Fred Ley

Talke about an excellent image. Well done Anthony. Fred

Send the question to the good people at APOD. They might be able to forward it to the sender of the image and you can hopefully end up with your answer. Fred

There is very nice site that talks about the atmosphere and seeing. The size of the air-cells play a big role too. I don't know if most of you have come across this site, but it has a lot of useful information. Here is the link to that site... http://www.telescope-optics.net/induced.htm The link takes one to the section about the atmosphere and seeing. Fred

My 4.8 Nagler works just fine in the 6-inch f/15 system. Naturally the seeing conditions need to be good. I initially concluded that the 4.8 Nagler, delivering 476.25x, would simply be empty magnification. But I have had times where it works and I actually enjoy the image delivered at that mognification. It lacks a bit of that image crispness that a lower magification delivers, but it is well worth the view. The doublet was made in 1972 by A. Jaegers. I may simply pick up one these 3.7's just for the fun of it and see what it will do in my 10-inch f/6.3 SCT. Of course with a focal reducer it can drop down to f/4.5 but I really don't want to start adding more glass to the light path-but it might prove to be interesting. As to Al's eyepieces, my 13mm Nagler that I picked up back in 1984 is my favorite, or one of my favorites. That is a great eyepiece, even though you get the kidney bean effect in it if your eye isn't exactly centered. Of course that remedied by a later model having an extra element added. The older Wide Filed series (65-degrees) are great. I really love the 24mm and the 19mm is nice too. The 32, 40 and 55mm Plossl's are nice in addition. I think I need to buy some newer designs just to see what they do. It should warrant getting a big light bucket too. Just recalled. Some time back I purchased a Celestron 2" 18mm Orthoscopic. When used on the refractor it is just great. The crispness in the image is just there-oh yeah! -Fred

I need to get one of those. With my 6-inch f/15 system it will give me 617.83x and a true field of view of 10-minutes and 41-seconds. I hope that I can find seeing conditions to make the magnification to work. The magnification seems to be just to much. I prefer 30-40 magnification per inch of aperture as opposed to the customary 50-60 magnification. One would think that the 4.8 Nagler eyepiece at 82-degrees apparent field of view would be sufficient, it works just fine in the 6-inch f/15 when the seeing is cooperative. -Fred

Looks like a lot of fun. Fred