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Dario

First observations with a Mak 127: suggestions to improve?

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Hi everyone!

As I said few days ago in my presentation I recently got my first scope  (skywatcher 127) and over the last days I tried to test It.

Due to impossibility (temporary) to bring the scope in a decent location to make observations, I had to test it from home through a window  (and under the sky of London - not the best at all). So i know that quality is of course affected.

On the other hand, I am sure that the performances are worse than I could expect also under these conditions (maybe you will correct me) and would asks for opinions to improve.

As a (mainly) planetary scope, I did not have a lot of choice: no Moon, Jupiter and Saturn out of my field of view. I pointed at Mars.

First sight, I see the very big central obstruction. I played with the knob of the focus to get rid of the big black spot in the centre of my target and here you are the issues that I would like to talk about:

1) the target became very small (ok) but still was not focus  (very blurry and not a lot of clues to get atleast the shape of the planet well defined - can imagine to find any detail on it )

2) Also the colours did not convince me as no other colour than a light yellow was visible

3) Changing the eyepiece  (10 instead of 25) for a magnification of 150x did not improve the situation: probably the image was even worse, more blurry with more irregular shape than before, no ability to focus at all. Differences from before : bigger (but still much smaller than expected) and very little variation in colours (I believe I saw a bit of orange).

To complete, later, I tried the scope to stars: Orion costellation was visible from my place and tried to all the stars. Although still a bit blurry  (the brightest stars), I had impression of more sharp view, differentiation in colour and better shape  (stars almost like a dot). Moreover, to give you a final idea, Mars (at the best focus I could get) did not appear that much bigger than Betelguese.

What do you think I can do to get better results? Could be a scope problem or some adjustments needed? Unfortunately I have no comparisons. 

Thank you, Hope I was not too long 😅

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I don't think you are basically doing anything wrong.  You are really up against it having to operate in the circumstances you describe.  Even if you are viewing through an open window, the warmer air from inside will be flowing to mix with the colder air outside which will help to make the image blurry.  A Maksutov needs a fair amount of time for the air inside it and also the optics in order to match that of the outside before the telescope will work well.  The things you can do to improve matters are 1) Try to use it outside, 2) allow the telescope to reach equal air temperature and 3) Practice, practice, practice.  You will also need a lucky night when the seeing conditions are good.  Astronomy calls for a lot of patience, we've all been through this!.     Welcome to the SGL "Helpline".    🙂 

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Mars will look small even at x150.

Even in proper viewing conditions - meaning not looking from warm room thru several sheets of window glass (you probably have at least 2-3 sheets of glass there - anything but optical quality) in colder air outside, there will be very few details of mars visible if seeing is not great.

Mars is tough target even for more experienced observers in comparison to other three targets you named - Moon, Jupiter and Saturn.

Best improvements in planetary observing come from optimizing your viewing conditions. It is very important not to have anything between scope and target and to be at equilibrium to ambient temperature. This means that you need to take scope outside and wait for at least 20-30 minutes until scope cools down.

That is like step number one - only once you've done that, you can look for other factors to improve the views (and there are several that you can do "right out of the box" - like not observing across bodies of water, or concrete - if you have park near by - go there to observe)

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1 hour ago, Dario said:

I had to test it from home through a window

1. Hopefully, you at least opened the window.  Viewing through windowpanes is a recipe for blurriness at high powers.  They are going to be far from planar at the wavelengths of visible light causing distortion like a bad lens.

2. Hopefully, the inside and outside temperatures were close.  Otherwise, you're going to get thermal gradients as air rushes through the window to equilibrate the temperature differential.  Those thermal gradients will act like lenses distorting your view.

3. In summary, if you're going to view from inside through a window, open it wide open and allow the temperature inside to reach the outside temperature before observing.  Perhaps running a box fan in the window temporarily would hasten this process.

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Yeah basically what they said ^^

I have a 127 mak and have had it up to quite high magnification on Mars and had some decent results on the back of it. However as Vlaiv says it is not an easy target, especially for a begginer.

The moon is just coming up now and so try some moon viewing before going onto the more difficult targets. The moon can be great fun and I often spend a while on the moon before moving onto planets if conditions allow. 

Finally something which hasn't been mentioned, your 10mm eyepiece is not very good, you should consider changing to something better. My recommendation would normally be a 21-7 zoom eyepiece but keep the 25mm, they are pretty decent and a good spotter for your scope. 

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I'll second all the above !

I bought a 150 heritage dobsonian in early summer, and have been learning with it that it's not just the telescope you need to know how to operate, you also have to learn how to see . Sounds stupid, but getting your eye in line, and at the right distance from the eyepiece , and then keeping both open whilst concentrating on the image from the 'scope ... it didn't come naturally to me.

Wanting to add a longer focal length 'scope specifically for observing planets and the Moon , I just bought a 127 skywatcher Mak. , and if I hadn't already had some experience with the dob, which has half the focal length, therefore half the magnification of the Mak. I suspect I'd have struggled to use it. The greater magnification means the Mak needs to be aimed with greater accuracy , Mars scuds across the field of view faster, and the focus is more finicky too.

Take your time, be patient, use the 25mm eyepiece , let the 'scope cool down for at least half an hour , try to use it outside. And remember you are peering up through a sea of air , conditions in the atmosphere are enormously , annoyingly limiting, but some time a good clear night will happen ...

Heather

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I have to agree about the fact that Mars was maybe not the best target to start testing the scope. Yesterday I was lucky to be back from work just before that the Moon, Jupiter and Saturn were out of my field of view from my place. I tried the scope pointing the Moon and the view was great and very detailed  (although the difficult observing conditions). Maybe it was better than expected. However it was not that great, I have to Say,  for Saturn and Jupiter (no details unfortunately) but of course better than Mars last day with the shapes of both planets  (including Saturn's rings) well defined. I will try to improve the observing conditions (and in future upgrade, I agree that the 10mm eyepiece provided with the scope is not very good ) to try to have better results, good to know that the problem is probably not technical

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