Posts Made By: Jon Isaacs

Hi:

Just a heads up.

Mercury is currently rising about 90 minutes before the sun so right now is a good time to see Mercury. Mercury is a fast mover but it should be visable for the next two weeks.

Mercury is one of my favorites, there is no surface detail to see but the phase is apparent if the seeing is at all reasonable. Right now it is about 60% illuminated and that will be increasing.

I remember reading once that only a few percent of population has ever seen Mercury, it is visable both with a scope or naked eye even...

Jon

HiL

Look for a bit of info here.

1. I have recently acquired a couple of the older sonotube Celestron Starhoppers, one is a 6 inch, the other is an 8 inch. I like the way the trunion bearings are mounted, big aluminum dovetails that allow quick adjustment of the balance.

I had seen these back when and have heard rumours they were made by Discovery but both have a quite unique mirror and mirror cell. The mirror has a curved/spherical back and the mirrors mount with a single bolt in the center...

Anybody know the story/history on these mirrors?

Mostly just interested as they are someone different.

2. Also, the OTA's are about 52 inches long and that's about 4 inches longer than fits in my car and about 4 inches longer than they need to be. I am considering cutting the tube on the 8 incher, any suggestions on how to make a nice clean cut in SonoTube?

Thanks

jon

OK, so you saw the game against ND...

What do you think?? Assuming the beat UCLA, should they be in the game for the title??

If there were no BCS then Ohio State would have the clear shot at the title without playing a team like USC. Well, I guess I have to take that back because were there no BCS, the winner of the Pac10 would be playing the winner of the Big10 so it would be the same game but played a bit further west in the Rose Bowl..

Being from the Southern California area, USC is about the only team one an root for so over the years I have been a USC fan.

I thought USC has looked better than anyone else with a shot at the title and their defense is pretty decent.

Should be a good game if that is how it turns out.

Jon

Hi Folks...

So finally the story of my Burgess Optical 102/F6 has ended. As most of you know, there were many ups and downs with this scope and finally more than 2 years after the promised delivery date, I was able to secure an Orion 100mm F/6 Objective resulting in the "Burion 100mm/F6."

This surgery transformed the telescope into something I had many good times with, it was a good performer and provided the sort of views one could expect from a decent achromat. I could split doubles nicely, delta cygni was possible with the new objective whereas Castor was not with the original.

And to Burgess's credit, when they quietly announced that the "semi-APO" objective was not going to be produced, they also quietly refunded my credit card, something I only noticed accidentally. As a result, I felt that in the end this telescope should end up in some special place where it would do some good.

This fall I spent some unbelieveable nights on the Navajo Reservation and carefully compared the Burion with the ED-80. The result was that I knew the Burion needed to find a new home.

Fast forward to an Astromart ad looking for 6 inch DOB parts to go to Uganda to replace a 60mm refractor being used for teaching. As I had/have a C-102HD that I had bought for a song, I offered it to this worthy cause. This was to be mounted on a Vixen Polaris mount that I had been given via Craigslist. This seemed attractive and a deal was struck.

However when I began packing the C-102 HD, I realized that the Burion with it's nice case and shorter focal length would be a much better choice. The necessary parties were consulted and it was decided that indeed, there would be a Burion in Uganda...

So, right now somewhere out in the backroads of Africa is a Burion 100/6 along with a Polaris mount, a BW-Optik 30mm 80 degree and a selection of 1.25 inch eyepieces.

I do miss the scope but it is good to think of that after its troubled lift off that it now doing its most important work.

(The photo is of a friend with the Burion + Polaris as we check it out prior to shipping it.)

Best wishes to all...

Jon Isaacs

>>Sometimes I think the obsessive placement on scopes of warning stickers about the sun is equivalent to haveing a warning on the driver's side of the car, "Don't Drive into a Brick Wall. Severe damage may occur."
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I have a hard time seeing the placement of one relatively small sticker as being "obsessive." It is probably there as a result of a law suit.

I would put in the same class with "Smoking Cigarettes may be Hazardous to Your Health".

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Not looking at the sun with a telescope without an appropriate filter is a good topic to discuss here as this is the beginners forum.

Older telescopes often came with a solar filter that attached to the eyepiece. These are considered dangerous as they work by absorption and can heat and a break.

Right filter for viewing the sun is a reflective filter that fits over the objective. These are available from a number of vendors to fit a variety of scopes. They start at about $30 and go up from there.

jon

Jon

I was looking into swapping the rack and pinion focuser from my Orion 120mm achromat for a Crayford type from one of their 100mm ED models. When I checked with Orion tech support the person I spoke with cast doubt upon whether they were interchangeable. This was surprizing since Moonlite seems to offer just one aftermarket focuser that fits most Synta refractors. Has anyone tried this and what success did you have?

Thanks, Mike
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I think it depends upon the diameter of the OTA. The ED-80, the ED-100 and the AstroView 100mmF/6 all use the same tube rings and the same tube diameter. I believe the focusers will interchange.

But the 120 has a larger tube and IMMSMW, the 120mm focuser is larger in diameter.

My guess is that Moonlite offers adapters for the larger scopes.

jon

Hi:

In an effort to look to the future and think in a positive light about BO, I had the idea that there are some scopes like the 80mm F/11 Planetary hunter that might be good products for a small vendor, filling an otherwise unused niche.

I would hope the rest of you would add your ideas on stuff you would like to see made.

Here's one that would seem to be a good bet to me:

80mm F/11s have long been popular but these days a good quality one is quite uncommon. The PH seems to be an remake of a classic while moving it into the 21st century with nice features like a 2 speed focuser.

Last night while observing with my RV-6, it occurred to me that building a simple but high quality and modernize 6 inch F/8 Newtonian could be a real winner.

6 inch F/8 Newtonians have long been considered APO killers, last night the views were just spectacular in my RV-6. THe seeing was poor but M35-M38 were as good as I have ever seen, pinpoint stars edge to edge with 4 element eyepiecs and bright and sharp. When the seeing is good, this little wonder seems to work miracles. Double stars and planets, it pulls its weight.

With nearly a half a degree of coma free view, a 6 inch F/8 doesn't need a corrector like a Newt-MAK to get the good views, it is the ultimate in simplicity...

As far as I know, currently there is no one selling 6 inch F/8 Newtonians in the US, with a low profile focuser and a small CO and a nice Pyrex or even quartz mirror, this could provide BO with a scope that is unique and yet highly capable so that rather than competing head to head in a very competitive market (small refractors), they would be expanding the market place and providing the community with a scope in the classic tradition that was the standard not many years ago.

Jon

>>And I should add, I've been told that the coolpix compresses data for storage, so information could be lost there, and it may just be that I have insufficient control of how the camera reacts to the intense light of the fully illuminated portion of the moon.

regards
Greg N
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I think this is important because there can be significant data lost. Which Coolpix do you have??

Have you tried hand holding single shot??

With my CP 4500, that is works best for me.

jon

>>>Terrific images!!! Problem is that all illustrations I see of achromatic doublets show the setup as it was originally in the scope and not as I presently have it. Am I smoking something, or does this make sense? Any thoughts? Thanks, Mike.
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Mike:

It doesn't make any sense (actually it probably does) so I think you should immediately return the objective to how it "should be", the great views it now provides be damned... 8O 8O

Jon

Hi:

I just picked up a used PST and would appreciate any tips on getting the most out of it. What can you see with it in the way of surface detail, what eyepieces (focal length), adjusting the filter, any and all tips appreciated.

Jon