Posts Made By: Tom Hole

Floyd,

I'm not George.

Folks that bought an original 102 got 1/2 off on an accessory of their choosing. If they chose a binoviewer, they got it for $99.

We have to pay $199.

Hopefully get mine soon.

Tom

My situation allows me to have an 11" Starmaster as a quick look scope. I have it on an eq platform that is on wheels. It is always set up in the garage. The time from making the decision to view to actually viewing is usually less than 2 minutes. If I decide to collimate (usually not required) it's 4 minutes. I can go out, look at M42 and Saturn and be back inside in less than 5 minutes. If it's nice, I stay out.

So, I feel I have the ultimate quick look scope: an 11", f/5.4 Starmaster with a rolling eq platform, a nice Catsperch chair and binoviewers. Now if I just had clear, steady skies more than 10 times a year, I would be in heaven.

Tom

Nils,

I would compare the areas in order to compare light gathering.

But don't forget the resolution issue. A 10.6 inch binoscope and a 15 inch binoviewed telescope have the same mirror area, so similar light gathering. But the 15 inch has a much higher resolution than the 10.6 inch binoscope.

I'd want one of each to make sure, though.

Tom

Joe,

Welcome to a most extraordinary world. Keep us informed on all your first impressions as you only get them once.

Tom

Brett,

You can expect some of the most amazing sights you have ever seen! Here is some info on what I have seen through an XT10, 10" dob. I would expect your 8" to come close to this performance, but I will caution you to expect to see less when you are first starting out. As you observe more, you'll see more. But this might give you an idea of what to expect.

http://www.tomhole.com/What%20will%20it%20Look%20Like.htm

There is a link down the page a ways for what you might see on deep sky objects.

http://www.skyrover.net/ds/

This is Jupiter at 305x in a UO ortho:



That's on the page as well.

Tom

I agree and disagree. Just as there is scientific evidence that indicates alcoholism might be a genetic trait passed on by previous alcoholics, there may indeed be a pre-disposition for homosexuality present in the genome.

But, there are alcoholics that don't drink. Granted, there is a difference between the consequenses of alcoholism and the consequences of homosexuality. But the consequences should not dictate the choice (easy to say, hard to practice). One's perception of right and wrong (eeeeeghads, MORALITY) should dictate whether one chooses to drink or not drink, smoke or not smoke, gay or not gay. If your morality allows for homosexuals, then I accept that. My morality does not.

I do believe being gay is a choice. As clear a choice as I make every minute of every day to not light up again. It ain't easy, but doing the right thing can often be a difficult choice.

So, I guess I don't mind if someone chooses to be gay. Just don't expect me to accept your choice. There is always a choice.

Tom

Jim,

I just finished up a test I have been meaning to do for a while. Using my proprietary scientific method, I compared the Orion collimation cap, Orion Cheshire/sight tube combo, Orion standard lasermate, Kendrick 2" laser, barlowed laser, Catseye 2" Black Cat cheshire and Catseye 2" Infinity autocollimator. Oh yeah, I tried out my Mk1-Mod0 eyeball as well. The results kinda surprised me a bit.



I will write up an article for Astromart, but here's a summary:

The best for primary tilt adjustment? Gosh darn it if that cheapo collimating cap that Orion provides didn't work as well as anything. It is precise and accurate. It wasn't so good at the secondary tilt, but good enough, I think (secondary tilt is not nearly as critical as primary tilt). All of the methods were accurate and precise enough that I would use them on my Starmaster. The lasers were prone to wobble, but careful insertion lead to repeatable and accurate results. Proper laser collimation is required.

The best for secondary tilt? The Catseye Infinity autocollimator, but the lasers did almost as well and, IMHO, certainly as well as required. The collimation cap and cheshire were not as accurate, but probably good enough.

The Mk1-Mod0 eyeball was good enough to get you close on the secondary and primary, but not for critical observing. Just too sensitive to eye placement.

What would I get? A cheapo laser for the secondary tilt and an Orion collimating cap for the primary tilt. Or just the collimation cap. Eeeghads! I have over $400 worth of collimation tools and I'm recommending a freebie (Orion doesn't even sell these things seperately). Actually, I recommend that you use whatever you like best. I like the Black Cat for the primary and a laser+autocollimator for the secondary. If you like the cap, feel free to continue its use as it works as well as anything else. If you like high tech lasers, they work, too (make sure they are collimated, themselves). If you like star collimation, well, I dunno about that as it's cloudy and I couldn't try that out.

For those that care about such things, the truth data was the Black Cat and Infinity. I have checked them against myriad star tests and they have proven themselves to be right on.

One note: I have a Catseye red triangle as a center spot for my primary. IMHO, this is a much better type of center spot for accurate collimation. Just easier to see very small deviations. Her's a pic:



Anyway, surprising how well the simple stuff works.

Tom

I would think it would be fairly simple. Put a motor on the azimuth and elevation adjustments. Then in a similar fashion to a Dob Driver II setup, use the keypad to keep an object centered. The computer decides what adjustments to make in the alt/elevation world to cancel out the non-sidereal motion. Or, to keep with a walk then run theme, you very roughly align, center a star, let 5 minutes pass and then recenter the star. The computer adjusts the alt/az motors to account for the error. Do it again for a longer period of time for a more accurate alignment.

I'm a dob guy and know nothing about eq mounts, so I suspect I am not even close on this one. But I'm waiting for my daughter to finish her nightly reading so I can say good night and this is the only interesting thread that I found. Besides the politics forum

Tom

Jim,

Buy this:

http://www.astromart.com/classifieds/details.asp?classified_id=313354

You will own one of the best 12.5" scopes that could possibly be made.

Tom

Don,

Thanks for the data. I'm sure Harry will chime in on what is limiting this measurement to 38mm or so, but in the mean time I'll chime in with my thoughts.

If the 38mm restriction is actually a well placed baffle, then the 45 clear aperture measurement is a valid one for comparison. Since the light cone is in fact, a cone, 45mm at the nose and 38mm further up the chain is not a bad thing. It probably is a good thing as it will reduce stray light. Harry probably won't publish a diagram, but a simple explanation of where the restriction is placed in the light path would be helpful.

As to the surface quality of the beamsplitters, Harry has stated that he shoots for 1/8 wave. I will not condemn that. His choice. Whether one agrees with it or not is made irrelevant by his 60 day money back gurantee. Do a star test on a good night with a single ep (star tests are wicked animals to conduct properly, but they do tell a detailed story). Then compare that to a star test with the 45's and note any changes. If you don't notice a change in a properly interpreted star test, you will most likely not see any difference at all in the ep's.

As an example, my old XT10 had a slight amount (maybe 1/6 wave) of spherical error that was noticable in a star test. I forget if it was under or over correction. When I used my TV binovues, the XT10 star tested better. The spherical error was 1/10 wave or better. The star test with the binoviewers looked noticably better than the one without. So, if you want to know, just do a star test. If it looks good, I wouldn't worry too much about the wave error on any of Harry's optics. If it looks bad, you can send it back. As hard as I am on Harry, it's tough to argue with a money back guarantee. Just wish he'd stop with the patronizing. Mildly irritating.

Tom