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04Stefan07
13-04-2014, 11:16 PM
Took out the MAK 127 SLT since it's a clear night tonight. A few issues though (just like with my other scope when i started out haha).

1) Tracking! Arghhh. Time (U.S. format), time zone, daylight savings/standard time, location, etc all were correct. Once I align an object it will start to drift slowly out of view. Is there something I am doing wrong? I am using a NexStar Plus controller. In the menu under tracking there were options such as EQ South, Alt, Sidereal/Lunar tracking, etc. What would be the correct settings and if someone could guide me through the settings on the NexStar plus?
Could the tracking problem relate to the weight of the OTA? It is a lot heavier than the 130SLT but they both use the same mount so it should be able to handle the extra weight.
2) I did adapt an electronic focuser to this telescope today (there is a thread about it). It worked alright but not too well so I have taken it off for now and want to add gears instead of a rubber band which should focus more accurately.
I used the normal focus knob but it seemed when I got the Moon into focus it didn't look crisp or it went out of focus and I had to readjust. I am not sure if it was me being frustrated or actually happening??? I hope the focuser isn't broken.
3) Jupiter just looked like a big bright dot. With a focal length of 1,500 mm I thought I would see some detail. Is this due to the Moon's light reducing detail in Jupiter??? Could it also be dew forming on my telescope as well??

I know buying a proper EQ mount would solve some issues but it's an investment I can't afford at the moment. Definitely in future though! Once I sort these problems out then I should be back on par like I was with my 130SLT.

Thanks!

Renato1
14-04-2014, 12:34 AM
With respect to the images in your Mak.

1. Check the obvious first. It's a cold night, make sure you aren't looking over someone's chimney. Are the stars twinkling a lot in the area where you are looking?

2. Maks need an hour or two to settle down. You can see heat distortion on planets and stars in focused and defocused images - it all goes in one direction.

3. After two hours have elapsed, and you are sure the previously mentioned aren't affecting anything. Check a brightish star at high power, and see whether the diffraction rings around it are perfectly round. Or throw the image out of focus - one direction shows a better bulls-eye pattern than the other (at least that's the case with my two Maks) - and see how concentric the rings of the Bulls-eye pattern are. If the pattern is just slightly off being concentric, the images will suffer. You'd need to collimate the telescope, if that is the case.

Cheers,
Renato

Camelopardalis
14-04-2014, 08:31 AM
Stefan,

1. use sidereal tracking. These mounts are susceptible to significant backlash, so set Goto approach azimuth to negative as we are in the southern hemisphere, and for the altitude you may need to try both approach settings to see which is better. The trick is to approach the object in the same direction as the motors would drive while tracking so as to minimise the backlash.
2. try running the focuser through its travel during daylight and you should be able to see the mirror moving - this works for SCTs but not sure if you'll be able to see it clearly with a Mak
3. under decent viewing conditions you should see detail such as the bands and spot. Jupiter is low now, and if the seeing wasn't good that would contribute. But also, what focal length eyepiece were you using?

04Stefan07
14-04-2014, 08:42 AM
I was using a zoom eyepiece so was switching between 24 mm and 8 mm.

Thinking back on the focusing I think there was cloud cover which may explain the in and out of focus problem.

Camelopardalis
14-04-2014, 08:47 AM
Yes, cloud or dew would do it :sadeyes: are you using a dew shield? I find that when my scope dews up I can tell from the eyepiece as it's fuzzy on bright objects.

04Stefan07
14-04-2014, 09:02 AM
Nah not yet, I need to get one for this OTA.

That is something I will get later though.

I remember I had tracking problems with the 130 SLT at the start but I somehow fixed it. Tracking I will need to get working then stability second.

Camelopardalis
14-04-2014, 01:51 PM
It's usually the backlash/gears that are the "problem" ... I find if an object starts to drift, then just hit the direction button in the direction of the tracking and see if it stops. It should, as the play has been taken out of the mechanism.

julianh72
14-04-2014, 02:23 PM
Yes, on my father's LX90, whenever you manually drive to a target, it always helps to "approach" the target in the same direction as the telescope will track, to get rid of the backlash in the gears.

If you approach from the other direction, the scope will seem to sit still for a couple of seconds while the gears "absorb" the backlash before it starts tracking properly, and in that time, your target can drift out of view when using a medium to high power eyepiece. If you have to approach from the "wrong" direction, it helps to "overshoot" a little bit, then nudge back to the target in the correct direction of tracking.

Amaranthus
14-04-2014, 03:44 PM
Once you hit 'align' for the final time, if you see the star drifting, then tap on the slew button for the opposite direction. It will then stop drifting and start tracking. This should not be an issue when you GOTO a new object.

This happens on my C8 sometimes. My backlash settings are at about 10-15 in both az and alt, which seems to strike a reasonable compromise.

04Stefan07
20-04-2014, 06:50 PM
Ha.

Funny thing is I ended up buying an HEQ5 mount which is solid as a rock, no more issues! :).

Just need to learn Polar Alignments.

Camelopardalis
20-04-2014, 07:54 PM
Nice one :)

04Stefan07
20-04-2014, 09:17 PM
I took it out today just to try out how stable it is.

I aimed the telescope at the tree not far from where I was. Aimed and when I started focusing there was hardly any movement at all. There is literally 0 wobble. :D

Camelopardalis
21-04-2014, 01:01 AM
And almost grab and go to boot :D

raymo
21-04-2014, 01:09 AM
Assuming that it is an HEQ5 Pro Go To, update the hand controller to
version 3.35, if it isn't already, and use the inbuilt polar alignment
feature. It's much quicker than drift aligning. One thing that from memory is not mentioned in the manual, is when it shows you the
remaining error after doing an alignment, it is not showing you the error,
it is showing you the corrections you have to make to the mount to remove the error. For example, if it says Alt -3 Degrees 32mins 10 secs,
that means you have to reduce your Alt by that amount. Just in case
you weren't aware of it, the further the mount is from level, the more
adjusting one axis will affect the other one.
raymo

04Stefan07
21-04-2014, 01:48 PM
Yep it's on 3.35 I'll need to try out the alignment.

Camelopardalis
21-04-2014, 03:51 PM
As a "northerner", previously reliant on Polaris, I find the polar alignment in the later releases invaluable...I use a C11 on an EQ6 and after running through a 2-star align and then the polar align, powering off and doing a 2-star align again it usually plonks objects in the FOV...and the scope has a FOV of a little less than yours :)