BARLOWS AND MISCELLANEOUS COMPARISONS -- PART IV

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March 20, 1998 Just after noon.

I decided to pull out my C90 with its mylar solar filter. I used a 90 degree Edmund Amici diagonal to put the eyepiece into a comfortable position, and the diagonal also served to put my head and eyes out of the light path of the C90's finder scope just in case the cap fell off the finder, exposing me to the sun.

The 24mm UO Konig on top of both the Dakin and the Klee, and I could see every spec of dust on the eyepiece. Rotating the different components isolated the dust on the eyepiece as the dust being seen. The Klee emphasized the 24mm UO Konig's blackout problems. There was less blackout and the view was more comfortable with the Dakin. Overall on top of the barlows, there was way too much magnification given the aperature and seeing.

I tried the 26mm Celestron Plossl. It too had a lot of miscellaneous blackout on top of both barlows, but the blackout was more prominent with the Klee. Dust again visible on the eyepiece. Not a nice view.

Apparently, the C90 in the 25mm range brings any dust on the eyepieces into visible detection. I have noticed that fact repeatedly. A scope will bring any dust on an eyepiece into the field of view, but yet put the same eyepiece in a different scope and there is no dust to be seen, even though it is still there.

I then tried to use the 32mm 1.25" UO Konig on both barlows, and then I learned something. The 32mm UO Konig was also blacking out in parts of the view, and then I noticed the shape of the Amici prism in the round view. The Amici prism itself is not perfectly round, and the prism was not masked to make it round, so some of the blackout that I had been seeing in all the eyepieces was due to the diagonal.

The 32mm UO Konig on the Klee actually achieved focus, so I would declare the Klee to be the winner over the Dakin with the 32mm UO Konig and the solar setup. (Reading this paragraph a couple of weeks later, and I wondered what I was saying. I don't remember it being a matter of the scope not being able to achieve the focal plane, but a matter of the heat waves and poor seeing combining to make the image through the Dakin so that it would not snap into focus no matter what I tried -- the edge of the sun always seemed fuzzy and unclear.)

The Dakin was better with the 26mm Plossl and 24mm Konig on the sun.

I then tried the 26mm Plossl, 24mm Konig, and 32mm Konig by themselves without the barlows. I found the views without the barlows to be the best and most detailed. The barlowed views were too much magnification for the poor seeing conditions.

For some reason, of the three eyepieces I found the 32mm UO Konig to provide the most detailed, most comfortable, and the least blackout problems of them all when used by themselves.

I hear it said frequently that barlows do not affect the quality of the image; but, that is just not true. With each of the eyepieces and the sun, the barlows increased the blackout to an unacceptable level. The blackout was much more acceptable when the barlows were taken out of the mixture.

I have not done much solar viewing during the past years due to the fact that we have been at the solar minimum for sun spots. This is the first time in two or three years worth of time that I have gone out to look at the sun and have actually seen sun spots. Maybe they are finally coming back.

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Final summary:

This review is a compilation of many reviews over weeks of time, with a touch of after the fact editing on my part. I have noticed that I repeat myself in spots. I didn't remove the repetitions because they serve to emphasize some of the points that I think to be important.

If you study this review carefully you will notice that I contradict myself at times. That's part of the point that I hope to get across. Some people swear by an eyepiece or a barlow saying it is the best to the exclusion of all else. The reality is that an eyepiece will perform differently in different scopes and on different objects and at different times of the day. The 'perfect' eyepiece or barlow will at times come in second place if it finds itself out of its element.

So, one would conclude that to be perfectly happy a person needs an arsenal of eyepieces and a handful of barlows. Well, that's not the case either. It more realistically should be the case where a person acquires the equipment he needs to do the viewing that he likes. If you have the monetary means to get one of everything, it sometimes can make things a little easier; but, in the end, it's best to have what you actually use. If it sits in a closet or in an eyepiece case and never comes out, then it might be better off in someone else's closet or eyepiece case. Now, on the other hand, someone will hold onto an eyepiece forever in hopes that the right scope can be found for it; and, eventually the perfect scope or object comes along for some fantastic viewing. Contradictions. Such is life.

Well, I hope that something in here will prove useful to somebody. Thanks for reading if you have gotten this far. Time to stop comparing and just go out and observe.

Darwin Bagley

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END OF BARLOW REVIEW.