Posts Made By: Greg Nowell

Roland's recent post on eyepiece lateral color and atmospheric refraction as sources of color that apo enthusiasts sometimes wrongly attribute to their scopes reminded me of another exchange I had with him some time ago.

We were discussing in some forum the red/blue refraction effect on Jupiter, which actually is visible at *quite high* altitudes from the horizon, and I said something like: "Well I don't get it. If this is due to the atmosphere and not the optics how come we don't see it on the moon?"

Roland said: "It is on the moon! You just never noticed it!"

Ever since that exchange, I see the red/blue refraction on the moon, naked eye, ALL THE TIME. It reminds me of when a film expert girlfriend of mine told me, maybe thirty years ago, about the black dots.

"What black dots?"
"Most people don't notice them."
"What do you mean?"
"In the upper right corner. When you get to the end of a reel, there are these black dots that appear to tell the projectionist to get ready to start the new reel."
"What?!"
"You'll see."

And then I saw the black dots all the time. Jeanne ruined the movies, and Roland ruined the moon.

That's the way I see it.

Greg N

p.s. I would find it frustrating to be an apo maker, even if I knew how to go about it. Imagine scouring world markets for the best glass, lovingly grinding perfect curves, and bringing things to high perfection. Some guy drops in a $75 wide field and says "Hey look this thing's got color!" And to tell the truth, the $300 and $500 eyepieces often have some color too. GN

I'm wondering whether our engineer type members are willing to pull out a pencil and envelope to do a rough calculation. Assume you are about 6 feet tall and have to hold a C14 at shoulder height to load it into a GEM, with your arms extended roughly 80% of maximum distance.

How much stress would be removed by raising your height 12 inches on a stool?

I guess it's not purely engineering. Different muscle groups might be brought into play with the tube held lower. It seems to be that holding 40 lbs at shoulder height is more stressful than holding it at the height of the stomach or even lower. But I'm not quite sure how all that works out.

Greg N

I have verified that my 1968 Optical Craftsmen is tracking and was thinking of taking it out tomorrow night, but I'm thinking this is not a good idea. First off, someone commented on Cloudy Nights that on his old Cave in upstate NY, winter adjustments were necessary. Second, I have read that the Syncrhonous pole clock motors (what I have) are very low torque, so if the cold should make the clutches "more sticky" and at the same time cause binding in the gears, it's not inconceivable that I could burn out the motor and have a replacement issue.

Any thoughts?

regards
Greg N

We had a thread a while ago about the OMI mirror I bought here. I had it out for first light the other night and it is performing very well. Since the seeing was mediocre I can't say that the mirror is excellent but it shows no obvious issues. After using the 10" f/6 for over six hours I can say that it certainly falls within the good-to-excellent category, but it takes many nights to reach an opinion as to where it falls within that range. At 217x I was able to make out some faint markings near the Meridian on Mars, they came and went with the seeing, so combined with other performance factors I'm a happy camper. We had a discussion here about the validity of OMI's test reports and whatever one might say about that it would appear that my report data was more accurate than not. This is a good scope, might even be a great scope. I don't regularly follow Mars but I found a picture on the net (not a very great picture but in a sense that helps, makes it more realistic) which shows the features that I think I saw near the Martian meridian. I'm uploading it with my comments.

The polar caps and dark rings around the N & S were very easy to see.

Newts are Nutz: When I first trained the scope on Saturn I saw a double image and so did the other two Newt owners present. I couldn't believe it and had a fainting heart sensation of having gotten another dawg mirror. But this is my first Newt of any size. My friend Bernie reached over and said: "What's this thing?" and removed the dustcap from the rear end of the Newt.

Now this end cap is cloth and very easily lets air through: you can breathe right through it. But the *instant* Bernie removed that end cap the double image went away and the optics became very good indeed. I can't figure it out. Everyone talks about tube currents and all that. But I use an SCT with a "permanent end cap" and I have NEVER seen as bad an image in the C14 as I saw in this Newt with a cloth cover on one end and open to the night air (6* F) on the other. So impressionistically I think that whatever is going on with tube currents, for some reason, it is much worse in Newts than SCTs.

We looked at a lot of stuff but my favorite was M81/M82/NGC 3077. I've looked at these in a number of scopes, some bigger, and some smaller, such as my 4 and 5" refractors. I've never had such a good view. The ten inch is much brighter than my refractors and with its two degree field it seems to frame these objects perfectly. I've also seen them in 14 and 15" big fast Newts but they seem to put more black space between the objects, the framing isn't as good. So 10" f/6 is a sweet spot for this particular object. I've had good views of these objects in my C14 but always individually.

Because the original primary on this 1968 scope was irretrievably bad, and it now has an OMI, it is not really an Optical Crapsmen any longer. It is a synthesis of old and new. So I'm happy to have it with a Moonlite focuser and I'm looking forward to mounting it on my AP900QMD.

regards
Greg N

Saturn is no longer a ball with a popsicle stick through it. Last night it was showing well in my FS128 and my friend's 8" Dob at powers ranging from 170x to 300x. The view was very good in the 4mm ZAO II but I switched to the XW5 because I had to run the hair dryer continuously to keep the ZAO II from fogging. This was true even if I kept my eye at some remove from the eyepiece. The seeing was very good and the banding was showing well.

Mars was also about as good as I've seen it, and better than the frustrating 03 opposition. Clearly if one has to pick between size in arc seconds and altitude in sky (and hence better seeing), sky altitude wins. The Syrtis Major and Sinus Merdiani features were showing very well with much fine detail. The FS128 did a fine job but the killer 8" f/8 Newt showed on average a better view.

Temperatures dropped to about 10F and then rose to 12F by evening's end.

Greg N

My ad is here...

http://www.astromart.com/classifieds/details.asp?classified_id=671512

The associated video is going viral! I'm famous!

Greg N

I'm a guy who has contributed $ (more than the non-contributors, but not nearly as much as some people around here) and some articles (which I think contribute to the quality of the site--articles in general anyway, I leave my own contributions to the judgment of the public).

Let me share some thoughts. I teach at a university and some years ago, tired of having about a 40 to 50% absenteeism rate, implemented some tough attendance rules wherein high absenteeism led to lower grades and even fails. My teacher evaluations plummeted during this period. (Incidentally, in most public universities, about 40 to 50% of the undergraduates never get a degree. There's an obvious correlation, and my absenteeism is no worse or better than most other courses offered by other instructors.)

What the students "got" out of my attendance tirades at the beginning of the semester was that I was in a kind of war-of-judgment against them and that I resented them. They resented me back. Not all students resented me, but enough to affect my popularity numbers in end-of-the-semester survey sheets. In fact some students applauded the policies because they felt non-attendance dragged down the quality of their own experience. So this situation is very similar to what is going on here, except that we're talking small contributions instead of attendance.

Then I went to a group that counsels teachers on campus how to improve their pedagogy and I was advised to substitute very rapid no-make-up quizzes for attendance. I gave up ranting about attendance and just said there would be quizzes once a week. They were fairly easy and quick to grade, and at the end of the semester I had a good participation metric. I didn't have to lecture the students and my popularity numbers went up.

Incidentally, not being "at war with my students who were blowing off the rules" made me feel better too. I was more relaxed about the entire class room operation and ceased to focus on trying to squeeze something out those who simply weren't going to put out, and were in fact quite self-righteous about their right not to.

But in the end I got a system which gives me an attendance metric and the students got an instructor who was not lecturing them about attendance. So here's the question I put to you all: how can you do something similar?

Because we need to break this down one step at a time. First of all, it is to the advantage of the committed members who contribute to the site to have all the ones who are, in the context of donations, considered non-payers. That's because we as sellers want the largest possible number of "certified" buyers. It is in our interest to have this place be reputed to be *the* friendly, safe place to come to buy and sell. (This objective is not being met as well as one might hope.) We have to remember:

Feeloaders contribute by providing numbers
By providing word of mouth
By occasionally getting more involved and becoming contributors
By occasionally buying
by occasionally selling

So, in this sense, the objection voiced by non-payers that they should be allowed to "feel good about themselves" is pretty much the same as my students who didn't want to come to class but didn't want me lecturing them about attendance. When you get into that situation, it's a conflict that cannot be won. When one puts out resentment one gets resentment back, never mind who's right. It's that simple. The strategy is not good business (and not good pedagogy).

I would suggest that Astromart management consider what it is that is the sorest source of grievance: namely, high volume advertisers who don't contribute. Since new members now have to give credit card information, it would be fairly easy to arrange the TOS to exact a fee when certain thresholds are passed. Thirty ads per year (or whatever, I won't set the policy) with a standard one time joining fee for example is a generous allotment that gives the vast hoi polloi the chance to get their feet wet in selling and draws people here so that the higher volume sellers have a market. That's a good thing, right? If management feels that someone who has had 200 ads and made no contribution is gaming the system, then management should have a rule: if you reach the 100 or 200 ad threshold and don't contribute, you automatically get charged some amount.

If the person has paid some amount before reaching that threshold--even if it is small--then the person does not get charged the threshold amount. I envision providing people with an automated notice, sent to their registered account and also to their Amart mail facility, that they were nearing the threshold where they would be charged if they did not make a voluntary contribution.

So you could have TOS which gets some money out of high volume users and you could also run an operation where many people would be operating at very small, almost free costs and that is good for building up the size of the buyer base which is in everyone's interest.

I am basing my suggestion here on the observation that most of the negative energy is directed at the many non-contributors who have made many dozens or even hundreds of ads. The solution is to find terms of service which allows the people managing the operation to feel comfortable that the system is not being exploited, and that, like many other operations of this kind, the low volume participants get a good deal for free (or for $12) while others get tapped on the shoulder and told it's time to pay in. Not all ads on Craigs' list are free, I'm told. If management feels comfortable with the business model it won't fall into the trap of criticizing the customer base which is absolutely a no-win situation.

Incidentally, I'd like to remind Astromart that some users will post an ad, delete it, re-post (maybe because they've got pics and want to start at the "top of the line"), or re-post because they are lowering their price. These people will think that they are "running one ad," which to astromart may look like three.

Certainly there is something that could be done about this: have a lifetime count of ads posted and ads deleted either in the membership display option (for everyone to see) or displayed privately to the member (on the left in the "my account" section). It could be accompanied by a "free ads remaining" indicator which would make it plain when a user was coming up on the threshold to either voluntarily contribute or get charged.

In other words, it should be possible to set up a system which meets the goals of large membership and making sure significant users kick in. And then when this is done one need not ever criticize individuals for not contributing again, one understands the system one has designed, and lets it operate. (I didn't mention attendance at all last semester: it's not because my feelings about absenteeism changed, it's because I decided to "accept what is" in dealing with large numbers of people). This will improve the tenor of the operation, achieve the goal of generating some revenue, and allow attention to turn to other things. The Astromart ads which ask for donations could make their pitch and also have a reminder that high volume users will be charged if they don't make some kind of contribution (and I'm thinking yeah you could let someone get away with a $10 or 15 individual donation or 5 pack purchase to escape a $25 charge, for example).

Anyhow that's the way I see it. Obviously it's not my business to run but I do think there are some parallels with my own "business." I talked over my situation once with a student who as a lieutenant in the Army and asked, "How the hell do you teach people to take their rifles apart and put them together again and pay attention?" He pointed out that he had options that I don't: curtailing weekend passes, give me 50 push ups, run a mile, etc., and that even then, those don't work all the time, which is why they invented the dishonorable discharge (and Army prison). He pointed out that I can't do those things and would just have to organize my operation accordingly. In this I think my situation and Astromart's have some similarities. I think it is possible to set up a participation structure that is part cheap and free and part voluntary--organizations like the Sierra club do it, they have dues, they also let people come on hikes without being members, even lots of hikes, which is interesting, because they have substantial insurance costs associated with their organized activities. And then there are also lifetime members and sustaining members and all of that. Astromart is not alone with this issue.

regards
Greg N

As a general rule, my Vixen ED102 f/6.5 rides my C14 to provide wide fields. I have occasionally seen it do other things that gave me pause. For example when watching a moon emerge from behind Jupiter on a night of poor seeing, the refractor seemed to do a better job of giving good definition between the moon and Jove right at the limb.

So I have gradually come to think that small scopes can indeed outperform big ones in bad seeing conditions.

But last Friday night The C14 trounced the 102mm on splitting Rigel. The seeing was poor. The refractor just wouldn't show the dim companion. I'm trying to figure out why. Maybe in bad seeing the dim companion star image gets smushed that the effective surface brightness of the seeing disk is diminished, enough that the small aperture can't pick it up? Maybe the brightness of Rigel would also diminish the contrast.

Anyhow the C14 showed a clean split. The C14 as a rule does pretty well with doubles, though I don't go double hunting often enough to have bagged any sub arc second specials. Izar was virtually unsplittable later that night by either scope. On Rigel I pushed the refractor through a variety of magnifications from 40x to 180x.

Both scopes were thermally equilibrated obviously the C14 takes longer to cool than a 4" doublet.

Thanks for any insights,

Greg

I've kicked in money to AM here and there but damned if I can remember. I think I was a purple supporter once and I think I paid for an ad to be highlighted once or twice. When I found the 5 pack ads it seemed to me to be the ticket that I liked, in comparison to a month's support the ads are there when you need them.

So to be brief do the 5 packs count as support?

thanks
Greg N

p.s. I'm glad I found this thread I'll try to let some of my laggard friends know what's up.

I just got this back from OMI. I know a few pinholes are inevitable but I thought I would ask folks what they think....