What's the limitating factor as I go up in magnification?

[chiefgibbon]

Hi Umadog

I don't want to derail the thread, but watch out for the Hyperions: they only work well in slow scopes.

Which kind of illustrates why I'm still not buying any EP's right now!  Everything I've read about these previously suggests they're brilliant; there's just too much I don't know to make a good choice. 

OK so I had a short window earlier where I was able to play with the scope in daylight (cloudy skies so no point once it's dark).  I've made some improvements.

Firstly collimation, which was OK, but what I hadn't previously noticed is that there's a fair amount of slop in the focuser so that you can 'waggle' the collimator - and this moves the red dot around.  I tried putting some PTFE tape on the focuser threads to see if I could eliminate the wobble - but even a thin coating prevented it from being screwed in.  I guess it's a bad idea to have grease anywhere near optics so I gave that option a miss.  So I figured do the collimation with the scope at 60 degrees elevation, which is a typical viewing angle, that way it would flop to where it will normally sit while viewing.  I did this then waggled it to see how much the dot moves - which is quite a bit actually - and tweaked collimation a little more so the 'average' position of the dot was a bit closer to the centre.  Basically I found a compromise position.

Secondly I spent some time looking through the 10mm + barlow combination to see what effect my eye position has.  Basically if I jam my eye closer to the EP the contrast improves and things become clearer.  I don't know exactly what's going on here but getting my eye closer seems to reduce ghost images in the way. I also played around with the slop in the focuser, basically the focuser moves a bit when you let go of it after achieving focus.  So I found that by focusing by pushing the EP locking screws, rather than holding the focuser, that's reduced and it's possible to get a better 'hands off' focus.

Finally I wrapped some paper round the open parts of the tube to make a simple shroud - I've ordered some neoprene to make a proper one + dew shield.

I was viewing a lamppost around 70m away - far enough to get in focus with the highest mag.  With 25mm I could just make out that there's a spider web on it; 10mm I could see more of it; and with 10mm + barlow I could see some trapped flies!  The view at the highest mag definitely has less contrast and looks less pleasing, and is still not as clear as I'd hope; but objectively it's showing me more detail.  Which is better because previously I could see more with 10mm and no barlow!

[Schorhr]

Sounds good :-)

On the heritage, I only use the cheshire-sighttube, as it's easier with the not-so-perfect focuser, precice, and the tube is short enough to look and reach the adjusting screws.

Good luck!

[chiefgibbon]

Hi Schorhr,

Often, buying more equipment is what happens when the weather is bad long enough or if we are looking for an excuse for not going out more frequently It's not like there is not enough to see out there...

Right, and don't get me wrong I'm as prone to getting obsessive about 'gear' as anyone; I'm just doing a good job of resisting right now!  (Having no spare cash helps!)  I get so much pleasure from scanning the sky with my binocs, and am keeping in mind that the scope will show me so much more even with just the 25mm EP, the views from which appear crystal clear to my eyes right now (I've not been spoiled by 16" mirrors and expensive EPs yet!). 

For example I never realised how exquisite the moon really is; for example the big craters near the south pole (I'll figure out their names one day) are breathtaking: the sort of view you only really expect to see in a movie.

Thanks for telling me a few more good targets to try to find!

I am really impressed with the little scope all considered; however I reckon a replacement mount could be made to do the same job at half the weight with some plywood, well placed cutouts and bracing.  I might give this a go when I have a bit of spare time!  The OT is really light and could happily be carried for miles; a lighter and more easily luggable mount would be superb!

[LukeSkywatcher]

Bit late to the party here but i agree with anyone who said that the limiting factor to the Heritage,or any scope is the "seeing and/or transparency."

If you live in this part of the world (Uk and Ireland) and the telescope sales pitch you buy says you can get 500x..........................you can automatically cut that in half.

[AlexB67]

I am really impressed with the little scope all considered; however I reckon a replacement mount could be made to do the same job at half the weight with some plywood, well placed cutouts and bracing.  I might give this a go when I have a bit of spare time!  The OT is really light and could happily be carried for miles; a lighter and more easily luggable mount would be superb!

The Heritage is a cracking package IMO, offering nice wide angle views that is hard to beat at that price in a package that small and light, while still having a fair amount of humpff for deeper sky stuff too.  When I got it out not so long ago  compared to the bigger scope for a quick session that turned an all nighter, that point was hammered home how easy it is to work with.

Without breaking the bank you can improve those views quite a bit with lets say 3 or 4 extra eyepieces. In time you'll then decide if you love it enough and also decide how much it is worth  getting additional eyepieces and other accessories for this scope, or get a bigger or different scope and so on. Some observers take different routes depending what they want from the hobby. All I would say is that the heritage is a keeper in my collection 

[Schorhr]

Hello Martin,

if you do build a lighter mount, do share the plans :-)

But the current mount is a good compromise and from building light simple mounts I encountered one issue: Stability. The heavier mount does dampen vibrations a bit more I suppose.

I often carry the OTA in a backpack and the rockerbox-mount on it's handle (that I have covered with pipe isulation foam and zip-ties so it's not hurting the hand as bad, especially when carying it with the scope to the next field outside of town).

Oh, and about the moon; http://www.skyandtelescope.com/observing/objects/moon/3308811.html

Paul is right, the heritage pretty much covers what's possible with "standard seeing" :-) Though of course a larger mirror means a larger exit pupil even at lower magnification, and more resolution.

But other then the Litescope and something like a Sumerian in 8"-10" is not as portable. And the Heritage has a better price tag and easier handling ;-)

[chiefgibbon]

Hello Martin,

if you do build a lighter mount, do share the plans :-)

Certainly will, not sure when I'll get round to it though, my ToDo list is quite long at the moment.

I do agree it's a brilliant little scope, I chose it not mainly because it's cheap but because it's small and portable.  I expect I will get a bigger scope one day but I will certainly keep it (with a few mods!).  Portability is always going to be a big plus for me because although I can do some observing from home it's not a great site, what with LP and obstructions all around (like my house for example!).

And thanks for the moon link Marcus!

Beautiful clear night last night down here, clearest I've seen for a long time - and I was out doing other (admittedly fun...) things and couldn't get the scope out, grrrrr.  

And tonight?

[Schorhr]

Yeah, it's been the best downgrade I made, and now using it for video astronomy - or trying that is

Good luck!

[lensman57]

Hello all,

So I've been playing with my new SW Heritage 130p for a few weeks now (on the rare cloud-free occasions), and the eyepieces and free Barlow that came with it, and getting used to it all!  I'm really pleased with the scope (although it's not quite so universally 'better than binocs' as I'd probably expected - I'm getting used to that too). 

I'm trying to understand what's limiting my views as I use the higher magnifications.  I have a 25mm, 10mm and 2x barlow.  I find that I can't seem to get sharp focus with the 10mm + barlow.  Both EPs on their own produce a fairly crisp image, and the 25mm with barlow seems fine - in terms of clarity it's hard to decide between the 10mm vs 25mm + barlow.  However when I go to 10mm + barlow, even on a bright target like the moon (or during the day looking at a distant building), it's as though I can't get proper focus.  Everything's fuzzy.

I'm not necessarily looking to buy / upgrade anything, really I'm just trying to understand what's the limiting factor.  The highest magnification gives me 130 x I think, which should be within the limitations of the scope size and optics?  Assuming so, from googling around it seems like it could be:

 - seeing conditions

 - eyepiece or barlow optics

 - focuser

 - lack of skill

 - I guess it could be my eyeballs!

And I don't have the experience to decide which!

Can someone offer me any clues?!

regards

Very simple. The same amount of light that comes in from the object has to be spread over a much larger area because of using a higher powered eyepiece, in a word the light gets diluted,  hence your dimmer view. Sometimes with small aperture scopes such as yours you are better off using a low to medium powered EP for a higher contrast and brightness view.

A.G