Communal Night-Sky Photography Thread

[birdboy]

Originally Posted by Phill D

Yes nice to see it whatever you took it with. Just out of interest could you have done that with your Oly kit?

Just like to add to what Dave has already said. Yes such an image is possible with Oly equipment and a Star Adventurer with many riders. It would need an 300mm F4 lens + the MC1.4. You would need very very precise polar alignment and you would need to guide with a guidecamera. You will need to find the galaxy using I would suggest plate solving software. Last but very important you need the best dark sky you can get to. I have previously posted an image of my setup, Oly equipment with Star Adventurer. It includes 2 guide cameras 1 mounted inline with the polar axis and 1 aligned to the imaging camera and lens. My guide cameras were about £135 each from Altair Astro cameras and £50 and £130 for the guide scopes. Alatir Astro now do a guide camera bundle. I would recommend these mainly because you get a free 1 year licence for SharpCap Pro. I cannot praise SharpCap enough it allows many things but in particular I use it for polar alignments and keep it running when I am trying to find my targets. For finding my targets I use SharpCaps plate solve with the guide camera aligned to my imaging camera. Having set it up once with All star plate solver (freeware) Sharpcap takes an image and solves the centre point in RA and DEC coordinates. You then need to adjust you RA and DEC amount to get to your target.

I have modified my Star Adventurer mount to make it more rigid and to help with finding my targets DEC.

Something like the Needle Galaxy is very very challenging for this type of mount equipment. I would also strongly recommend getting to Know Stellarium very well in particular the tools section top right hand corner (trhc). Set up your sensor (Oly camera) and telecscopes (Oly lenses). If you then do a search on say the Needle Galaxy and click the rectangular box in trhc it will draw a red frame around the image representing what you should see on the back of your camera without having taken a single picture. Its by far the best way to see what your particular setup is capable of imaging with the right tracking, best polar alignment, PHD2 guiding and dark skies.

[birdboy]

Here's M101 the Pinwheel Galaxy using the above setup. Oly OMD EM1 MKII 300mm F4 MC 14. 192 x 60 sec ISO1600 stacked in DSS processed in Startools.

M101 is about twice the size of the Needle Galaxy's longest bit and is a lot brighter.

[wornish]

Lovely image John.

You certainly get the best possible results from your Oly and the Star Adventurer mount.
For me, it seems that it ends up being about your local night sky seeing, then your light pollution, then your patience and finally your gear.

Truly clear skies are rare in this country, that's why many observatories are on top of mountains in far off places. We locals can however still try and make do with what we have.

[Phill D]

I agree that's a great image John. Good to see what the Oly kit can do on a tracking mount. Shame it took a 300m to get it though as I don't have one of them either so maybe it's not worth me getting a mount just yet.

[birdboy]

Originally Posted by Phill D

I agree that's a great image John. Good to see what the Oly kit can do on a tracking mount. Shame it took a 300m to get it though as I don't have one of them either so maybe it's not worth me getting a mount just yet.

Phil You can get great images of galaxies and nebula with shorter slower lenses. What have you got? But I would suggest that you put what Oly lenses you have in Stellarium and have a look around the sky at what will reasonably fill you field of view. M42, M31, although not at this time of year. The Heart and Soul Nebula, Rosette Nebula, Pleiades are examples that will look ok in a 150mm lens.

Even with my combination the choice is limited and I am hoping one day I will up my lens to something like an Edge HD 800 with an 200mm aperture and focal length of 2032mm. The problem is I will lose the ability to remotely focus using Olympus Capture as I can with my Oly equipment.

The Star Adventurer is a great cheap mount to start with but there are increasingly other better mounts for double the price. The SA is not a goto and finding these galaxies is not easy at first. If you have not got long focal length lenses and you really want to give this a try there are some good mounts and telescopes that you could use with your Oly camera but they start at about £2100. This will give you plenty of objects to image and a goto and reasonably portable. Be wary of buying cheap doublet telescopes for imaging. e.g This has some good reviews.
https://www.365astronomy.com/Celestr...Telescope.html

The other thing to consider is the time of year and whats is around in the skies from your location. There is less astro darkness for the next month and then there is none until about August. The really interesting time I think is from September to March. The really good news for you living in Derbyshire is that you must surely be only a short drive away from some really good dark skies.

[wornish]

What a difference a night makes. This image is a combination of 4 x 300 sec for each R, G, and B channels. Images were taken 26/4/19 with no Moon and clear skies.

[MJ224]

Superb Dave...…………...

[OM USer]

Yes, superb.

[Phill D]

Thats a cracker Dave well done.

And thanks John for your comments definitely food for thought.

[birdboy]

Whirlpool Galaxy (M51) with NGC 5195 on its arm. 31 million light years away One nights worth of imaging.

Olympus Em5 MKII 300mm f4 + MC14 1600; 143 x 60sec about the size limit this equipment can image, heavy crop. Stacked DSS and processed in StarTools Colour has not been adjusted in ST any bias was taken off.

[wornish]

Superb capture. Very little noise as well.
Did you also take flats, darks, and bias frames to use in DSS?

[birdboy]

Thanks Dave

For this image I only used 15 dark frames in DSS. I also processed it without dark frames and to be honest I can only see a slight improvement over the dark frame subtraction. I think my time would have been better placed taking more light frames than the dark's. I am so confused about if the calibration files are needed.

[wornish]

I tend to agree about darks. Your image if pretty much noise free as far as I can tell from what you have posted.

Flats, however, do make a big difference if you have any dust bunnies on your lens or filters if you use them, or to remove any vignetting that you can get on large targets. If this is a large crop I guess that solves that potential problem as well.

[birdboy]

Originally Posted by wornish

I tend to agree about darks. Your image if pretty much noise free as far as I can tell from what you have posted.

Flats, however, do make a big difference if you have any dust bunnies on your lens or filters if you use them, or to remove any vignetting that you can get on large targets. If this is a large crop I guess that solves that potential problem as well.

Chers Dave. I tried the flats calibration files and found them limiting. First I found dust bunnies can move when I change the battery and you need flats exactly as your camera and lens are orientated. I clean the lens and exercise the sensor cleaning before starting and keep lens separation from the body to a min. I can remove vignetting easily in Startools. This is a crop and representative of the full image. I think that the calibration files are best for CCD astro sensors and there they work. For DSLR CMOS sensors there is less benefit. Darks can help CMOS when the exposure is long. By keeping the exposure short I get more frames and therefore less noise when stacked.
Full image on Astrobin.
https://www.astrobin.com/403480/?nc=user

[wornish]

Thought I would share this.

It was done by an amateur astrophotographer in a small town in Wiltshire.

If anyone needs convincing to try out astrophotography just watch this.

The background music was done by his local choir.

A Cosmic Adventure - YouTube

A Cosmic Adventure - YouTube