A worthy upgrade?

[PeejaySTB]

Hi Guys,

I have owned a Skywatcher Evostar 120 (F8.3) for some years, I have found it to be a reasonable scope given it's CA problems. As you probably presume, I use it as a visual "all rounder" but I am now looking for something that will show an improvement over it, something a bit sharper, and able to stand a little more magnification. I have a CG5 mount which I added Synscan to.

1. I have the possibility of buying a Skywatcher 100ED DS Pro for around £400, would this be a downgrade due to aperture loss?

2. It has been suggested to me to look at the Skywatcher 150 Pro Mak, is anyone able to comment on this, there are few reviews online.

The ED pro appeals, as it is a frac, and it is portable, coming with an aluminium case, but is it an improvement warranting £400?

The Mak again is portable, and I am told will outperform my scope, but will my mount cope with the weight?

Lunar, Planetary, and the brighter DSOs are my thing. I have in the past owned a couple of Newtonians, and a large Dob, but for me, compact is best, so it will come down to a frac or Mak

Any comments, or further suggestion gratefully received.

Peter.

[belfieldi]

Hi Peter,

I've got a Skywatcher 150 Pro Mak and for lunar and planetary I think it's outstanding, though have only compared it against my 200p dob. It's also very good on the right DSO, but it has a narrow field of view, so it's well worth having a look on a FOV simulator to see if you'd be happy with the 150 Mak on DSO's.

I'm running my Mak on a EQ5 Pro so it should be fine on your CG5.

Ian

[Star Struck]

For my two cents worth, I would go for the 100ED pro. You have mentioned most of the advantages.

They are a reasonable light weight and bcause they contain ED glass, it will give you a well corrected view.

Despite what many folks think, size isn't everything.

[Alan64]

If the splitting of double-stars is to be included within the agenda, the more difficult in particular, then a refractor is in order, along with its other various and sundry advantages.

[John]

The ED100 is a great 4" refractor. It will probably show the moon, planets and double stars a little better than the Evostar 120 does but the latter will beat it on deep sky objects where 20mm of aperture will make a difference.

The 150 mak-cassegrain will be closer to an ED120 in performance so a step up from the Evostar 120 on all targets. They need longer to cool down than refractors though and need dew prevention gear such as a dew shield and / or a heated dew band.

You can get ED120's for around £500 if you are patient 

I ought to add that I've owned all the above at one time or another. Curently my refractors are an ED120 Skywatcher plus an ED102 Vixen.

[PeejaySTB]

Hi guys, thanks for the input, I did take a look at the f.o.v. sim Ian, if I am correct, the mak should be fine for most of the non-diffuse targets. How does it compare in terms of crispness of view with a frac? quality of visual image is the improvement I seek.

I came across a review of the 100ED DS on "Scopeview" and he made this comment which has me a bit flummoxed "unless you plan on using the scope on a GOTO mount, in which case the ED Pro won’t be orthogonal enough to get good pointing accuracy and certainly not enough to align the mount! " He was referring to the optical train being out of alignment with the physical plane of the tube, is this right? if it is I'm staggered. I really like the look of this scope for my budget, but ONLY if I can obtain an improvement with what I currently have. Incidentally, I omitted the 6" Scmitts, should they be in the reckoning?

Many thanks,

Peter​

[PeejaySTB]

Hi John,

If I could pick up an ED120 for £500 I wouldn't hesitate, I didn't realise they would be in that price bracket. Can I assume that your Mak150 was relegated in favour of the 120?

also, your comment that the Mak150 was pretty close to it?

your comment that the aperture loss will be apparent on DSO bothers me, having just experienced my first proper foray into them at Kielder.

[John]

Nothing wrong with the optics of the ED Pro's that I've owned - a couple of the 80mm's, a 100mm and now a 120mm. All really excellent scopes

I've read what that review says and I can only say that I've not experienced that with the scopes from that range that I've owned.

I find a noticable difference between my ED102 and my ED120 refractors on both the moon and planets and deep sky objects. Aperture really does "rule" with regard to the latter. 20mm is quite a bit when we are talking about 4" - 5" class scopes. The 102 is an F/6.5 though so I can get wider views with it as well as going to 200x on the planets so it's very versatile. And rather rare !

The mak-cassegrains I've owned showed great images but cool down is an issue for me as I keep my scopes indoors.

I could confuse things by saying that an 8" F/6 dobsonian will probably out perform all the above for quite a few less £'s but that would not be fair would it !

[catburglar]

I's a tough call between the ED120 and Mak150.

I'd have no problem recommending a SkyMax150. Had one for some time only swapped for a C6 because it was a bit lighter on the nexstar mount.

Not a lot to choose between the Mak and SCT in all honesty, but the mak was probably a tad sharperand better accessories (2 inch visual bak, 50mm finder). Wish I'd kept it really

[PeejaySTB]

Thanks Catburglar, I am surprised to find so few reviews of the 150, but if you think it can stand alongside the ED120 that is very interesting.

[John]

Thanks Catburglar, I am surprised to find so few reviews of the 150...

Here is one of the Orion (USA) badged version of the scope:

http://www.astromart.com/reviews/article.asp?article_id=289

[PeejaySTB]

Wow! thanks for that John, a pretty good write-up, and possibly a decision-maker.

Peter.

[John]

One thing to bear in mind with these mak-cassegrains (it's only a small thing) is that they don't quite deliver the full apertue. The 180mm is a 170mm in terms of actual useable aperture so I guess the 150 would really be something like a 142mm or similar. It's to do with the design of the optical system, the diameter of the primary mirror and the secondary baffle design I believe.

142mm mak-cass is still a nice scope

[PeejaySTB]

Many thanks John, and to all contributors, your help has been much appreciated.

Peter.

[PeejaySTB]

Well, after trawling the net, a good nights sleep and much thought, I have placed an order with Steve a FLO for the 150 Mak..... Can't wait!

[inedible_hulk]

You won't be disappointed [emoji4]

Sent from my iPad using Tapatalk

[John]

Well, after trawling the net, a good nights sleep and much thought, I have placed an order with Steve a FLO for the 150 Mak..... Can't wait!

Good move

[garryblueboy]

A nice choice I have the 180 and it's a fine scope takes a bit of getting used to the narrow Fov but the views are worth it a dew shield is a must they like the dew so much glass exposed .

[PeejaySTB]

Well my 150 Maki arrived today and looks good on my mount, it seems to be solidly built and the finish is excellent. I was terrified of dropping it while securing the dovetail as there is a fair weight in such a stubby design. When focusing on the tip of a distant pylon to set up the finder, the focuser seems to be very smooth and precise, from reports, I was expecting much more shift and frustration. The finder itself looks like an 8 or 9x50 straight through, and seems to have a two screw adjustment arrangement, with a third, spring-loaded holding screw?. I aligned and then removed and refitted the finder a couple of times and found that I had to re-align slightly each time, the finder on my Evostar 120 has a 3 screw setup which seems to lock-up much better, maybe I'm doing something wrong? There was surprisingly little in the way of documentation supplied, the instruction manual being a single A4 sheet folded over, showing me how to fit a red dot finder (not part of the kit). The supplied 2", 28mm LER eyepiece is a nice addition, rather than the 25 and 10mm so often supplied, and the 2" diagonal with reducer for standard eyepieces I have no idea of the quality, perhaps someone can tell me what to expect.

I am really pleased so far, and can't wait to use it, I am now thinking of swapping out my 120, F8.3 Evo for a smaller and faster frac so I can have the best of both worlds.

As garryblueboy has suggested, I expect to experience dew-up, for the time-being I will make do with a piece of camping mat, with a mind that Christmas is on it's way and may bring with it a dew controller and heating tape.

A carry-case for it is a must, any suggestions bettering the £80 or so types I have seen on the main supplier types welcomed.

I intended to post a pic, but frankly haven't worked out how to do that yet, and hopefully I will report on it's "first light"

Thank you all.

Peter.

[Alan64]

Congratulations!

Your new 150mm f/12 Maksutov will be comparable to a 120mm f/15 apochromatic refractor, hence rendering the 120mm f/8 achromat nigh-redundant.  Even though it won't perform quite as a long-focal refractor on the splitting of tighter double-stars, with all its other advantages combined it will make for a fine compromise and substitute.  The Cassegrain family of telescopes were created to simulate long-focal refractors, and within a compact tube roughly a third of the length.

Insofar as a complement to the Mak, think nothing of considering, for instance, an 80mm f/6 fast-achromat, like this one...

For the lower magnifications; wide-field, deep-sky; an RFT it is.  It can even be turned towards the Moon at quite a bit more than half-phase, and with little chromatic aberration.  I've found it to be well-corrected for colour...

The stock Antares 805 comes with a marvelous 2" rack-and-pinion focusser and a 5° field, and over a stock Orion ST80-A.  Also, the build-quality of the Antares is much better than that of the Orion.  I purchased mine from a vendor in Canada, whilst taking advantage of the exchange rate.  I owe the avoidance of the Orion and the acquisition of the Antares instead to a gentleman's post within another astronomy site...

http://www.ontariotelescope.com/Antares-80480-refractor-OTA_p_115.html

[John]

It's nice to see an 80mm short tube achromat with a 2" focuser on it

As far as I know there is only one dealer in the UK that stocks Antares stuff now and they only do the slower "Elite" achromat refractors.

The 80mm F/6 is not listed on the Antares website though  - is it still in production ?

[PeejaySTB]

Hi Alan64, Thanks for your comments, I would be thrilled if it can approach a 120 apo, much wanted, but way out of the budget, fingers crossed. Your Antares is much what I am hoping for in a "trade-off" for my 120 F8, you never know, someone may well be wanting something sharper for Lunar/planetary, again fingers crossed. But in the meantime I will be enjoying my "Frac-like" Mak, I am hoping that like my old Tal reflector it will be a keeper.

Peter.

[Alan64]

It's nice to see an 80mm short tube achromat with a 2" focuser on it

As far as I know there is only one dealer in the UK that stocks Antares stuff now and they only do the slower "Elite" achromat refractors.

The 80mm F/6 is not listed on the Antares website though  - is it still in production ?

The 805 has been available of late, but as to whether or not it's still in production, only time will tell.  I consider mine to be little more than of guidescope-quality, optically and per its star-test, despite my having seen the combined Airy disc of the "C" double-star within Orion's Trapezium under considerable magnification, and rather distinctly.  Also under said magnification, whilst the surrounding nebulosity was colourless it nonetheless exhibited a delightfully misty, even ghostly appearance. The ED "Sentinel" variant, which is listed, is no longer available for purchase.  Its doublet, and perhaps that of the 805 in addition, reportedly having been produced by Long Perng of Taiwan.  The 805's optical tube, dew shield, and all-metal lens cell perhaps, are manufactured there in Canada.  

The 805's GSO focusser is perhaps its finest component, and identical to that of the discontinued yet well-received StellarVue  AT1010 "Nighthawk"...

The drawtube rides on a trio of Teflon strips, but I didn't care for the reflective surface within, so I deadened it with ultra-flat black spray...

...and after I had first removed these two shiny plastic baffles, which, given the considerable length of the drawtube jutting into the optical tube, were perhaps cutting off the light cone...

While I was at it, I cleaned and re-greased the rack and pinion with a Teflon-based lubricant; Superlube, and food-safe, incredibly.  There are to be other and few improvements to make, but not too terribly difficult, and to ensure the refractor performs at its very best. 

Why, it even came equipped with its very own vampire-star and victim...

The doublet's coating are quite nice.

[Alan64]

Hi Alan64, Thanks for your comments, I would be thrilled if it can approach a 120 apo, much wanted, but way out of the budget, fingers crossed. Your Antares is much what I am hoping for in a "trade-off" for my 120 F8, you never know, someone may well be wanting something sharper for Lunar/planetary, again fingers crossed. But in the meantime I will be enjoying my "Frac-like" Mak, I am hoping that like my old Tal reflector it will be a keeper.

Peter.

I'd love to have one of those 6" Maksutovs myself, and well over and above a less-than-comparable 6" Schmidt; again my congratulations, and thank you!

[John]

...and after I had first removed these two shiny plastic baffles, which, given the considerable length of the drawtube jutting into the optical tube, were perhaps cutting off the light cone...

Do you know, that did cross my mind when I saw the photos of the scope you have posted on the CN forum. With a 2" diagonal, the top end of the drawtube would be well up inside the scope. You would hope that the designers would ensure that it did not cut into the light cone but it has been known to be done