Ok, the sledghammer almost came out last night...Help !

[jbdave]

I am getting frustrated. So very frustrated.

I set up an 8 inch newt in the backyard of my old house, and took some decent images., albeit with only 20-30 seconds. I am guessing my polar alignment was a fluke more than anything.

Fast forward a few months and I have moved house. Now no matter what I do, I cannot get an image of 20+ seconds without star trails. 8"newt fail, ED80 fail. Nothing.

For the past few days I have been screwing around with everything and anything. Here is my procedure:

1. Set up tripod with compass directing true south.
2. Level tripod
3. Fix mount to tripod. Use clinometer to get approx latitude.
4. Attach telescope and balance everything.
5. drift align for a bit, and notice stars don't really move off line
6. Try and take photo and remove camera after trails are evident
7. Try the DARV method and with 1 min exposures showing nice clean lines with no movement (I know not long but I am only after 30 seconds exposures here for photography).
8. Try another shot. Trails again.
9. Punch fence, and walk inside to get a drink.
10. Come back out with laptop, guide camera and all the cables i hate setting up.
11. Run PHD, and undertake drift align. Get pissed when EQMOD stops tracking at random for some unknown reason.
12. Monitor tracking and make sure it stays on. Get that stupid line pretty straight, albeit slightly up and down but within 1 arc minute. Then I run it again where the line appears to do what it wants (and I'm making sure I am not tracking on a hot pixel).
13. Run it about 390 more times to make sure I was not seeing things. Confirmation that I wasn't seeing things. The line isn't consistent.
14. Try to take another shot as it's getting late and I'm cold and frustrated. Guiding is on via PHD.
15. Scream when guiding does **** and I was doing better without it.
16. Take another photo just to make sure the astro fairy hasn't magically set up my scope properly in between steps 14 and 16.
17. Pack up scope and cover up mount. Go to bed trying not to wake the wife and kids and I stomp down the hallway like a 3 year old throwing a tantrum.
18. Wake up and post on Ice In Space so I can get advice and go screw it up all over again tonight.....you know, when the clouds roll in.


So there you have it. I guess my imaging at my old place was more of a fluke than anything as I was quite happy with some of the images.
Could my mount be an issue ?
Does it need a service or a tip run ?
Am I meant to be going loopy ?

Sorry for the long post, but I am about to throw it all in, and I'm not going to continue a hobby where it takes me 3 days to set up in a new location...

PS: I am heading off out bush for the weekend. I was considering taking the scope, but am concerned it may end up getting thrown in the Murray River. Thanks in advance for any assistance.

[jbdave]

FYI - I am using an ED80 with an 80mm guidescope attached on a HEQ5 Pro mount.

I also have an 8" newt that I use, without guidscope.

[xelasnave]

I seem to be going thru a similar frustration so lets blame the gear☺
I drift align and all seems good and I also take time exposures with mount stationary and the scope in home position and I line up to have the center in the middle of the camera viewing frame...this has always worked for me but not now...
One thing I am thinking is the level bubble is somehow off as it shows level but standing back and looking at the mount it does not seem level so I am today looking for a spirit level to provide a better measure.
I have even thought the ground could be subsiding and maybe this is close to the truth in so far as the mount is on some paver bricks placed on the lawn and maybe the grass is still compacting and there is movement in that area.

Also make sure all adjustment knobs are snug and when adjustment complete make sure its opposite is seated so nothing can move.

In any event stay calm and know you are not the only one having such frustrations.
Anyways if 30 shows trails go down to 20 seconds and if thats too long drip again.
One positive from such an approach was I got to do short exposure and high iso that turned out very well....so you can bet when we find we dont need polar to be perfect it will some how become cured:P
Good luck.
Alex

[Imme]

EQMOD stops tracking for some reason......Do you have "mount limits' enabled in the EQMOD menu? If that's a yes I'd guess that's the issue with the tracking stopping, I had the same problem.

You're obviously running a laptop.....if possible try and get a copy of Sharpcap and use their polar align tool (if you can get version 2.9 it's free). I faced the same issues as you with PA until I used Sharpcap.....with it I can get within seconds of the pole in less than 10 minutes

[astro_nutt]

Hi David. Been there done that, but I have learned a few things about mounts so....
Sometimes I set up everything in my room during the day, and let it run, then check to see HOW it performs. Mostly, I find constant power supply to be the culprit. I check it by plugging in a lamp and watch to see it dulls n the fridge kicks in. Next is the mount itself, check for any stiction, stiffness, backlash, etc. Do you have enough weight bias on the drive so the drive is "pushing' the scope. Next is the scope. Focuser slack, primary, secondary mirrors loose. Last is the tripod. Nice and tight, pegged into the ground, etc.
Hope this helps.
Cheers!

[John5]

Hi David et al,
Being in the middle of my own learning curve, I can really empathize with you!!

You mention using a compass to find South. I eventually decided that I did not trust cheap compasses or down loaded apps, but finally used the vertical rod and ' sun at the zenith' method to mark out a true north-south line where I set up. A good spirit level and plumb bob is used to set the tripod up. Simple and effective. A good inclinometer app. makes sure the altitude setting is OK.From that point Sharpcap takes over though that is still in the learning phase atm.

Re power supplies, I do not know how sensitive the HEQ5 is to power fluctuations or how you power your mount. If you have a mains power supply and are in a rural area or have such things as a pressure pump/ pool pump that cycles on and off the mains voltage can vary (as per astro_nut's post). I use a jump starter unit from that cheap auto place to power my mount. Works fine and I can use it portable if I wish. It also has a 5v outlet for those usb powered things.

John5

[Wavytone]

Not properly polar aligned. Drift aligning has always struck me as a fudge, frankly, though some do manage to get it right.

I’ll suggest you buy a device such as the QHY Polemaster so that you will be able to align the mount with total certainty in future. Or insert a laser pointer in the polar axis to see where it’s actually pointing vs the location of the SCP.

[AstroBogan]

I had similar issues.. i'm not expert at all infact I am a beginner myself.I'm not sure if it is gear related or what for you, but for me, i bit the bullet and got myself a polemaster and I can polar align in literally 2 minutes when facing my mount in a general south direction given to me by my cheap compass. without guiding I can take up to 120 second exposures without star trail with my ED80. Before making this purchase, for months I was struggling with PA but now I couldn't think of not having the polemaster.

Not sure if the pole is obstructed for you, which would leave the polemaster out of question, but if not, I highly recommend investing in it as it has saved me countless hours.

[xelasnave]

How does Polemaster work or rather does it have its own program and shows a target on screen?
Alex

[xelasnave]

Dont worry I found all I needed on utube.
Alex

[AstroBogan]

Yeah everything you need is on youtube, but yeah all you need to do is identify sigma octantis on screen and the stars surrounding it to fit the outline on the screen and just follow the prompts for an extremely accurate alignment. It is pricey, but honestly, the money spent is worth it for the time saved.

[xelasnave]

I have been thinking about this...my method of capturing star trails is really the same in principle...all I need check is that the polar scope and the mounted scope point at the same spot , again as maybe something has changed, but next time I will use the enlargement feature to examine my star trails, as in reflection I could be more precise.
It should work and I can save some cash even if it may take a little longer.
Really it should be more precise as you are working with a larger scope...anyways the rain has set in for a week an a half which takes us to more Moonlight than one would like.
Alex

[Scorpius]

Throw away all ya guidance systems and fancy software tools. Go back to basics. Been ages since I popped up on here, but my method which has worked now for many years:
Using a reasonable GPS and find the real True North and mark the main compass points on your patio/area floor. Most Equatorial Mounts have a calibrated scale. Set it to your correct location on Earth, confirm with a certified engineers inclometer. You now have your scope positioning settings. (I have never used Octans nor the built in prisms because that area of the sky is blocked by my house - I live in a small home unit with no real estate)
One essential tool is a laser guided collmination tool they are cheap, because you can be rest assured your collmination shifts every time to mount/unmount your scope.
Initially set up your scope accurately paying attention to date/time. Always start from the PARK position and do a minimum of 2 star alignment.
If you have an EQ6Pro Mount by Skywatcher, select a subject from the menu, if you have done all the aforegoing, you should be within cooee of the subject when you "goto"
Another very useful device is the latest red dot (LED) finders, they are designed like a rifle scope thus you can see "outside" the viewing ring. Something you cannot do using "scope" type finder. I replaced all of mine.

Right you're looking at Saturn or Jupiter now sitting dead centre in your plossl - What's the issue now? Out of focus? well just focus, unless you have a load of faulty equipment there should be no issues.

When all else fails go back to basics. Even check out your scope in daylight, focusing on a terrestrial subject. (WARNING Never allow the scope to go anywhere near the position of the sun without certified filters installed - Failing that keep the cap on scope).

Many years ago I started the hard way, building my own DOB from old 2nd hand parts, that and my other stuff is on my web page (Down at the moment, need to port forward as we have just had NBN connected - I leave that sort of stuff to my son!)

One Question? What method are you using to take photos? Essentially you should be using a DSLR in Prime focus. Camera etc?? (Prime focus is when you use the scopes optics and no lens on the camera).
I am happy to discuss things via PM. Also an ex Member of ASWA.

G'Day to the old timers I knew :) Am now approaching 83. :)

[xelasnave]

Hi Dave
Wonderful to hear from you and thank you for all your advice.
However I changed tack and just now ordered one of these polemasters cameras.
It is the first thing I have ever purchased on the net which I did via pay pal.
Probably not good that I have learnt to do this as I have a feeling I could go on a buying spree...
Hope you get your web site up again.
My equipment is..80 mm triplet and a f5 eight inch reflector and a permanent eq6 mount in Sydney and a HEQ5 which I bring up North to Tabulam a nice dark location ...I use a Nikon DSLR camera model D5500 which has 24 meg.
Due to not dialing in a decent polar align I have been capturing objects using 30 second exposures mostly at 1600 iso.
I suppose I should have asked this first but were you asking me about what gear I used or were you asking David the author of the original post in this thread?
Alex

[John5]

Thank you Dave.

Although I am a real newbie I think my method echoes yours. I tried the cheapo compass, the compass app. on the wally-phone and the dodgy altitude scale on the HEQ5, the unfathomable/ unuseable polar scope and a professional GPS unit. Finally, a combination of the basics and a couple of modern tools ( Sharpcap and an inclonometer app) along with a simple spirit level and plumbob gave me success.

No wonder we newbies tie ourselves in knots. There is so much info out there that it is both a good and bad thing - I believe that in many endeavors we do need to remember basic principles and let our learning grow from there. However, modern tools are fine to use if we remember they are just that - tools. We still need the understanding of their use.

John5

[redbeard]

When setting up, a compass will only get you close to be polar aligned as you know.

What method are you using to adjust the mount to align more tightly?
I ask as you mention drift align, but you have not mentioned what you do to fine tune things. Are you actually adjusting the mount manually, (not with the hand controller etc), to get closer polar alignment, or are you using some other method?

I'm sure between all of us, you'll get the help you need.

Cheers,

Damien.

[raymo]

If you are following the DARV instructions to the letter, and the stars return
accurately along their original lines for 30 secs, when using an ED80 at prime focus, then your problem is unlikely to be poor polar alignment. To narrow down the possibilities take some very short exposures and see when trailing appears.
If it appears almost immediately, say after 6 or 7 seconds, then its definitely not a PA problem.
Firstly, don't balance the scope precisely; balance it a bit against the drive to eliminate any gear backlash, and try an exposure.
Secondly, do some exposures, say 15-30-45-60secs. Does the trailing in
the 30-45 and 60 subs equal approximately 2x-3x and 4x the trailing in the 15sec sub, or does nearly all of the trailing happen during the first 10 sec sub? If the latter, then it would seem that there is some slop somewhere in the drive train. That's a couple of things to check to start with, good luck.
raymo

[Scorpius]

Hi Alex, good to 'see ya' agn! Mainly my post was directed to David, he with the sledgehammer.. I think we have all been through issues with Astronomy and things not going right, I was no exception back in 2005 when I became interested in Astronomy. Initially I was interested in the engineering side of things and making my own equipment and did many experiments, luckily having a friend who had a professional CNC mill, who did some very fine work modifying focusers etc. Hopefully my son will be up soon and fix my router and you will be able to see my Astro page and the many other hobbies I have been involved in.

I will elaborate on a few things, but basically my advice to all new comers is to Buy, Steal, Borrow as many books as you get away with, visit your library, subscribe to a Magazine or even join a local Astro club.

As members have said there is a wealth of information on line which is free and readily available. Get a good grasp of the basics and what terms mean, they will answer many of your questions.

Seeing Just as it says, how well you can see the subject, if the 'seeing' is bad, then the best scope in the world will not fix it. This is the condition of the atmosphere, which around the world is deteriorating at a rapid rate. My colleague Ray Palmer, who runs "My Astro Space Astronomy" website, has said that in Western Australia, conditions have been so bad he has not even attempted to take any Deep Sky photos. Myself out of interest purchased from EBay one of those $50 mini gold cams that plug into the focuser and connected it to a 10" monitor. This cam has a huge magnification factor and took both stills and a movie of a section of the moon. It was shocking it was like looking through a flowing stream of water, with the section of the moon bouncing around. The results are published on the MASA forum site.
So, if your seeing is not good and in general reports from Eastern States of Australia and from the UK are that over the past 12 months it has not been good. WA has suffered from continuous cloud forming offshore and drifting over land for many months -- Most un-nice!.

Compasses I almost cringe when I hear people using a compass, be it a an el cheapo from China or Certified Ships compass. No matter where you are they do not point True North! They are affected by surrounding metalic things like sheds, cars even the very scope and mount you are using. Also they are affected by the very earth's magnetism known as 'deviation' this changes for every part of the world and Navigators of old had to have correction charts to make adjustments. GPS is the only way to accurately find True North. As is said mark the Cardinal points on the ground at home where you set up your mount.

Calibration Unless you calibrate and ensure your mount is correctly positioned, you are wasting your time. Pages have been written on the subject, learn the theory and how it works, then you will understand how accurate position, timing etc affects the results of your observations and photos. This is why it is handy to have a laptop/tablet/mobile phone to receive an accurate time standard.
I guide my EQ6PRO using a Dell 1500 series laptop and Stellarium, I can use it in 'actual' or simulation mode and works very well. Recently after being inactive for quite some time I setup my 10" dob on the EQ6 and for a while I could not work out why the scope was going in the wrong direction and trying to wrap itself around the legs of the mount!! Then I recalled before I put it in storage I had cleaned the electronics board, greased the gears. I had also reversed the plugs to the stepper motors ALT and AZ. (They now have labels on the plugs!)

Drift Alignment Requires a special plossl with illuminated cross hatch of an LED. The principal is to measure the amount of movement of a subject within the centre of the crosshatch and make compensation of the physical settings of the scope. It is a refinement of 2 or 3 star alignment, It is a complex subject and one should refer to sources on line as to its full application.

When all else fails Remember even NASA got it all horribly wrong in the initial stages of the Hubble Telescope, costing millions to fix. So have faith in yourself and your scope. Its fine to have guidance systems and accessories, but first make sure the basic functions work first and add slowly any new improvements.

A final comment when using a Digital Camera try and avoid jacking up the ISO. 100 to 400 is fine - The bigger the ISO number the greater the deterioration of quality, it works on the same principle as film a low ASA gives you a finer grain. With an accurately guided scope you will not end up with images of stars looking like Comets!

Astronomy is a fascinating hobby, it can also be a very frustrating one and the learning curve is steep. Read, and read again, practice in daylight in setting up your equipment and using it, including taking photos of trees and subjects some distance away. If it bothers you taking photos upside down use an erecting plossl - Clear skies:)

Dave

[jbdave]

Thanks for all the advice.
I am going to get out again tonight (weather permitting) and try a few things.

I'll report back !

[Startrek]

Hi Dave,

I'm only 18 months into the hobby

Most times I get within 1 arc minute of PA which allows me to take at least 60 to 90 second exposures without star trails

I dont use a PC with guiding software or a guide scope etc.. old school

My kit - 150mm F6 reflector OTA
HEQ5 mount with Synscan
Canon 600D unmodified
Orion 20mm 70deg illuminated reticle eye piece used for alignment

PA Method

Forget compasses waist of time IMO , I use Stellarium software to find the noon meridian (time where sun is directly overhead and in line with SCP )

Level a 1m long x 12mm diameter piece of timber dowel at 90deg to the ground , driveway or paved area ( use string and weights as guy ropes to anchor the timber dowel at 90deg )

At exactly noon meridian time mark the shadow cast by the timber dowel at base of timber dowel and 500mm out along shadow ( line to be exactly in centre line of shadow ) This line will give you True South ( closer than any compass magnetic declination method - provided you are accurate with levelling and marking )

I set up my tripod mount along this line using a plumb bob and piece of aluminium angle ( once again as accurately as you can)

Level your mount

Set your latitiude ( I use a quality digital inclinometer ,not the crappy scale on the mount )

Balance your scope

Carry out a 2 star alignment as per Synscan manual ( use 2 stars same side of meridian not to far apart ) I used Hadar and Acrux last night

Then carry out a Polar alignment using method in Synscan manual section 11.3 page 36

Repeat 2 star alignment and polar alignment at least 2 or 3 times

You will get close to PA

Remember when using the Synscan to finish with the Up then Right direction keys when centering your stars

Also with the Orion 20mm illuminated reticle eye piece make sure you keep your head relaxed and still to ensure accurate alignment each time in the centre of FOV. I have astigmatism in my right eye so I use my left eye for star centering

I did struggle for months but take your time and be as accurate as you can and Im sure it will all work out for you

Best of Luck

Martin

[Scorpius]

Well done Martin, throughout my whole life, I have always followed my father's advice, "To achieve what you set out to do, first you have to learn to walk before you try to run" This applies to everything. I do not think I have fallen far below that mark in becoming an Expert in my various ventures.

However to become an Expert, you have to qualify in the following parameters: "X" the unknown factor "Spurt" A drip under pressure :rofl:

Basically that means you have to be slightly crazy! :)

[Scorpius]

My web page is back on line Check out http://dsmithdale.net/ and select Astronomy Page. Still working on the pages so some links may be a bit hairy :)
Cheers
Dave

[jbdave]

Just thought I would post an update.

I set up the HEQ5 mount in the country up at my in-laws place with the ED80 on top. Tried a few different methods. PHD2 was all over the place and I couldn't get it consistent. Drift aligning was taking me half the night. I then tried Sharpcap as per a suggestion above.

I ended up getting 1 minute exposures without trails, which I was pretty happy with. I wasn't overly happy with the images due to focus issues, etc through the ED80 (will be buying a mask to help with that). The weather also wasn't the best so I didn't get any great images out of the night, but it did allow me to experiment.

I then went and bought an AZ-EQ6 to set up at home as I prefer imaging with my 8" newt, and with the guide scope/camera set up it was getting too heavy for the HEQ5.

A couple of nights in and I am up to about 20-25 second exposures. Guiding gets me about another 10 seconds, so clearly I am still off somewhere. The polar alignment tool in sharpcap changes when I re-do it and swing the scope 90 degrees in the other direction. I do know I am still a little off however, but at least it's getting me something. I am also working with a 1000mm focal length, rather than the smaller ED80.

These are two images I took a couple nights back with the ED80 and the 8"newt.
Now my problem is colour issues in post processing, which can be seen in another thread :)

[Rigel003]

Nice photos. Regarding the time taken for polar alignment, I'd second the advice given by some others. Buy a Polemaster with an adapter for your EQ6. It costs a bit but it's such a time saver - quite revolutionary. I find it easier to use than the Sharpcap routine, and absolutely perfect alignment every time in less than 5 minutes. You'll have no trouble with 10 minute or longer exposures and guiding software will respond better. Highly recommended.

[VPAstro]

I also agree with the polemaster. Probably one of the best pieces of equipment I have for aiding in quick setup. What use to take me 30 - 60 minutes to do with 2 star alignments, and polar align functions, and repeating it until I got as close as possible, I now do in 2 - 3 minutes. Total setup and alignment takes no longer than 15 minutes.
Now I have the issue of frost, and the 90 minutes or so that it takes to clear from the ccd sensor before I can start imaging....bummer

[sil]

Accuracy accuracy accuracy. Do it slow and do it correctly and above all else, accurately. Do NOT buy measuring tools from ebay. Do not waste time on apps, phones are NOT calibrated measuing equipment.

For my CGEM-DX I used a plumb bob and accurate timepiece to line out N-S line at solar noon. Confirmable/repeatable over several days. No approximate markings or eyeballing or dodgy compasses used or needed. Masking tape, fine point sharpie, fine line string and weight and old camera tripod to dangle it from.

My celestron tripod allowed me to lock one side set of adjustment knobs leaving the other side free to fix with. This meant I could put the mount on top and get it N-S aligned accurately and permanently lock off one set of adjusters, using the other set to hold the mount in place. This allowed me to take the mount on and off repeatedly in the dark and it would be NS aligned. My ground was paved and likewise I used a masonry drill bit to drill three small pits the points of the tripod feet would seat themselves in comfortably. I was able to borrow a calibrated digital level to set the mount dovetail to my latitude as best as I could. With everything set up I was then able to put a piece of masking tape across the rotating joins, draw a fine black line across and cut with the join gap using a razor. This gave me parking marks to put the mount in for my "home" position and it would be pointing at SCP. at night i would periodically set up with just a dovetail mounted camera and take test long exposure shots. It was always obvious the camera at this "home" position was showing the SCP close to center of frame for my needs just above my roofline.

This process didn't take too long to work out, a couple of days to ensure I had a good NS line drawn on the ground and up the wall, confirmed over several days at solar noon. Then later when it was in place I could use a strong torch and plumb line rigged in my yard to cast a shade along the marked line and use that to help align and center my tripod etc. I later used a wax crayon to go over the line so it would be there for future use and wouldn't wash away.

It took me a bunch of nights to drag everything out and take a long untracked exposure to ensure scp was in middle of my camera sensor and Then I felt I could trust my routine was repeatedably alignable. And every few months I would double check when I was gearing up for a season target.

From there the only thing I had to worry about was balancing. I found it best to put all the gear on and slew it to where my target was going to be for imaging and then balance it carefully at that point. I could do my multistar alignment for the goto, btw this is all with just the mounts goto handset, no guiding camera or laptop control. The star alignment would look off as the rig would be slightly off balance pointed at anything other than my target. But once the alignment process was complete and I slewed to my target it would be dead center and stay there without drifting for the shooting time I needed at least.

Another gotcha though is the handset itself, first dont pull it far from the scope as it may be putting tension against the mount motors which can reduce alignment and tracking accuracy. Make sure the cable is very slack and wont catch on anything as the mount moves during the imaging session. Secondly is when you use the arrow keys to slew to a target often two of the direction keys will hold position when you release them while the opposite direction keys may contune to slew and even drift. I think this is due to the meshing tolerance of the gears themselves but not certain. Its easy to see when slewing to a planet or the moon. Test getting a target in center of view where your final button press/release is say the up arrow. Watch for the drift, repeat with the down arrow as the final press and watch for drift again. Sometimes there is a little extra slewing that comes to a stop and remains steady. Just observe what your gear does. repeat for left and right arrows too. I don't know if it changes depending on where the scope is pointing so it might change? Its something I keep in mind anyway and test quickly each time I image where I may need to manually adjust with the handset. Its very little bother to just check when setting up before imaging, especially shorter planetary sessions.

I know a few of these were touched on by others, but maybe some of what I've outlined can help too.


Accuracy and lots of patience and do testing too, I find all this is needed . Take your time, plan your goals for the session, eg testing settings only. and stick to the plan. Don't get distracted by that bright object over there and not get what you need to achieve your goal for the night, take note of it to make it your goal the following night instead. Especially when learning and trying new gear its easy to get distracted and sidetracked with other targets.