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Planets:

If the seeing is poor, then I normally use my 10 inch dob at 130x (with my 8,8mm). If the seeing is very good and my 8,8mm easily shows detail, then I use my 4,7mm which gives me 255x. I normally don't use the 4,7mm, but I did this saturday, when the conditions was very good.

DSO's:

I don't have any rules when observing dso's. I normally just use the mag that fits the object best.

The moon:

The moon can take a bit more mag than the planets(in my opinion). Sometimes when my 4,7mm doesn't work on the planets, I can still use it to get clear views of the moon.

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4 minutes ago, Victor Boesen said:

Planets:

If the seeing is poor, then I normally use my 10 inch dob at 130x (with my 8,8mm). If the seeing is very good and my 8,8mm easily shows detail, then I use my 4,7mm which gives me 255x. I normally don't use the 4,7mm, but I did this saturday, when the conditions was very good.

DSO's:

I don't have any rules when observing dso's. I normally just use the mag that fits the object best.

The moon:

The moon can take a bit more mag than the planets(in my opinion). Sometimes when my 4,7mm doesn't work on the planets, I can still use it to get clear views of the moon.

Thanks! Just what i was looking for :)

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That depends on the size of the objective or the mirror and on the seeing conditions... regarding your 8" dob, I'd say it's comparable to my 8" SCT.

Generally for planets using up to 200X is about the limit on MOST nights before the image starts to go progressively soft with diminishing results. Quite frequently I can go up to 290X and still have a crisp and details view... BUT on the very rare nights where seeing conditions are exceptional, going up to 406X the views are big, crisp and detailed, these are the nights that come once in a while and you find yourself unable to pull away from the eyepiece.

For large nebulae you want to go as little power or as wide field as possible to see the full nebula, but for smaller DSO objects like some planetary nebular or galaxies 100-200X I find is optimal.

   

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Many of my favourite astro views are found at low to medium powers and with wide angles of view so 25x - 100x perhaps :icon_biggrin:

When I do use higher magnifications, on the Moon, Saturn, Mars and double stars I tend to use between 150x and 400x (I've 5 scopes between 100mm and 300m in aperture). The highest I can get is around 800x but I've never used that with any seriousness. It can be fun on the Moon though pretending I'm an astronaut preparing to land :icon_biggrin:

On Jupiter I find 130x - 250x is a more useful range even with my largest scope. The nature of the features on that planet do not respond as well to very high magnifications and I always prefer a smaller, crisper image to a larger, slightly blurred one.

The seeing conditions are the big arbitrator here. On those very rare occasions when they are near perfect you can throw almost insane power at a target. Another occasion, same location, scope and target and 100x times is failing to deliver any clarity. Most often the conditions are good to middling so you pick your magnifications accordingly to find those that frame your target nicely and deliver a sharp and contrasty view.

Magnification and telescopes is a more complex subject than you might initially think. This is worth a read:

https://starizona.com/acb/basics/equip_magnification.aspx

 

 

 

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As John says. I also tend to prefer lower magnifications.  Some observers like to use the maximum they can get away with;  I tend to use the minimum I can see detail with and do also prefer a smaller sharper view. The moon and doubles take the biggest magnification and i have occasionally used 500x or more on these objects.  anything else though and a sharp image at more than 250x is a rarity in the UK and to be savoured.

 

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3 minutes ago, Mathyas said:

Woah. Thats pretty damn high. That must be truly beautiful.

I think thats the issue - the views don't necessarily get more wonderful at higher magnifications. Often just the opposite :icon_biggrin:

When using these very high magnifications a load of other issues come into play as well - tracking an object becomes more challenging, touching the focuser leads to more vibrations, moving your feet near the scope leads to vibrations, small puffs of wind suddenly spoil the view, etc, etc.

Observing at lower powers is often a more satisfying experience :icon_biggrin:

 

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4 minutes ago, John said:

Observing at lower powers is often a more satisfying experience

I know John. Been there :D Love the view that you get on many open clusters!!

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Very much depends on the scope and the eyepiece. Using refractors as a basis you can buy a 127 achro, a 127 APO triplet and from AP a 130 Star Fire

Now they are all about the same size and people will give the standard 2x diameter. But what you see in the Star Fire will massively outweigh the view in the 127 achro. Same on reflectors I would expect a 10" Orion Optics UK to perform significantly better then a 10" Skywatcher, pay for a custom built 10" mirror and likely an improvement over the OO.  Wonder how the hyperbolic Hubble optics mirrors work, the HST is a hyperbolic, so I am guessing better then the "standard" parabolic we buy now.

Where do you define the cut off point for "blurry". I want a good sharp image and size is less relevant, if you have the opinion that bigger is better immaterial of image then who is right. It is a different criteria.

But if you want magnification then Skywatcher, GSO mirrors etc are out of the equation. You need to be looking at premium mirrors, OO, Zumbuto, basically custom or hand built. Also you will likely have to match eyepiece to mirror, as in buy a Delite and a Delos and compare the 2 - one will be a little better then the other, just which one is the question, then maybe try a Nagler, then an Ethos. That is likely close to, or over, £1200 to determine which eyepiece manages to work best for the optics.

 

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Most of the time on the moon I can use 212x. 286x is often usable too but with maybe 1/2 the quality of  212x with 8 inches reflector. For jupiter I have 143x which is usable most of the time, clean, it will give a better view then 212x. For the nebulas, clusters, I like to switch between 31x, 40x, 55x, 80x

I also use 212x to look at the center of clusters, just for the sake of trying it. I notice, higher power will sometimes reveal really faint stars only visible with averted vision at lower power, of course the resolution is bad, but it can help to validate things.

If this can help.

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I generally don't pay attention to magnification.  I pay more attention to exit pupil.  I tend to get my best high power views at no less than a 1mm exit pupil.  Below that, floaters become an issue and the image tends to become grainy for me.  1mm EP corresponds to my aperture.  So, about 70x for my AT72ED, about 125x for my 127mm Mak, about 200x for my 8" dob, and roughly 380x for my 15" dob.  Given my typically steady Texas skies when I observe (usually a couple of days after a front passes and high pressure settles in), I don't notice much difference in the clarity of the views between the scopes.  That's why I don't try to push the power on my smaller scopes, it just doesn't pay off.  Sure, the refractor has the cleanest views being unobstructed, but aperture clearly rules at high powers to keep the exit pupil reasonable sized.

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To my eye, the smallest features on planets become easy to pick up at 240x. To respect the usual limits on exit pupil, that calls for an unobstructed 120mm scope for a 1/2mm exit pupil, or a nine to ten inches obstructed scope for the standard 1mm pupil.

That seems to justify why Sky-Watcher has so much success with their 120mm apo doublet, and why Takahashi makes a 120mm triplet, seems this is where aperture becomes "big".

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I don't observe planets. The moon I like to observe at a relatively low (160x) power to enjoy the more encompassing view. I never really get serious about lunar observing I just enjoy the views of our closest neighbour.

DSO's anything from 75x up to about 400x depending on object size, type and brightness. 

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as steve above realy, which it would be with both having 20" mirrors. my most used ep's are my 13e/8e which gives me 184x and 300x. if im looking at planets i will use my 5mm pentax which is 480x. a couple of weeks ago i did look at jupiter at 960x yes it was very big but not much detail, but the moons had lovely colors :headbang:

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For practical reasons when buying eyepieces, I work on the theory of matching the eyepiece to the telescopes focal ratio for the first high powered eyepiece.
This option works well providing 200x power on our scope, with a 1mm exit pupil.

However not all images are perfect using this eyepiece. Nothing wrong with the eyepiece or the scope, it will be the conditions, I just choose this method because I know the telescope works, and works well at 200x power, the size of the aperture.
Other theories suggest twice the aperture, so 400x power with a 3mm eyepiece would suffice, it can be done, I have even Barlowed my 3mm on the Moon, thats 800x, but the results would not be stunning on much else up there

As others have already pointed out, work from say 6mm to  your 38mm Panaview and generally under the same conditions, the image gets sharper, more detailed (to a limit ) with each  increase through the focal length of the various eyepieces, but inevitably the image gets smaller with each step. 
Go in the other direction, and the image will appear to get closer, larger, but diffused, less detail, and with a narrower  field of view, and your limited to eyepieces lower than a 6mm on a Skyliner.

As for which magnification do I use?........... the one that provides the sharpest detail.
All my eyepieces provide good images, but one of them will be more useful/purposeful on the night, fit for the task as it were.

 

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  • 3 weeks later...

In my SCT, nebulas work best with 40mm and 31mm. That is 57x and 73x, or roughly 3.6 and 2.8 exit pupil, respectively.

24mm and 17.3 are for star clusters (not globulars)

Globulars work at 17, 13, ocassionally (seeing permitting) 11mm.

Galaxies (just started on them) so far 24mm and 17mm.

Planets - Jupiter 17mm (130x) average seeing, 170x (13mm) if seeing is good. Saturn up to 11 mm (200x). 250x if seeing allows.

Moon...just push it then back down.

 

8 inch dob works out differently, I suspect, due to differences in exit pupil. Brigther image at lower powers, harder to push high mags due to no tracking...

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In my view finessing over magnification can be a distraction from the more important business of looking. Too much magnification will always degrade the view. Too little, within reason, won't diminish by much the details you can find.

Olly

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Yep, I'm with Ollie on this one. Looking is the key and to that there are many other factors too.

for good "looking", you need to be relaxed and comfortable at the eyepiece. You need time for your eyes and brain to see what is being presented.

a lovely sharp image reduces the time needed to see and enables you to relax and see more too. 

Time is a key factor, give yourself plenty. Binoviewers are great if you want to increase time, less eye strain. Try an eye patch for cyclops viewing. All can increase time!

Quality of eyepieces too, they are not all the same. Good quality low power EPs really do earn their money. You get the clarity plus darker backgrounds that allow the detail to be seen more easily.

magnification is overrated and only a small part of the observing equation.

comfort can be increased by a nice stool or chair. How tired or awake you are at that time. Focusing your mind on the task in hand. How hot or cold you are feeling. Etc etc. Many, many factors that in the end are more important than magnification.

That's my view anyway,

Alan

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I generally think in terms of either getting the right true field of view to frame a target or in terms of exit pupil to get the ideal contrast for a target. Having said that if measured in terms of magnification, I usually observe along the following lines with the vx14...

59x - 153x for most dso's

106x - 230x for planets

153x - 307x for the moon, sometimes 409x

153x - 409x for doubles, sometimes have gone to 526x for doubles at hight altitude in good conditions

When conditions are  bad and/ or if a target is low then magnification is limited but for example on the moon 307x is usually fine

Edit... for completeness with the st80 I usually don't go past 100x, the st120 usually up to 150x, and mc127 usually up to 190x.

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