Test using SKEye free Andriod App as 'Push To' finder

[Eastridge]

I am posting this in it’s own thread so that it has a directly relevant title but it duplicates my post to the thread ‘Advice on converting Dobsonian to GOTO’ which gives full background discussions etc.

I managed a field test last night using the free Andriod SKeye app in Indirect Mode to give Push To functionality with my 10” Dob., full details below but in summary – based on what we did it works well enough for us, not 100% accurate but gets you to having object in finderscope and we can go from there ourselves.

WHAT WE DID:

Followed SKeye instructions found here( http://lavadip.com/media/SkEyeIntro.pdf ) specifically:

Checked location co-ordinates in SKeye app were accurate

Check clock setting on phone accurate ( free Clocksync app)

Did 'figure of 8' move to sort magnetic field distortions right by where phone will be held.

Phone ( Galaxy Note) held with sticky tape onto polystyrene packing for OTA and that held to OTA with car luggage strap, non slip mat between as that has been mentioned elsewhere as being good for disrupting magnetic field.

Aligned as per instructions to Jupiter, Betelgeuse & Rigel ( only south portion of sky visible from location due to garden landscaping works). As this was just a test we were not overly precise about this put object in cross hairs of finder and then confirmed it was ‘centrish’ in 8mm EP.

Couldn’t get to the mentioned ‘Insta align’ function so did all 3 manually.

RESULTS:

Using ‘push to’ searched for M42 – when SKeye showed it as centred it was toward bottom of finderscope view.

Used ‘push to’ for Pliédies – again there but toward bottom

Used ‘push to’ for back to Jupiter – again slightly off to the bottom , which seems odd as we used it as the first alignment object, but the system is using averaging.

I wonder if we knocked the scope slightly at some point during the alignment process or something but it still ‘did the job’ if not with perfect accuracy.

We are now happy enough that we will buy some bits and bobs to get a less cumbersome phone mount, a cheap case and some foam to pack below to keep it from rocking + to reduce magnetic field issues.

When we have access to a fuller portion of the sky that will give the ability to choose more diverse alignment points which I would assume would make it more accurate as well.

Hope this helps anyone else considering cheap (presuming you have a smartphone already) ways of getting quicker finding

[boss hogg]

Hi Eastridge

Quick question :- what phone are you using?

I like the concept! but wonder if the phone mount might not be aligned accurately enough?

look forward to hearing further reports .

Colin

[sparkyjon]

i have the same phone but i run google sky map as i find it much better , it has a better night vision mode as it dips the brightness as well as turning the screen red, i also have mine attatched to my sct with a phone cradle this gives you a little movement option,

what i did when i used it is pick an easy target , orions belt is an easy one , line it up then adjust it so what i'm seeing is in the centre of the phone , then usually thats it the rest is easy enter into the search it guides you to what you want to view and your generally in the area, i use my finder scope and double check on the rdf and 9 times out of 10 it bang on the middle of my fov..depending on EP that is..

[Steep]

My N7 was driving me nuts last night, after extolling the virtues of android apps to find your way about the sky mine was constantly way off, it didn't even enter my mind that the tube might be the cause of the problem. After reading this and the other thread I chucked a compass app on the N7 and tested the field near the scope, from about 2 feet away up to the tube itself theres an 8 degree swing in compass direction and that explains a lot. Cheers Eastridge!

[Eastridge]

Hi Eastridge

Quick question :- what phone are you using?

I like the concept! but wonder if the phone mount might not be aligned accurately enough?

look forward to hearing further reports .

I am using a Samsung Galaxy Note, we tried hubbies Samsung Galaxy Ace but that seemed much more susceptible to the magnetic fields & from reseasch it seems different phones have very different levels of shielding.

I think you are right we need to take more care on alignment to get it spot on - will do that once we have the new holding mechanism in place.

Colin

[Eastridge]

i have the same phone but i run google sky map as i find it much better , it has a better night vision mode as it dips the brightness as well as turning the screen red, i also have mine attatched to my sct with a phone cradle this gives you a little movement option,

what i did when i used it is pick an easy target , orions belt is an easy one , line it up then adjust it so what i'm seeing is in the centre of the phone , then usually thats it the rest is easy enter into the search it guides you to what you want to view and your generally in the area, i use my finder scope and double check on the rdf and 9 times out of 10 it bang on the middle of my fov..depending on EP that is..

Thanks will have a look at Google Sky maps

[pduk]

I'm interested in trying this soon as well. I'm wondering whether plonking the phone on top of the telrad might be enough of a gap - if so I could probably rig something up with one of the cheap car mounts from ebay to keep my nexus 4 snug.

[DeepThought]

I has a go at this a few weeks back but couldn't get the alignment right. I think the magnetic field of the meter long steel tube of my scope wasn't helping to be honest.

I would align on one object, point to another and align to that too, then go back to the original alignment point and find it to be wildly inaccurate. Even with a few inches gap between the scope and the phone it still wasn't playing ball.

It might be useful as a rough guide, but I certainly wouldn't set my watch by it.

If you're lucky/affluent enough to have a scope that doesn't have a steel tube then my lightly modded joggers armband phone holder held it pretty securely.

See here

Was using a Galaxy S2 by the way.

[Eastridge]

I'm interested in trying this soon as well. I'm wondering whether plonking the phone on top of the telrad might be enough of a gap - if so I could probably rig something up with one of the cheap car mounts from ebay to keep my nexus 4 snug.

If I recall correctly some people have tried on top of the Telrad, the developer of SKeye's site does warn that whilst that keeps it away from the steel tube the magnetic fields created by the battery and wires in the Telrad body itself may cause interference but as we seem to have clear evidence of different phones having different levels of susecpability to such fields I'd say give it a try with your phhone and see.

[Eastridge]

I has a go at this a few weeks back but couldn't get the alignment right. I think the magnetic field of the meter long steel tube of my scope wasn't helping to be honest.

I would align on one object, point to another and align to that too, then go back to the original alignment point and find it to be wildly inaccurate. Even with a few inches gap between the scope and the phone it still wasn't playing ball.

It might be useful as a rough guide, but I certainly wouldn't set my watch by it.

If you're lucky/affluent enough to have a scope that doesn't have a steel tube then my lightly modded joggers armband phone holder held it pretty securely.

See here

Was using a Galaxy S2 by the way.

We clearly have vastly differing experiences of trying this and both are valid. I belive that my Dob has a greater length and volume of steel tube than yours does so the problem would seem to be more complex than just saying 'it won't work if you have a steel tube' .

From the research I have done the variables are:

- different phones have different levels of sensitivity to magnetic interference

- each tube can give off different levels of magnetic interference, this isn''t 'model to model' but between individual scopes due to their history etc.

So first step should always be to hold your phone by your scope , do the 'figure of 8' step on the SKeye website and see if you get warnings and strange behaviours , if not try a quick rig, taking into account the steps recommended on the Skeye site to minimise disruption as next step and if it works OK consider it as a permanant finding solution.

[DeepThought]

We clearly have vastly differing experiences of trying this and both are valid. I belive that my Dob has a greater length and volume of steel tube than yours does so the problem would seem to be more complex than just saying 'it won't work if you have a steel tube' .

From the research I have done the variables are:

- different phones have different levels of sensitivity to magnetic interference

- each tube can give off different levels of magnetic interference, this isn''t 'model to model' but between individual scopes due to their history etc.

So first step should always be to hold your phone by your scope , do the 'figure of 8' step on the SKeye website and see if you get warnings and strange behaviours , if not try a quick rig, taking into account the steps recommended on the Skeye site to minimise disruption as next step and if it works OK consider it as a permanant finding solution.

Oh don't get me wrong, I certainly think it's still worth trying, and indeed I haven't given up on this myself yet.

To put things in perspective, a push-to upgrade for my dob would cost me hundreds, give me a free app for a phone I already own and a 3 quid home-made holder over that any day.

My phone is due an upgrade at the end of this month and frankly I've always disputed the accuracy of the compass and inclinometer in my current model anyway.

I will report back when I have had tested on different equipment.

[Eastridge]

Understood DeepThought, I just wouldn't want anyone to be out off trying it by misunderstanding your post- as you say if it works it can save £100's, so worth a try even if it won't work for everyone.

[nicks90]

Depends also if you have an android phone and like to flash custom ROMs! Some of the ROMs I've tried on my Motorola atrix have given me hilarious GPS/accelerometer results, others have been vastly better than stock! its all down to the kernel and drivers - as well as the actual bits of hardware inside the box.

I think with this method of push-to, its really a case of suck it and see as there are just too many variables - scope magnetism, hardware, internal shielding, software, mounting option etc

[astronymonkey]

Hi Eastridge,

Many thanks for posting this mini-review, Ive got this app downloaded on my phone but havet had chance to road test it yet.

Is there an option to preprogram a "tour" into the app to allow you to go from one object to another , and do you select the object then it tell you to push left/right or up/down to get to it or do you need to know where the object is and then just align it on the phones screen ?

cheers,

Astronymonkey

[DeepThought]

Hi Eastridge,

Many thanks for posting this mini-review, Ive got this app downloaded on my phone but havet had chance to road test it yet.

Is there an option to preprogram a "tour" into the app to allow you to go from one object to another , and do you select the object then it tell you to push left/right or up/down to get to it or do you need to know where the object is and then just align it on the phones screen ?

cheers,

Astronymonkey

I've not seen an option for a "tour", I just found for an object using the app's search function and then you follow the arrows on the screen with your scope to find it.

Very nice interface for a free app, It's a shame there aren't more out there like it for Android.

You can download a user guide here.

[astronymonkey]

Thanks Eastridge,

I have a friend who has an I-Phone and hes disappointed that this app isnt on the i-tunes store which makes a change !

I think its a great ap and I wonder how long it will be before there is an after-market retrofit unit based on this idea (a bit like a sat nav) from at least one of the big manufacturers.

CHeers,

Astroymokey

[jason.p]

I made this gizmo to attach my Galaxy Tab to the OTA out of some old aluminium window frames. It clamps round a band of non slip mat which I put on to help grip the tube to turn it for different orientations. There is enough slip to move the tablet round to suit. No idea if it's going to work, haven't had a clear sky yet. I've downloaded Skeye, Google Sky Map and Stellariun.

Thanks for info Eastridge

[daz]

Very interesting thread!

I have a Nexus 4 on its way and this would be great to use at society/public outreach events!

Subscribed!!

[astronymonkey]

The great thing with SKEye is that you can align it offset from the device. In the neat set up Jason has above the scope and screen are aligned so as you look along the length of the tube then the view is show on the screen, you can however mount the device in any orientation on the tube and then drag the screen image to show what is actually in the field of view and then set this off axis alignment. As long as the device moves with the scope then the device will still display the correct field.

Difficult to explain but basically you could have the device on the ota, side by side, with the eyepiece and still have it show the right piece of the sky. The program even gives a warning if the magnetic fields from the tube are causing a problem with the internal compass , and this is one of the reasons Im steering clear of a magnetic counterbalance system for the ota over a one which is mechanically fixed.

Cheers,

Astronymonkey