ckp82

28 minutes ago, TiffsAndAstro said:

 

this image below is my bestest attempt (with only free software) and a total of 13320 seconds.  i can see at least two other tiny galaxies, there's probably more. there's a lot of tiny galaxies about, it seems

 

How did you process this image? Maybe with all these clouds I might have to start playing with the images I'm taking, here comes the slippery slope everyone talks about 😆 

25 minutes ago, TiffsAndAstro said:

yes but there's not much detail in them  im extremely lazy and i wouldn't do calibration frames unless i thought it was well worth the effort. i think you'd have gotten them too if your fov was just a little wider.

 

 

What set up did you use? 

@TiffsAndAstro

Wow the difference is amazing. Have you captured 2 extra galaxies in your photo?

@PeterC65 thanks for the recommendation.

I used a lens cleaning kit which included an air blower, lens spray, lint free cloth ands a fine brush. I cleaned nearly all parts except behind the camera glass. I even took out the telescope glass to get behind them. I will definitely takes flats next time.

I think the light is coming from a streetlight outside the front of my house.

M82 stood out to me, even though I put m81 as the central focal point. I'd like to try easing out even more details once I get the basics down first.

Following on from my previous post m51 & pacman nebula I decided to have a go at m81 and m82.

I cleaned all the glass parts along the optical train. Unfortunately, there is a few dark spots remaining. In my next session I will have to try adding flats.

I also added the filter adaptor that was reccomended in my previous post.  I think it works better, your thoughts are welcome.

Anyway the following image is 50 x 30 secs. Any feedback would be much appreciated.

2 hours ago, daz said:

Darks:
Same duration as the light frames, and if possible, same temperature. Aim for more frames - 40 to 50, but again might need experimentation with your camera.
You will need TWO sets of darks - one for the light frames and one for the flat frames (these are sometimes called flat darks or dark flats, but are just darks!) The ones for the flat frames will be at the same duration as the flat frames.

 

Thanks for the explanation.

As I'm using asiair software it gives me options for lights, flats, dark and bias if I remember right. Would I just make another set of darks in the bias folder?

2 hours ago, TiffsAndAstro said:

Nina should work with your Nikon.

I'm using an Asi585mc and the asiair plus.

Thanks for your reply though.

30 minutes ago, bosun21 said:

I have found these to be too thick as they take up most of the M42 thread leaving the camera barely hanging on by a single turn.

I did see the reviews were varied but I thought I'd try it

34 minutes ago, PeterC65 said:

The camera tilt is probably fixable without a tilt unit. You could screw together the optical train and if you do this there are adapters (like this one) that allow a 1.25" filter to be fitted to the camera while still using the M42 screw connection. Screw connections are the most accurate, but you should be able to fit the optical train together with nosepiece / clamp connections and have no tilt (this is what I do). Make sure the clamps all have compression rings with two thumb screws as these are less prone to tilt. I would also check the focuser on your ST80 (this will also need a compression ring fitting). When you fit each nosepiece / clamp, make sure you turn it an check that it is home properly square as you tighten the thumb screws.

Yes, flats are taken with a white T-shirt or light panel over the scope objective lens. I sometimes use them but mostly I don't. Flats are quick to take but quite fiddly to get right and they need to be taken with the optical train you are using on the night (and re-taken if you change anything). As I understand it, flats also need to be used with darks (taken with an opaque cover over the scope objective lens). Darks are not so fiddly and you can take a set at different camera temperatures and use them across sessions, but they take longer to take.

I use SharpCap for EAA which has a hot pixel removal and a background removal feature, and used together these do almost as good a job as dark frames but with much less fuss. Then if I'm not using darks I don't use flats. In my (relatively limited and EAA only) experience, darks and flats only make a worthwhile difference if you are pushing your optics, so using high magnification or observing difficult objects. For example, I only take darks and flats when I'm using the Explorer 200 with a Barlow and am trying to observe faint galaxies or nebulae.

I'm sure its a different story for AP.

I never knew these adaptors existed. I've ordered one as I like the extender tube screwed into the focuser tube rather than the grub screw holding it.

I'll have to have a play about with the different type of frames.

1 hour ago, TiffsAndAstro said:

You will be shocked by what calibration frames will do for your results.

I've just watched a video on what calibration frames are and see that bias frames are taken with the quickest exposure possible and darks are the same as lights but nothing about the exposure time of flats. What should these be?

1 hour ago, PeterC65 said:

I don't think you're out of focus. The star shapes look like you have a problem with field flatness. I get this around the edges of my refractor images but with the widening smudges pointing outwards towards the edges of the image, so with stars on the left the smudge is to their left and with stars on the right the smudge is to their right. You have these smudges right across your image and all pointing to the right, so I'd say you have an issue with camera tilt.

The dark circles on your M51 image are caused by dust. You can get rid of this sort of thing by taking flat frames but taking flats is quite a bit of effort. I would check your optical train for any obvious signs of dust and try to remove it. It could be anywhere in the optical chain, from the camera window to the scope objective lens.

The M51 image has quite a bright background, particularly in the lower left quadrant. This might be caused by dew on the telescope objective lens. The dew scatters light from other sources, such as nearby terrestrial lights or the Moon, which brightens the background. In this case the brighter background is also making the dust spots more obvious.

When you get your narrowband filter it will make the background darker so that you will see the Pacman Nebula more clearly but even without the filter you can make out the shape.

 

Thanks @PeterC65

How would I go about fixing the camera tilt? Is the only way buying a camera tilt unit? I can screw the camera and extender tube onto the end of the scope but if I add a filter I have to use a nose piece for the filter to screw into. This is then held in place place with the grub screws. Could this be the problem?

I haven't a clue about flats, darks and bias yet. Is the flats where you put a white t shirt or light panel over the lens and then shoot so many shots at the same exposure? I'll give the optical train a good look over for any dust or marks.

Thanks again.

I finally managed to get out last night to get reacquainted with my setup and see what I could see. I'm still new to eaa so my images aren't as good as some on here, but I'm happy with what I can see and hopefully with more experience I'll be able to tweak and ease out some more detail.

I used a bahtinov mask to focus. In hindsight I think Vega was too bright to do this on as in preview mode it looked spot on but I've got some strange looking stars, maybe it's the tracking? Any advice would be greatly appreciated on how to make a better image. I think I may also have some dust or dew marks on one of the lenses which can be seen in the images?

I'm waiting for my dual narrowband filter to arrive but had a go at the pacman filter anyway. I took 55 x 30 seconds images and can start to see the colour and shape come through, I'm guessing with the filter I'll see more in the same time frame?

M51 was 15 x 30 seconds

Equipment used were as follows:

Skywatcher st80

Skywatcher azgti and wedge

Asiair plus

Asi585mc 

Svbony ir/cut filter (I heard this filter stops star bloat?)

Thanks.

Thanks for the link @StevieDvd and the explanation @saac

This seems too easy. Last time I tried I couldn't get it to work. I must have been using the synscan app before, it was a while ago. I'll follow your advice next time I try.

Thanks.

How do I go about finding the moon using the asi air plus? It isn't as easy as typing in the moon and watching the telescope slew to it.

I know the easiest way would be to do it manually. However, I don't have a star diagonal or rdf as I bought this telescope purely for eea. It is a lot harder than you would think trying to do it without these.

Thanks.

I caught one not so long ago 

3 hours ago, AstroMuni said:

Take a look at the Antlia triband RGB filter. Many of my friends use it for EEVA and get good results.

See this review...https://www.skyatnightmagazine.com/advice/multi-band-filters-astrophotography

Thanks for replying Astromuni, but I have already ordered the optolong.

Thanks for the welcome Coco

Thanks @PeterC65

I'll go with optolong then if they specialise in filters.

Thanks for your suggestion.

I've had a look at the options and at the moment I'd like to keep the costs low so I've decided on either the optilong l-eNhance or the ZWO dual narrowband filter. Other than the price point (£30 cheaper), ZWO has become a brand I like and trust, having the asiair plus and Asi585mc camera.

Technical charts and jargon goes over my head, so out of these 2 filters is one better than the other or are they the same quality and do they do the same job equally?

Thanks again.

Thanks again @Steve in Boulder

So for galaxies and reflective nebulas leave the filter off and put it on for the other nebulas if they contain H-alpha and/or 0lll signals.

I don't know if I could progress to astrophotography, it's enough learning the basics of e.a.a!

My camera is an osc camera.

1 hour ago, Elp said:

If you're very patient they do come up used cheaper. I had the black ioptron one which I'd class as second best out of the four I used, I believe they do a newer one which looks a lot like the WO one, but I haven't used the newer version.

Patience isn't my strongest point. It's something I'll have to work on I think!

Thanks for replying @Steve in Boulder

So for reflective nebulas I wouldn't need a filter and for emmision nebulas I would need a dual narrowband filter. 

For planetary nebulas and super novas like the crab nebula for example, would I need a different type of filter all together? There seems to be a few types of nebula and alot of different filters.

Thanks.

I've only ever imaged galaxies when doing e.a.a. What kind of filter would I need to pick out nebulas? The only filter I own is a svbony ir/uv cut filter.

Thanks.

I've done some reading online and it seems the skywatcher mount has to much slop in it, I thought it was just me! As this is the weakest link, I think I'll look into getting the William optics wedge as my first upgrade. It's expensive but it's half the cost of the s50 and will still be a better set up overall.

2 hours ago, Elp said:

I suspect your SW wedge is part of the problem. Some people use it okay and I guess it depends on payload and FL being used, I've used various types of setups on it, and four different types of wedges and the SW one ranked near bottom. If you're going to use the azgti long term, just get the William Optics wedge, trust me.

I've read a few posts about using the asiair in alt az, most people eventually admitted they used Synscan to align (so not using the air). One or two people have said they use it fine in alt az but I don't know how plate solving and goto will work with one in alt az.

I was thinking the same to be honest. I can do a small adjustment but the numbers say I've gone alot further than it should have if that makes sense?