Nicola Hannah Butterfield

@ONIKKINENI know about the mirror clips issue. I have to take the mirror out for a clean, so might do something at the same time. Thanks for the input.

On 08/11/2022 at 09:55, Elp said:

They're nice images. Are you sure you have your backspacing as best as you can get it, it looks more like the sensor is a bit too close more than coma. Coma patterns from my experience flare out more making the stars triangular or seagull shaped.

If you look at this, which is a single 120s exposure 400ISO on a Canon 40D of M44, especially the edges you will see the coma, the previous 2 images I shot on the 6D, the centre stars whilst not perfect are not bad, to say I am only a week back into this after nearly 6 or 7 months out.  The stars start to stretch and the further you go, the worse they get. This is simply a jpg conversion of the raw, nothing done.

@mrossI have a 200P and I can focus both DSLR and my ASI 120 MC, the DSLR is very close at only about 1CM the ASI is much further back requiring extension tubes, I would image it is very similar with the 130P. What I have done is to focus each on a distant object during the day, (for me a wind turbine some 2-3 miles away) once I have focus I marked the focus tube at each point, you then have a starting point for the fainter night objects.

This was focusing the guide scope with the ASI 120MC guide scope is 40mm 127mm fl

The front vegetation has gone, just some sunflowers, and you really don't want to see the LP from those warehouses, they are what stops this area being a bortle 5-6 instead of over 6.

@SoftwareDeveloperThanks for your input, however I know what is causing the light bleed at the NE position, it is the focus tube into the main tube.

I am not worried about the diffraction spikes bar the image was soft, it was merely meant to point out the problem, I have much sharper images, it was just the first that came to hand, I don't tend to keep test shots on stars.

@malc-c I am still on the stock focuser, the link was to ask if it would improve things without modding the tube by an inch or so.

It isn't so much the secondary spike, but merely what do I fix first comma or a shorter low profile focuser, to fix the light bleed caused by refraction around the focuser tube.

This is from the central stars in M44  yes I know should have shot it 90 degrees.

Just a single 2 min exposure from the raw file, it is shot on a Canon 40D and a SW 200P. I think I have answered my own question here. Given this single image coma, I think first.

Coma or draw tube incursion.

We all know coma, this should be uniform across the image, tube incursion more subtle as it only affects one side of the star like this, yes I know a little soft, but you will notice the light bleed to the 2 o'clock position,

Is it better to fix this first or coma, I use a SW 200P with currently a Canon 40D I know any fix will involve the complete optical train. Will the https://www.rothervalleyoptics.co.uk/ovl-dual-speed-2-low-profile-crayford-focuser-for-newtonian-reflectors.html give an image without intrusion and also be closer to the tube for say a coma reducer or a camera rotator without cutting an inch off the bottom of the tube.

@ElpThanks for the input.

If you look at the diffraction spikes I think that is showing some of the coma effect as those on the right left to the left and those on the left tend to the right, the actual coma on the stars isn't so bad, but then it is an crop sensor, that of my 6d is full frame and is much more noticeable, and this image is cropped a little.

I believe the Baarder MPCC3 also a doesn't change the focal distance and would I believe just replace the 2" nose piece which has an M48 EOS. I say this as on occasions I do shoot larger objects like M43 and M31 I can't quite get them especally M31 in the full frame, but you have to work with what you have.

Again, you can see the coma effect of the diffraction spikes. That was shat on the 6D with the 200P as was this

You can see the coma on that one.

One day I might get this close, thanks for sharing an amazing image.

@BabyJo84 hopefully many better answer will follow, it seems the scope is more geared toward astro photgraphy, ’tis why the planets are small, deep sky will appear dim visually because of its limiting light gathering. The rest I know little on.

52 minutes ago, Elp said:

I think it's a nice effort. Have you considered using an Optolong L-extreme, works very well on emission targets. Not sure how much effect your internal IR filter will have though, works well with my modified Canon.

Thanks. I need to invest in a coma corrector first and possibly a manual rotator and possibly a better/low profile focuser, a lot of the standard SW one pokes into the tube, though the stars I seem to be getting of late don't seem to have been affected too much.

One thing I have noticed, is there is a lot more gas a dust, I have been until I got the new light panel, been thinking it as imaging flaws, and whilst there may be an element of that still. I also need to work on image processing a little more and even though my stars are better you can still see the coma in the diffraction spikes. I also need to analyse my subs a little better, for example in this case I have 110 subs, would it be better to choose the 55 top SNR ones, is there an SNR number above which you don't use for certain images for certain objects.  I do live in a bortle 6 thanks Wakefield council, for bringing it down 1 notch, so LP is always going to be difficult.

I would love to get filters etc but being on ESA this hobby was never going to be easy, so step at a time, it takes me time to save, but the core needs to be right first, no point spending on things if your basic image isn't right, I do think after the light panel investment I am moving in the right direction.

I also need to look more at images of objects I might image and look to see if there are clouds of dust ect, I might want to get rid of on the pp side.

I will never win any awards on this side of imaging things as a whole, but it is interesting sometimes to see I CAN match superior scopes in light gathering, 2nd image specifically, light diffraction on the first much superior to mine, my highlight detail is better.

All that said, it is all subjective as we all see things differently, even in what is deemed correct.

I spent a lot of time imagining this on a non modified Canon 40D to end up with just 3hrs 20min of data at 400 ISO, at first i was a little disappointed but knowing it is really suited to the 40D and the moon being present, I did a search on the net, and whilst yes it isn't great, it does I think compared with some images of similar quality from much better scopes and imaging techniques if I am reading the information correctly.

Hopefully this is aloud

https://www.utopia-photography.ch/universe/i/01/p23.html

https://www.flickr.com/photos/97939735@N04/37903269415

On 31/10/2022 at 20:11, Elp said:

And also after meteor shower peaks.

I was on Skye Nov 99, the flashes behind the clouds were amazing, following day clear as a bell.

@Ags thanks.

@Paul M I like seeing stars in images, it puts a context to the enormity of the cosmos. I like to see how far a photon of light has travelled as well, furthest so far about 3.2 billion LY. Though, I seem to have lost the website that had a database of all the distent ones.

I have read that the eqmod interface has a gamepad option for control. Well recently I have just set things back up after a computer repair, and the software seemed to be putting Jupiter out by about one hour, so I though get a game pad as it makes remote moving the scope easier  turns out my old wingman joystick works, pov working like a litter joystick on a gamelan.

Mind it wasn't entirely necessary as it turns out the software was on European time, it occurs to me Saturday with the clocks going back. All sorted now.

17 hours ago, mareman48 said:

WOW 🤗

Thats pretty sweet, far better than any of my attempts.

Thanks, I am using my Canon 40D instead if the 6D, whilst the 7 has a wider field of view, until I get a coma corrector it suffers terrible coma, the 40 does but much less so.

The rest is practise, I have struggled a little changing from BYE to APT, but in the long run it will be easier if I change to a dedicated astro camera.

Being able to take consistent flats with the LED light panel I think is paying dividends as well, shooting consistently at iso 400 enables me to reuse bias and darks, providing the same temp range, it is a thing you don't have a great deal of control on a dslr, things you can do to cool it, but it is likely to always fluctuate a little. So I can now spend more time on the lights, knowing bar a sudden down poor, I will always get flats to correspond to the lights. I can't off the top of my head remember the previous light's duration, but I know the flats would have been awkward.

I have also been working on processing, I am attempt to image as many Messier objects as I can, not spending too much time, but if I can get an hr subs on most, should be able to get some form of an image on most, planetary ones are going to be troublesome, with what kit I currently have M57 so far has been disappointing due to its size.

I did M33 back in Jan from the records, however since then as you may have seen, I have had a few problems, and having lost my BYE keys, I thought I would try APT, and with a bit of help from those on here, I seem to have things working.

30x2min subs, with 30, bias, darks and flat, dew become a problem to guiding and to the mine mirror a little, so a little work to do yet with settings, but it seems to guide pretty well to two mins, though the meridian flips either through the focus out, I need to get a new M48/EOS mount this one has a little movement in it, as stars in the couple of frames I did get had some distortion, not sure yet if it was focus or guiding.

Anyway, for what it's worth.

This was Jan's effort.

@bottletopburly

Hi, sorted, both issues, though still get the odd solve error, since I am shooting on DSLR my settings are slightly different for plate solving, GOTO attempts different as is pause after GOTO as well. I find I need about 8s at f5 and 3200iso, though this I think will vary depending on where in the sky, low SE to SW heavy LP, but as we have had new LED street lights fitted the overall bortle has drop from 7 to 6, it's the likes of the next warehouse with indiscriminate lightning that's causing it. I will attach a 📸 when I am on the 🖥 later.

This is virtual 360 degrees,

The search light is virtually due south as viewed. The bright lights centre are Next and the industrial park around it, SW Barnsley, SE Doncaster. I am also plagued with a security lighthouse centre right of the semi, shines in the house, fortunately the garden fence just screens the scope.

19 hours ago, Craig a said:

I think this is fascinating, it actually looks like it’s meant to be there 

It was a light artefact from the moon which was close that night, I have the month wrong it was Jan the 6th 2021.

On 24/10/2022 at 16:48, 900SL said:

It looks to me like a rip in the space - time continuum. Did you see any strange shimmering off worldly entities looking for a cheese sandwich after the event?

 

I thought the doctor fixed that rip.

@bottletopburlyIt might be the Auto Cancel Distance, I have everything on, as you have pointed out. I then just get a message saying dither cancelled or some such. I seem to have sorted the focuser connection out as well, well at least it didn't disconnect whilst it was connected to APT last night, and that was a change of cable from the supplied one.

There is also a slight issue when it plate solves sometimes, I think one or two of the database are corrupt, it says missing, and I have tried reinstalling. The thing is it gets close before it fails.

2 hours ago, Ouroboros said:

I think that’s a pretty good image given it’s only 17 x 1 minute exposure,  plus the other issues.  NGC 2175 is a pretty faint target too.  It shows you’ll get better results once you get your guiding sorted out.  I was intrigued by what you meant by a “light cover for the mirror end”. I understand the light shield for the front. That’s how I do it by placing a t-shirt over the front end.
 

Thanks, I used Starnet to extract the nebula and extract from the image in pixinsight, so I could work on both separately, so I was able to hence the color of the stars without going to OTT and reduce noise in Topaz Denoise, but there was too much.

Regarding the tracking, it seems to be tracking fine now, this is a single 2 min sub of M103

But it won't dither (not that there is much chance to do more than a few frames at a time, of late), I think it has to do with some settings in APT, like wait time or time out.

I ran guiding assistant in PHD2, not sure if it helped, as it was tracking fine before, but hadn't imaged anything, so I can't compare.

On a plus note though, I had it running smoothly on remote desktop, I had to really think which screen was the remote computer.

Tracking with PHD2 was good, but as soon as connect APT to the mount, mmm problems to resolve,

I think I imaged Pluto, maybe, just a spec,

1 minute ago, bottletopburly said:

Enable server in phd2 > think it’s in tools  for dithering to happen 

It is, it was auto enabled, but I will have another look, to be sure. There were some really weird things going on, the RA and dec lines just went right of the scale when trying to track, Tues/Wed having changed nothing PHD2 was tracking, albeit with a little wind turbulence. A few more clear ish nights should have it sorted.

I used to use BYE for camera control, but lost my log in details, I have tried getting in touch, well starting to get me head round APT now.

Thanks for the input.

Having finally got the computer in the shed working and all the software installed, still a few clichés to sort, i.e. APT and PHD2 don't want to seem to dither.

There haven't been too many clear nights and sort of torn between getting a few images, and sorting out various bits i.e. guiding plate solving, things you can't do in the daytime.

Equipment, Canon 40D SW 200P. APT

This is what I got frame stacking.

This is what I ended up with.

I know there is a lot wrong, but this was only from 17 60's subs, and no guiding, so stars are off a little, no coma corrector so a little stretched towards the edges, though the 40D has helped with the crop compared with the 6D

There is also a dark band showing down one edge, top in this image, and can be seen as excessive noise, but that was before I collimated and sorted the focus and USB hubs and cables needs, those two hubs need more than just sticky back velco.

However, to say it is nearly a year since I did anything bar a bit of planetary, the coma issue and not being able to get reasonable flats, I have also made a light cover for the mirror end and a light shield for the front, the flats being cured by a cheap LED A3 light panel, just point the scope to the zenith, which is a saved park position in eqmod, place the panel on the top and shoot, cost £20.

I guess better processing might improve it somewhat, but everything considered, I think it isn't a bad attempt at getting back into things.

This is just from 6x20's ISO1600 images, I have made a cardboard rear cover for the scope, covered in black gaffer tape, like wise a light shield that is about 12" long, this has cut-outs for the spider nuts and focuser, only thing I for got to do was cover the camera, I did the lights with the new £20 LED light panel, which seems to have worked a treat, this is a crop as I still have a coma corrector to get.

This is the full frame shot on a Canon 6D SW 200P with just a ABE extraction

which was this

This was shot overlooking Barnsley to my S.W. at about 9.30 24/10/22

So I am not sure if that excessive light is the camera being uncovered, I do have a lot of local household LP at this time of night, or from Barnsley.

But apart from that the light panel seems to be working, and for £20 I think it's a bargain.

Just need to sort out a few other niggles, like plate solving.

Not sure, but this was a light artefact when I imaged Uranus last Oct

So maybe something like that.