sorrimen

54 minutes ago, Stu said:

This site on the South Downs is pretty good. Bit of a bumpy track up to it but a good horizon to the South, albeit some light pollution from the coastal towns. Much closer than some alternatives though, and pretty dark.

Thanks so much for the specific recommendation. If it was a common thing/just for one night this would be exactly where I would be looking. Given that I’ve convinced them to do a camping trip and they’re willing to go far like the lake district, do you not think it’s worth getting to an even darker spot? I’ve got basically no experience with low bortles so I’ve got no idea how much better somewhere like exmoor/lake district would be compared to  the South Downs. Assuming this is my only chance at a darker site for a while, what’s your take?

4 hours ago, woldsman said:

Absolutely - clouds encounter hills, rise and condense (although a lot of the water in the lakes must be melted snow and ice). Wind and the clouds brought in by the westerlies other issues but better than light pollution, at least. Going further inland to the Northumberland national park looks a better bet - that’s where Kieder observatory is situated. 

Hmm yeah I anticipated some orographic rainfall but had hoped there would be areas that could avoid. Northumberland looks great but I think may be just a bit too far to convince my friend to drive sadly. 

Hi all

Hoping those of you in the UK can share some experience and expertise with me. For those of you in a hurry, the short question is where is the best dark site in England and Wales? 

Now the slightly longer version. I live in the outskirts of London in a bortle 7/8. I purchased my 8” dob about 6 weeks ago and would like to get to some darker skies. The caveat is that I don’t drive. I’ve managed to get my friend excited and on board to camp out somewhere to get a couple good nights with the scope in darker skies. So far, we’ve thrown about the idea of the lake district. My question for you guys is what you would say is the best dark site in England and Wales, or even better a little ranking list of a few dark sites! Another factor is weather, so if you guys have experienced, for example, the lake district always being too cloudy then this would be great information to have. Additionally, I haven’t looked into parking and places that allow tents etc. so any information regarding logistics like this would be valuable. One final point may be the interest of the place. As I’ll be with two friends who enjoy the scope, but likely aren’t as interested as I am, somewhere like exmoor may be harder to convince with than somewhere like the lake district, as during the day there’ll be more to see etc. 

Apologies for the wall of text, and look forward to any responses!

Ross

P.s. how do you guys go about planning trips a long drive away i.e. weather checking and moon cycle etc.? Any advice is strongly welcomed!

3 hours ago, Sunshine said:

To me, that secondary looks pretty well centred, more importantly are you happy with the views? issue is that once you begin adjusting the secondary (unless you're glaringly off) it is really easy to make a mess of the whole thing. If it were me I would not split hairs especially when it comes to the secondary as its position can be easily messed up, adjusting for one angle usually affects others and it becomes a pandoras box situation. Just my opinion but I would gauge using a star test and whether or not things look sharp through the eyepiece on a night of decent seeing.

Thanks for your response. I guess you’re right actually, I’ve gone against all that I’ve read and am chasing absolutely perfect collimation, rather than what I’m happy with. I’m loving the views so can’t really complain!

Hi all,

First off, hope this is the correct place for this sort of post. Anyway, I’ve only ever collimated my 8” dob using a collimation cap and as a result my secondary isn’t quite right under the focuser. I was just wondering if anyone knows what sort of effect this will have view-wise? Seeing as everything else is collimated as perfect as I can get it, does this actually have any real effect? I’ve added some images below. As you can see it’s not wildly out of place but enough that after a second look it’s clearly closer to the top in the picture than the bottom. Thanks!

Ross

15 hours ago, OK Apricot said:

Just seen this. For what it's worth, these are single 8s exposures on an A52S through a Skymax 127 (I forget the EP used), just tweaked a little with the phone editor. 

Wow these are incredible and pretty much what I’m after. I’d have to guess that this would be a bortle 5/6 at the very brightest no? Samsungs seem to blow iPhones out the water when it comes to astrophotography usage. 

That's great advice all, I'm actually yet to look for any clusters yet so this should be a nice little challenge and something to look forward to. I've snapped a couple pics of andromeda and M51 (only confirming it was M51 about two days later as it was my first DSO) and as you say there is some blurring, though from a bortle 7/8 it could be worse. 

Also would be thrilled if you tried it out too Xilman! I coincidentally go to university in Cambridge so I imagine we'll be observing from a similar area some of the time.

Hi all,

So I've recently acquired an 8" dob and have got some decent planetary and lunar images just using my phone and a phone mount. My question today is whether I will be able to get any sort of detail out of DSOs (specifically galaxies) by using 3-5s exposures with my phone. Given that my dob is manual, my strategy would be to realign the DSO each shot or after a couple shots so I could somewhat stack the target itself. Would I need so many shots that field rotation will mess everything up/is an iPhone 12 camera just too poor for DSOs? Let me know what you think and whether this challenge is even possible.

Cheers

Ross

P.S. I'm sadly well aware that proper astrophotography needs proper kit, but I'm looking to push the boundaries for what I own and challenge myself, rather than purchase further accessories.

On 10/06/2022 at 20:33, Don Pensack said:

I have had eyepieces for >20 years that I sold that looked brand new.

I clean them by:

1) blow off all debris to avoid scratching.  I have an electric blower (no propellant or oil) that blows just about everything off.

2) I add 1-2 drops of fluid to a Q-Tip, and, while the Q-Tip is wet, make a spiral pass of the entire lens surface, starting in the center, then quickly flip the Q-Tip and repeat with the dry end to mop up the residue.

3) I quickly grab a 2nd Q-tip (cotton only, no additives) and, moving from edge of lens to just past the center of the lens, rotate the eyepiece under the Q-Tip until the whole lens has been brushed twice.

I then flip that Q-Tip to the clean end and repeat the spiral pass.

 

When done, no streaks, no residue, and a clean lens.

 

One way you know the lens is very clean is that the resistance to the movement of the Q-Tip on the lens disappears during the process, as if the lens is teflon coated.

 

This is great, thanks so much! Followed this for my final mucky eyepiece and it worked a treat. 

3 hours ago, munirocks said:

All of the above is good advice but I will add...

I use a strip torn from plain Kleenex - not just any tissues but real Kleenex - wrapped around a cotton bud, using the cleaning fluid to help the strip stay wrapped. Use the side of the tip, never end-on, with practically no pressure, the way that Italian picture restorers touch a painting. Using the side helps prevent your own sudden twitches  from putting undue pressure on the lens (which is where I would worry about lens pens which are used end-on).

Change the tissue strip often. If the lens is dirty I might go through ten strips. If there is a stubbornly dirty area RESIST the temptation to push "just a little bit harder". Use more swipes -- not more pressure. 

To get rid of sleeks I almost always have to do the final polish using distilled water from a ready source -- my breath.

I think I was using far too much pressure, but didn’t seem to damage anything I hope. That last tip I was considering but figured it was bad to do after cleaning. Next time I’ll try it.

12 hours ago, bosun21 said:

I just wanted to check that when you say you let the Baader wonder fluid dry, that you are not putting the fluid directly onto the eye lenses. You should be putting a couple of drops or a quick spray onto your microfiber cloth.Then gently wipe the surface of the lens (after a blow of air to get rid of any loose dust etc). I literally don’t have anything to dry.

Yes definitely not. Perhaps I’m still using too much on the q tip. Tried the microfiber cloth instead but just couldn’t reach the outer edges. Also, almost bought an eyepiece off you, shame I just missed it!

11 hours ago, Robindonne said:

Something like this company is working on.  Basically instead of 2 inch thick glass, they use a fraction of that glass and reinforce it with a second material, probably some fibre like carbon or similar. 

 

it makes the most expensive and heavy telescope part expensive and lightweight.   Lets hope that expensive part will change to affordable
 

http://www.compositemirrors.com/meter-class-telescopes/

Ahh that’s very clever. Much more efficient use of materials.

9 hours ago, Louis D said:

Also known as bar clamps. 🤨  I'm not sure what the preferred name is here.

You know what, so long as it’s not another letter I can forgive that

10 hours ago, pete_l said:

New types of telescope?

One that comes to mind is amateurs starting to image more in the infra red. Primarily to beat the ever increasing scourge of (visible) light pollution.

Infrared, what a good point. I wonder how infrared telescopes compare in terms of atmospheric dispersion etc, are they the same as visible light or are there some fundamental differences?

Oh yes I forgot to mention the use of a bulb blower frequently throughout, quite right! I agree, less cleaning the better. Certainly learned my lesson and eyepieces are staying pocketed from now on.

Hi everyone

I’m very new to telescopes in general but have bought some BST Starguiders. Sadly the two times I’ve gone out they’ve dewed up completely, which I never realised was a problem, but left a fair amount of residue behind. I also accidentally thumb printed one (silly me).

Anyway, I have some baader wonder fluid and started cleaning them. I watched videos but what I noticed was there would always be a residue from the cleaning solution left behind. What fixed it for me was letting dry for 10 seconds or so, then going through meticulously drying it up with cue tips (cotton buds). It felt wrong at first but I kept circling each area until it was clear and that seemed to work a treat, rather than just letting it air dry. I’m sure 99% of you won’t even have this problem, but for whatever reason I’m crap at cleaning things and not leaving streaks (mirrors especially) so if you’re anything like me, try this out.

Also, feel free to share any of your cleaning routines, I’d love to hear them and get more advice! 

15 minutes ago, Robindonne said:

Lets hope composite mirrors get more affordable soon.  That would change the  market a lot.  On the other hand, it would be the only thing that gets more affordable🫤

Couldn't find anything clear in my quick google search, what are composite mirrors?

These are some great answers guys, really interesting stuff. The idea of electronic eyepieces was the kind of thing I was thinking and seems so foreign right now but I imagine would be a huge step up in terms of quality (though potentially a step down in experience). I hadn't heard of a dragonfly array but just looking it up it's a super cool idea. I wonder if someday there will be a multi-scope sort of design that can extract some level of depth and create 3D images (like our two eyes kind of thing). I imagine this would need to have an unbelievably high resolution but would be a cool creation. Adaptive optics is another one I had to look up, but is easy enough to understand. Saw one article saying they're bringing us close to the physical theoretical limits which is exciting. Photography hadn't crossed my mind, but yes of course! In fact, it would make sense that cameras would advance the quickest seeing as they can be developed alongside other industries. 

Thanks for the answers and keep them coming if you have more ideas. Fascinating to think we still have a long way to improve.

Hi all,

Fairly random post just opening up some discussion whilst we have some cloudy skies. I'm very new to the proper side of telescopes and astronomy, having bought my 8" dob as a first real telescope about 3 weeks ago. What I've seemed to notice (although correct me if I'm completely wrong) is that most of the equipment that is quality and recommended has been around for years and years. I suppose when it comes to something as fundamental as gathering and focusing visible light there is only so much you can do. One thing that does come to mind is that crazily overpriced stellina. That live stacking integrated into the telescope is something that seems relatively new and is the kind of thing I'm talking about, besides all the flaws it has. Do you guys think there will be new types of telescope or eyepieces anytime soon that are different from upgrading existing designs, or are we just at the limit of the physics?

1 minute ago, Zermelo said:

and don't forget the F-clamp!

 

There's a lot in that. I think I'm now passing out of that phase, and diminishing returns are setting in - incremental improvements are smaller, and upgrades are getting more expensive!

 

Never seen anything like that! The difference between G and C is understandable, but if Louis tells me our friends across the pond call this anything other than an F-clamp, there's going to be trouble 🤣

Diminishing returns seems like a big factor in astronomy. Compare the best and the worst and the difference is ludicrous, but each step to get there is small and certainly pricey. Worryingly, despite having already spent far more than I thought I would and having everything I think I need, I'm still checking ABS daily for random deals. Almost bought two pairs of crappy old bins on a whim just because they were cheap. Why would I ever need two binoculars!

Absolutely love how this has turned into a conversation about g-clamps. 

Back to the topic, I imagine side by side with top of the line barlows and teleextenders I’d be able to notice a difference, but that’s some of the beauty of being new; every time I get something even slightly better than the bottom it’s a huge upgrade. For example, I had a 50mm Zennox spotting scope as my ‘telescope’ for about 10 years with a broken zoom eyepiece. The new 8” dob is the equivalent of a Rolls Royce to me and aperture fever is a completely foreign concept right now. Same goes with the BSTs, 60 degrees may as well be 360 compared to my ~40 degree Meade MAs!

11 minutes ago, Ian McCallum said:

Does anyone else wonder why there's a G clamp attached to a chimney pot?🤔😂

Oh you bet Ian. Always been my daytime target but never got to the bottom of why someone’s left that there 🤣

1 hour ago, Zermelo said:

I'll be interested to hear how you find it at night time, when the clouds break. I have a few BST Starguiders, but I've never had a BST Barlow with which to try them.

I wish there were more frequent discussions of Barlows (short and long; with varying number of elements) and telecentrics, and how they perform in particular OTAs with specific eyepieces. I appreciate there are a lot of combinations there but, for example, I have a Celestron Omni Barlow and a Baader Q-turret (the latter magnifies approx 2.25 times, a little more than the former, but both are two-element, short models). I have used both of them with eyepieces from several manufacturers, in three types of scope. The most interesting observation that I have so far relates to how my Baader eyepieces behave with the Baader Barlow, compared with the other. An obvious expectation might be that components from a single manufacturer might work better together*, but I have consistently found the Celestron to be the better choice with my BCO 10mm. Specifically, the amount of scattered light seems to be less with the Celestron. By contrast, my 9mm Morpheus seems happier with the Q-turret.

 

* although I do recall arguing this line a long time ago with a hi-fi buff, in the context of audio components. He disagreed 100%, and always bought what he thought were the best separates, from whichever manufacturer happened to make them

Firstly, that’s a very good point. I should probably have waited until a proper test to review as stars will of course be more sensitive than a chimney. 

I also completely agree that people should post their experiences mixing different things. Can speak from experience with guitar that a Fender amp, Fender lead, and Fender guitar isn’t by default going to work better than a Gibson guitar, Fender lead, and Marshall amp. And with astronomy it’s clear that two things with the exact same description can work entirely different, so I’d bet there are some hidden gem combinations just waiting to be discovered. Thanks for your comment.

Hi all

As someone relatively new, I was deciding whether to purchase high power eyepieces or barlow the ones I already owned as budget was a big concern. My eyepieces are BST Starguiders. A BST shorty 2x barlow came up for a good price (£30) and I was very hesitant. Some people said avoid anything but the best barlows, others saying there are very few high power budget eyepieces and to accept the compromise. 

What I found instead is that this barlow works phenomenally with the Starguiders. In my 8” dob (f5.9), the barlowed 25mm compared to the 12mm eyepiece is almost identical (see pictures below). You can just about see the barlow reducing the FOV by maybe 1 degree, but I only noticed this after taking the picture. Visually, I cannot tell the difference. The barlowed 12mm compared to a cheap Meade MA 6mm is night and day, given that I can keep the wide FOV.

If you’re hesitating about this specific barlow, don’t. I can’t vouch whether it’s better than a comparably priced 6mm eyepiece, but you certainly won’t be disappointed by it. 

Update for those of you interested:

Barlow arrived and I’m absolutely stunned by its performance. Compared barlowed 12mm BST to my cheap 6mm Meade MA and that was not even remotely comparable, for obvious reasons. Barlowed 25mm vs normal 12mm and actually felt the barlowed view was brighter and sharper (though the 4x difference in mag could explain this). In conclusion, shouldn’t have hesitated as this thing is clearly built to work great with BST starguiders.