54 replies to this topic

[Lizardman]

Goto and tracking are what brought me back into the hobby. No brainer for me.

[Spikey131]

I have a 12.5” push-to Dob and a 16” with goto and tracking.  Both have excellent ergonomics and are very smooth to push and track manually.  As Jon Isaacs mentioned, tracking is a skill that I have learned and I am comfortable viewing objects at high magnification and tracking them manually.  That being said, it is nice to have the mount do it for you.  So tracking is valuable and worth getting if you can.

 

But the OP is talking about a 10-12” Dob that he can travel with on commercial airlines.  For this, one will need the most compact Dob possible.  So forget about tracking for this application.

[KBHornblower]

I have a goto mount that I never use. But some day I might.

I don't even use slow motion controls.

 

But planets do move faster than the rest of the sky.

My bold.  They move at a rate that is imperceptibly different from that of the background stars in the time the stars drift across an undriven field of view, and they are faster only during retrograde apparent motion.

[Echolight]

My bold.  They move at a rate that is imperceptibly different from that of the background stars in the time the stars drift across an undriven field of view, and they are faster only during retrograde apparent motion.

Well. Even the planets don't all move at the same speed.

 

As far as imperceptible, stuff that is mostly imperceptible gets thrown about like wildfire on this forum  .

Minutiae as a means to an end. 

 

I will say, that it takes the Moon nearly an hour longer each day than planets to appear in the same location!

 

But maybe it is just the high magnification and resulting small field of view that makes tracking more valuable, regardless of the object viewed. However, planets are almost exclusively viewed at as high a power as they can be and stay sharp at.

[Jon Isaacs]

Well. Even the planets don't all move at the same speed.

 

As far as imperceptible, stuff that is mostly imperceptible gets thrown about like wildfire on this forum  .

Minutiae as a means to an end. 

 

I will say, that it takes the Moon nearly an hour longer each day than planets to appear in the same location!

 

But maybe it is just the high magnification and resulting small field of view that makes tracking more valuable, regardless of the object viewed. However, planets are almost exclusively viewed at as high a power as they can be and stay sharp at.

 

It would be impossible to determine that the planets moved at a different rate than the stars by drift timing.  You would have to compare the motion of the planet with the star field.  Currently Jupiter is moving about 0.6 degrees per day against the star field.

 

That means if the Starfield took 60.0 seconds to cross the field of view, Jupiter would take 59.9 seconds, a difference of 0.2%.  I have to think that qualifies as imperceptible.  It is not immeasurable but it is imperceptible.

 

The biggest difference in time is takes objects to cross the field depends on their declination.  The declination of Jupiter is about 15 degrees, that means it takes about 0.4% longer to cross the field. a few years back, it was at -22 degrees, that took 0.7% longer.

 

Jon

 

 

 

[Jon Isaacs]

Well I said that maybe it's just due to the fact that they are viewed exclusively at high power.

 

So what's your point?

 My point is that the looking through the eyepiece, the rate at which the star fields travel and the planets travel is imperceptible. 

 

Manual tracking at high magnifications is quite doable.. 

 

Jon

[MarkMittlesteadt]

 My point is that the looking through the eyepiece, the rate at which the star fields travel and the planets travel is imperceptible. 

 

Manual tracking at high magnifications is quite doable.. 

 

Jon

Viewing planets at high power through an already narrow FOV, like through a long focal length Mak, they go through the EP quite fast (like within seconds). Is manual tracking doable? Yes. Preferred? Not so much. For me anyway. 

 

Besides, I get interrupted quite often (for a variety of reasons). Being able to come back to the EP and see the planet still in the center of the FOV is something I'm grateful for. 

[Dennis53121]

Better than 95% of the time I use push to mounts with no tracking and no slow motion control. For me I have never had any problem even at high powers. Slow motion for me is typically just with one finger and in combination with a capable tripod damping is within one second. 

 

Dennis

Edited by Dennis53121, 29 September 2023 - 02:31 PM.

[ButterFly]

Humans are rather good at detecting asymmetries.  It can be irksome.  When tracking something, if you want it to be in the middle, and it's not, that can be distracting for our feeble brains, which already ignore well over 90% of the visual information we receive.

 

ServoCAT can track solar system objects at their native rates.  You just have to be on that catalog entry to get that particular rate.  Planets are rarely a two minute observation.  Sitting down and watching the thing for half an hour is a short session!  That's a lot of drift, but more importantly, off ceneteredness.  In addition to the asymmetry distracting the brain, there is lateral color of eyepieces.  Every eyepiece exhibits lateral color.  It can be hard to notice when the target is drifting across the field, but when one places the target somewhere and leaves it there, it's noticeable.  And this is all with a coma corrector on a dob.

 

Having the ability to turn off tracking, or tracking at sidereal rate makes it pretty plain to me that tracking solar system objects at their native rate is indeed a LOT better.  Nudging it back with the AVX is annoying, but it would be a lot more annoying if I could go to the powers I can with my dob in good seeing.

 

Again, here, one isn't going to a different hemisphere to view Saturn.  Nonetheless, custom rates are not difficult for a controlling computer to handle, and much of it can be taken care of with a speed dial on a platform.

[ShaulaB]

Learn the sky. It pays off in the long run.

[Echolight]

 My point is that the looking through the eyepiece, the rate at which the star fields travel and the planets travel is imperceptible. 

 

Manual tracking at high magnifications is quite doable.. 

 

Jon

I do manual tracking also.

 

But I understand why some people don't.  Or prefer auto tracking. Keeping the object in the sweet spot. Especially for planets where the details can come and go. Lucky seeing.

[Echolight]

Better than 95% of the time I use push to mounts with no tracking and no slow motion control. For me I have never had any problem even at high powers. Slow motion for me is typically just with one finger and in combination with a capable tripod damping is within one second. 

 

Dennis

I think the big advantage to tracking is that it keeps a planet in the center, where the view is most pristine.

 

On the Moon, I prefer to bounce around.

[Alex Swartzinski]

This topic comes at an interesting time for me.

 

I've always enjoyed my manual dobsonian mounts. They are incredibly simple and intuitive to use.

 

I'm a starhopper who is fine with only seeing 10-20 objects in a night. I'm just happy to see any DSO, and I try to really soak them in! I also like the journey of hopping across the sky.  Locating a quasar or galaxy discovered a few decades ago by myself is very satisfying. 

 

I've been around a few GoTo scopes, and they always take longer to get up and running. Sometimes they don't work right either.  I've always enjoyed the tracking aspect of these scopes though. I don't mind manual tracking, but it's pretty sweet to walk away from the scope and return to the same fov, especially since I really like 68-70 degree long eye relief eyepieces. 

 

Tomorrow I will get my first EQ mount since the Powerseeker 127 EQ I entered this brilliant hobby with. I found a Tom Osypowski EQ platform 20 minutes away, and it's a really good price. 

 

I hope this platform will allow me to have those nice tracking views when I want without compromising the zero electronics nature of my scopes. When I want tracking for high powers, it's there as an option, but I can also leave it at home. 

 

We'll see how it goes, but I'm excited to add this capability to my scopes.

 

It will be interesting to see how I get on with it... 

Edited by Alex Swartzinski, 29 September 2023 - 06:42 PM.

[CHASLX200]

 My point is that the looking through the eyepiece, the rate at which the star fields travel and the planets travel is imperceptible. 

 

Manual tracking at high magnifications is quite doable.. 

 

Jon

Ya it is. I have even done 1150x in a 14.5" Starmaster. But it is no fun.

[CHASLX200]

Goto and tracking are what brought me back into the hobby. No brainer for me.

I loved the LX200 when it fist came out. I dreamed of a GO-TO scope back in the 1970's where it can find stuff for you. I had my fun with it for a few years. 90% of the objects i looked at were not much to look at. So i got it out of my system.

[Jon Isaacs]

I do manual tracking also.

 

But I understand why some people don't.  Or prefer auto tracking. Keeping the object in the sweet spot. Especially for planets where the details can come and go. Lucky seeing.

 

I understand the advantages of tracking.. I have found that I prefer manual tracking for observing at high magnifications, tracking that really works, can be a real advantage.  For my Dobs, (not the 22 inch) I have a high end Tom O. dual axis equatorial platform.  It is solid, it is easy to setup, it weighs less than 30 lbs.  I can carry it with one hand very easily.  

 

 

But I have found I just prefer tracking manually. That is just the way I am.  

 

 

Humans are rather good at detecting asymmetries.  It can be irksome.  When tracking something, if you want it to be in the middle, and it's not, that can be distracting for our feeble brains, which already ignore well over 90% of the visual information we receive.

 

ServoCAT can track solar system objects at their native rates.  You just have to be on that catalog entry to get that particular rate.  Planets are rarely a two minute observation.  Sitting down and watching the thing for half an hour is a short session!  That's a lot of drift, but more importantly, off ceneteredness.  In addition to the asymmetry distracting the brain, there is lateral color of eyepieces.  Every eyepiece exhibits lateral color.  It can be hard to notice when the target is drifting across the field, but when one places the target somewhere and leaves it there, it's noticeable.  And this is all with a coma corrector on a dob.

 

Having the ability to turn off tracking, or tracking at sidereal rate makes it pretty plain to me that tracking solar system objects at their native rate is indeed a LOT better.  Nudging it back with the AVX is annoying, but it would be a lot more annoying if I could go to the powers I can with my dob in good seeing.

 

Again, here, one isn't going to a different hemisphere to view Saturn.  Nonetheless, custom rates are not difficult for a controlling computer to handle, and much of it can be taken care of with a speed dial on a platform.

 

One quickly learns that the object does not need to be in the middle of the field.  I can imagine it bothers some.  

 

If one is manually tracking, then well corrected eyepieces and telescopes free of aberrations like coma are important. In F/4 or slower Dobs, Type 6 Naglers with a Paracorr 2, these provide very sharp views of the planets across essentially the entire field of view.  Lateral color is not an issue. 

 

My primary planetary scope is my 13.1 inch F/5.5 Dob.  Many would not use a Paracorr at F/5.5 but I do, it dramatically increases the size of the "planetary sweet spot", it is the entire field of view... 

 

I am not claiming manual tracking is the optimal solution but it is certainly a workable solution.  Over the years, one learns.

 

Jon

[ButterFly]

I prefer high power planetary views without lateral color or coma with an ADC in the train, held steadily while I wait for those moments of excellent seeing.  Others don't, but I don't really care.

[star acres]

Right now, my step outdoors viewing situation is a bit better than " The Honeymooners". I'm glad for whatever I see and when the weather clears up. Real tracking is for some astrophotography. My telescope aims very smooth and that's good enough for an eyepiece.

[Scott99]

I've used alt-az mounts most of the time over the years, without tracking.  But tracking is a nice luxury, I'd prefer to have it every time if I could- especially as the scope gets larger.  You spend more time at high power. 

 

However, I wouldn't mind giving up tracking to get to dark skies....you have to do whatever it takes   

[Sebastian_Sajaroff]

The tracking need depends mostly on your eyepiece field and magnification.

 

At 200x, Jupiter crossed my 68° field on 80 seconds.

Had to push the tube every 40 seconds or so.

Feasible but distracting.

 

An EQ mount would have simplified the problem, you just push on the RA axis (not on both Alt-Az directions).

[davidgmd]

For planets or other small objects at high mag, I prefer either motors for tracking or slo-mo controls to manual pushing. Motors and slo-mo controls make it easy to keep the object centered without overshooting or having to take my eye away from the eyepiece. Motors for tracking are easiest but at the cost of added weight, complexity, and… cost. It just about balances out for me.

  
I need help finding things. Due to lack of experience and light pollution where I observe. Digital setting circles with push-to meet that need as well as computerized GoTo mounts. Both have a bit of a learning curve but can be simple enough. Both can be connected to third-party planetarium apps, which increases complexity and opportunity for failure. Both require alignment. Usually a quick and easy level and North (or South) for my alt/az mounts and GPS does the rest. None of my mounts lose track of where they are regardless of clutch settings.

[jesse 3]

As someone mentioned, there is no strong need to travel to dark site to see planets. I use EQ tracking for high power planet observation. Manual can also work. Make sure scope is locked and not moving when you change eyepieces.

For DSOs at dark site, manual is faster and more enjoyable.

[seasparky89]

I have no problems with manual tracking, since I have been doing it for decades.  But, at our club’s public events, I wouldn’t think of not having tracking.  At higher powers, especially on the planets, IMHO, the average observer really would have issues, and I would be very busy constantly repositioning the scope.  Yes, it’s a trade off with lugging and setting up my tracking platforms, but once set up, it really makes viewing so much nicer.

 

Stan

[MarkMittlesteadt]

I was out last night looking at Jupiter using my new Baader 8-24mm zoom. It was low in the sky and not the greatest seeing conditions.

 

With my AZGTi, I manually centered Jupiter in the EP, chose Jupiter in the SynScan app as the target and chose Point an Track. It kept it in the center of the FOV from the time it rose in the East at 8:30 until well past 10PM. And that was even without an accurate alignment. 

 

I most frequently use my AZGTi manually, with only extremely minor adjustments electronically, and the Point and Track feature is fantastic. 

 

[N3p]

If the goal is to take the telescope in the plane, I would certainly get a ultra light/compact dobson where everything fits in a box + maybe a thin truss package.

 

I use a RA tracking newtonien telescope 8" on EQ mount and my larger 12 manual dobson. Tracking is very, cool and fun for the task of sketching at high power, like the moon and the planets.

 

Tracking was too much problems for me with the 12" so I learned to track and sketch with a manual telescope, it can be done, it's a bit less fun, more complicated but it certainly can be done. The extra details on the moon and planets with the 12" mirror is also a very decent motivation to sketch with the manual telescope.

 

Manual is very reliable with less mechanics, electronics, batteries.

Edited by N3p, 03 October 2023 - 12:23 PM.