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I love my starblast 4.5


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Oh it was beautiful tonight! However, the moon was out so not very much visible. I did some surface observing but that was pretty much it. Still very cool for me considering my first time i actually had the patience to stay on something and look more closely at the detail but need to purchase a filter because boy was it too bright! Hopefully not to dangerous? Also looking forward too a lunar map to start looking for things on the surface. Its all so facinating that its been hard for me to slow down and truly appreciate what im looking at! 

Good night all,

 

Chad 

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The Moon is endlessly fascinating as the terminator moves across - really highlights crags and craters. One of my favourite sights are the lava ' waves' that cross Sinus Iridum.

Then there's always the Lunar 100 list to follow, should you fancy...

The brightness of the Moon is not harmful so don't worry. Whereas the Sun - full aperture solar filter ONLY!

Some use a Moon filter ( a grey neutral density filter ); generally I don't find one necessary but use a double polariser if I feel like experimenting.

Lunar atlases are wonderful - I recommend the Cambridge and the Kaguya among others ( there's a fair few to choose from!) There's also a good, nay great online HD map. Loads of links to this on SGL, but sorry I can't link it right now. The S&T foldouts are really good too, and laminated so useful outside.

Some don't particularly love our Lunar sister as she washes out fuzzies and nebulas but she is such a special and rewarding companion ( you're looking at the surface of another world!!!) that I never tire of her...

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Ill tell you one thing! Orions nebula was still absolutely glowing for me. I did look at that first but was surprised at how much detail i could see with it being so close to the moon. Im just excited im having as much fun as I am. I just cant thank you guys enough for the info.

Chad

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That's the link! Thanks Imp!

Chad, Mars, Neptune and Venus were ( are) almost in a line here in the wsw....visible from PA? 

Neptune is my last planet to find, but having only bins tonight, no chance! Good thing about stargazing - nuthin's going anywhere soon so there's plenty of time left.  Assuming I'm going nowhere soon, lol....

 

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Yes i agree! And mars and venus definitely are but havent looked for neptune either. Ive been so amazed at the moon last night and orions nebula that i havent searched to far yet. Like you said plenty of time... 

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Heya Ghost!

Taking good care of our telescopes, regardless of inconsequential matters like age & cost, are pre-wired into us astro-peoples's heads. That's why there are telescopes that  built in the 19th century - that still serve active service by professional observatories & astronomers. These wonderous instruments are linked to forever, which fits them perfectly if you add the subject matter they study. So Chad - your love is well placed!

So you've gone over to the 'dark-side,' eh Ghost, and now wield an ST80 in London? Welcome to the fold! These little darlings are truly wonderful, if you understand what they excel at and use accordingly! It's become my designated scope for many things & locations - as well as my preferred 'grab & go' instrument.

 

st80 club.jpg

 

Off to the cloud-bank that has been my sky of late -

Dave - The Frozen-One

 

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The apparent views of the eyepieces (how big the image circle is when you look into the eyepiece) are about the same. The lower focal lengths will give a more magnified but darker image. The longer focal lengths will show a wider and brighter view. 

However, if those 66° eyepieces are the black ones with the gold stripe I suggest you avoid them. I used the 15mm once and it was the worst eyepiece I've ever looked through. 

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Thanks for the reply! The 15 and 6 came with the scope and so far have been very good. Im just doing some research to see where i want to go next and have heard alot about low mag and wide field of view for my scope so just trying to pick brains a little...??

 

Chad 

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Well given that you already have the 6 and 15mm you can use those to figure out what it is that you are missing. For example your 15mm gives you 30x and a real field of view (RFoV) of 2.2°. The 24mm 68° eyepiece will give you 19x and 3.6°, which is the widest view that you can get out of the 1.25" focuser. If you look at your targets and find that you can't fit everything into the view given by your 15mm then by all means go for the 24mm, however, if you don't come across that problem then perhaps the 24mm is more of a luxury than a necessity. You would also find star hopping with the 24mm easier due to the increase in field size so that would be another consideration. A final consideration is the exit pupil that the eyepiece would give with your scope. A dark adapted eye can expand to about 7mm at a dark site. A 24mm eyepiece will give a 6mm exit pupil so you probably don't want a lower power that that and in fact even that may be too big of an exit pupil at a light polluted site. The other option for a maximum RFoV is a 32mm Plossl but that would give an exit pupil of 8mm so I would definitely avoid that. 

It is often recommended to use an eyepiece with an exit pupil of 2mm. In your scope this would be achieved with an eyepiece of approximately 8mm. 

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Aloha Frozen Dave!

Yep, I couldn't resist the ST80 when I was looking for a wide field grab n go. And being a bit of an Orion fan,  their lil cutie just had to be mine :) Took about 30 seconds on first use for me to be besotted. 

Of course ( the Stan Lee in me is tempted to say 'natch'!), since then it's been all work or the grey stuff - the few clear nights, natch, were right before early starts at work, so I've been a bit star-starved lately :(

But hey-ho, gives me more time to peruse the forum.....er, that's not necessarily good is it? ;)

 

PS love the T! Can I get one in midnight blue?

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Okay, Chad - time for a relatively simple math-lesson...

I am assuming this is the telescope you have:

 

Orion Starblast 4.5.png

 ( If not, plug in the correct numbers. This formula is the same for any telescope. )

To find the magnification of an eyepiece in a telescope, you need the Focal-Length of the telescope. The Orion Starblast 4.5 has a Focal-Length (we abbreviate this as: F.L.) has a F.L. of 450mm. And we need the F.L. of the eyepiece in question, Let's start with the 6mm. And we do this:

450mm / 6 = 75X

So 6mm divided by 450mm F.L. gives you 75X power eyepiece.

Ghost's suggestion of a TeleVue® 32mm Plossl EP would yield about 14X. This would be a nice low-power EP (EP = eyepiece, obviously) for extended targets, like the Orion Nebula - M42 - and M31 - the Andomeda Galaxy. Many people, when they just start out with telescopes, presume a good telescope can really "pour on the power" at high magnification. But this is an erronious assumption. What a telescopes' best property is their light-gathering ability. And this is determined by the aperture of the main mirror (reflectors) or lens (refractors) or combination of both (Schmidt-Cassegrain - SCT's or Maksutov-Cassegrains - Maks). The larger the diameter (aperture) - the dimmer the objects, measured in 'magnitude,' they can 'see' and show you. Magnification is of secondary importance to most of us.

I'll let someone else help to explain the F.O.V. of EP's and what this truly means at your eyepiece.

Back later -

Lazy Dave :p

 

PS - I see that Orion has two "Starblast 4.5" Telescopes - both have a F.L. of 450mm though. So this works for both!

 

Orion Starblast 4.5 EQ.png

 

 

 

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Thank you dave! I understand that part just debating if my 15mm is wide enough for now and get a Barlow for other things or if i want the wider view? Haha ill check back and let you know what i decide... I didnt understand why the degrees were the same... 

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5 hours ago, Dave In Vermont said:

I see that Orion has two "Starblast 4.5" Telescopes - both have a F.L. of 450mm though. So this works for both!

Oops, I thought that it was just the Orion branded version of the Skywatcher 1145p with a focal length of 500mm. I'll have to edit the numbers in my previous post. 

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19 minutes ago, Ricochet said:

Oops, I thought that it was just the Orion branded version of the Skywatcher 1145p with a focal length of 500mm. I'll have to edit the numbers in my previous post. 

Sneaky devils these telescope companies, eh? :p  If I hadn't looked and saw the OP was from within the US, I'd have been utterly at a loss, too!

Yipes -

Dave

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7 minutes ago, Dave In Vermont said:

Sneaky devils these telescope companies, eh? :p  If I hadn't looked and saw the OP was from within the US, I'd have been utterly at a loss, too!

Yipes -

Dave

Indeed, especially as we know both models could be coming out of the same factory. 

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