Turning Stepper Motor Off

@will Almost forgot pictures of the unit so you can gauge the size.

Posted by: @zander

So how did your mental image match to the real thing?

I didn't even come close 🙂 I was thinking more along the lines of a gyroscope !

I am curious though why you'd need to rotate the azimuth and/or the elevation at 2 RPM ? Is that just the instantaneous speed you want to achieve without actually spinning it through 2+ revolutions ? 

@will Maybe my calculations are way off, let me think out loud here and see where my flaw if any is.

2 revs per minute or 720 degrees in 60 seconds. Thats 360 in 30, 180 in 15, 90 in 7.5, 45 in 3.75.

I simply held my arm out straight and moved it 45 degrees while counting. I think I am at least +- 20%.

Make sense?

EDIT, yes instantaneous speed, no need to go thru even 1 rev.

The cables are tied together, and tied to the tripod with tiny bungees so they stay neat and don't catch on anything. So far it has always worked.

@zander 

Yep, makes sense to me and I also get 3.75 seconds to turn 45 degrees.

If you wind up using steppers, check out the AccelStepper library. It allows you to set acceleration which can be used to start the rotation slowly and build up to speed and then slow down slowly as well. That should allow you to bypass excessive rocking as the inertial effect of starting a rapid turn might cause.

You should be able to get better than 3 degree accuracy in both horizontal and vertical accuracy. I'm still not sure how you intend to separate the two rotations 90 degrees apart, but I guess you have a plan 🙂

@will There are 2 motors. The round thing on the bottom that attaches to my tripod is the horizontal motor, the vertical is a little harder to see but if you look at this picture the 5 inch mark is directly in line with the tilting surface It rotates between those 2 beefy arms that stick up.

@zander canon, right?

@darup Yup, 7D Mark II with 100-400 lens and 24-105mm for my regular lens.

@will Bigfoot? & Jack?  Now there is a pair!

@zander mostly Nikon & Sony Alpha.  Have the big lens for both.  Did wildlife & humans.  I tried stars & planets - didn't work for me at the time.  My current epoch is 2014.  Photo is on the sideline.  Tried photoshop - skills got flushed.  Gimp hurts my brain at the moment.  Airborne photo is sorta my thing now if the rules would quit rock'n the boat! (oops drone)

@darup Nice gear. If I was starting today, I think I would go with Sony as long as they have a high ISO camera like mine. I once had a side hustle photo business, did animals and confirmations. Just one of those big Italian families will buy you a lot of gear, sent pictures all the way to Italy, they must have bought at least 100 medium sized prints and a couple dozen 8x10's.

Astro is a pain, up all night, clouds and planes and now Musk's sats, too many issues. I use Lightroom, my brain can't handle photoshop besides they are for totally different purposes, LR is for photo finishing, PS is special effects.

I am going to get one of the legal drones, under a certain weight I think.

@zander

Posted by: @zander

legal drones,

Drone:  think carefully before you plunk your money down.  The rules in the states are probably quirky and fluid - probably the same in Canada.  Check them VERY carefully (worse than 18650 qualities/capabilities/avoidance).

Here (just a quick summary - the detail is horrific and the penalties are said to be astronomical):  259 grams max without registration but does NOT exclude rules and penalties and conformance; 51 lbs max weight without exception from FAA; basically cannot fly in controlled airspace; cannot fly near airports without permission; 400' maximum altitude; must personally see drone at all times while it is airborne or have a spotter; and it goes on and on because of the people who violated the space and rights of other people, property, animals, and more.  Oh, DJI, if you are looking at this one -- Great Drone; however, it must be activated using a very short-list of expensive mobile phones with the DJI app if you can get the app installed on the mobile device. Oh, compensation of any kind (barter, trade, money, lunch(?) of any kind is consider doi'n it for business and at a minimum a 2nd class medical (some get by with BasicMed), Lots of insurance (more than a car, RV, etc), written testing and ... !) is a BIG issue if caught.  About the only place that one can fly without being trashed by rules and laws is inside and under conver.

A lot of the pictures of "Wonderful" places can no longer be taken by a drone operator because inconsiderate folks did stuff they shouldn't because they felt they could and they cared less about the impact they emotional, physical, and ... !

So, Legal?, you bet, it just takes adjustment, adaptation and knowing the rules and following them!  Canada, too.

I hope to do the Great Wall of China - yea, I know it is just a reproduction that they allow visitors and tourists to step foot and view.  Paperwork is underway.  When?  Work'n on it!

@darup I live in Canada, FAA is not relevant here. I am free to fly a drone weighing less than 250 grams everywhere it is legal to fly a drone. Fairly common sense but of course we have yahoos too. According to the Canada Transport Agency (similar to your FAA) we "do not need to register the drone or get a drone pilot certificate."

Here is the main info for Canadians

While there are no prescriptive elements of the regulations, there is an expectation that the pilot of a micro drone to use good judgment, identify potential hazards, and take all necessary steps to avoid any risks associated with flying your drone.

As a good practice, you should always:

• maintain the drone in direct line of sight
• do not fly your drone above 400 feet in the air
• keep a safe distance between your drone and any bystanders
• stay far away from aerodromes, airport, heliport and waterdrome
• avoid flying near critical infrastructures
• stay clear of aircrafts, at all time
• do a pre-flight inspection of your drone
• keep the drone close enough to maintain the connection with the remote controller
• avoid advertised events

Like I said, all common sense except for the 400ft rule. I didn't know about that before and don't like it but what can you do.

Posted by: @zander

@inq Cost for an entry level decent one was about $2,000, no idea now with everything going up, really well built amateur telescope mounts can get into the low 5 figures. Here is a mid price telescope mount, that aint going to fit in my backpack. Really good ones go for double that and more.

https://www.bhphotovideo.com/c/product/1599592-REG/celestron_91531_cgx_l_goto_eq_telescope.html

I don't know if this is something you can adapt, but it was what I was thinking when I mentioned that.  I'm sure it is relatively junk compared to the German item.  It also appears they use the same mechanism on larger telescopes... that Economy of Scale thing.  $380

"https://www.amazon.com/Celestron-114LCM-Computerized-Telescope-Black/dp/B0038R0MRI/"

https://www.amazon.com/Celestron-114LCM-Computerized-Telescope-Black/dp/B0038R0MRI/

@inq Funny man.