Posts Made By: Thomas Holst

I bought a small, cheap 350 watt inverter (12v/110v) at WalMart for about $40. I just lift the hood on my Ford F150 pickup, set the inverter on a towel on the radiator and use the supplied short cables & clamps to connect it directly my pickup's battery. I then run a standard 20' extension cord from the inverter back to my pickup's tailgate where I place my laptop. I sometimes power a 7 watt/110v red lamp, clamped to the tailgate support, from the same power source. This easily powers my laptop and lamp all night long with no ill effects on the battery. Been using it for 5 years now.

Note 1. I don't believe powering a laptop with a cigarette lighter type inverter is a good idea. You get a voltage drop between the battery and cig. lighter socket, the electrical connection isn't very secure, it wasn't designed for long term use and tends to overheat, possibly blowing a fuse. Connecting the inverter directly to the vehicle battery eliminates these problems.

Note 2. The inverter I use is rated for 350 watts continuous and 700 watt peak power. It is thermally protected, fused, has a built in cooling fan, green power-on LED, a red overload/low battery warning LED, two 3-prong 110v receptacles, and an on/off rocker switch. It has a footprint about the size of a DVD box and stands about 2.5" tall. The power capacity and built in safety features help avoid potential problems.

A while back my wife made me a custom dark cloth for use with a 4x5 view camera to enable me to focus the dim groundglass image in daylight. I just told her what it had to do and she went to a local Jo-Ann fabric store and found just the right thing. It's amazing the stuff they have there.

You might take a look at the stretchy denim type material commonly used for women's jeans or maybe a thinner stretchy spandex type material.

Bob Young said:

Has anyone retrofitted their Televue focuser with one of these FeatherTouch units?

I've installed two of them on my scopes. After seeing what TeleVue's Focus Mate looked like, I put myself on the waiting list for the first TVRFB's to be delivered. My first TVRFB went on my old TeleVue Genesis SDF (see attached photo) and it worked great, so I kept an eye out for a used one and grabbed the first one I saw on A-mart (another TVRFB) and installed it on my TV76. I considered putting one on my Pronto but since I only use it for Solar viewing, I saw no need.

Was wondering if it performed to expectations and how difficult it was to install.

They both perform flawlessly. The TVRF(B) have a 10:1 fine focus as opposed to the Focus Mate's 6:1 ratio. It takes a little careful adjustment to get them just right but it's not difficult. Some words of warning:

1. The original TV pinion block screws will be TIGHT. Also, the screw head sockets will be filled with black paint which must be scraped out first to ensure a good Allen wrench fit. To remove them, use a good quality US made Allen wrench of the proper size and grind the end of it flat to give a full depth hex shape which will bite into the screw head.

2. Upon removing the original TV pinion block and pinion shaft, DO NOT pull the focuser draw tube out of the focuser housing - you will never get it back in right. (This is a warning from David Nagler himself.)

3. Follow the TVRFB instructions carefully and you should have no problems. Installation took me about 45 minutes, being slow and careful.

How does it compare to the full FT focuser?

Dunno, never had one.

At $220 to $250 they seem a little pricey for what you get, but an easy bolt on upgrade beats replacing the whole focuser.

When you see and feel the quality of the TVRFB, you will know you got your money's worth. Also, I like the version with the brake screw as it enables you to vary the tension of the focuser easily for just the right feel.

Michael Koons said:

...but this mess is like turning a battleship, it takes some time, and a wide berth, trouble is, we've got to keep the boiler room turning the screws in the meantime.

I think we already done hit the iceberg, water is flooding the engine room, and there are no other ships within a thousand miles of us.

He's not dead, just busy watching CNN.

Jerry,

With the price of ammo going nuts lately, I can sympathise with you on the cost involved each time you pull the trigger. I too have been searching for the least expensive ammo for plinking and target practice, but I have made a personal commitment to shooting only USA made ammo. When I pick up a box of .45 ACP or .45 Long Colt ammo in a store, the first thing I look for is its origin. (Yes, I'm typing this on my Chinese made computer, but I didn't have any other option and I wince every time I turn the dang thing on.)

Today I finally took the last option for reducing the cost of recreational shooting and started reloading (again). Since I sold off all my good reloading gear 25 years ago, I had to start from scratch, but I think it will be worth it. Not only can I shoot cheaper, but I can taylor my ammunition for better accuracy and my own shooting habits; all made with USA components on USA made equipment. It's also kinda fun too.

Great shot, Alex. We switched my astro club's star party from Saturday to Friday because of weather and managed to get some nice views of the comet; first through my binoc's and then through a friends 16" dob. That is one bright, [COLOR="Lime"]green[/COLOR] comet!

Robert Howe said:

...Is this a satellite that rotated into a reflecting position during my exposure?

To me it looks like either a light fixture or a UFO.

What does it mean that the stars that I smeared by touching the shutter button are in the same general shape as the object?

I don't think they are smeared stars from your handling the camera because they mirror the shape of the brightest parts of the mystery object. They look more like two different types of internal reflections coming from inside the scope/camera. The group of faint images encircling the main image appear to be caused by some type of coaxial reflection, possibly from light baffles, the inside of the focuser draw tube or camera throat. The fuzzy greenish image in the lower left quadrant is a different type of reflection; the giveaway being that it's in the exact opposite position as the bright image in the upper right. My guess is that the bright primary image is bouncing off the camera's CCD sensor and being projected onto a glass surface of a scope element, the greenish tinge caused by lens coating.

Those are my guesses anyway.

You just need an old beater Volvo 240 to actually drive around town; the uglier the better.

Sean Walker said:
...what in bejeezus am I doing wrong in trying to align my Celestron ASGT mount and be able to GOTO...

Sean,

Since a lot of other people have offered some suggestions, I figure I'll throw in my two cents worth. I don’t pretend to be an ASGT expert but I’ve been working with the one I bought my daughter in 2003 for the past 5-1/2 years and have trained a few others in using later versions and have run into and fixed a few glitches along the way. For the most part, the Celestron ASGT is pretty good for the money, but it has its issues. Here are some things to check.

1. The ASGT can (barely) handle a C11 or a 10” Newt, so it shouldn’t have any problem with your 6” Newt.

2. The built-in bubble level on the ASGT is not too accurate and I found one on a friend’s mount that was loose and eventually fell out. Try using a real (known good) bubble level on top of the tripod yoke platform before mounting the head, then check the reading on the head’s bubble level.

3. The manual alignment stickers on the RA and Dec axes seem to be put on by a blind person in the factory (maybe the same guy who installs the bubble levels) and are not very accurate. I suggest manually aligning the mount by eyeball, confirming that the counterweight shaft is perfectly vertical when viewed from the front and that the OTA is pointed exactly toward Polaris, regardless of what the stickers indicate. (A Telrad helps with this.)

4. Check the RA and Dec worm gears for looseness or being too tight. There should be virtually no slop in either axis and the motors should not sound like they’re straining. If you’re somewhat mechanically inclined, it’s not too difficult to adjust the gears. Make sure they have grease all the way around.

5. Although I have a Celestron polar alignment scope, I’ve found it unnecessary to get good GoTo accuracy. I just carefully eyeball Polaris so it’s visible in the center of the holes through the RA axis and that’s good enough. This takes a little practice.

6. Make sure the Latitude adjustment hardware is firmly snugged down but don’t over do it. The same goes for the RA and Dec clutch levers. The ASGT head is made of rather fragile aluminum/pot metal and doesn’t like over-torqued screws.

7. Assuming you know how to input all the required information into the hand controller, just stick with a two star or three star alignment, making sure that the alignment stars are as far apart as possible. (Sirius and Betelguese are way too close together for an accurate alignment.)

8. Does your hand controller allow you to continue through all the menus in the proper sequence as described in the printed instruction manual? I ran into one that wouldn’t and it turned out to be defective and had to be replaced.

9. Check the condition of the RJ11 connectors between the RA & Dec motors and the hand controller connector. Make sure they’re secure, clean and without damaged pins. I’ve run into bad cables that looked good and they can make you crazy. I found an intermittent cable only by testing it with a DVM. I now have my own kit for making new cables.

10. While on the subject of cables, take a close look at your Dec. motor connector cable and both RJ11 connectors. (See attached photo.) Note that there is an orientation rib on one side of the cable and the other side is smooth. When you hold both RJ11 connectors side by side with the gold contacts up, one end of the cable must have the ribbed side up as it enters the connector and the other end must have the smooth side up. If your cable has ever been replaced or repaired, and it was done wrong, the Dec. motor won’t work right because the wire sequence is reversed.

11. Are you supplying power to the mount with an A/C adapter or a 12 volt DC battery? I would recommend using a 12 volt battery (12 volt battery pack with a lead-acid battery), making sure the connector cable is fused and is in good condition. Keep the power connector cord short and check the actual voltage delivered at the connector which plugs into the mount with a DVM. Confirm that polarity is correct – center contact is Positive.

I've concentrated on a lot of mechanical and electrical issues that can affect the ASGT mount, most of which I've had problems with. It sound's like your hand controller is probably working OK, so there might be a problem elsewhere.

This is all I can think of at the moment. Good luck in getting your ASGT to work properly.