That explains a lot. I had thought that going too high in magnification would make the image blury. I have been able to use my 4.5" reflector several times at about 285X, which is greater than 60X the appeture. What I understand now is that the seeing was good enough to allow me to make Jupiter bigger but I could still only see the same detail as was in the smaller image. Has anyone used the Orion Epic ED-2 eyepieces? I tried one that Dale Hooper had last summer and it looked good. They are $69 and have 20mm eye relief and 55 degree field. The 3.7mm eyepiece would get me almost 400X on my short 10" scope. The 5.1mm would get 496X in my 10" f/10 without a barlow. -----Original Message----- From: Brent Watson [mailto:brentjwatson@yahoo.com] Sent: Wednesday, January 29, 2003 10:32 AM To: utah-astronomy@mailman.xmission.com Subject: Re: [Utah-astronomy] Where is power needed? More like getting a magnifying glass out to look at the 1600X1200. The detail is there, you jst need to make it bigger to see. Brent --- Jim Gibson <xajax99@yahoo.com> wrote:

Brent

It's kind of like when I can't read the text on a computer screen set to 1600X1200 I have no problem when the resolution is set to 600X800; no additional detail just easyer for my old eyes.

Jim

Brent Watson <brentjwatson@yahoo.com> wrote:Jim,

High power above the maximum can sometimes compensate for resolving power difficulties of a person's eye. There will not be more detail there, but sometimes the high power will make it big enough to see. Also, the seeing on vrareeare occasions will allow a "peek" at higher resolution than you might otherwise think.

One word of caution. High power also brings out the defects in the eyeball. You have to be very careful about what you see, and whether it is an artifact or not. Please look up Hershel's use of high power, and his reports of moon creatures. (A famous hoax)

Brent

--- Jim Gibson wrote:

...

Question for Rich Tenny (or anyone else)

I saw the new Televue products (41mm eyepiece etc) you mentioned last night at SLAS at:

http://www.televue.com/WSP2003/NewProdsJan2003/New_at_WSP2003.htm

...

I don't currently have any hi-power stuff like the 3.5mm or the 2.5mm Nagler. I ran this little

program

...

at: http://www.csgnetwork.com/telescopemagcalc.html for a 12" mirror with an f7 focal length and a 2.5mm eyepiece. One of the calculations states that for this setup the "Maximum Useful Magnification" is 600x; however, the 2.5mm would provide 853x. I also recall from a previous conversation we had that someone told you in reference to the Mars opposition that it could take all of the power you could crank. How does all this square? Does the Maximum Useful Magnification mean that everything over 600x (in this case) will go soft? If (big if) I bought a 2.5mm Nagler, could I use it for anything else? I am thinking that such power would only be good for bright planets.

Jim Gibson

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