Posts Made By: James C Chandler Jr

The most embarrasing line of the night may have been: [paraphrased] "All I get are the hard problems. If they were easy someone else would have solved them and I wouldn't have to."

Perhaps it is over-admiration of humility, but if I'd accidentally been that egotistical in public, might be ashamed to go in public for a long time. Made me cringe.

It is said that protein folding is a pretty tough problem. Maybe if O can find a few free minutes away from that tough problem of inventing the fastest way to spend the grandchildren's money, maybe he could solve that pesky protein folding problem.

The ammo shortage may be growing more intense. One would have thought that all shooters in the country would have plenty of ammo by now .

Perhaps 'hard core' hobby shooters started buying around the election, and as things have progressed more folks have entered the ammo hunt?

Something which may be shifting it into a higher gear-- Recently there have been national news items on this phenomenon. Maybe the national news coverage has alerted every guy with a rusty'n'dusty old gun in the closet, that he should go buy ammo?

Stock seems shipping, but doesn't stay on shelves. The local Sportsman's Warehouse at one time kept big shelves of ammo. And big stacks of reloading machines in their cardboard boxes. I've been going by about weekly for awhile, and there is hardly anything on the shelves. Whatever rifle ammo they still have must be for very rare guns . Today I didn't even see any reloading machines in-stock though there are a few dies still available. Shotgun shells are the only thing S W still has in copious stock.

Primers, bullets, and powder is practically non-existent. Stock does come in, because one day they were out of small pistol mag primers, but a week later there was a lonely box of 1000 small pistol mag primers available to buy. They were out of Blue Dot powder awhile, but one day they had a lonely pound of Blue Dot on the shelf, but no longer after I bought it . I have a couple of pounds of W231, but have been looking for another pound for awhile. I don't like to mail-order primers or powder, because the hazardous materials shipping fees make it too expensive.

Bricks of cheap .22 LR seem nonexistent. Wallyworld usually has big stacks of .22LR bricks, and they only have a few lonely 50 bullet boxes. They had a few boxes of .223 Rem in stock.

At Cabelas, MidwayUSA, and Sportsmans Guide websites, the only .22 LR is the really expensive target stuff. There are a few lonely boxes of 9mm, .357 mag, and .223 Rem at the mailorder websites.

Perhaps the most puzzling shortage is the complete absence of ANY kind of .380 ACP just about anywhere. You can't even buy crappy East European steel-case FMJ .380 ACP. I didn't realize that .380 is such a popular round. Perhaps everybody and his brother has a little cheap rusty .380 pistol in the bedroom drawer?

The feller who owns a small local gunshop-- He has about any caliber ammo in modest quantities. Maybe most folks don't even know his store exists. Or it might be his prices. He doesn't exactly give his ammo away . Or maybe the guy has made enough industry friends over many years that ammo manufacturers will ship a few cases to him in preference to Walmart or Sportsmans Guide? Dunno.

I don't get out much, but talking to the gunshop dude-- He's an old army sharpshooter who was still doing contract army marksmanship training a few years ago. Dunno if he still does that. There is a city detective who is there on saturdays, nice guy who runs the feller's handgun carry classes. They were shooting the bull. Gunshop owner said everybody and their sister is signing up for handgun carry classes and buying guns. He said many common folks are very scared about the economic and political situation. The detective said that fellow cops could be heard reading juicy quotes aloud from the Federalist Papers in the police break room.

Strange times. Ain't trying to exaggerate what is probably a minor transient fad like the Y2K semi-panic, but this seems slightly unusual.

I think the heavy-handed interference with bailed-out companies is probably long-term good, because it will become a poison pill for future companies coming anywhere close to accepting future bailouts.

If these rules had been delineated from the get-go, it would have saved us hundreds of $billions, because the poison pill would have kept most companies from initially accepting any money.

IOW, the heavy-handed interference will hopefully backfire and make most industries 'meddle-proof' in the future.

Update: I disassembled the HF digital caliper a second time and cleaned the sensor with a dry microfiber cloth (the minimal manual instructions had recommended compressed air so that is what I used the first time).

The sensor is just a tiny circuit board with an array of parallel copper stripes. It could get scratched if abused sufficiently, but does not look terribly delicate.

This got the HF digital caliper to agree with my old micrometer to within 0.0015" to 0.002" (the half-thousandths indicator on the digital caliper isn't real repeatable). This matches the >200 mm absolute accuracy spec in the one-page manual, though I'm measuring distances < 25 mm and the spec sheet does not indicate whether to expect better accuracy at short distances.

Perhaps it is now operating within spec, and for many things a missed 1 or 2 thousands isn't bad as long as it reads the same every time. Perhaps this is remarkable that such an inexpensive gadget could be absolute accurate within a couple of thousandths, and so remarkably repeatable.

But the questions remain about possible 'affordable' alternatives that have absolute accuracy at least to 0.001". The old cheap micrometer is marked in thoursandths, but is easy to guestimate in-between markings, so it seems accurate at least to 0.00025. Maybe 0.001 is asking too much in a caliper? What about in a 4" cheap micrometer?

Thanks again.

Hi Matthew

Can you get focus with a 1.25" diagonal and 1.25" eyepieces?

The focal plane of the 2" EP's I have (not many) appear to be near the field stop, which is near the shoulder of the EP's. If you are truly lacking in-travel straight-thru without any kind of diagonal, then it seems unlikely that 1.25" eyepieces with a diagonal could ever reach focus, as that would move the EP focal plane back another couple of inches at least?

Am not competent to be a mr-know-it-all on the matter. It is just an ignorant observation. Please take my comments with many grains of salt.

1. Is there any chance the previous owner upgraded with a nicer replacement focuser which accidentally happens to be a lot longer than the factory focuser?

From viewing pictures of your guy, I think the factory focuser on your C102 500mm typically looks about the same as the factory focuser on my C102 650mm-- A cast-aluminum cone shape with a rack'n'pinion focus mechanism.

If you happen to have some other shape focuser on your scope, a Crayford or whatever, then perhaps the focuser has been swapped out with something a little too long? That would not necessarily be a bad thing, except for adjusting for the length change.

2. I've been very happy with my C102 650mm FL for the money. Mine was straight out of the new box with no mods. It came with the 2" rack'n'pinion focuser and a 1.25" not-too-bad mirror diagonal and a couple of basic eyepieces.

My C102 would bring all my 1.25" eyepieces to focus with the 1.25" diagonal, but had ordered a 2" dielectric diagonal along with the scope. The 2" diagonal added another inch or two to the light path, and there were several 1.25" and 2" EP's that had insufficient in-focus with the 2" diagonal. I griped quite awhile that for whatever reason they put a 2" focuser on that thing, but cut the tube about an inch too long to play well with a 2" diagonal.

A lot of folks, with various brands of refractors, will decide to shorten the tube for one reason or t'other, but I wasn't wild about the idea of hacksawing a brand-new scope. Am too inclined to tinker, and wanted to put a crayford focuser on the C102 anyway.

Rather than buy the factory crayford adapter for that model scope (which would only duplicate the too-long factory focuser position and require cutting the tube anyway), I made a little aluminum adapter dimensioned to move the new crayford about 1" closer to the objective. I did some careful measuring of what in-focus would be required on all the EP's before deciding the ideal length of the new adapter.

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Anyway, my experience proves that it isn't impossible for Celestron to make the tubes a slightly-wrong length. But in my case, all of my EP's would have easy-focused without any diagonal at all, unless for some EP's there may have not been sufficient OUT TRAVEL without a diagonal (though the factory focuser has a long throw, and there probably would have been sufficient out-travel). I was only an inch or two long in the special case of a 2" diagonal.

You would want to make CERTAIN of your problem, and how much to remove, before taking a hacksaw to your scope, but it isn't that onerous a job.

Hi Denise and Dom

I'm not much a backpacker, but would something like a Stelllervue finder, aka SparrowHawk, at 50mm... Would that be rugged enough and gather enough light for your purposes? One of those little scopes might arguably be smaller than full-size binocs, assuming the selected tripod isn't too bulky in a pack?

I don't think it is waterproof, nitrogen purged, any of that good stuff.

http://www.stellarvue.com/f50.html

It is baffling how this kind of thing couldn't be avoided with a couple of ship-board 50 cal machine guns, circa WW I technology? Perhaps operated by blackwater contractors if sailors can't be trusted to do the job?

Hi Jon.

I read reviews that the 14mm may be the weakest slot in the 5000 lineup. Have seen very good reviews of others in the 5000 UWA line. Am very happy with the 18mm 5000 UWA, and wouldn't be surprised if I turned out happy with a 14mm 5000, dunno.

One review mentioned more reflections and slight coating imperfections in the 14mm, compared with another EP at twice the price. Dunno if my tastes are sufficiently refined to be offended. Maybe.

Dunno about the 14mm, but the 18mm works great in an F3.75 refractor-- Focused sharp across the field. Works equally great in F4, F5, F6.5 refractors, and F10 SCT. Eye relief is fine.

Maybe the 14mm is a lot worse, dunno.

Hi Paulo

I don't have experience with either of those EP's, but wonder-- If 27mm is 'long enough', would a Pan 24 be unacceptably short?

Pan 27 and Pan 24 are awfully close to the same F.L., and the 1.25" Pan 24 might be more 'adaptable' in more scopes and situations, present and future? Also it is a little less expensive, not much.

Am sure Pan 27 is great, and I really like my Pan 24. There are places I use the Pan 24 in little refractors that don't have 2" focusers. If I had a Pan 27 there are more situations it couldn't get used.

Talkin about wide-field, the Pan 24 gives point-focused wall-to-wall stars at > 5 degree FOV (6.4mm exit pupil) in the SV F80 Finder. Pan 24 gives equal great performance at ~8 degrees FOV (6 mm exit pupil) in a 'hot-rodded' 50mm finder. Now thats-a wide field, but 2" eyepieces will not fit the 1.25" helical focusers .

About any battery can explode, notably if shorted or punctured/otherwise mechanically damaged.

Many products' safety warnings are lawyer boilerplate that gets included even in some applications where it makes no sense. Such as instructions to drain the gasoline from an electric chainsaw, or a warning to unplug the power cord from a battery-powered drill .

Many if not most computer UPS, battery packs, and other lead acid devices meant for optional indoor use, are SLA-- Sealed Lead Acid battery. They will explode if you short them and if there isn't a fuse built in there to save you, but they do not ordinarily vent hydrogen. Unless they are broken.

AGM (glass matt) and Gel are two common kinds of sealed lead acid battery. The only time you would have hydrogen venting is if the little pressure-relief valve goes bad, or if the battery gets damaged, or gets real hot from over-discharge or over-current charging. That is the main reason the little valve is there, to handle unfortunate overheating.

You could carefully open your power station and read the text on the battery. If it says AGM or GEL or SLA or words to that effect, it is ordinarily safe to use in the house unless something goes very bad wrong with it.

If it is not a sealed type, you can expect it to vent under heavy use, and I would not use a non-sealed battery in a closed-up house. Only in a very well-ventilated 'semi open' area.