almcl

1 hour ago, Grant93 said:

 But arent the text files created when stacking in DSS anyhow?

Yes they are, but if you stack one night's data and then add another, later set, with a different rotation and  displacement DSS gets confused and produces the double star result,  DSS won't necessarily recalculate the registration settings unless the appropriate box is checked.

I *think* the double star issue at the top of the frame might go away if you delete all the text files in the folders which contain your lights for DSS and then try re-stacking.

I have had a go at your data using StarTools and agree with KP82 above: there's very little Ha signal.  Unfortunately there's also quite a lot of light pollution and a gradient which on a very quick run through I didn't eliminate.

Here's what came out:

Has anyone replaced the polar scope LED on an AZEQ6?

Mine seems to have stopped working.  Changing brightness levels via the hand controller doesn't make any difference and there is voltage as far as the pins on the LED itself (not much, 1.9 v) but, unhappily, no illumination.

In truth it's not a huge issue as I almost always polar align before the end of civil twilight when the reticule is visible against the sky, but just occasionally (last night, for instance) I need to align during astro dark and although shining a torch down the recess sort of works, it would be nice to have the 'official' rather dimmer light source in play.

I have a box of assorted LEDs which could probably supply a suitable replacement, but only if the carrier can be removed from the polar scope tube.

I did have a go at this a while back as a widefield Ha target using an Astronomik 12nm filter on a Canon 700d.  Maybe I should revisit it with the Lenhance and the ASI 2600

Did you install the latest ASCOM platform first?  

https://ascom-standards.org/Downloads/Index.htm

Is there a reason you don't want to use the Starlight Express ASCOM driver?

http://www.daddog.com/ascom/sxcamera

On the APT forum Yoddha states that there are no reports of any problems with the SX cameras https://aptforum.com/phpbb/viewtopic.php?f=12&t=2470&p=15268&hilit=starlight+express#p15268

This may not be the issue at all, but check to see which Com port the AZ EQ6 is being assigned to when it is plugged in.  Is it the same one as the HEQ5? 

I *think* Windows recognizes the cable rather than the mount, so it should be the same, but worth a check? 

Here's a screen shot from the free software Stellarium showing what should be visible to the south from Kolkata at around midnight. Nearly all the objects are south of the celestial equator.  

If you want to capture images of these, the best time is as they cross the meridian (green line in the image) as they are highest then and there is less atmosphere to spoil the view.

I will buck the trend of advice here, slightly and say that I have a SW 200p and EQ5 mount and used it quite happily for visual and, once I had added motors to it, for Astro-photography with a DSLR.  True, not all my images worked, but quite a few did and I was quite pleased with the results. After a few years I did upgrade to a better mount and more recently to a different scope and finally to a dedicated Astro camera, but I definitely don't regret the EQ5's purchase (I bought new when prices were a bit lower than they are now) and still use the EQ5 mount when imaging with a Canon 200mm lens, for which is more than adequate.

Think there are several, but does this one help?  You need to translate the 100% illuminated circle figure (on the specs tab) to whichever APS-C sized sensor dimensions  you're using, but otherwise it seems to work

https://stellafane.org/tm/newt-web/newt-web.html

When I experienced this problem it was down to differential flexure.  Never did establish exactly where this was occurring - could have been mirror flop, focuser sag on the guide scope, something else entirely or a combination of all three. 

As to why yours manifests only when imaging, that is a puzzle.

Mine was cured when I moved from a guide scope to an OAG but I was already guiding (only on a Skywatcher EQ5 to which I had added stepper motors) so can't promise that guiding without an OAG will cure it but there's a good chance an OAG will make a difference.

Not quite sure what the statistics mean in terms of adjustment.

Having spent an interesting hour or so adjusting the tilt plate on my asi 2600 while it was on the scope, I managed to completely reverse a corner  tilt of similar magnitude with about a half turn of the adjuster. May have to resort to feeler gauges to assess the amount of movement necessary.

Don't have PI or CCDI, so ran the three through ASTAP's CCD Inspector function and got these.  First and last definitely look like tilt, but the middle one doesn't seem nearly as far out.  Not sure if this helps? 

I wonder if the increasing levels of light pollution in towns and suburbs has an effect on this?

I started imaging because all but the brightest DSOs are invisible from my back garden.  Even mighty Andromeda is just a small, faint grey blob.   With an image I can now see galaxies (my maIn interest) that are completely invisible, even if I pack all the gear into the car and drive the 40 minutes to a dark sky site.  

For those who live away from LED street lights, neighbour's insecurity lights and white painted houses reflecting large amounts of the same, visual must be very satisfying but in my hideously light polluted town, it's more than frustrating.

One slightly bizarre approach I used was to attach a tarpaulin to the uprights of my grandkids' trampoline and use this a shade:

2 hours ago, martinclayden said:

I'm a bit confused about your second statement though; "as close to the pole as possible" - means Polar aligned I think ? If so, what's the relationship between "home position" and PA ?

Polar Alignment is the act of pointing the mount's RA axis at the celestial pole.  This can be done without the telescope being on the mount and for purely visual use 'near enough' is quite sufficient to keep an object in view while the scope tracks.  This doesn't, however, mean that the scope will be pointing at the pole, a small displacement in either axis (which won't affect or be affected by PA at all) means that the first goto will be off, by at least as much as the scope was off from pointing at the pole.  There are other errors that can affect this, but the scope not pointing exactly at the pole when in the home position is quite a common one.

Hope that makes sense? 

There are two aspects to this.

First, daylight saving time or British Summer Time is in force at the moment, so your  DST should be "yes".  That may take out some of the error but possibly not all of it.

The second part is how accurately the home position is pointing at the pole. PA doesn't affect this, you need to make sure you are as close to the pole as possible looking through the eyepiece or finder when initialising the mount if you want the first goto to be accurate.

Thanks, Wim!

On 27/06/2021 at 17:28, wimvb said:

 Also, you shouldn't move the secondary mirror up or down the tube.

Do you know why this is so critical @wimvb ?  (Not arguing, just seeking enlightenment.)  I only noticed the focuser on my 190MN came with slots to allow it to be adjusted up or down the tube after I had moved the 2ndry down a bit...

And for the OP, you may find this thread (and some of the links others posted) helpful:

Don't have personal experience but you might want to have a look at this thread:

1 hour ago, StuartT said:

I wonder if anyone has any thoughts about how long I can go with subs (I am not guiding) with this 400mm lens? 

Maybe that's something to try while the light nights are with us?  I managed 3 minutes unguided with my 200 mm lens, so you might well be able to get past 60 sec.  Of course the seeing, polar alignment, target altitude &c will all have  a bearing, but certainly worth experimenting to see.

Had a play with your data and agree with what has been said above: it's very nice!

Here's a crop of the central area just to show the detail that is present, well done! You can probably achieve something similar in APP?

Unfortunately most galaxies are fairly dim objects.  Even mighty Andromeda (M31) is little more than a central blur from an urban or suburban location.  All the usual advice applies, dark adaptation, not using phone, tablet or laptop screens so as to preserve night vision, use averted vision, scan the area, don't hold your breath, I have even resorted to 'black towel over the head' to help cut out street light pollution on occasions

If you can get to a dark sky site, the situation gets better.  Unfortunately, we are just about to loose astro darkness (which does make a difference) but before we do, and if you haven't already, try M81 and M82.  They are almost overhead now as Astronomical darkness falls and are reasonably small and bright.

What galaxies were you trying for?

Couple of other points which I don't think anyone has mentioned.

Once you calibrate and before moving to target, carry out a guiding assistant run and accept its recommendations.  This will account for changes in seeing and may make other suggestions.  I can't see one in your log file?

Second, and this may not be what you want to hear, but you appear to be imaging at around 0.5" per pixel (making assumptions about your DSLR and scope)  but guiding at over 6 " per pixel, a ratio of 12 to 1.  This is likely to be problematic, even if you can get the guiding down to a tenth of a pixel - which PHD developers suggest is the likely limit of possible accuracy.  In the fullness of time you may need to consider an Off Axis Guider, although that too will not be without its challenges.

Can't you loosen the scope rings and slide the OTA down a bit?