Monday, December 29, 2003

More On the Photon Instruments Refractor



I had mentioned a few days ago that the diagonal that came with the scope seemed a bit loose. I pulled out the micrometer and measured the inside diameter of the focuser, and the outside diameter of the diagonal. My best estimate for these is 1.994" and 1.992", respectively. A discrepancy of 2/1000th of an inch isn't enough to cause a problem. So why does it rock back and forth?



The focuser is actually a fairly large tube with a "collar" threaded into it. The collar is the 2" diameter component--but the collar's bearing surface is only a fraction of an inch deep. Once the diagonal has slipped into the collar, it is unsupported beyond the collar. I believe that this is what causes the diagonal to rock back and forth. It would take a fairly minor design change to correct this--make the collar perhaps 1.5" deep, and the diagonal would be fully supported. Fortunately, the collar is threaded, so it would be an easy change to make. Had I an engine lathe, I would just whip one out.

Thursday, December 25, 2003

Clear Skies! Finally!



I dragged my Photon Instruments 127mm refractor out this evening--stars, finally! The first look at Saturn was a bit disappointing--then I remembered that this is a big piece of glass, and it has to cool.



After about 30 minutes of excruciating cold weather (I am from California, remember), I was no longer seeing dramatic changes in image. With a 9mm eyepiece (127x), Cassini's Division was visible, although not spectacularly dark. For fractions of second, I could see a dark gray line all the way around the rings, at the ansae, and in front and behind the planet. At least at times, I could see a dark brown stripe in the planet's clouds. Turbulence seemed to be the limiting factor, not the optics. Going to a 6mm eyepiece (190x) did not improve the image in any obvious way. Trying to go above 190x was a waste of time because I am still struggling a little with balance issues on the mount.



Relative to the Ranger, I'm not sure that I am seeing any more detail (in spite of dramatically more aperture), although the image is quite impressively brighter (as well it should be--the Photon has more than three times the light gathering area).



Chromatic aberration? Yes. There is a definite purple fringe to Saturn's rings--something that I don't see in my reflector (of course--the virtue of reflectors), and somewhat more noticeable than in the Televue Ranger--but I haven't done a side-by-side comparison yet, so I can't give you anything more precise than "more." I will say that while I can see the purple fringing, I am not sure yet that I would call it objectionable. It is certainly time to try a Minus-Violet filter, and perhaps a Chromacor, to try either masking or correcting the aberration.



I looked at the Orion Nebula (M42) as well. I can't say that I saw a lot more through the Photon Instruments refractor than I can see with my Ranger, but then again, I was looking through the Ranger in the backyard, which is considerably darker than the front yard, where I had the Photon set up for observation.



One note about the mount: because I have it mounted on a Cave Optical equatorial mount intended for a reflector, the eyepiece on the Photon is down very low--and my neck feels it. The Photon needs an equatorial mount with enough tripod height adjustment to get the Photon up a couple of feet higher into the air.



I would say that the Cave Optical mount is certainly adequately steady for the Photon (unlike the 8" reflector that I usually have on it). No surprise; the 8" reflector weighs 31 pounds, and the Photon weighs 14 pounds.



I knew that I would need to replace the Cave Optical mount at some point, but perhaps sooner rather than later. I need to polish up the Cave Optical mount, and find someone who is restoring a Cave telescope who is willing to pay for a collector's item like this. Its value to a collector far exceeds its value to someone who needs a working equatorial mount.



One aspect of the Photon that was a little disappointing is the 2" diagonal that came with it. I'm not sure if perhaps I need to do some adjusting, but it did seem as though the diagonal was a bit loose in the focuser. This meant that even a little pressure on the diagonal caused significant image shift. I would really like to try using the Photon without the diagonal, but that would require me to lie supine to look through the eyepiece! Don't take this as a slam on the Photon Instruments scope; it isn't built like a Televue or an Astro-Physics, nor is it priced like them, either.



I will try to do a side-by-side comparison of the Photon and the Ranger tomorrow night (weather permitting). At least my initial impression is that the Photon, in spite of its clear advantage in aperture, doesn't do an obviously better job of revealing detail on Saturn than the Ranger. (Of course, I haven't had the chance to find out what really good seeing conditions might do for the Photon.)



The Ranger is cute and compact, and if it were not for the problem of an equatorial mount, the Ranger would be far more portable. Instead, the Ranger is only somewhat more portable. Still, the Photon will fit into my Malibu, and once I get a more modern mount, I should be able to move the whole collection of stuff to a dark sky site without any real struggle.

Tuesday, December 23, 2003

The Photon Instrument 5" Refractor Arrived Today: Snow Should Start Falling Shortly



All you skiiers in the Boise area should thank me. We had clear skies a couple of nights back, but since the new telescope has arrived, the clouds are solid, and it looks and feels like snow will fall this evening.



In terms of bang for the buck--especially impressive bang for the buck--it's hard to beat. It looks good, and what little chance I have had to try the optics so far, seems decent. There's an American flag flying a few hundred yards from us in one of the common areas of our subdivision. I can't count the stitches on the seams, but I am not far from that. A detailed test report is going to have to wait for clear skies.



Unfortunately, I have no 2" eyepieces to really try out the wide field capabilities of this scope, but I suppose that I will remedy that situation shortly.



Mounting it on the Cave Optical equatorial mount did not turn out to be too difficult. The tube rings use 6mm thumb screws, but they were too short to go through the Cave Optical saddle, so I had to run out and buy some 6mm hex head screws, and I borrowed a couple of washers from the neighbors next door. It is certainly quite sufficiently steady for visual or photographic use.

Saturday, December 20, 2003

My Reflector Isn't As Overweight As I Thought



I mentioned a few days ago that my 8" f/7 reflector needed to go on a diet, so that I could get it light enough to fit on a Losmandy GM-8 equatorial mount--and get fully into the 21st century.



I went out and bought a bathroom scale today--and I discovered that it wasn't as overweight as I had thought. The entire OTA (optical tube assembly), including the rotating ring assembly, is only 31 pounds. Going to a carbon fiber composite tube might well get me down to 20-22 pounds--light enough for the GM-8! This is encouraging.



I'm still trying to figure out whether to tackle a more dramatic change. Right now, I have an ancient 1.25" focuser, and a 1.83" elliptical diagonal. It is tempting to switch to a 2" focuser, so that I can use wide field eyepieces. If I go to a low profile focuser, I can reduce the diagonal to 1.3", reducing lost light and diffraction damage to the image.



The downside is that just about all the low profile focusers have very limited range. My current rack and pinion focuser has 3.75" of travel--enough that I can very comfortably use a camera as well, and still have the focal point inside the camera. Low profile focusers generally make you trade off focuser travel for overpenetration into the tube, possibly adding a new set of diffraction problems.



Anyway, there's no urgent need to make a decision right now. I just have to figure out what to do before replacing the current tube. If I am going to drill a bunch of new holes, I would rather do it in the current fiberglass tube, which bears the scars of an unfortunate incident involving my daughter, our Mitsubishi, and the garage.



Oh yeah, feel free to throw money in the tip jar for that Losmandy GM- 8.

Thursday, December 18, 2003

A Crisp, Clear Night in Boise



This is the first such night that we have had here in Boise in some weeks. I was able to drag out my 8" f/7 reflector for the first time since I obtained an easier to use laser collimator. Unfortunately, the atmosphere was still pretty turbulent (or perhaps those were tube currents inside my telescope).



The temperature contrast was strong enough that I could see the focus of the mirror changing. Over a period of about 30 seconds, the telescope went from perfectly focused to a bit fuzzy, because the temperature was changing the shape of the mirror. Saturn is an especially good target for this sort of change, because you have crisp lines (such as Cassini's Division) that you can see blur.



At 157x (9mm orthoscopic), Saturn was crisp, although somewhat small. The Cassini Division was more gray than black at the ansae (the extreme left and right sides of the rings), and only occasionally popped into view in front and back of the planet. I could see at least one cloud band on the planet itself--a medium brown against a very, very pale yellow body.



At 236x (6mm orthoscopic), everything started to fuzz up, with even the ansae portions of the Cassini Division only appearing briefly as the turbulence calmed down. At 283x (5mm ortho) and 353x (4mm ortho), the image wasn't any worse, just larger.



I used some of the money from the PayPal tip jar (thanks!) to pay for a slightly used Photon Instruments 127mm f/9 achromatic refractor this morning. With a little luck, it should be here next week, when I have a whole week off work.

Monday, December 15, 2003

Speaking Truth to Power



This Reuters news story leaves me uncertain whether to call this tactless and rude, or what the Quakers used to call "speaking truth to power":
VATICAN CITY (Reuters) - U.S. Hip Hop singer Lauryn Hill, from a stage used by the Pope, has shocked Catholic officials at a concert by telling them to "repent" and alluding to sexual abuse of children by U.S. priests.



The broadside came during the recording on Saturday night of a Christmas concert attended by top Vatican cardinals, bishops and many elite of Italian society, witnesses said.



Hill made her comments when taking the microphone to sing at the concert, held in the same huge hall and stage Pope John Paul uses for his weekly general audiences and other events. The Pope was not present.



"I did not come here to celebrate the birth of Christ with you but to ask you why you are not in mourning for his death inside this place," she said according to a transcript of her statement run by the Rome newspaper La Repubblica.



...



"God has been a witness to the corruption of his leadership, of the exploitation and abuses ... by the clergy," she said.



This was an apparent reference to the scandal in the United States last year over the sexual abuse of children by priests.
Alas, not just in the United States. Yes, it was just a few Catholic priests engaged in these crimes against innocence--but too many of these crimes were covered over by archbishops. The Catholic Church needs to do some serious penance for ignoring these crimes.



The hierarchy also needs to ask why they were prepared to ignore and tolerate homosexual actions within the priesthood for so long, when the Church's public pronouncements clearly recognized that homosexual action is contrary to the Bible.

Saturday, November 22, 2003

The Joys of a Good Refractor



I was just outside looking at Saturn with my Televue Ranger. It's in the low 20s, crystal clear, and not very turbulent. I hauled out the Ranger because Saturn is still too low in the east for me to get with my 8" reflector--the disadvantages of living in suburbia. This was also a chance to try out the 4mm University Optics orthoscopic eyepiece I just received in the mail. (I have been doing business with University Optics since 1971--I have nothing but nice things to say about them.)



I should explain. About ten years ago, I received a no-name 4mm orthoscopic eyepiece as a gift for helping a friend find a buyer for his Coulter 13.1" reflector. The no-name was a little dirty, and you could see the dirt when you looked at bright objects. I decided to take it apart, and clean it.



It turns out that there are many ways to reassemble an eyepiece. An orthoscopic, at least a true Abbe design orthoscopic eyepiece, consists of two chunks of glass: an eye lens, and a triplet field lens. Neither of these are symmetrical, so there are four possible ways to put the eyepiece back together.



When I was done, the lens wasn't really any cleaner--and it was no longer a 4mm focal length eyepiece--more like a 5.5mm. I bought a 4mm orthoscopic that someone had just bought--and discovered had too little eye relief for them to use while wearing glasses, so I was able to buy it for $10 off the new price.



I was about ready to sell the dirty no-name orthoscopic cheap to anyone with the patience to clean and reassemble it, when someone gave me directions on how to reassemble it correctly. I took the no-name apart, cleaned it, and reassembled it. Voila! It is not perfectly clean, but there's only one obvious dirt spot now, and it is again a 4mm orthoscopic. (I'll be quite happy to take $25 for it, shipped anywhere in the U.S. or Canada.)



Anyway, back to the story of chattering teeth and my dog whining about the cold in the backyard. As Saturn rose, and less and less atmosphere was in the way, more and more detail became apparent. The joy of a well-made refractor is that it gives such an astonishing image, even at relatively low magnification.



The 4mm orthoscopic (120x in the Ranger) was just beginning to give hints of the Cassini Division at the ansae when it became too cold to stay outside--and I could see differing cloud bands in the atmosphere of Saturn. This is a moderately demanding task in many reflectors of 6" aperture--and in a refractor of 2.7" aperture, all the more impressive.



Using a 9mm orthoscopic and a 3x Barlow took me up to 160x. The image was beginning to lose sharpness at this point, but not enough to make me give up on it. The contrast drops as you increase magnification, and so the Cassini Division was a little less obvious. The cloud bands in the atmosphere were a bit less crisp as well, but still noticeable.



The Ranger is a semi-apochromat--not completely color-free, but much better than a typical achromatic refractor, though a bit inferior to a true apochromatic (color-free) refractor. I am attempting to purchase a Vixen 102S from someone in Spokane at the moment--this should provide a dramatic leap up in resolving power and magnification. (Then I have to find a buyer for the Ranger.)



If you are at interested in refractors, you may find this review I wrote several years ago of the Televue Ranger of interest. Like nearly everything I write, I was unable to get it published anywhere.

Monday, November 17, 2003

Thanks For The Contributions



For those who are dropping the occasional small contributions into the tip jar (the button marked PayPal Donate on the left, a little below my picture)--thanks! It makes it a bit easier to talk myself into adding content here. The money is going to several good causes: I've made some contributions to the fund that is defending Missouri's new concealed weapon law, and I just used some of the money in the PayPal jar to buy a 4mm orthoscopic eyepiece over at astromart.com. (Astromart.com is a place where amateur astronomers buy and sell used stuff--I was able to pick up an almost new University Optics 4mm orthoscopic for $50--new they cost $59.95.)



I have an irrational hankering for a Televue 102 apochromatic refractor, so I guess I better put up a lot of valuable content here.



In case you have ever wondered about PayPal--it is a secure method of making or receiving small payments or contributions online--as little as one dollar. You can link your PayPal account to a checking account, a savings account, or a credit card. Balances in your account earn a pretty decent money market balance.



Amazon.com has a very similar scheme as well, and that used to bring in tens to hundreds of dollars a month for me, but I wasn't willing to have any financial ties to a company that sells books that promote child molestation.

Tuesday, October 28, 2003

I Sometimes Wonder If I Just Don't Enjoy Amateur Astronomy Enough



Especially when I see an ad like this one:
am selling my DarkStar 22" f/4.5 Dobsonian telescope. She sets up with absolutely no tools or ladders whatsoever in less than 15 minutes. (Although you will need a ladder for viewing at zenith, as she is 8 foot high at the eyepiece!) Unlike other big dobs, she nests together for just one easy trip from the truck to the field. She comes with high resolution digital setting circles and hardware (bring your own computer), 6' wheel barrel handles, 10" tires, black rip-stop shroud, and a Telrad finder. Pegasus primary and secondary. $6000 US dollars, if using paypal, add the customary 3%. Scope is located halfway between Detroit and Ann Arbor Michigan.



Before I get 100 emails asking, I have found a 30" dob, thus I must sell my baby to fund my further exploration of space.

Friday, October 3, 2003

Part of Why I'm Skeptical of the Claims Against John Lott's Work



It's because his opponents are clearly fierce anti-gun advocates, and not above a few tricks of their own. You read their work outside of the statistical area, and it's clear that the are either not very careful thinkers, or are playing fast and loose. As an example, consider this recent presentation by John J. Donohue III, one of Lott's strongest critics. The paper is ostensibly about the rise of non-discretionary concealed weapon permit laws (what Donohue calls "Right To Carry" or RTC). Donohue points to the recent example of actor Sean Penn, who has a California concealed weapon permit (apparently issued in violation of California law), and how two of his guns were stolen from his car. While Donohue acknowledges that Penn "succeeded in getting one of the relatively few gun permits in the non-RTC state of California," raising this issue as part of a discussion of RTC laws makes no sense at all.



Donohue also points to the now thoroughly discredited Violence Policy Center claim that in Texas, "41 permit holders were arrested for murder or attempted murder...." While admitting that some might have been falsely accused, Donohue never acknowledges that it is routine for Texas district attorneys to charge anyone engaged in a defensive shooting, and that many of these "arrests" never turn into criminal charges, because the grand jury refuses to indict. Donohue makes the claim,
During the first 5 and one-half years of the Texas RTC law, the Violence Policy Center was able to identify that 41 permit holders were arrested for murder or attempted murder (the number would be too low if the researchers didn’t capture every permit holder in their count or if some permit holders committed murder and didn’t get arrested, and would be too high if some were falsely accused). The Violence Policy Center, License to Kill IV (June 2002), http://www.vpc.org/studies/ltk4cont.htm. The current murder rate in the U.S. across all groups is roughly 5 per 100,000, so if one takes 150,000 as the average number of permits over the first five year period, one would expect roughly 7.5 murders per year from gun permit holders (if they killed at the same rate as the average American today), which totals 41 murders over the full period.
There are a number of misleading aspects to this statement. The VPC study claims 41 permit holders "arrested for murder or attempted murder" which Donohue then compares to "41 murders over the full period." Donohue's apples and oranges comparison is either a sign of carelessness, or dishonesty. Which does he want to cop to?



The VPC report also neglects to tell us how many of those murder and attempted murder charges involved guns. Doubtless, a majority, but what relevance would a murder committed with a knife, poison, or a blunt object have to the Texas concealed handgun license? Donohue has to know this. Where's the qualifying explanation?



Donohue acknowledges--parenthetically--that the VPC's number of murders and attempted murders "would be too high if some were falsely accused" but doesn't bother to look at the readily available evidence on this. Examining Texas statistics shows that as of May 17, 1999, there were 22 murder charges filed. Of these, 2 were convicted, and 4 were dismissed. The rest were still pending. Even making the unlikely assumption that every remaining charge would result in a conviction or guilty plea, this still means that VPC's "41" charges are going to be 33 or 34 convictions, and most likely, a good bit less than that. For the year 2001, there was one murder conviction of a licensee, and 157 convictions of non-licensees. This also suggests that the VPC's "41" charges overstates the actual number of murders and attempted murders committed by Texas licensees (unless, of course, 2001 was a very unusual year).



There are other problems with the VPC report that Donohue seems to have missed. The VPC report lists at least two murders that took place on the property of the killer (Jack Reynolds and Daniel Meehan)--where a concealed weapon permit makes no difference whatsoever.



The VPC also lists a kidnapping where no gun was involved, until the victim tried to get away from the kidnapper's home--at which point the kidnapper used a rifle. A license to carry made no difference in this case at all.



Some of the cases that the VPC points to seem to have left no tracks after the arrest. They list a Randy Phil Allen II who was arrested in 1999 for a 1988 murder (which would have been before the Texas RTC law took effect). But whatever happened? There is a Randy Phil Allen II who lives in Texas, but while he responded to my email, he refuses to answer my email inquiry if he is the same Randy Phil Allen II arrested in 1999.



1. It seems a bit hard to believe that this exact match of name is a coincidence.



2. If it is a coincidence, and he is not the guy who was arrested in 1999, why not respond with, "No, I am not the same guy."



3. If this is the same Randy Phil Allen II who was arrested in 1999, he clearly could not have been convicted, or he wouldn't be out of prison already.



If the claim is that John Lott has violated professional standards in how he has presented his information, Donohue is in no position to cast any stones. Using VPC's information, while not discussing its serious shortcomings, is clearly misleading. To quote Donohue:
It is also important for the political and scholarly audiences to be sensitive to signs of over-zealousness on the part of researchers as this may give clues that something more than the search for truth is motivating the research.


Thursday, August 7, 2003

Vatican Set Policy on Secrecy Concerning Sexual Abuse by Priests?

This report from CBS News quotes from a 1962 document written in the Vatican, and claims that the document outlines a strategy for keeping sexual abuse by priests secret, under threat of excommunication from the Catholic Church.
The document, once "stored in the secret archives" of the Vatican, focuses on crimes initiated as part of the confessional relationship and what it calls the "worst crime": sexual assault committed by a priest" or "attempted by him with youths of either sex or with brute animals."

Bishops are instructed to pursue these cases "in the most secretive way...restrained by a perpetual silence...and everyone {including the alleged victim) ...is to observe the strictest secret, which is commonly regarded as a secret of the Holy Office...under the penalty of excommunication."

Larry Drivon, a lawyer who represents alleged victims, said, “This document is significant because it's a blueprint for deception.”

Drivon said the document proves what he has alleged on behalf of victims in priest-abuse lawsuits: that the church engaged in Mafia-style behavior -- racketeering.
Regular readers of my blog will know that I am not impressed with the Catholic Church's behavior in this area; it is something of a toss-up as to which organization has done more damage to children: the North American Man-Boy Love Association, or the Catholic Church's cover-up of child molesting priests. No, I'm not being flippant when I write this. NAMBLA is pure evil, but their numbers are small; the Catholic Church's perpetually pederastic priests seem to be legion (I picked that word "legion" for a reason), and they have been abusing children for at least decades in North America.

Nonetheless, reading this news report, and what it quotes from the 1962 document, I don't see the smoking gun that the report suggests. I can imagine several other contexts for the quoted text that are far less damaging. The Catholic Church should release the entire document in question, immediately, for independent evaluation.

UPDATE: As I said above, it doesn't sound the 1962 document says quite was CBS says it says. Here is an alternative explanation that suggests CBS's problem was a bit more serious than just careless reading.

Saturday, July 12, 2003

Need A #4-40 Thumbscrew



No, not the medieval torture instrument. There is a little set screw that holds eyepieces in place on my telescope. It's about 1/4-1/2 inch long, with a knurled head that makes it easy to tighten down on an eyepiece. A few months back, this little thumbscrew fell in the deep grass in my back yard, and has been MIA ever since. I am using a #4-40 screw as a replacement, but it's not quite as convenient. Unfortunately, local hardware stores don't carry anything quite this small with a knurled ending, or any other sort of easy to turn head on it. If you have one that fits this description sitting around your workshop--or can tell me where to buy one--I would very much appreciate it.

Friday, January 31, 2003

Deleting Bellesiles From Reinhardt's Decision Doesn't Solve the Problem



As several bloggers have pointed out, Michael Bellesiles has been deleted from Judge Reinhardt's Silveira decision. But after reviewing the changes, Judge Reinhardt seems to have done himself in. What the decision said before was:
During the period that the Articles were in effect, both George Washington and Henry Knox, who was to become the nation’s first Secretary of War in the Washington Administration, urged the creation of a standing national military force, to no avail. H. Richard Uviller & William G. Merkel, The Second Amendment in Context: The Case of the Vanishing Predicate, 76 CHI.-KENT L. REV. 403, 411-13 (2000). Washington in particular felt that the need was acute; in 1783 he wrote a document entitled Sentiments On A Peace Establishment, in which he recommended establishing a national militia that would exist along with those maintained by the individual states. Subsequently, he wrote to John Adams in the wake of Shays’s Rebellion that because of the lack of a unified national military force, “[w]e are fast verging to anarchy and confusion!” Letter from George Washington to James Madison (Nov. 5, 1786), in 29 THE WRITINGS OF GEORGE WASHINGTON, 1745-1799, at 51 (John Clement Fitzpatrick ed., 1931) (quoted in Michael A. Bellesiles, The Second Amendment in Action, 76 CHI.-KENT L. REV. 61, 65 (2000)).
All that Reinhardt has done on this footnote is delete
(quoted in Michael A. Bellesiles, The Second Amendment in Action, 76 CHI.-KENT L. REV. 61, 65 (2000)).
Reinhardt hasn't made any other changes, and as I pointed out a few weeks ago, the problem is that the claim "because of the lack of a unified national military force" is not strongly supported by the context of that quote. Before, at least, Reinhardt could at least say, "Well, I was relying on Michael Bellesiles, who made that claim." Now he has deleted Bellesiles, and is asserting that the letter from Washington to Madison makes this claim. As I wrote here,
Now, Washington certainly mentions the Shays's Rebellion in this letter--after discussing "anarchy and confusion!" But there isn't any discussion of "because of the lack of a unified national military force." One might at least as fairly assume that Washington was referring to the problems of finances and the previous inability of Congress to vote for a "paper emission." Washington was definitely a supporter of a standing army, having found militias to be a "week reed" upon which to rely. But this letter is quite a bit more ambiguous than either Bellesiles's representation of it, or Reinhardt's representation of Bellesiles.
Reinhardt can't even blame this on Bellesiles now. He needs to either remove this very questionable claim about why Washington said what he said, or admit that he is making a highly arguable assumption. Of course, this level of intellectual integrity would destroy the rest of Reinhardt's decision--which cites a decision that argues that only weapons of "civilized warfare" are constitutionally protected as proof that military style weapons are not constitutionally protected.