Delayed Gratification

[chiaroscuro (Luke)]

Hi all,

I've been lurking for a while, soaking up the vast amounts of information provided by you guys and gals, and naked star gazing for some time, as I'm about to embark upon a hobby that I've been wanting to pursue for a while, but delayed until other financial priorities were sorted - thats taken about 19 years!
Anyway, I'm in the fortunate position of having nice sum to spend on equipment, and I'm torn between a 10-12" SCT and a 127mm Skywatcher Black Diamond APO on a Goto EM. Now, I am a beginner, but a very patient one that wants to take time to learn the sky and learn how to use a scope properly as a visual observer, but potential AP later - more importantly, I don't want to buy another telescope in the future because my initial choice was wrong. On the mobility side, I would be observing in the back yard, and sometimes travelling by car with the scope, and I'm hoping to use the kit every 2nd-3rd weekend (conditions permitting) for 2-4 hours per weekend night.
My understanding is that the refractor will cool down quicker, provide better contrast but lower resolution than the SCT, and be a bit more transportable.
So my question is, which would better serve me in the longer term?

Thanks

Luke

PS: If I wear clothes when I'm star-gazing without a scope, is that naked star-gazing? Just clarifying the lingo.

[Camelopardalis (Dunk)]

Welcome Luke!

The 2 scopes you mention are quite different in what they'll show you and how it will be presented. What sort of objects are you interested in looking at? And for AP?

The refractor should no doubt give you fine views, and a relatively wide field of view compared to a large SCT, but a larger aperture scope will have much greater light grasp. You'd probably need to be using a similar mount for both scopes, so the portability thing will likely be marginal...one is a long thin tube while the other is short and dumpy

Have you ruled out a reflector/Dobsonian? You could probably buy quite a substantial setup if your budget stretches up to a large SCT and mount.

[chiaroscuro (Luke)]

Hi Camelo,
I suppose I want to see everything! Planetary detail, other galaxies, nebulae. Is it practical to use s SCT for planetary detail? Would the refractor be able to see as much detail (given the appropriate eyepiece)? I suppose thats my dilemma - will the refractor have the flexibility to see detail to the same degree as the SCT, and is the SCT limited by loss of contrast? Which would be the more versatile of the two?

Thanks
Luke

[Camelopardalis (Dunk)]

If you want to see everything... then you'll need a bigger scope

The SW 120 apo should more or less match a small SCT (6") for detail, but not the larger ones. Light grasp is important for planetary too.

For nebulae, clusters, galaxies... it's aperture that counts. A larger reflector (SCT, newt, Dob...) will win practically every time unless the subject is particularly large such that it won't fit into the field of view of the larger scopes.

The contrast situation of SCTs is often overhyped as all the surfaces these days are coated for good light transmission and the secondary obstruction only reduces the contrast by the proportional amount of aperture. If you could compare a 10" SCT to a 10" refractor, you might see some difference, on a good night what you see with a large scope, at least at higher magnifications is affected by how good the atmospheric conditions are.

If you want better contrast, prepare to empty your pockets for either a large apo or large Mak and a more expensive mount

Many people here have more than one scope because any single design doesn't excel at everything. It's just a question of picking the scope that matches your priorities the best. You might find that a solution that includes a smaller portable grab-and-go scope and a larger aperture beast works well.

[chiaroscuro (Luke)]

After lots of agonising, I decided to go with the refractor, and picked it up last Friday. Its a bit daunting opening up those boxes and realising there is a whole lot to learn just to set it up, before even looking through it, but I did that on Friday night, just in time to see Saturn, which was mind-blowing.

I spent the next day getting to know the HEQ5 Pro mount, but despite all the reading I'd done about polar alignment, I could not get the scope to align properly. Doing a 3 star alignment, each time it slews to the nominated star, its way off target, even through the finderscope, let alone the 120mm refractor. All the date, time, location details are correct, and I followed step-by step, the superb notes by Trevor Hand (Thanks heaps) on IIS, on the Basic set-up. I used a compass to point the mount at 168 degrees (12 degrees East of magnetic South should be True South?). The latitude is set to 34 degrees on the mount, and I set the zero point for the central meridian of the time zone at zero (150 degrees longitude). (Not sure what to do with the date scale either - no instructions in this)

There's a polar alignment scope in the mount, but I can't identify Octantis through it or the OTA. I'm sure the problem lies with my poor knowledge of the sky - its early days for me. My question is, if I do eventually identify Octantis, should I physical move the tripod with the mount in the "home" position, to align it as closely as possible with the SCP, or can I just adjust the RA and Dec to line it up?

Anyway, I ended up spending each night over the weekend browsing the night sky. Seeing Saturn and Venus was great, but I got a huge surprise when I pointed the scope at the small magellanic cloud, and focussed in on a fuzzy spot -all of a sudden there is this beautiful globular cluster with thousands of pinpoints staring me in the face. I was just blown away. And then I went to the large Magellanic cloud, and I'm sure I saw a nebula there. (I'm sure you're getting the picture of my knowledge of the night sky)
Sunday night, the seeing was really good, so I just scanned the night sky again, after another failed attempt at polar alignment, and spent the time trying to learn the night sky.

So if anyone has some advice to help a confused beginner do a Polar alignment with an HEQ5 Pro mount, you'll probably stop a grown man from curling up in the foetal position and crying, any moment now.

[Steffen]

Hi Luke,
accurate polar alignment isn't necessary for decent GOTO accuracy. If your polar alignment is within a few degrees you should be ok. Away from home I often miss South by as much as 10 degrees during initial setup, that doesn't keep my 2-star alignment from working (and displaying the correct polar alignment error).

You didn't mention the SynScan version of your hand controller, but for all versions above 3.0 a lot of problems magically disappeared for me when I used 2-star instead of 3-star alignments. Try that first and see how you go.

Also (you probably know that already), the date needs to be entered in the format month-day-year, American style. This is an easy one to get wrong for unwary SynScan newbies.

Cheers
Steffen.

[chiaroscuro (Luke)]

Hi Steffen,

To be honest, I cant remember what version of Synscan it was, but I assumed it was the latest given that I bought the mount last week. I'll check that. Is it pretty straight forward to update the firmware?

I definitely put the date in US style, so I'll see how I go with software update.
I suppose I still want to learn to do a polar alignment properly. When I think of Sir Isaac and Leaonardo Da Vinci and how much they achieved with their basic equipment, its almost like paying homage to them the learn the process!

Cheers,
Luke

PS. I realise now I was looking at 47 Tucanae in the SMC, and maybe the Tarantula Nebula in the LMC.

[Steffen]

Yes, the firmware upgrade is rather straight-forward, the current version is 3.35. The tool for this is downloadable from the SkyWatcher site. If your PC doesn't have a serial port you'll need a USB-Serial adapter.

Do the 2-star alignment and you'll be much happier. Once the GOTO pointing is sorted out you can use the built-in polar alignment routine and within minutes get good alignment for hours of tracking.

Cheers
Steffen.

[chiaroscuro (Luke)]

Only problem Steffen is that I have a Mac, and from my brief foray into the upgrade process, it doesn't seem Mac-compatible. I just looked on another forum, where someone had to partition their Mac to run windows, just to update the synscan firmware! Hope I don't have to do that.

I'll keep investigating.

Cheers,
Luke

PS. Just managed to translate the Latin under your name - I like it.

[Steffen]

I'm using a Mac, as well. I run the firmware update tool in a Parallels virtual machine (VMware Fusion works too, VirtualBox may as well). No need to repartition.

Cheers
Steffen.

[Camelopardalis (Dunk)]

Congrats on your new scope Luke

[chiaroscuro (Luke)]

Thanks Dunk. It's pretty exciting to literally have the whole universe waiting to be explored. All I need is a Synscan upgrade to launch into that with gusto.
Cheers
Luke

[Camelopardalis (Dunk)]

I've heard positive things about the Synscan updates, although I've yet to try it myself...want to soon. My Celestron mount allows you to add calibration stars which really sweetens up the gotos.