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Small aperture+crazy stupid magnification! Do you?

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#1 Starman81



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Posted 25 April 2013 - 09:00 PM

I was observing the Moon a few nights ago with my EON 80mm ED refractor and was having a great time all around. I started to push the magnification more and more for the heck of it, to see when the image would break down or the Moon would zoom out of my FOV too quickly. When doing this with my 8" dob it happens probably around 300x-350x. With the EON 80 being a wide field scope, I would think its aperture limitation and shrinking exit pupil would be the limiting factors. Anyways, I was using the Pentax XW 5 & 7 along with TV 2x barlow and also the TV 2.5x Powermate and started upping the power. 143x? Not breaking a sweat. 200x? Still looking quite acceptable. 250x with a 3.1" scope?? Still 'passable', though floaters were prevalent with the 0.32mm exit pupil. Then I went truly wild. 5mm eyepiece + TV 2.5x Powermate + TV 2x... So, 5mm = 100x, so multiply that by 2.5 and then 2 = 500x! Exit pupil 0.16mm! It looked like the entire volume of space was filled with floaters, so much so that I recoiled at first from the sight. It was like looking into a microscope at a colony of bacteria. Ok, so enough dramatizing, what did I learn? Push the power when you feel like it, you never know what will happen. The seeing was only 2-3/5 so that wasn't the deciding factor. I think that up to 250x-300x was probably doable though not perfect, but still pretty breathtaking. Maybe it was because this is a refractor? Or maybe I have a high tolerance to 'murky' looking views? I mainly stick to lower powers in my dob (less than 200x) usually. I don't know. But what I do know is that from time to time, I am going to go against conventional wisdom and see what results.

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#2 WesC



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Posted 25 April 2013 - 11:11 PM

I love putting my 6mm radian in my 2x Powermate and seeing what I can see. Sometimes I get an unbelievable view of Saturn... Sometimes it looks like I'm trying to read a business card at the bottom of a swimming pool! ;)

#3 Jon Isaacs

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Posted 26 April 2013 - 03:55 AM

I love putting my 6mm radian in my 2x Powermate and seeing what I can see. Sometimes I get an unbelievable view of Saturn... Sometimes it looks like I'm trying to read a business card at the bottom of a swimming pool! ;)

With what scope?

The question with Crazy High Magnifications is whether I am seeing more or seeing less. It depends on the object, double stars take the highest magnifications but that generally tops out at about 80x/in, beyond that, it's just fun and silliness.

The highest magnifications I have ever used in such foolish fun is with my 130mm F/5 Newtonian, approximately 1300x, just two big round and quite dim Airy disks...

For actual working magnifications, when the seeing is excellent I use a nominal 821x with my 10 inch Dob for the tightest doubles and similar magnifications for small planetary's with my 25 inch.


#4 beanerds



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Posted 26 April 2013 - 04:54 AM

I have tried my 3mm TV Radian and 2x ultima barlow in my Zeiss telementor and thats 480x , on the moon and jupiter/saturn the views are still sharp , a little dim of course but still sharp . Not bad for only 63mm awsome optics these Zeiss's .
At those magnifications the slightest touch of the focus knob starts an earthquake in the view tho .

I regularly hit 800x plus in my M210 and 3mm Radian , nice views if the seeing allows , jupiter/saturn especially and the IEQ45 is sturdy enough for it to be enjoyable .
It sure is fun .

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#5 Rutilus


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Posted 26 April 2013 - 06:18 PM

When I had the Tak-TSA 102, I once used 900x on Saturn.
The image of the planet was utter rubbish (no surprise there), however I did manage to see the moon Mimas.

#6 petrus45


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Posted 26 April 2013 - 07:11 PM

Now THAT is livin on the edge!

#7 BigC



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Posted 26 April 2013 - 07:53 PM

I stop upping the magnification when the reflected? image of my eye overwhelms the object being viewed ,which seems to occur around 75x per inch aperture under the rare perfect night..

I once used 1200X on my Z12 while trying to visually find the Horsehead and couldn't keep the stars in focus,much less find the nebula.

Conditions,scopes,and eyeballs combine here to make somewhere around 400X the usual limit before sharpness and contrast both fall off a cliff.

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