Size of Planets through scope

[M4lcs67]

Was wondering if anyone could give me some advice?

I posted a while ago about how disappointed I was with the images I recently got with my scope. Being new and inexperienced I had no pre-concieved ideas as to the size of the planets through my 127 mak, so when I finally saw Jupiter for the first time I was rather disappointed.

Now I am not saying I will do it right away as I have only owned this scope for a few months, but if I up the apeture of scope and get something like an 8", would the extra lightgrasp give me a bigger image or am I barking up the wrong tree? Thinking about things in a logical sense I would say not as you are still limited by your eyepieces at the end of the day.

I guess I am just asking for someone to confirm what I really already know.

[cgarry]

What magnification were you viewing at with you Mak?

Cheers,

Chris

[M4lcs67]

Hello, Sorry for being dumb, but I was using my 9mm eyepiece and my 2x barlow. Does that help any?

Thanks in anticipation:)

[Ags]

You are limited by seeing and may struggle to go much over 250x with any scope in the UK. Also bear in mind the image in a larger scope tends to suffer more from poor seeing (so I'm told). Another point to think about is that the image at say 150x is going to get much too bright in a large scope, so you start to need filters to dim the view...

[Moonshane]

generally it's not the aperture that governs the usable maximum magnification it's the quality of atmospheric (and even local) seeing. Generally the maximum theoretical magnification is about 1.5-2x the aperture in mm. so your mak with an aperture of 127mm would in theory be able to get to 127 x 2 = 254x. with a 1500mm focal length and effectively 4.5mm eyepiece you were trying to use 333x which is really a bit too high for your scope - sometimes you might possibly push to this or even higher on double stars or the moon but rarely on planets.

that said, in the UK seeing often restricts usable mag on planets to perhaps 140x-200x no matter what the aperture. I see my best images at these magnifications and only very occasionally more.

an 8" scope would give better views of planets when the seeing allowed it and aperture does provide more theoretical resolution on an object (again subject to seeing, cooling, collimation, eyepieces, observer skills etc etc) but again this is not always visible. A 8" scope is in my view a much better all rounder than a 127mm mak but I'd probably keep both if you can.

[Stargazer51N]

According to the manual for the SLT 127 ...

Maximum useable magnification is 300x

9mm eyepiece will give 167x

So this eyepiece with a 2x Barlow will take you over that

[John]

My largest aperture scope is a 10" and the vast majority of my planetary viewing is still done at 150x - 250x, with the seeing conditions being the main limiting factor as has been mentioned. It's better to have a smaller but sharp and contrasty image than a larger, blurry one.

If it's any consolation this is one of the commonest reactions of newcomers to the hobby after their 1st views of planets, so you are not alone !.

[scoobymike]

I took my Mak 127 to a dark site a few weeks ago, and with a cheap 20mm EP I could see bands on Jupiter very clearly. Couldn't see the 'Great Red Spot', but that was more likely due to it being on the dark side

You're not gonna get views such as you see on tv through this scope, but you'll be surprised how good this scope is for planets.

As said earlier, seeing affects how high you can magnify something - my best views are generally from my 8mm (at 187.5x); 12mm (125x) gives consistently good views, but 5mm, (300x) is almost always a painful exercise - and if 200x is your limit it makes no difference how big the scope is.

If you stick with your scope for the moment, and spend time at the eyepiece, you'll soon pick up more detail as your eyes adjust properly, and you will get some amaxing views.

Good luck, and clear skies..

[barkis]

I think you hit on one important point in your opening post Malc. to quote you, "Being new and inexperienced"

Observing is a skill you develop with time, and it rarely has to do with magnification, but more to do with training your eyes to study an object. Sometimes it is better to use the peripheral areas of your eyes, which is more sensitive to faint details.

John's (Jahmanson) advice is important to follow, and he is spot on about the disappointment felt by others on their first experiences of observing planets. You will have a good time with Jupiter in the coming weeks, as it climbs towards opposition, and nearer the earth.

The planets disc will grow in size, and given decent skies you will get some superb views of Jupiters atmospheric details.

You have a good enough telescope believe me .

Ron.

[Alpha Boo]

Hello to you all here, first forgive me for maybe talking rubbish as I am completely new to everything you guys have spoken about but thought I could give another point of view. I was kindly given a konus 900mm newt. reflector although to me it was huge I have realised that at 114mm it may lack in brightness. I use a 17mm and 10mm ep and have enjoyed my stumble around the night sky with it so much I think I am hooked. I am lucky in that I do experience a good dark sky at night where I live but for me the high point was in fact seeing Jupiter. Ok yes it was small but I wasn't expecting a massive image, but with the 17mm ep the detail was amazing, I even spotted 4 of her moons! This was a first for me and makes me want to learn more. One question I do have is , would I improve my viewing with a better quality E P or am I better of saving my money for a better scope? Good to meet you and be here

[barkis]

Hello to you all here, first forgive me for maybe talking rubbish as I am completely new to everything you guys have spoken about but thought I could give another point of view. I was kindly given a konus 900mm newt. reflector although to me it was huge I have realised that at 114mm it may lack in brightness. I use a 17mm and 10mm ep and have enjoyed my stumble around the night sky with it so much I think I am hooked. I am lucky in that I do experience a good dark sky at night where I live but for me the high point was in fact seeing Jupiter. Ok yes it was small but I wasn't expecting a massive image, but with the 17mm ep the detail was amazing, I even spotted 4 of her moons! This was a first for me and makes me want to learn more. One question I do have is , would I improve my viewing with a better quality E P or am I better of saving my money for a better scope? Good to meet you and be here

You have contributed a nice addition to the thread Alpha Boo, and I'm sure the OP will appreciate it.

Welcome to SGL.

Ron.

[brantuk]

You can get an idea of the field of view if you put your scope and ep details into this website and choose the "visual" view:

http://www.12dstring.me.uk/fov.htm

[M4lcs67]

Thanks to you all for you input/information yet again. There does seem to be a common theme running through and that is the seeing conditions.

I suppose I want instant gratification (blumming newbies eh!), but as alot of you say, the more time I spend observing the more my eyes will become acustomed and therefore the more detail I will see.

Once again thanks to you all.

ps

You probably have saved me from going out and buying another scope when the one that I already have is up to the job. My wife and bank manager will be eternally grateful.

[lukebl]

As others have explained, around 200x is about the maximum you can expect with ANY scope, and it is heavily dependent on seeing conditions.

The amazing planetary images that people on this forum achieve with just a webcam leads newcomers to great expectations. However, the imaging process 'selects' the best from a whole series of frames (often several 1000), and reveals a huge amount of detail that is almost impossible to see visually. However, there are rare occasions when seeing is perfect and you will be truly amazed. These moments are truly rare, at least in my experience of suburban UK. I can only recall one brief moment of perfect seeing during light fog last year when, for a few minutes only, and viewing with a 10" Newtonian at 300x, Jupiter was completely still and really did look like the photographs, with amazing detail showing in the belts. On that occasion your 127 MAK would probably have given very similar views. Moments to be savoured!

[Capricorn]

Get an eyepiece that will give about 150x.

If the barlow in question is the one that came with the scope then it is generally poor.

With the focal length of the scope you can use the standard plossl range and have a good image, so really little point getting another barlow for that scope as you can buy a few inexpensive eyepieces.

I doubt that a 127 will get a usable 300x at any time. Usually they claim 2x dia in mm, so 250x. As the claim for this is now more, I expect others will follow and claim 2.5x dia in mm yet the scope(s) will not have changed. Marketing has to be taken into account.

[Adrian]

I agree with the above. The biggest change was setting my scope up so that I could sit in a chair and be comfortable at the eyepiece. After that I could take my time looking and my whole viewing experience was much better.