Change MAK 150 for FRAC. ?

[pluton]

Hello,
I currently have a Maksutov Cassegrain model SW 150/1800, I have a good chance of acquiring second hand one of these two refractors, a SW ED100 F9, and a Celestron Omni XLT 120 F8.3 acromatic and I would like to know your opinion if it really deserves the worth changing the Mak 150 for any of them, obviously the Celestron Omni is much cheaper than the SW ED100.
At the lunar level-planets that would be compared with the Mak 150?
In solar observation (white light)?
For the deep sky I do not ask you since from my usual place of observation DSO almost impossible to realize, too much light pollution ..

Mak 150 for Frac 100ED or Achro, 120 ?

it really costs me a lot to reach 200X on different nights, sometimes I have even been outside the MAK for up to 2 hours, I am talking about this summer, on the other hand I am a person who does not have much time to observe, maximum, let's say one hour ... maybe the refractors are better in this sense, that is, their cooling time is less? I, by my way of observing, prefer a telescope that can sacrifice to the backyard, have dinner and start observing.
I live in a place where in winter the temperature drops during the evening and the night enough degrees ...
Some time ago I had an 8 "dobson and a 10" SCT and never, I could never have a sharp image, and still, she was always trembling ..., and the telescopes left enough hours outside, I think I prefer a more stable and sharp that a shaky and somewhat blurry image ..., I do not know if this would be provided by any of these refractors ..
Thanks in advance
Paul

[Anthonyexmouth]

the ed100 will be quicker to set up but less power with the same eyepiece. the mak will stomp over the ed100 for planets but for solar the ed100 would be better. they're different scopes for different uses. 

[dweller25]

Have you tried insulating the Mak with a couple of layers of Reflectix ??

You may be pleasantly surprised.....

 

 

[vlaiv]

Sorry, but need to ask something - how confident are you that you can distinguish seeing effects on particular night vs thermal stability problems?

You mention that you had trouble with both 8" dob and 10" SCT, and now with 6" Mak.

While Mak does have thermal stability issues, I believe that these are far less damaging than initial cool down and seeing itself.

Before deciding on step down, as both choices would be step back on your current Mak in planetary observing, try to see what is really going on - leave scope outside to reach ambient temperature for an hour or a bit more before observing (even when it is still warmish) if you otherwise keep it in a warm house. If this helps, maybe look into outside storage for your scope - closer to ambient, this way it will be initially thermally acclimated much quicker. Look at defocused star pattern and see if you are indeed experiencing tube currents and thermal instability rather than regular seeing problems. Also try to optimize for planetary observing as much as possible (look for heat sources unrelated to scope - like nearby houses, large concrete surfaces, whatever might give of thermals at night and try to position yourself as to be the least effected by those).

[RT65CB-SWL]

As per @Anthonyexmouth says above, quote: "...the mak stomp over the ed100 for planets but for solar the ed100 would be better." I have yet to find the OTA satisfies or does everything. If you can afford to keep your SW Mak 150/1800 and purchase the ED100, I think you will be surprised how different the views are in either type. One reason I have one of each, albeit on a smaller scale.

[Louis D]

I have a 72ED mounted on one side of a DSV-2B mount and a 127 Mak on the other for my grab and go setup.  They complement each other nicely.  Wide and sharp at lower powers for the frac and narrow and sharp at high powers for the Mak.  You don't specify where you live, but unless you're in the desert where nighttime temperatures can drop 40 degrees F overnight in the winter, just about any scope should reach thermal stability in an hour or less.  The exception might be if you're in Saskatchewan where nighttime temps can hit 40 below zero (C or F) and the scope was stored indoors.  I would try storing the 150 Mak in an unheated garage or similar to reduce acclimation time as well.

If the 120mm acro was an f/12 to f/15, it might perform well on planets.  At f/8.3, it just kind of middling.  Not awful at high powers like an f/5, but not terrific like an f/20.

[pluton]

Thank you for all your opinions and advice, I really do not have the experience to differentiate seeing or thermal problems, the Mak is always in a garage on the outside, it is not usually hot or very hot inside, sometimes I have had two hours outside before observing, and if, around me I have a lot of houses and streets without trees, a lot of concrete and cement ...
I know that maybe it is not the best place to observe with high mag. I have never been able to exceed 180X or 200X, I personally with this magnification I see few planetary details ... the Moon is another story, with 150X there are nights that I see things precious, the DSO I do not even mention it ...
regards
Paul

[Cosmic Geoff]

No harm in buying an ED100 if you want one,  but personally I'd keep the Mak. It ought to be a fine planetary scope.

I always found visual views of the planets somewhat of an anti-climax.  Eventually I decided to give planetary imaging a try, and I soon found that I could see more detail this way (thanks to the wonders of digital stacking and processing) than by visual observing.   Check in the Planetary Imaging section of the forum to see what can be achieved.

[dweller25]

15 hours ago, pluton said:

Thank you for all your opinions and advice, I really do not have the experience to differentiate seeing or thermal problems, the Mak is always in a garage on the outside, it is not usually hot or very hot inside, sometimes I have had two hours outside before observing, and if, around me I have a lot of houses and streets without trees, a lot of concrete and cement ...
I know that maybe it is not the best place to observe with high mag. I have never been able to exceed 180X or 200X, I personally with this magnification I see few planetary details ... the Moon is another story, with 150X there are nights that I see things precious, the DSO I do not even mention it ...
regards
Paul

Hello Paul,

It sounds like you have a similar issue to me - I generally struggle with "poor seeing" - now this can be a number of factors :-

1. The Jetstream - nothing you can do about that except wait for another night.

2. Scope not cooled - best way to cool your Mak is take off the front and rear caps and point the OTA towards the ground to allow any warm air to escape OR insulate the OTA so cool down is not an issue at all.

3. Thermals from the concrete ground or buildings in the direction you are looking - if you observe on concrete spray it with water to cool it down - better still change to a grass location and away from looking over buildings.

The 100ED refractor will be very close to the 150mm Mak for planetary and lunar views and will thermally stabilise faster, giving sharper images and will be good for solar too, so it's probably a more suitable scope for you. Personally I would avoid the 120mm Achromat as it will have chromatic Aberration.

At the moment the planets are very low - at least in the UK - not sure where you are?? - so that will always compromise the quality of views.

Good luck

 

[pluton]

Hello again
Thank you for your answers, all of them very interesting, and educational, before the MAK 150 I had your little brother MAK 127, for the ambition of having greater aperture, I changed it for this MAK 150, crass error, since this is heavier , more time of cooling, more expensive, and everything in exchange for little, since both gave me the same magnification, I have never been able to pass the 180X-200X without losing a lot of image quality ... now they have offered me second hand to Orion MAK 180/2700 and the seller has told me that this is great for planets and Moon, but I am a little fed up with this type of telescope ... also why I want more weight, volume and aperture but I can exceed the 200X as much ..?

Paul

[dweller25]

My favourite scope type is a refractor ?

[nightfisher]

2 hours ago, pluton said:

Hello again
Thank you for your answers, all of them very interesting, and educational, before the MAK 150 I had your little brother MAK 127, for the ambition of having greater aperture, I changed it for this MAK 150, crass error, since this is heavier , more time of cooling, more expensive, and everything in exchange for little, since both gave me the same magnification, I have never been able to pass the 180X-200X without losing a lot of image quality ... now they have offered me second hand to Orion MAK 180/2700 and the seller has told me that this is great for planets and Moon, but I am a little fed up with this type of telescope ... also why I want more weight, volume and aperture but I can exceed the 200X as much ..?

Paul

The Mak 180 is a more specialist telescope, very demanding but when its right very rewarding, i would stick with the 100ED its a scope that would get a lot more use than a 150 or 180 mak 

[Stu]

2 hours ago, pluton said:

Hello again
Thank you for your answers, all of them very interesting, and educational, before the MAK 150 I had your little brother MAK 127, for the ambition of having greater aperture, I changed it for this MAK 150, crass error, since this is heavier , more time of cooling, more expensive, and everything in exchange for little, since both gave me the same magnification, I have never been able to pass the 180X-200X without losing a lot of image quality ... now they have offered me second hand to Orion MAK 180/2700 and the seller has told me that this is great for planets and Moon, but I am a little fed up with this type of telescope ... also why I want more weight, volume and aperture but I can exceed the 200X as much ..?

Paul

If you are not happy with the 150, don't go for the 180! You will have more of the same sort of problems.

I had a C8 Edge for a while. When I compared the views through it with those through my Tak, the Tak normally presented stable planetary images, not overly colourful but there was plenty of detail to be drawn out. The C8 tended to show more unstable images, coming and going as the seeing varied. It would vary from worse than the Tak to better than the Tak in terms of resolution and detail, and the colours on Jupiter certainly were much easier to see in the C8. I found the Tak more relaxing and enjoyable to view through, which is one reason I still have it! If i could take the image stability of the Tak with the colour and resolution of the C8 I would have that please

[mikeDnight]

Forget the 120 achromat as its the worst of the three. If you could afford to buy the 100ED while at the same time keeping hold of your Mak, you could spend some time using both alongside eachother. Both are great telescopes, but you might find over time that you prefer using one over the other. If that's the case, then you could easily sell the scope that is used less.