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Skymax 127 Mak - Star Diagonal upgrade?


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Can the performance of the Skymax 127 Mak be improved significantly by upgrading the star diagonal that comes with it?

Has anyone upgraded the star diagonal on theirs. If so what with and did it improve the clarity or brightness of your views and above all was it worth it?

Clear skies to all,

Mark

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Hi Mark,

This old thread of mine - Choosing a Diagonal - covers some of your points.

If you do upgrade, don't rule out a 2" diagonal for fear of being unable to use 2" EPs.

I use 2" wide-field EPs in my 180 Pro (big bro' of your Skymax 127) without any vignetting.

And this despite the fact that the baffle tube, where it comes through the visual back, has less than an inch of internal diameter.

If you do decide on a 2" diagonal, you will need to get a Mak-SCT adaptor and an SCT diagonal to do the job.

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Thanks David, I appreciate your insight. I hadn't thought about the 2" possibilities. I have a budget though, of about £55-£70 so that will probably limit me to the 1.25" if I decide to do this.

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Hi,

The William Optics 1.25" Carbon Fibre Dielectric Diagonal from FLO is in your price range. I use it on my 6se and it is a very good diagonal.

I don't think it will make a huge difference. The money would be better spent elsewhere if you are on a limited budget.

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It'll not make a perceptible difference in my experience. I have flipped between really top class stuff like TeleVue and cheap diagonals and there is precious ittle to choose in all honesty. You'd be far better off getting yourself a 2 inch and a widefield EP to open up the view so as to enjoy the larger clusters.

Olly

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Thanks for your replies guys.

Would a 2" diagonal and a wide field EP give me a much wider view from this scope. I was given to understand that this wasn't possible because of the physical restrictions of the scope being of long focal length an all. (Skymax 127)

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I was given to understand...
It's contentious? I think, no matter how far we, "the advocacy" try, there will always be "nay-sayers" on the topic. [teasing]. But it is my (and precedent) observation, if you put a 2" diagonal on the back end of a MAK127, you can use many wide angle 2" eyepieces. My feeling is that it is not the "exit orifice" that vignettes, although this does echo the secondary mirror baffle and remote end of the mirror transport tube? Yet "somehow"... sufficient light creeps around the edges of these limitations to illuminate (at visual levels) a circle equivalent to the field stop of many a wide angle 2" eyepiece. ;)

For users of the Skywatcher Synscan (and Syntrack?) mounts, a more practical limit is [iMO] the (total) WEIGHT. Slinging all this stuff on the back end, may be corrected balance-wise, but things start to creak and groan a fair bit? More obviously, the GoTo (at the limit for a MAK127), starts to "miss" objects (more)? :)

But, if you have a suitable mount, a 2" diagonal is a good thing. You cannot make a wide-field 'scope of the MAK127, but you can get useful extra field e.g. for "framing" open clusters. Even a modest 30-40% (say) increase in TFoV is useful. Heck 10% on the Ethos AFoV launched a whole advertising campaign? :(

As mentioned above, you can also play the same trick with the MAK150 (and seemingly the MAK180) - I took a chance on the "150" being simply a "big 127"... I was not disappointed. I am happily using e.g a 2", 31mm, 72 deg Hyperion Aspheric on both the 127 and 150. I sense a tad more field is possible... :(

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There are two camps of opinion about the use of 2" EPs in the mainstream, comercial Maks:

Those that say nay because the narrowness of the central light baffle will cause vignetting, especially in wide field EPs. (Chris, I'm pretty sure that the mirror transport tube is the choke point in the optical path. Mind you, I suppose that it could be the diameter of the secondary spot mirror. ;))

Then the yea sayers insist on problem free use of 2" EPs with no, or very little, dimming around the edges of the view - irrespective of eyepiece type, or the use of focal reducers. Mentioned here, and elsewhere in the forum.

I've been using my 2" wide-fields in the Skymax 180 Pro. Both the Series 4000 QX (30mm, 70º aFOV) and the Revelation SV (40mm, 65º aFOV) are tack sharp, as you would expect with the long focal length, and show no vignetting to my newbie eyes. :)

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Hi,

If you already had a scope with a 2" diagonal and EPs as well as the mak, then I would say it may be worthwhile to upgrade your mak to a 2", but it is a expensive upgrade and the cost of 2" EPs is also higher.

Personally, if I was in your shoes I would spend the money on a good mid priced EP if you don't already have one. I think that would improve your viewing experience more than a diagonal upgrade of any kind.

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