BARLOWS AND MISCELLANEOUS COMPARISONS -- PART III

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March 11, 1998 0:00 Mountain Standard

I tried the 9mm Intes Monocentric again. An interesting eyepiece. The views through the other eyepieces basically have the moon looking black or white. To see different shades of gray usually requires use of a polarizer or neutral density filter. Now, this is not an absolute, just an analogy to give you a comparison. With the 9mm Intes by itself, it's basically like there is suddenly 256 shades of grey where there was only black and white before in the other eyepieces. I can see contour to the lunar mountains through the Intes 9mm, and they seem to take on depth or a three dimensional look. The eyepiece has lower light transmission than most eyepieces, so it is like the eyepiece has a moon filter on it when it doesn't. I for some reason like the 3-D optical illusion it seems go give with the Q6 and my set of eyes. I also put the 9mm Intes on top of the Klee for good effect, as long as I was able to ignore the ghost whenever it surfaced. The 9mm Intes is definitely fun to play with in the Q6. I believe the previous owners of the eyepiece disliked it so much that they were willing to sell it for half the price of a new one. I like it with my Q6, so I will be hanging onto it for a long time. It also had adequate eye relief for my needs.

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March 11, 1998 02:30 Mountain Standard

The night is young, and I made some discoveries regarding my telescope.

Finally, I got the scope to reach thermal equalibrium in some good seeing!

It's about time. I just saw rings inside and outside of focus with my Q6! First time seeing has been good enough to give rings. But, then I have been focusing on the moon in the 3mm to 6mm range all night. I used my 5.2mm Pentax XL with the Q6 and got it to focus for the first time.

Tried the 7mm Nagler and the 7mm Pentax XL in the Q6 on the moon. I think the Nagler is a touch sharper, though I cannot see the full field of the Nagler due to short eye relief.

While star testing, I had seen and identified spherical aberration in my Intes 6 f/10. The star test of the Q6 did not look like spherical aberration to me. The size of the central obstruction was the same inside and outside of focus as best as I could tell. No sign of tube currents and little sign of atmospheric turbulence.

It is actually exciting to be able to step out under the sky and not be able to see the stars twinkling with the naked eye. The only twinklers were at the horizon, and they weren't bad.

Turn to page 214 of Suiter's "Star Testing Astronomical Telescopes" book, if you want to see exactly what I saw through my Q6 with the 7mm Nagler. Turned edge! Now finally I know how the scope star tests -- it took a year to find out.

In the last year, I have talked with a friend who owns a Quantum 6. I have also talked with and read the writings of others who have owned Questars or a Q6. And, I own an Intes 6 inch Mak that an experienced observer and telescope reseller considered to be one of the best he had seen for an Intes. I have since come to learn that it is rare to find a Maksutov that passes with a 100 percent perfect star test. None of the other Maksutov scopes I have seen or heard about have passed the star test, they all have some form of spherical aberration or zonal aberrations like a turned edge. So, it is not unrealistic that my Quantum 6 didn't pass with flying colors either. From what I have been told, no Maksutov maker takes the time to properly aspherize the secondary unless he is making the scope for himself; that's enough to eliminate a perfect star test.

My friend with the Q6 owns a 5.2 f/12 Apomax refractor. He says the refractor easily beats the Q6. I assume that's 39 nights out of 40 -- with a big grin on my face. Wishful thinking on my part has me figuring that tonight the Apomax might have been hard pressed to beat the Q6.

Actually, I have noticed that the Quantum 6 suffers routinely from tube currents or thermal inequalibrium, and it is very sensitive to poor seeing. I personally have found that the only routinely good viewing with the Q6 comes with objects at the zenith of the sky. The moon gets up there at times. The Q6 can take as long as 3 hours to reach thermal equalibrium; some nights it never seems to reach equalibrium. A refractor is usually ready to go immediately, or at least within half an hour.

Using a club member's 9 inch Clark refractor last fall, the views of Jupiter blew away anything I have ever seen in my Q6. I was very frustrated with the Q6 last summer when I could only get it to focus at 14mm, possibly 10.5mm on a good night. I found a maximum usable power of 163X on the average summer night to be very disappointing.

So, why do I keep the Q6? First, it does blow away my 80mm UO refractor for all types of planetary viewing on almost any night. The 80mm has chromatic aberration on the moon, the Q6 does not. Second, the Q6 is the most ergonomically comfortable scope I have ever seen or used. I have a bad back and knee, and I used to hate setting up and polar aligning tripods. The Q6 has the best slow motion hand controls on earth. I just take the Q6 outside, sit it on a picnic table, and I am in business. I can sit for hours viewing through the Q6, whereas, chasing the focuser on top of a tripod got to be very uncomfortable at times. In the end, I use the Q6 ten times more than any of my other scopes, because I can sit the whole time and the viewing experience is so much more comfortable. I just wish at times the optics of the scope were better, or better matched to the seeing conditions that I usually have around here. A scope that gets used is worth much more than a scope that sits in the closet; the Q6 gets used. The Q6 is always my first choice to get out; I can set up in about 5 minutes, and I don't have to get out a tripod and polar align.

A very productive night. I now know that with good seeing, the Q6 along with a Klee can make for a great scope for lunar observation. The views were magnitudes superior to the lunar views on the sultry nights of last summer, when I couldn't even focus reliably with a 10.5mm Pentax XL due to the river of heat waves running across the view. As mentioned, last summer I had to run the Q6 at 14mm, which is around 163X. Stacking the 16mm on the Klee and engaging the Q6's internal barlow, I had the scope going at 700X tonight. Granted, at 700X the views were not all that hot, but at least I was able to still focus the scope. A definite improvement. I also found out that the University Optics Konigs proved superior overall for lunar observation.

In summary, regarding the Dakin and the Klee. A friend of mine said to me, "For low power wide field eyepieces I recommend the Dakin, and for higher power eyepieces and planetary type viewing, I recommend the Klee." I have found his advise to be right on. To generalize this a bit more, I would say from experience that the 2X and 3X Televue barlows are like the Dakin in size and in the objects that are best viewed with that type of barlow; whereas, the Klee is unique.

I have read articles in some magazines in which the statement, that barlows don't hurt the image at all, seems to always be mentioned. With some eyepieces and telescope objects, that statement is sometimes true. But, I have noticed from personal experience that the long barlows like the Dakin, 2X Televue, and 3X Televue can and do introduce some serious flaring into the image of most eyepieces when the target is the moon. The Klee is different and does not ghost on the moon.

The Klee goes to great effort to correct many aberrations and to not introduce any new ones into an eyepiece, but occasionally the process backfires, and some eyepieces are horrific with the Klee. When the process does not backfire, the Klee can prove to be a very desirable barlow. The moments when the Klee backfires with an eyepiece many times serves to remove the Klee from the 'top 10' list in most reviews, because the effect is very horrific and very noticable. But, I have found on the moon that the Klee beats everything I have seen so far, and I have supposedly seen most of the good ones if any of the reviews I have read are an indication. The Klee is special, and maybe even unique.

Like everything else in life, your viewing habits would need to be taken into consideration to determine what is best for you.

Darwin Bagley

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March 14, 1998 18:00 to 19:45 Mountain Standard time.

I wanted to try the Dakin and the Klee with my 10 inch f/4.5 dob newt before the moon rise and before the neighbors got around to turning on their lights. If you have read through this whole review, you may be tired of this; and, I must admit that I too had the feeling coming over me just to give up comparisons and enjoy viewing. However, I did also feel that no review would be complete without a look at deep sky.

I started by fussing around in twilight. I found a planet just above the mountains; my best guess would be Mars by the color. A little later the sunset glow settled into a deeper blue, and then I found Saturn up above. Saturn was my initial serious target. The seeing was only average, coming and going; but, then I was aiming at the horizon so what should one expect.

I put my 32mm UO Konig on top of both the Dakin and the Klee. The telescope's central obstruction was clearly noticable in the Dakin and very annoying. The Klee was much better after switching back and forth a couple of times. The Klee didn't display the central obstruction.

I then put the 24mm UO Konig on top of both barlows for a try at Saturn. I could see no difference in the image. I was going to give the Klee the edge, but I figured the ever so slightly extra sharpness in the Klee was probably due to the seeing being a little better when the Klee was in the scope. The Dakin would sharpen up nicely too when the seeing settled.

I then tried the 16mm UO Konig on top of both barlows with Saturn. I liked the 2.4X Dakin with the 16mm Konig at 172X better because it seemed to have a bigger field of view and made manual tracking of Saturn easier than with the narrower field of the 2.8X Klee and the 16mm Konig.

I then dropped in a 7mm Nagler. I couldn't see where it performed any better on Saturn than the Dakin with the 16mm Konig. Both had adequate enough of a field of view to track Saturn.

The Dakin with a 16mm Konig focussed about 1/2 inch farther away from the secondary than the 16mm Konig with the Klee. The Dakin with 16mm Konig was almost parfocal with my 7mm Nagler. The seeing at the horizon was not good enough to determine any of the other sharpness and contrast issues that most people are interested in.

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Now for the item I was interested in. The Orion Nebula. I had never seen more than four stars in the Trapezium, so I was excited to try yet again. The Orion Nebula was fantastic. My wife usually has no interest, but I pulled her out for a look. That's probably the most impressed she has ever been with a deep sky object; the first time she has ever patted me on the back after taking a look at something I have shown her. It usually takes a more 'exciting' object like the moon to get my wife's attention.

The Dakin and 16mm was better than the Klee with the 16mm Konig. The Dakin easily showed the 5th star of the Trapezium (the one they call 'E') when seeing allowed. The Dakin with 16mm provided a nicer wide field of view.

The Klee with 16mm Konig had bigger more bloated stars making double star separation much more difficult. It took longer to see the 'E' star, and more often than not required averted vision. I saw the 'E' star most of the time only because I knew it was there. The difference might be in the magnification factor, though, so I can't in all fairness totally blame the Klee. The Dakin and 16mm combo should give 172X with my 10 inch scope; whereas, the Klee and 16mm combo should give around 200X with the 10 inch. The extra magnification might be enough to explain the extra star bloating with the Klee combo.

I then put in the 7mm Nagler for comparison giving 163X. The view through the Nagler was quite comparable to the Dakin with the 16mm Konig. The 7mm Nagler easily showed the 'E' star during the moments when the seeing stabilized. I still found myself using averted vision at times.

Again, we see that each barlow, the Dakin or the Klee, was and could be the winner depending upon which eyepiece it was matched with and the target object. I assume the same could be said of any quality barlow.

I put up the barlows, took a break, and came back with a 7mm Pentax XL. I could look directly at and easily hold the 'E' star for prolonged periods of time, so I decided it was time to try for the 'F' star. The 'F' star proved to be much more difficult for me because it was relatively close to the 'C' star and the 'C' star is supposed to be the biggest and brightest of the four main stars.

I finally saw 'F'. When the 'E' star was super easy, the 'F' star would be doable. And, there were times of 1 to 2 seconds straight in which both 'E' and 'F' stood out clearly. I was finding the view in the 7mm Pentax XL to be better than those seen in the 7mm Nagler. So, I put back in the 7mm Nagler for comparison. Since, I now knew where the 'F' star was, I found that I could at times detect it with the 7mm Nagler as well. I did find holding the two to be a tad easier with the Pentax XL.

Upon further comparison, I noticed that the sky was blacker through the 7mm XL compared to the 7mm Nagler. The filaments and wispiness of the nebulosity were much easier and more clearly defined in the 7mm XL. It was just darker and more contrastly within the eyecup of the Pentax XL compared to the Nagler. The 7mm Nagler as a general rule does not have enough eye relief for me to be able to see the full field of view without getting closer to the eyepiece than I like to get.

I keep my 7mm Nagler because it's barrel is beat up diminishing its resale value, and because the whole moon will fit within the field of view of the 7mm Nagler while it's being used in my C90. The 7mm XL does not have quite enough field of view to fit in the whole moon. Sometimes it is nice to be able to see the whole moon as if you are on orbital approach.

Another fun observing session for me. I went out later when the moon was way up and the Orion Nebula was in the western murk. I had a very difficult time sensing the 'E' star with the 7mm Pentax XL; only 'saw' it because I knew it was there and was using averted vision at times. The 'F' star was not an option. The wonderful and grand nebulous strands had also all but disappeared. The moon and western murk are not conducive to nebulosity observation and double star resolving.

The 10 inch f/4.5, with a 5.2mm Pentax XL that has a neutral density filter on it, makes for some great lunar observation. There's something pleasing about a wide field of view and the moon in my opinion, if you can get the wide field to focus on the moon. Didn't have problems achieving focus, but the heat waves from the neighbor's house sure were noticable in the view.

Some of you are now asking why I didn't put in my 4.8mm Nagler for comparison as well. I didn't put in my 4.8mm Nagler because I sold my 4.8mm Nagler. I have long eyelashes. I could spend up to 15 minutes a night cleaning the oil off my 4.8 Nagler with the attendant loss in dark adaptation. The Nagler didn't have enough eye relief for my needs. The extra cost of a 5.2 XL was recouped by not having to clean it every night. I have never cleaned my 5.2 XL. The only reason to have a 4.8 Nagler in my opinion is if you need two of them for a binoviewer. You can almost get two 4.8 Naglers for the price of one 5.2mm Pentax XL, a definite advantage to the Nagler. Also, the 4.8 Nagler is much lighter and less wide than a 5.2 XL, so again the 4.8 Nagler would be better for a binoviewer. But, I don't have a binoviewer.

Darwin Bagley

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BARLOW REVIEW -- END OF PART III.