on my one is very good.

With the adaptor and ring fitted..

I use a Japan Made Vixen zoom on this scope as was suggested to me and it works very well indeed.

Very impressed with this scope to date.

The Badder item I used…

Oh and no filters added in, the inage is very good as it is.

Looks great Alan. I had to send my old Lunt 50 back to Bresser in Germany to sort the helical focuser, which had jammed tight. I think the quality has improved since then. But one option - to avoid using the stock focuser too much - might be to use a Baader clicklock 1.25”with fine focusing diopter adjustment.

It’s actually an ED refractor - since Lunt went modular they’ve stopped using achromats - though I think the 60mm is FPL-51 rather than 53. So CA should be pretty well controlled at F/7. I have an F/6 60ED which is a decent all-round scope so the Lunt should be too.👍👍

On 18/01/2023 at 22:01, Sunshine said:

Just beautiful! you simply cannot get a more rewarding grab and go, and you are right to enjoy it on cloudy days, it looks wonderful on that mount.

I agree. 2.8kg makes it the lightest 4” apo on the market. Just to give an idea of what 20mm more aperture means in size, here’s the DC next to a TSA-120 - itself a light triplet at 6.7kg - but two and a half times heavier than the DC.

The 3mm Delite is a fine eyepiece - you’ll love it. Nice 62 degree field and super comfortable, so you can remain relaxed over long sessions. As good as any Delos or XW.

On good nights, however, the TOEs will show quite a bit more detail. I wish I knew more about the optical design (six elements, so far from minimum glass), but they are supremely capable planetary eyepieces. So the 2.5mm would make an ideal, if indulgent, companion to your Delites.

I always enjoy Astrofest - should be lots to see this year. Tough on the organisers and exhibitors that the rail strike coincides with the opening day. But I wonder if there might be a modest post-Covid bounce after so many people were introduced to the hobby during the pandemic? 

The image of the night sky you posted shows signs of astigmatism, but it’s difficult to diagnose the problem without more images - as Adam says you need more diffraction rings on both sides of focus, and the artificial star placed further away. You might need to use a more powerful eyepiece with such a large scope too. 

Great shot! 
And those spots are spectacular.

Just noticed you have a Quark - so it definitely sounds like a temperature issue to me. Every Quark is different. There are a couple of reports I’ve read by owners who say they don’t even turn the heater on in warm weather - the filters operate best without. Sounds like yours takes time to reach optimum heat.

Can’t say I’ve seen this effect, but Peter’s suggestion about the etalon warming up sounds the most likely explanation. Don’t know what set up you have, but the mica type filters (Quark/Sundancer/Solar Spectrum etc) are obviously very sensitive to temperature, so if the in-built ‘oven’ is taking a long time to reach the required temperature, it would certainly result in the gradual improvement in detail you are seeing.   
If you have one of the  Lunt/Coronado solar scopes, it could be the temperature of the blocking filter that is affecting detail, particularly at this time of year. Lunt actually sells a heater to keep the blocker warm in cold weather, otherwise it won’t operate effectively.

Very sorry to hear this news. I don’t think there was anyone on this forum more knowledgable about how to make one piece of astro equipment work with another. He was a one-man help desk to so many members, myself included. Not only would he always know the right part or adapter to use, but he’d also know where to buy it at the best price. And then - as others have noted - there were his own mods. Within hours of receiving a new scope, it would be adorned with new accessories and often very simple upgrades which inspired me on more than one occasion. A great loss to SGL.

1 hour ago, wesdon1 said:

My goodness @Stu !! That looks like the speedometer on my off road motorbike after a day of racing around my mates farm on it!!?? haha! Joking aside, what I really struggle with, is how in God's good name does dirt and grit find it's way IN BETWEEN two tightly fitted Objectives!!?? HOW!!?? Incredible!! 

I can only presume that the gap between the doublet lenses is not fully sealed off to aid with temperature control? Glass expands and contracts in changing temperatures, so perhaps a small opening helps glass keep its shape?