Posts Made By: Doug Peterson

I directly star tested the FSQ-N with the new FSQ-ED and can confirm that the new model has slightly less color. However, I do not believe that current owners necessarily will find the difference dramatic and necessarily need to upgrade. The original remains a spectacular telescope in all respects. In fact, a used FSQ-N may well be a best buy.

The Dedicated Diagonal that works so well on the FSQ classic doesn't work as well on the FSQ ED because it rotates with the finder and focuser. The manual shows the Tenth Wave diagonal.

BTW, the 13mm ETHOS on the FSQ is awe-inspiring....

Well I nearly created an interplanetary incident when I walked into OPT wearing the Astromart T-shirt without even thinking about it.

The new Extender Q is optimised for the New Q, I believe that it would not be the right answer for the legacy Q, in fact the ATWB listing says It is not compatible with the original FSQ-106.

I have one for my New Q and it is much more user friendly than the old combo.

The lens system is built into a short 2" extender tube that fits and accepts regular 2" tubes, rather than threaded. In fact the lenses are cleverly built into the tube in such a fashion that your 2" diagonal tube slides around the optics.

I can also report that the new extender Q does noticeably increase the color correction of the New Q substantially. Namely a small amount of red around the out of focus fresnel rings goes away completely leaving just a touch of blue. In focus it is colorless.

It is necessary that heavy diagonals and the Ext Q be very square and tight otherwise a small "color wedge" due to tilt creeps in.

Are you using a prism diagonal? At F 5.6 the prism will inject significant spherical abberation and color. I have seen this on mine.

A Meade ETX 70, the lens had at least 10 waves of zonal error, and no the lens was not in backwards. Doesn't someone look thru these things even once before shipping?

I have both a 60mm and a 78mm Nikon Fieldscope ED and am very happy with their optical quality compared to the competition.

That Larry Niven story where the astronaut comes back insane ... turns out the entire planet was an ocean of human bodies being bred for consumption by an alien civilization that would visit periodically for a harvest.

Zeiss does the same thing by adding a roof prism monocular to the path after the exit pupil. The beauty of the idea is that any telescope can look thru any other telescope, because the output after the ocular is parallel light, collimated.

Anyone can do this, use a handheld finder or monocular "auxillary telescope" to look thru your bino or telescope. The magnification is multiplied, that is if you use an 8x finder to look thru a 10x bino you get 80x. A handy way to assess the star test of your bino.

For what it is worth, premium binos are usually under one wave, even diffraction-limited like a nice telescope: in fact some binos such as the 10x70 Fujinons are so good you can see the nicely formed airy disk and a couple of diffraction rings. It is also a way to assess the color correction of ED/APOs vs achromat binos.

The original Genesis had a fluorite element in the rear doublet along with ordinary glasses; there was significant color. Supposedly the performance was something like an F30 achromat. Mine had noticeable red defocus that gave the first diffraction ring a red/orange appearance. My particlar sample had a small amount of spherical abberation and a touch of color wedge--I encountered someone elses at a star party that also suffered from about 1/4 wave spherical, but no color wedge.

My current NP-101 is flawless in all respects, color correction like a reflector, absolutely superb wavefront.

In between, the objective and corrector have incorporated various special dispersion (SD) elements, but so far as I know, Nagler does not reveal the design specifics. The original Renaissance achromatic petzval glasses were the subject of a patent disclosure and I raytraced the scope from there--it turned out to have an F11 front end and the corrector brought the final color correction to about F8. From there I guessed at the original Genesis and knowing the fluorite element was the third element, optimised a design that was probably "similar" to the Genesis and confirmed performance around F30ish. If anyone has the glasses of the NP-101, I would dearly love to know.

The smartest man on the planet. Too bad he will miss the confirmation of extra terrestrial civilizations. I recall he made the remark that the most likely first contact would occur soon after a planet-bound civilization goes into space, and therefore would be noticed by his neighbors. Then he said he believed we would not have long to wait.