Skymax 127 Mak or SW 100ED?

[RikM]

I have a 127Mak and a 70mm refractor and the star shapes and planetary views are better in the little refractor. Okay, I'm comparing possibly a poor example of a Skymax with a very nice Televue Pronto, but for me the star shapes and contrast swing it heavily in favour of replacing the Mak with 100ED or maybe even a 120.

[DevonSkies]

Thanks for all the comments in this thread. I think from what I've heard I can conclude that, although the Mak is a good little scope, the 100ED is worth the extra for the best planetary views. I think, deep down, I knew this all along.

If I'm lucky I might find a used 100ED near me; otherwise I'll scrape together the cash for a new one. I don't want to plump for the mak and then wish I'd got the ED all along.

Edited February 20, 2016 by DevonSkies

[JG777]

23 minutes ago, DevonSkies said:

Plenty of food for thought.  I've also been considering the Altair 102mm f/11 achromat as an other option. It's a lot cheaper than the 100ED, but obviously will exhibit a certain amount of CA on bright targets. Whether the CA would be bad enough to justify spending the extra on ED glass is not clear to me. The longer tube of the f11 scope also makes mounting more of a problem. 

It will be clearer literally if you have a apochromatic refractor. I also had a ST120  at the same time as the others and when it came to taking one of them out the 100 ED pro won out every time as the CA in the other scope was a bit too much for me, mind you the ST120 excelled at wide field thanks to the shorter F number. It's one of these things that when you look through an APO refractor you will always want to look through one and anything less gets left behind in the storage cupboard. Thinking more about the views between the 100 ED and the Mak the refractor gave much better contrast and punchier colours than the Mak on planets, but the Mak was a moon killer for detail. Personally I think the 100 is worth the extra as you only buy this scope once and its a keeper. Then at a later date add a Moonlite focusser and it becomes seriously impressive. For grab n go its hard to beat a refractor especially when you want fast set up, clear skies are few and far between and they do not stay clear for long.

 

[happy-kat]

In feeling a drift from the brief by looking at f11 refractors

On size, perhaps the cool down and view out strip the size/length growth.

Edited February 20, 2016 by happy-kat

[BGazing]

i cannot compare, but my 127 on goto works well, is fairly portable and the setup time is good.
if you do your alignment as accurately as possible (esp by defocusing stars and using zoom to further center dead on), goto is remarkably accurate and the tracking is good. remember to round gps coordinates towards the closer figure.

battery pack will last a while, but now i got myself a big lipo battery (portability is premium and these give a lot of power in a very portable small pack), heated dew shield, etc.

btw, when making up my mind, i was also torn between 100 ed and 127mak...and went for the later for portability.

Edited February 20, 2016 by BGazing

[Alan64]

I read somewhere, recently, someone saying not to let Sky-Watcher know just how wonderful the 100ED really is.

[John]

11 minutes ago, Alan64 said:

I read somewhere, recently, someone saying not to let Sky-Watcher know just how wonderful the 100ED really is.

I've owned a couple of the Synta ED80's, one of the early ED100's and currently an ED120 and they have optically all been really good scopes. The glass used in the objective lenses is Japanese apparently and it's rumoured that Vixen were involved in the optical design. There may be something in that because a little while back Vixen included 80mm and 100mm ED doublets in their range that were basically re-branded versions of the Skywatcher / Synta ED80 and ED100.

 

 

 

 

Edited February 20, 2016 by John

[Alan64]

The 100ED would indeed be worth the striving towards, as the Japanese Ohara ED-glass element is FPL-53, and the best optical-grade glass in the world at present, second only to fluorite, with the other element being of German Schott crown.

[okm]

On 19/02/2016 at 04:47, dweller25 said:

Because the ED100 was easier to cool and could keep up with dropping temperatures through the night it gave sharper and more stable images quicker than the 127 Mak.

The clear aperture of the 127 Mak is actually 120mm, which means the 46mm secondary gives a 38% obstruction - this reduces planetary contrast to about the same as a 2.9" refractor, so a 100ED will have more contrast - vital on the planets IMO.

I have also compared the ED100 to my Takahashi TSA102. The ED100 gave embarrassingly close planetary views to the TSA102 !!!!

In my opinion the ED100 is superb value for money.

This is an old topic, but I did want to correct this in case others are reading as well.  46mm obstruction for the Mak is not 38% - you need to look at the obstructed area, not the diameter.  The obstruction is about 1662 mm^2, resulting in the unobstructed area being about 9645 mm^2.  That's equivalent to about a 111 mm aperture.  So the Mak should still have a more light coming through the lens.  It's still more complicated than that because there is some loss from the primary and secondary mirrors.

[RT65CB-SWL]

Hi @okm and welcome to SGL. 

I think your answer sums it up nicely. I admit it, I have a Meade ETX105 [re-mod] and a Celestron C6/SCT , (images below), and forget to mention about the central obstruction when advising on a 'What telescope...?' thread. I also have a TeleVue Ranger, (last image), shown with a Lunt solar wedge attached.

Edited September 4, 2019 by Philip R

[dweller25]

On 03/09/2019 at 05:59, okm said:

This is an old topic, but I did want to correct this in case others are reading as well.  46mm obstruction for the Mak is not 38% - you need to look at the obstructed area, not the diameter.  The obstruction is about 1662 mm^2, resulting in the unobstructed area being about 9645 mm^2.  That's equivalent to about a 111 mm aperture.  So the Mak should still have a more light coming through the lens.  It's still more complicated than that because there is some loss from the primary and secondary mirrors.

The data I gave is correct - you are confusing contrast levels with light throughput which are two different factors.

So we are both right 🙂

Edited September 6, 2019 by dweller25

[Limerick John]

I have had the Skywatcher 127 Mak for about 18 months now and have just bought a 100mm F7 ED refractor.

For the money, the Mak is very hard to beat. Very sharp optics, great lunar and planetary details, double stars and the brighter clusters and nebulae all shine in this instrument. It handles high magnification well. On a low cost AZ4 mount it can be carried outside with one hand and ready to use in less than a minute. You can attach a camera directly to the scope for great lunar shots or for daytime use. It is my most used scope. I have replaced the supplied diagonal and eyepieces

The refractor is great for wide field views. It gives good planetary detail but needs a barlow to get close to the Mak due to the lower F ratio. A bit wobbly on the AZ4 at high power and catches the wind more. They both complement each other well and are grab and go.

If my interests were just the planets and moon and the brighter DSOs (say living in the city) I would get the Mak, upgrade the diagonal and a get few decent plossl eyepieces. Same applies if I was on a tight budget. If money is no object-get both.

[Limerick John]

On 19/02/2016 at 12:01, DevonSkies said:

Thanks, that's really useful information.

It's a tough choice. I can afford the Mak 127 right now, but I'd have to save a bit longer to buy the 100ED. I've also got a feeling I would eventually need to upgrade my mount for the 100ED, as the Porta II suffers from the wobbles at high magnifications, which will only get worse with a longer tube. On the other hand, cool-down is a concern with the Mak, as I tend to have limited opportunities to observe, except on those rare clear, still nights.

If you already have a Vixen Porta II mount then you are sorted. The shorter Mak is much more steady on a mount like that. The 127 OTA is only £279. I wouldn't bother with a goto mount in a telescope that size unless you really want one. Just another thing to go wrong eventually. 

I upgraded to an Orion dielectric diagonal (its a bit longer that some of them and is more comfortable to use). I already had a set of Meade Super Plossls. A 32mm eyepiece works well as my lowest power eyepiece and makes finding objects easy with just under a 1 degree field of view, especially with a  Telrad mounted on top of the instrument. I have never had an issue with excessive cool down times.

I have not used the SW100 ED but I believe they are very good value.  At F9 it could be a bit wobbly on a Porta II. You won't go wrong with either telescope.

Edited September 8, 2019 by Limerick John

[davekelley]

I have owned both these scopes and I sold the 100ed.  I won't be selling the mak.  I'm no expert and I'm only an occasional, casual observer, and I liked the views in the ed but for some reason I prefer the views in the mak, it seems to pull in more light somehow, and get more pinpoint stars, it's a lot more manageable, takes up no space and I like the simplicity of alt-az/goto!  For someone like me, with poor skies, and I've owned dobs from 150-300mm as well,  the mak is the perfect compromise.  It would be very easy to take it out somewhere really dark as well it packs away so small.