If you're shopping for astronomy gear (or anything else), I came across a cool website at Ebates.  Once you sign up, you can search through their site for a product or vendor (Orion, Amazon, eBay, etc).  You'll get a list of current discount codes and if you follow the link to the vendor's site, you'll get a percentage back on all purchases.  As I write this, the rebate from Orion is 3% cash back.  Other vendors give different amounts.

Astronomy eyepiece case

Until recently I stored my eyepieces in a fanny pack, the Barlow and laser in their boxes, and other bits and pieces stuffed in drawers.  This made for quite a handful when going out to observe and didn't protect my equipment the way I wanted.  To remedy this, I looked around for an eyepiece case.  Orion, Zhumell, and others sell dedicated eyepiece cases, and many people use Pelican (expensive!) cases.  These all do the job, but were more than I wanted to spend.  Then I found the Storehouse 18x13x6 aluminum case from Harbor Freight (item #69318) on sale for only $25.  This is about the same size as Orion's Large Deluxe Pluck-Foam Accessory Case.  It's not the up to the quality of the Pelican cases, but it will work great for the price.  The hinges and latches aren't super strong, but good enough for me.

It's hard to tell from the pictures on Harbor Freight's website, but the case comes with a 2" thick pad of pluck foam (precut cubes that you pull out to fit your gear).  It also comes with removable dividers, egg-crate padding for the top, a removable panel in the top with tool pockets, and a carrying strap.

One thing I noticed was that the foam didn't come up all the way to top top of the case.  It's about 1" shy, and that could allow items to bounce out of their slots.  To remedy that, I picked up a pack of 15x17x1 seat cushion foam from Wal-Mart.  I used one of the two pads in the pack, traced the outline of the pluck foam pad, and cut it with a utility knife.  This raised the pluck foam pad up almost to the top.

I laid out the items I wanted in the case in a fairly tight pattern, leaving a bit of foam between each piece.  This leaves plenty of space for future expansion of my eyepiece collection.

To make the openings for the items, gently slip a finger between the foam cubes and tear the strip that remains holding the pieces together.  If you're careful, they come out very neatly.  Rather than pulling out one cube at a time, you can tear around the entire shape of the item you want to insert and clear the entire slot in one piece.  For items, like a collimator, which would slip down too deep in the slot, I took the foam from the slot, cut it in half, and reinserted half of the foam back in the slot.  That way, the items are supported at the right depth.

Everything fits nice and snug in the case.  I inserted my 2" 30mm eyepiece vertically in the case.  Sitting on top of the lower foam pad, this eyepiece sticks up a bit high, but the egg-crate foam in the lid holds it securely and the case closes fine.  If I needed to, I could dig out some of the lower foam pad to allow the eyepiece to sit lower, but I don't think it's necessary.

Moving a Dobsonian telescope

My Apertura AD10 Dobsonian telescope is pretty heavy and bulky.  The base is about 31 lbs and the OTA is about 35 lbs.  There's no way I could carry them together.  I've moved them from the garage to the back yard several times.  The process involved:

1. Hugging the OTA and navigating through doors and hallways, setting it down on the carpet inside the back door.
2. Go back to the garage and carry out the base.
3. Go back to the garage and carry out the leveling base.
4. Put the dob base on the leveling base.
5. Carry out the OTA and put it on the dob base.

Not difficult, but it takes a few trips and there's always the danger of whacking the OTA, finder, or focuser on a wall or door frame.  I could carry it all down the side of the house instead of through, but I wouldn't have anywhere to set the OTA while I retrieved the rest of the parts, and it still would take multiple trips.

I read on the forums about using a hand cart to carry it all in one shot, so I thought I'd give it a try.  I picked up a Magna Cart folding hand truck.

I found mine at Sears, but I've also seen it at Costco, Walmart, and on Amazon.  The nice thing about this one is that it folds down into a nice compact package when not being used.

I used an inexpensive tie-down strap from Harbor Freight to secure the scope to the cart.  Slipping the strap under the altitude bearings prevents it from slipping off.  Without the leveling base, this would probably be all that's needed, but with the leveling base, I found the scope would tip back much further than the leveling base and I was worried about the scope's feet slipping out of the holes in the leveling base.

To remedy the problem, I built a bracket out of some scraps of 3/4" plywood.  Measure yours to make sure it will fit, but I used a piece that's 7"x14" and two pieces that are 3"x12".  The 7x14 piece is attached high enough that it clears the molded plastic of the cart.  I put some heavy duty self adhesive felt strips on all of the places where the bracket touches the dob base and where it leans on the cart, just for padding and protection.  The scope base still tips back a bit more than the leveling base, but not enough that I worry it will slip out.

This setup works really well.  I could easily roll it through the house, but I usually take it around the side of the house to the backyard.  Roll it out, unstrap it, and I'm ready to go.

Agena Astro/Starguider/Zhumell 8-24mm zoom eyepiece

For Father's Day I received an 8-24mm zoom eyepiece from Agena Astro.  I asked for this eyepiece to complement the 30mm SuperView and 9mm Plossl that came with my Apertura AD10 Dobsonian telescope.  As I'm fairly new to astronomy, I figured a zoom would be a good way to have a range of focal lengths, I'm not sure what focal lengths I will use the most.  I also wanted one that would have a comfortable eye relief for use while wearing my glasses, which my 9mm Plossl doesn't.

Before asking for this specific eyepiece, I did some research online.  Many people recommended the Meade zoom, which I considered, but I also found the Zhumell zoom, which appears to be the same as the one Agena Astro sells.  The one from Agena Astro is labelled Starguider.  It has markings for 8, 12, 16, and 24mm, but there are no stops, so you can't tell exactly where you are set.  That doesn't matter much though, as long as the view is good, I don't care about the exact focal length.

Most of the zoom lenses on the market have specs similar to the Agena Astro zoom:

• 8-24mm focal length
• 40-60 degree apparent field of view
• 15-18mm eye relief

One feature that the Agena zoom has that I didn't see listed on other brands (although they have have it as well) is that you can pull off the rubber eye cup and there are T threads underneath.  You can get a T adapter for a DSLR camera and mount it directly to the eyepiece for projection astrophotography, which I will try at some point.

They eyepiece comes with covers on both ends, which I read some other brands don't.  It also comes in a nice bolt case, which protects the eyepiece quite nicely.

One thing to be aware of is that the filter threads at the bottom of the eyepiece are obstructed by the inner workings of the zoom.  I found I could only screw my moon filter on about half way.

So, how does it work?  Quite nicely!  The field of view at 24mm isn't quite as wide as my 30mm SuperView, but it still covers a good area.  The image was crisp and bright at 24mm.  Zooming is done by twisting the textured barrel, which rotates smoothly.  As some reviews noted with the Zhumell zoom, it isn't parfocal.  As you zoom in and out, you need to refocus a bit.  

When zooming in, the image dims significantly, as expected.  Switching to a smaller focal length fixed eyepiece has the same effect.  For bright objects, like planets, zooming all the way in might work well.  I found I wasn't going further than about 12mm most of the time.  I haven't tried it Barlowed yet, but I expect it to work well at 2x.

I found it comfortable to view with the eyepiece with my glasses at all focal lengths.  The rubber eye cup folds down, so it's easy to get closer.  I didn't have to move around to see the full field of view like with my 9mm Plossl.

Overall, I'm quite happy with this eyepiece.  Eventually I will probably buy some fixed focal length eyepieces with wider fields of view, but this zoom should keep me happy for quite a while.  The price is quite reasonable too.

Some observing, a light shield and knob for my AD10, and an observing "hood"

I was finally able to get out and do some observing.  It's a pain that it gets dark so late, and in my area, it quite often clouds over just as it's getting dark this time of year.  Anyway, I was able to use my leveling base and setting circle for the first time.

For my first object, I didn't need to use the setting circle.  I pointed my scope at the constellation Lyra, centering it right between the stars Sheliak and Sulafat in my finder.  I popped my 30mm eyepiece in and there was M57, the Ring Nebula.  It was quite small, so I switched to my 30mm with the 2x Barlow and got a better view.  Finally, I switched to my 8-24 zoom eyepiece.  After a bit of experimentation, I found my best view at around 12mm.  8mm gave a larger view, but it got a bit too dim.

After enjoying that view for a bit, it was time to try out the setting circles to find my first globular cluster, M3.  I went back to the 30mm and centered my scope on Arcturus.  Checking SkEye on my phone, I found the altitude and azimuth, set the azimuth pointer on my base, and noted the altitude on my Alti-Gauge (which was off a little over a degree).  I then found the coordinates of M3 and swung the scope to that locate.  I didn't see M3 in my field, so I started panning around a bit.  There it was, just outside my view, very easy to spot in the 30mm.  Again I went to my 8-24 zoom and found 12mm was the best view.  At that setting, M3 was still bright enough to see clearly and I was able to resolve many stars.

I tried for M92 and M13, but they were very close to the zenith and I didn't have any luck.  I also tried for M51, but also no luck.  I probably looked at it but couldn't see it due to the light pollution.

Speaking of light pollution, I tried a couple of different things to help out.  First, I made a light shield for my Apertura AD10 dobsonian telescope.  I've read that this has made a difference for some people, but I didn't find any benefit from it myself.  Here's how I did it if you want to try anyway.

The best paper I could find was black poster board from Wal-Mart.  Other stores carried stuff they called poster board, but it was more like construction paper and was pretty floppy.  The Wal-Mart stuff is quite thick and stiff.  First, I laid out two sheets overlapping a couple of inches and aligned as straight as possible. Lay them out the long direction. I used packing tape on one side only to attach them together.  As you can see in the picture, the paper is more dark grey than black and is kind of shiny.  To cut this down a bit, I sprayed what would be the inside with flat black paint.  I didn't put tape on the inside because it's shiny and painting over it would cause the paint to flake off into the scope, not a good idea.

Next, I measured around the circumference of the end ring of the scope, which came out to 38.5".  I measured and marked the paper and that position, then cut off the extra a couple of inches past my mark.  I put tape along the edge that will be the bottom of the tube to reinforce it.  I then rolled the paper, lined up with the mark, and used more tape to complete the tube.

This light shield slips over the end of the scope and stretches very slightly to slip over the four mounting screws for the spider, giving a very secure fit.  Look through the focuser without an eyepiece and you can see whether it's obstructing the view at all.

I tried the light shield, and to test whether it made a difference, while observing M3 I pulled off the light shield.  I couldn't discern any difference in the view, contrast, or background with the shield on or off.  I also tried looking at some objects when I was facing my neighbors yard, where they have a very bright patio light.  Still no difference.  It may work better if I actually flocked the light shield instead of just painting it, but I don't know if I'll bother with that.  I would like to flock my scope tube at some point, hopefully that will help.

Notice that when the light shield is on, the end of the scope is covered so you can't grab it to point the scope.  To deal with that, I installed a nice "comfort grip" knob.

I used part 60975K75 from McMaster-Carr.  This is a 1.5" diameter round knob with a 1/4-20 insert.  The knob is positioned below the spider mounts so the light shield fit properly.  To drill the hole, I laid the scope tube flat, masked off the area to catch all of the scraps, and carefully drilled a 1/4" hole.  I vacuumed the scrap out after drilling.  Make sure none of scrap falls down to the mirror.  I used a 1/4-20 stainless bolt, two washers, and a nylon locknut for mounting.  I painted the head of the bolt and one of the washers flat black before installing.

Although the light shield didn't help as I had hoped, I did find another suggestion online that is a bit benefit.  Some people throw a towel over their head to block out stray light (insert Hitchhiker's Guide To The Galaxy joke here).  This works ok, but is a bit awkward.  The suggestion I found was to use a dark T-shirt, slip it over just your head, then pull it up over they eyepiece to observe.  This worked very well, especially when I held it closed under the eyepiece as well, to block out reflection from the ground.  I had to be sure to leave some opening though, otherwise my breath would start to fog the eyepiece.  I am thinking of a design to deal with this.  I'll post it if it works out.

Denver observing chair

One problem with a dobsonian mounted telescope, like my Apertura AD10, is it's hard to be comfortable without a good chair.  A regular height chair is ok if you're looking at objects that aren't too high or too low in the sky.  If you want to observe something near the horizon, you really need to bend down.  And if you want to view something high in the sky, you'll have to stand up.  But for someone relatively tall, like me at 6'2", you can't stand up straight to observe, you need to bend down to reach the eyepiece.

The solution to this is an adjustable chair of some sort.  There are commercially made observing chairs, such as the one from OpticsMart, but they are quite expensive.  If you don't mind spending the cash, they are a nice way to go.  Something like a drummer's throne or shop stool would probably work as well, but you need to be sure they can go as high and as low as you need for observing.  Again, they cost money...

I decided to go the cheap DIY direction.  There are many designs online for observing chairs, and they aren't hard to make.  One I was considering was an observing stool.  A nice, simple design.  In the end I ended up building a design called a Denver chair, designed by Charles Carlson of the Denver Astronomical Society.  Click here to take you to the page with the design.

Here's how my chair turned out:

The design on the page linked above is very simple to build and well described, so I won't go into details here.  Be sure to find a nice straight, splinter free 2x4.  I did deviate slightly from the design.  Instead of the non-slip tread strip, I routed some 5/8" grooves along the back that the mounting bolt can slip into.  I made the grooves 3" apart.

As you can see, I also padded and covered my seat.  For the seat, I used a scrap of 3/4" MDF instead of plywood.

Since I covered my seat, beveling the back and having it ride against the front of the leg like the original design wouldn't work.  Instead, I beveled the piece of 2x4 on the bottom of the seat at the same 22 1/2 degrees as the legs and attached it flush with the back of the seat.  I then cut some pieces of rubber and screwed them to the back of the 2x4 to protect the finish of the leg.  For the rubber, I cut some pieces from a cheap rubber bungee cord.

When assembling the seat, be sure to add a spacer of some sort so the vertical plywood pieces are a bit wider than the 2x4.  Another option is to sand the sides of the leg a bit.  This is needed so the seat can slide up and down the leg easily.

Dobsonian leveling base with setting circle

I haven't done much observing recently, mostly due to weather.  First we had wildfires nearby, so standing around outside wasn't a good idea healthwise, not to mention the bad seeing.  And now it doesn't get dark enough to see anything until close to 9pm, and around that time clouds often roll in.  In the meantime, I've been keeping busy building some things to enhance viewing when I do get out.

The first thing I built was a leveling base with a setting circle for my AD10 dobsonian base.  This design should easily adapt to any dobsonian mounted telescope with some adjustments to sizes and positions.

Link to PDF plan for my leveling base.

Link to PDF detail of foot

Link to PDF of setting circle (print at 24 1/2", not 19")

I laid out my base using a 2'x4' piece of 3/4" plywood.  They call these "project panels" at Home Depot.  The base doesn't quite fit on one piece, so I cut it off around 27" wide and glued a strip about 5" wide along the bottom edge to complete the circle.  If you've got a full sheet of plywood, you don't need to worry about this.  The way I have it laid out, the glued on strip doesn't take any of the load.  The other parts you'll need are three leveling feet, knobs, and tee nuts.  I used bolt-down swivel leveling mounts, (zinc plated, 3/8"-16x4" long, part #2531K31), comfort-grip five arm knobs (3/8"-16 insert, 2 1/4" diameter, part #61125K13), and some 3/8"-16 tee nuts from Home Depot.

Once the glue dries, draw a circle with a 12 1/2" radius with the center a little over 13 1/2" from the edge opposite the glued strip.  From the center of the circle, draw a line straight up to the edge opposite the glued on strip.  Draw a couple more lines from the center at 120 degrees on each side of the first.  These lines will locate the lobes for the feet.  Mark a spot on each line 10" from the center.  This will be the location of the holes for the feet on the AD10's stock base.  Note that I deviated from my PDF plan and put these holes in line with the leveling base's feet.  It doesn't really matter, I just figured since I'd already drawn my lines, I would put the holes there as well.  

Print out the PDF detail of the foot full size.  Cut out the pattern and trace the shape at the appropriate location based on the lines you drew on the circle.  Get them as close as possible, but the exact positioning isn't critical.  Also mark the positions of the holes where the leveling feet will be mounted.

I used a jigsaw to cut the perimeter of the base slightly outside the line, then a random orbit sander to take it down to the line.  I also used the RO sander to round over the edges slightly.  Using a drill press, I drilled 1/2" holes for the leveling feet and 1 1/8" holes for the AD10's feet.  I also drilled a 7/16" hole about halfway through at the center to give clearance for the center bolt of the AD10's base.  I set the AD10's base on top and used a rat tail file to adjust the large holes to fit the AD10's feet.  I worked a little bit at a time until the feet slid snugly into the holes without any play and the AD10's base sat flat on the leveling base.  I made a mark with a silver Sharpie on the leveling base by one of the holes and on the bottom of the AD10's base by the corresponding foot so I could be sure to always get it in the same position.  I finished the base with spar varnish.

I found the setting circle PDF on the Cloudy Nights forums.  Unfortunately, I don't know who originally generated this PDF, or I'd happily give credit here.  I took the original and trimmed the white space around it.  The original is for a 19" setting circle, but for my design it needs to be a bit bigger.  I took it to Kinkos and had them print it at 24 1/2".  After printing, I used a black marker to touch up a few spots that didn't print well, then I carefully cut out the circle.  I had Kinkos laminate it, trimmed the lamination about 1/8" larger than the printout, and made oversize cutouts for the AD10's feet and central hole to allow for positioning adjustments.

Note that I positioned it with the 270/90 degree position by the foot I had marked.  This puts the 0 degree position on the left side of the scope.  By doing this, I can have the pointer on the side by the eyepiece instead of directly under the scope.

I placed the setting circle on the leveling base and the AD10's base on top of it.  I shifted the setting circle until I had it as evenly positioned around the base as possible.  It may not be perfectly centered on the leveling base, but that doesn't matter.  The important part is that it's centered under the AD10's base.  Before removing the AD10's base, I used masking tape at several positions around the outside to hold the setting circle in position.  After removing the AD10's base, I flipped back half of the setting circle and glued it down with contact cement.  When that was secured, I flipped back and glued the other half.

To complete the base, I pressed the tee nuts into their holes from the bottom of the base, using a vise to squeeze them tight.  I ran the leveling feet up through the tee nuts, ran a nut down the threaded shaft a ways, screwed the knobs on as far as they would go, then ran the nuts back up against the bottom of the knobs, using a wrench to jam them as tightly as I could against the knobs.

For the pointer, I bent a piece of .064 music wire from the local hobby shop as needed and epoxied it into a 1/4" coupling nut.  To hold it on the base, I put the AD10 base on the leveling base and centered it at 0 as closely as I could and attached several rare earth magnets (from Home Depot) along the edge of the base around the position where the 0 degree mark was.  I can adjust the pointer to exactly where it should be without worrying about exactly alignment of the base.

When I take my scope out, I can plop the leveling base down, point the 270/90 degree mark roughly at North, use a torpedo bubble level to adjust the base, put the AD10 on it, point at something in the sky, check the current azimuth using a cell phone app, and position my pointer at the objects position.  

This should work great for the azimuth, but what about altitude?  People have done pointers on the sides of their dob's bases for that, but I decided to go the easy and hopefully more accurate way and got an Alti Gauge from OpticsMart.

This is just like the Wixey digital level many people use, but with an astronomical enhancement.  The Alti Gauge has a dim red backlight.  The unit has a magnet in the bottom that attaches to the scope's tube.  You turn it on it and tells you the altitude you're pointing at to 0.1 degrees.  

I'm looking forward to making use of my setting circles, as star hopping in my light polluted skies is pretty difficult.  I hope this information is of use to others as well.

UPDATE: 

I was able to get out with my scope and use the setting circle.  It worked pretty well.  I was able to navigate to a few objects, although not dead-on.  I found that it worked best to point at something I could easily see near where my target was, adjust the azimuth pointer to that object and note the altitude of it, then slew to the coordinates of my target.  This would get me close and I was able to find my targets by panning around a little bit.

The azimuth worked quite well, but the altitude is off a degree or two.  I think I need to zero my Alti-Gauge. Due to it being off a little bit, I had to subtract the difference from what SkEye on my phone told me the altitude was. I'll try zeroing my guage the next time I'm out.

Overall, I'm quite happy with the results.