Sabalias

Just now, CraigT82 said:

Sorry I meant the AP images you captured with the scope, what what it in those that suggested collimation was out? That might guide you in what to look for

Ah, I follow. It was suggested here that I might want to check the collimation as the stars are a little egg-shaped.

Stu

2 hours ago, Spile said:

Here is my interpretation. If the axis runs as indicated (10 o'clock - 4 o'clock) then it would be good for me. However the other photos show 9 o'clock - 3 o'clock which means there would be an offset error.

How do you mean? This is something I haven't come across before.

Thanks,

Stu

8 minutes ago, CraigT82 said:

What was it in the images that suggested a collimation issue? 

Just the fact that the secondary alignment has moved after bring the primary into view. I don't really have a frame of refererence so I don't know what I don't know (trite answer perhaps).

Stu

43 minutes ago, Astro Noodles said:

Although many people have pass-times, I imagine far fewer have a hobby. I, (like many on here I suspect), have multiple hobbies, and I live for them. If I suddenly didn't have to work any more, I would never become bored. If my current hobbies couldn't expand to fill my time, I would just get more hobbies.

Astronomy is my latest hobby and as far as I can tell, it is more popular than it has ever been. Far more accessible in terms of equipment, price, information than it could ever have been even 10 years ago. 

Rather than fragmenting, I just think there is more to explore within astronomy as a hobby, which means it can be more appealing to a wider base.

Ditto!!! I have a number of friends who constantly say they would be bored when they retire (so they aren't planning on retiring until they have to). I, on the other hand, am looking forward to my retirement and the joy of being able to carry on with my hobbies with more passion than I can today.

Stu

3 minutes ago, CraigT82 said:

Looks pretty good to me, but I cant really see the 'dot-in-the-donut' cheshire view in the last image though as it is out of focus - that is the primary collimation and is the most critical one to get right.

It's worth doing a few iterations from start to finish.... so when you get to your last photo (primary collimation), start again with the concenter and go right through up to primary collimation again, the errors at each stage will tend to get smaller with each iteration I find.

Thanks Craig,

Yes, the joys of taking a photo with your phone - just couldn't get it to focus on the mirror under the crosshair.

Stu

Hi All,

I was wondering if anyone could asvise me on whether this is good collimation or not - generally, when you look online everything seems to be absolutely perfect so it's difficult to compare. Also, I have had problems in the past with the focus tube being off-centre (now adjusted) but I can't seem to get the secondary/primary alignment exactly right while maintaining a spot-on secondary adjustment.

First I used a concenter to make sure the secondary was in a good position and orientated properly:

Then I checked with my cheshire:

Then I had to adjust the secondary to see all of the clips on the primary (it's slightly off but the picture is slightly off to so it seems to be a bit exaggerated:

Then I checked the secondary again with the concenter. It isn't as good as the first image but not quite as bad as the third:

Finally I lined up the primary:

Does this seem to be ok for a collimation? In other words - am I expecting the almost impossible?

Many thanks,

Stu

Update:

I recently tried out some AP with my kit and the result seemed to show that the scope might be slightly out of collimation so went through the whole process again. I found that the secondary was very slightly off so I centred that using my concenter and checked with the cheshire:

Then I found that the secondary wasn’t lined up with the primary - I dealt with that:

then I went back to check the secondary and found that it was, again, very slightly off according to the concenter but I chose not to make any further adjustments:

Finally I adjusted the primary:

looking at the photos, can anyone tell me if there are any glaring errors please?

Many thanks,

Stu

3 minutes ago, Located said:

Appreciate these fast response guys, yeah I read somethings about the 130/150 heritage and does look good but was looking to have one on a mount. Would it still be recommended to maybe consider this and a mount or switch to something completely different? 

I may have missed something in the previous comments but, ultimately, your decision needs to be influenced by what you want to do. Will you want to take photo's of deep sky objects or just carry out visual observing? For the former you can very easily spend a fortune but for the latter you can get away with spending much less. So if you are only planning on visual observations a good dobsonian setup with some nice eyepieces can be more user-friendly and easier on the wallet. Very generally, I think the following points are truisms:

• Wide aperture = lots of light-gathering
• Long focal length = greater magnification
• Better quality eyepice = clearer image (and probably wider field of view)
• Mount capable of taking greater weight = more stable platform; but........
• An Alt/AZ mount is far easier to manoeuvre manually than an EQ mount

Stu

I have the Explorer 150 PDS and I've not been disappointed with the scope at all; however, I did decide to sell my EQ5 Pro and upgrade to an HEQ5 because I was right on the limit of what the mount could handle for photography (which is something I wasn't expecting to get involved in when I started out).

Stu

Hi there,

It's also worth mentioning that you may need to collimate the focus tube. Mine was off and, as a result, I couldn't get the whole of the primary in view when the secondary was true (the problem was diagnosed by others on this forum). Useful video (doesn't show a 200PDS but it is still relevant) -

Stu

14 hours ago, michael8554 said:

To verify that the GoTo after PAE has put the target in FOV, take a 30 second exposure at maximum ISO.

Hi Michael,

Sadly, I couldn't get anything other than a washed out image at max ISO 😄 - the skies were still too bright. As the year progresses I hope to be able to follow this process though.

Cheers,

Stu

18 hours ago, malc-c said:

Just my 2p worth

If you have good alignment and can slew to a bright star near the target, then chances are the mount won't be off in the goto.  For example if you centre Vega and then slew to the ring nebula it should still be within the FOV as any goto error won't be large enough to make it well outside the FOV.  I would put my money on one of two things.  Either you've forgotten to refocus through the camera, or you're on target, but you are expecting to see something in live view and the target is just not bright enough to register.

Having done your alignment routine, remove the eyepiece and insert / attach the 600D.  Place a Bahtinov mask for the scopes focal length on the scope and take a 20s exposure.  Adjust focus until the middle line is central and equidistant between the other intersecting lines to get focus.  Remove the mask and now select the target.  Depending on the target, a 30s exposure might confirm position (such as the bright core of a galaxy), or better still, do a two or three minute exposure which will confirm the target is in the FOV.  Once you have the target confirmed proceed with guiding and then run whatever plan you have set in APT / Backyard EOS / NINA or whatever app you use.

Good luck

Thanks Malcolm,

I managed to get the dumbbell nebula in the FOV of the camera but my concern was that it wasn't close to central - I completely lost he veil but that might be because it's a fainter object. I've ordered a Bahtinov mask now though as focusing seems to be a challenge through a camera.

Stu

13 minutes ago, PeterCPC said:

Try them both during daylight and you will be able to see how they compare.

I'll do that Peter 👍.

Thanks,

Stu

1 hour ago, michael8554 said:

That should allow an accurate GoTo a nearby Target.

From what I've just read, getting a PAE is not straightforward:

Hi Michael,

I can attest to the relative complexity of the process 😂 but I believe those are the steps that I followed. I'll have to give it another go and make absolutely sure next time.

Stu

15 minutes ago, M40 said:

Have you tried slewing to a known object eg vega with the camera installed then looking at vega using live view of the camera? Is vega centered on the camera display?

Good idea. I'll give that a try next time I'm out

Stu

52 minutes ago, carastro said:

It sounds like you are doing everything correctly, especially since Vega is ending up in the eye piece. 

A few comments.

The point of focus will be very different to the eyepiece with a camera, can you see stars with the camera but just the wrong ones?  I would suggest you find your target with the eyepiece first, then change to the camera and then re-focus.

Also depending on what camera you are using, if it is a colour camera again depending on the model, they are generally not good for seeing what you are looking at in live view, you may need to do an exposure of several seconds to see what you are looking at with a camera. 

However this may not be the problem.   It might just be a case of your mount not going to the target as you say.  Fiddling around with changing eyepiece to camera can knock the alignment off a bit.  

I have been imaging for around 11 years and even now I sometimes have the occasion when the mount doesn't GOTO where I want it to despite alignment.  These days I tend to only do a 1 star alignment on a star close to my target and find that works much better than 2 and 3 star alignments.

Hope some of this might give you some food for thought.

Carole 

Thanks Carole,

I'm referring in particular to a session where I was trying to image the veil nebula but it didn't appear to be in the camera field of view at all (taking a 10 and 20 second, high ISO exposure to see). I switched to the dumbbell nebula and found that the object was way off to the side of the camera FOV; at that point I stopped the tracking, centred on the nebula and then started tracking again before initiating guiding. It's reassuring to hear that this sort of thing just happens and that it's likely to be my ham-fisted efforts at switching eyepiece for camera.

Stu

57 minutes ago, PeterCPC said:

What is the field of view of the EP compared to the camera? Weight could also be an issue.

Thanks for responding Peter. The eyepiece is 68 degrees but I'm not sure about the camera - it's an EOS 600D

Regards,

Stu

Hi everyone,

I'm a bit confused about the tracking on my HEQ5 Pro. This is the process I follow after setting up (including balancing and starting in home position)

• I try to accurately polar align the mount
• Carry out an 2 or 3 star alignment
• Do a test slew to a known, visible object (last time it was Vega) and the object is nice and central in the eyepiece
• I even carry out a PAE with a star close to where I am imaging

Now I'm ready to look for a DSO that I can image but the object winds up far from centre (and in some cases not in the field of view at all). The only thing that has changed is the very careful replacement of the eyepiece with a camera (weight is different but not significantly so); is that likely to knock the alignment off?

Many thanks,

Stu

On 19/07/2021 at 20:55, malc-c said:

Stu,

With the USB cable connected the handset has to be in PC-DIRECT mode in order for the PC software (EQMOD / GSS / INDI drivers) to communicate with the mount.  The V5 handset has a built in USB to Serial chip (based on a CH340 chipset so you will need the driver from Skywatchers website).  Once the diver has been installed and the handset connected to the PC via the USB cable, and the handset connected to the mount you need to place the handset in to PC-Direct mode.  If everything is OK the application on whatever platform should see the handset as a new com port (I've only used a windows platform so can't give you any help with Astroberry)

Thanks Malcolm. I'll look into that.

Stu

Not sure about ZWO ASI but I run my Astroberry off a 26800 mAh power pack which has up to 3A output per USB port. There’s enough power going into the Astroberry for it to drive the power requirement of my ZWO120MM guide camera. 

regards,

Stu

On 08/08/2020 at 05:10, AstroScout said:

It provides USB connectivity without needing to use an RS-232 to USB adapter. 

I use this port on my hand contoller to connect to a Raspberry Pi as a WiFi hub and then control the scope over WiFi from an iPad running Sky Safari. The advantage of this over using a Skywatcher WiFi adapter is that the hand controller still works. It is a lot easier using the physical arrow buttons for fine slewing control while looking through the eyepiece than it is to use the virtual buttons on the Sky Safai screen.

Hi AstroScout. Sorry to resurrect this old thread but I am trying to do exactly this but kstars is saying that the controller is not connected. Did you have to jump through any particular hoops to get your handset and Astroberry talking to each other?

Many thanks,

Stu

16 minutes ago, vlaiv said:

This is very good for first DSO image.

I'd say that first thing to do is to check collimation of the scope.

Stars are not round and they change shape across the image and my first guess would be that scope is not quite collimated properly.

Second thing of course is to plan for flats in the future

Thanks Vlaiv. I did have some serious issues with collimation last week when I started using a concenter, it turned out to be focus tube alignment. I thought I had sorted it all out but maybe I missed something or the primary moved out of alignment a bit between my tinkering and imaging. For the flats I suspect I'll have to wait a little while for some longer nights and use the white t-shirt technique 😆 - here's hoping for clear skies in August and September!

Thanks all. The focuser was a bit off so now adjusted and everything seems nice a true.

Stu

Thank you both. I didn't realise the focuser itself could be out of alignment but of course it makes absolute sense. Live and learn.

Stu