SkyMax 127 vs Dobsonian 200/250

[Bumfluff]

I have a 127 mak which is my only scope at the mo' I am considering a 200/250 dob for better views of DSO's.

I look forward to reading what you decided on and why as I share your current predicament

[Moonshane]

the main difference between the two 8" scopes would be that any eyepiece flaws will be more obvious in the f5 with the shorter/faster tube/optics. also, collimation will be more critical (to get accurate) in the f5 than the dob. this is not a big issue as to get the most from your scope you need to accurately collimate even with an f11 let alone an f6 or f5 and it something you'll need to learn from the start - it's easy too so don't fret.

don't worry about eyepiece quality for now either as any eye pieces will work in any scope as long as the focuser accepts the size. there are two sizes 1.25" and 2". I am pretty sure both 8" scopes accept both types and maybe the 127 only accepts 1.25"? you can spend more on eyepieces than your scope and there's plenty of time to build this up if you want to do so.

the dobsonian mount is not a less stable mount than an EQ5. in my opinion a dobsonian mount will be MORE stable than an EQ5 with an 8" tube on it. I think that the auto version 8" would be good buy as tracking really does help with higher magnifications.

I have a 6" f11 dobsonian and previously had a 12" version (now sold to fund a 16"). the 6" was excellent on planets, moon and double stars and more often than not better than the 12" but when the seeing was really sharp, the 12" was literally jaw dropping. other than the areas mentioned, the 12" (and of course the 16") blew the 6" out of the water. visual observing of most targets (e.g. out of the solar system other than those rare excellent sharp nights as mentioned) is all about aperture in my experience and the more the better.

the 8" tracker would be good if you think you'll find higher magnification tracking a pain (it's not that tricky, especially if you sit) but personally I'd go for the bigger aperture 10" of the ones you mention unless this is a one time only spend and you are unlikely to have any spare funds for some time, in which case go for the 8" auto - this will perhaps allow a few accessories like the mentioned Telrad - highly recommended.

good luck!

I also made an aperture mask for my 16" scope which gives a 170mm f11, central obstruction-free aperture. It's good for double stars and substantially increases contrast on them and the moon but as mentioned, you do lose resolution in the moments of good seeing when they do occur.

[sam mayo]

this thread has already been very helpful thanks, but i am going to be purchasing a new telescope in the next few weeks and i am leaning towards the 10" ssw dob 250p but i will mainly be looking at the planets and is it going to be noticeably better than the 8" 200p,. also if i am going for the 10"ssw dob but i could stretch to the flexitube ssw250p dob which would be best because i might want to try astro photography in the future, i have joined local stargazing society so will hopefully try there 8 "meade looks very similar.,hope u can help many thanks ,sam

never meet and spoken to so many people willing to help and who dont push aside newbies feel like i am apart of a great comunity tanks :grin:

[John]

.... is it going to be noticeably better than the 8" 200p....

On planets I reckon there will be very little in it. On deep sky objects the 10" will show more.

[sam mayo]

okay what about the flexitub 10" and the normal? thanks for reply v helpfull

[John]

okay what about the flexitub 10" and the normal? thanks for reply v helpfull

Exactly the same, optically. The Flextube actually weighs a bit more than the solid tube and needs a light shroud. I'd only go Flextube if I really needed the ability to collapse the tube for storage / transport.

[sam mayo]

okay thanks for clearing that up ill have look at the 8" then just got the voice in my head saying 10" it looks meaner lol(dnt think that ever goes away) thanks

[John]

...... just got the voice in my head saying 10" it looks meaner lol(dnt think that ever goes away) .......

It doesn't go away - a 12" looks meaner still, and it's only a couple of hundred £'s more ........

[paulhutch]

Thanks Twotter,

I am I looking at a world of pain taking on the 10inch as a first scope? would the GSO Revelation plossls work well in the 250 for instance?

Well my first and only serious scope is the 300P Auto Dob (Travel scope excluded), it's best thing I ever bought. Never needs upgrading unless serious app fever sets in and with some upgraded ep's it provides some outstanding views.

[sam mayo]

thanks i didnt need to know that now i am going to have to have a look at the 12" LOL,your a bad influence !!!! :eek: :evil:

oh dear they are very tempting !

(the feeling i get when looking at big scopes is like golem and "his preciouse" ring, is there a cure)

[sam mayo]

i forgot to ask would u recommend buying ep when i get the scope or are the ones supplied satisfactory and can u connect it up 2 a webcam/laptop and see in realtime on screen,thanks,sam

[paulhutch]

I found the stock ep's we ok, nothing special but ok non the less. I use them both in my travel scope as they are much better then the ones that came with it. I bought the 2 inch panaview ep's and a cheap 2 inch 13mm and they make a good scope much better (Although I'm going to get an 8 and 17 baader hyperon, just don't tell the wife!). I have a flashed phillips 880 and you can use that for live view on the laptop but I tend to use it just for observing as I think dew and the laptop don't mix (Also registax is tough to use). If you get the dob then you can treat yourself to new ep's as and when funds allow. I bought the scope because I didn't fancy loosing money every time I upgraded from a starter scope to intermediate to top end. I have no reason to upgrade this unless I start astro photography then we open another can of worms altogether.

[John]

... (Although I'm going to get an 8 and 17 baader hyperon, just don't tell the wife!)....

The Hyperions are nice eyepieces in slow scopes but not great in fast ones, ie: F/5. For £90 (less, in fact) there are better choices around now for fast scopes such as the Celestron X-Cel LX's. For more £'s you have the Nirvana's or ES 82's or you might even consider treating yourself to a Tele Vue Nagler (used perhaps ?). As you say, the 12" Sky-Liner is a great scope and well corrected wide field eyepieces, though not cheap, really allow it to "open up the heavens"

[Leebert]

I have a 127 Mak and a 200p and echo what others have said above. The f5 200p is great for clear views of both planets and DSOs - it is a great all rounder. I love the 127 for the ability to pop it in the garden and get set up in minutes for those brief opportunities between clouds.

I think they are both great. If I was doing it again with my money, I would make the same decision and go for the 200p.

[sam mayo]

.i found another 10 " its the Zhumell Z10 Deluxe Dobsonian Reflector does any1 know if its gd,better or same as ssw dob v.intrested thanks