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My latest & best astrophotographs

This page has two main sections. First some links to the photos I consider to be among my best so far. Then a log of latest photos, in reverse chronological order. I gradually move the latest photos to relevant other pages and leave a link.

Some of my best:

Telescopic photo of M42 nebula in Orion

Larger versions of some of my astrophotos may be found on my Flickr page.

MY BOOK

The Dark Skies of the North Pennines
An amateur photographer's delight

Helping digital camera owners every-
where to discover for themselves the
wonders of the night sky.

More details & sample pages

ASTROSCAPES

Some creative images to encourage photographers to get out there at night and be amazed.

News, 2012 Sep 20

I am delighted that my image of Comet C/2009 P1 Garradd taken on March 19 was HIGHLY COMMENDED in the 2012 Astronomy Photographer of the Year Competition. It was in the Exhibition at the Royal Greenwich Observatory until 2013 Feb 13 and appears in the book of the event.

 

 2016 Feb 14

 A note about narrowband filters

My recent photos using narrowband filters on an unmodified Canon DSLR have been more successful than I had hoped. So I want to make clear why it works so well and why, in my opinion, it is better than getting the camera modified to extend its red range.

As I have described elsewhere, the pixels in a DSLR all have coloured filters in front of them. 25% of them have a red filter, that allows through only light towards the red end of the spectrum.

Light pollution, reflecting off dust in the air, covers the whole spectrum (all wavelengths) as shown in the following diagram.

The filters in front of the red pixels integrate (more accurately, convolve with) the total shaded area under their response curve. If we are looking at a part of the sky that is emitting H-alpha light, the H-alpha peak is only an insignificant part of that shaded area and so is lost.

In the next diagram we see what happens when a narrowband filter, designed to be centred on the H-alpha line, is also in the optical path. It cuts out all but the H-alpha peak, plus pollution in that range. So the hydrogen peak is now a significant part of the detected light.

In Canon cameras (and probably other makes too) the response curve for the pixel red filters is down to about half its peak value at 656nm (the H-alpha wavelength). So it is necessary to use longer exposure times to detect H-alpha. If I had modified my camera to extend its range towards infrared I would be able to reduce exposure by about half but I would still need the narrowband filters, as I hope is clear from my diagrams.

The filters are expensive but so is camera modification (unless you do it yourself, but that is risky). Filters alone have more effect than modifying the camera so I decided upon that route and I am pleased with the results so far (see the examples below).

I also have a narrow (8.5nm) filter for doubly ionised oxygen (OIII). Many nebulae emit the 2 lines from OIII at 495.9 and 500.7nm which this filter is designed to cover. I have used it in a few of my images, such as of the Veil Nebula below.

It would be nice to get a third colour. The next most useful emission line is from singly ionised sulphur (SII) but it lies further towards the infra-red, at 672nm. That suggests camera modification would be necessary. However, even if the IR cut filter were to be removed from my DSLR I would still be limited by the red Bayer filters which cannot be removed. I think the best way forward then would be to get a monochrome CCD camera. (A colour CCD camera would have Bayer filters and would therefore offer no improvement.)

Having 3 colours would make it possible to use a different one of the RGB colour bands for each of them. One possibility would be to show SII in red, H-alpha in green and OIII in blue. Such things are done for images from the Hubble Space Telescope, for example. Some people call this the Hubble Palette but there are many variations, assigning different wavelengths to different bands for display. This is not just done for a pleasing appearance; it can help to make fine details visible.

 

 2016 Feb 10

 Earthshine

The "old Moon in the new Moon's arms" was very easy to see at dusk this evening. This is just a single frame with the camera set to automatic.

Canon EOS 5D MkIII + Canon 200mm f/2.8 lens on HEQ5 mount
f/2.8 ISO 800, 1/8s 2016 Feb 10 at 17:59:33

 

 The Heart & Soul nebulae

Another H-alpha photo taken with unmodified DSLR from light-polluted suburbia. I have combined this with a shorter set of exposures in normal light for the foreground stars. The Heart Nebula (IC1805) is conspicuous. Above it is the Soul Nebula (Westerhout 5). Bottom left is the Perseus double star cluster (NGC 869 & 884).

Canon EOS 5D MkIII + Canon 200mm f/2.8 lens on HEQ5 mount, not guided
Baader 7nm H-alpha filter f/3.9 ISO 12800, 64 x 64s + 32 x 128s = 136.5 minutes
+ no filter f/2.8 ISO 3200, 13 x 16s = 3.5 minutes
2016 Feb 10 at 19:01:05 - 23:01:31 UT Processed with GRIP
From Whitley Bay 55.1N 1.5W 10m asl. Suburban, significant light pollution (6.5 Bortles)

 

 Jupiter with no telescope

Jupiter is currently very bright in the eastern sky after about 10pm.

Just to demonstrate that a telescope is not needed for seeing the Galilean moons of Jupiter, this photo was taken with a 200mm lens on an HEQ5 mount (motor driven at fixed sidereal rate). Binoculars should suffice for visual observations.

Canon EOS 5D MkIII + Canon 200mm f/2.4 lens on HEQ5 mount
f/5 ISO 400, 8s 2016 Feb 10 at 23:05:08

This is a 100% view cropped from the centre of the photo.

From left to right in the photo the 4 moons are Callisto, Europa, Io and Ganymede. I was able to identify them on my own Jupiter satellite calculator page.

The spikes around Jupiter are due to the iris diaphragm in the lens. I should have left it fully open at f/2.8.

 

 2016 Feb 2

 Nacreous clouds

This was photographed at 17:02 GMT with the camera set to automatic. The Sun had set at 16:43 and civil twilight ended at 17:23 (according to The Photographer's Ephemeris for my location). So the Sun was nearly 3 degrees below the horizon which accords well with the Wikipedia description of this type of cloud. See polar stratospheric cloud.

Wispy clouds continued through the night, making the following image difficult.

   

 Hydrogen in Orion

Another image obtained from light-polluted suburbia with an unmodified Canon DSLR by using a narrowband H-alpha filter.

Canon EOS 5D MkIII + Canon 50mm f/1.4 lens on HEQ5 mount, not guided
Baader 7nm H-alpha filter f/2.8 ISO 12800, 123 x 64s = 131.2 minutes
2016 Feb 2 at 18:29:39 - 22:32:20 UT Processed with GRIP
From Whitley Bay 55.1N 1.5W 10m asl. Suburban, significant light pollution (6.5 Bortles)

To the left is the Rosette Nebula in Monoceros. Clearly visible on the left side of Orion is the main part of Barnard's Loop. Hydrogen around the Flame and Horsehead nebulae is bright, as is M42. Fainter is the disc (sphere?) of hydrogen around Orion's head.

The brightness along the bottom of the picture is from continual cloud/haze near the horizon. Orion never rises very high in the sky here.

 Combined image

Here I have combined the above H-alpha image with a normal light fixed-tripod image I took on 2015 Feb 9 using the same lens but my previous camera:

I used GRIP to align the 2 images accurately and add them together, 50% of each.

 

 2015 Nov 19

The Moon was just past first quarter and clouds kept coming across the sky but nevertheless I managed to get the following 2 whole-constellation views with my unmodified DSLR by using narrow-band filters.

This time I have drawn lines for the constellation shapes because the camera detects so many more stars than the naked eye that the shapes get lost.

 Nebulae in Cassiopeia

Canon EOS 5D MkIII + Canon 50mm f/1.4 lens on HEQ5 mount, not guided
Baader 7nm H-alpha filter f/2.8 ISO 12800, 32 x 64s = 34 minutes (red channel)
Baader 8.5nm OIII filter f/2.8 ISO 12800, 10 x 32s = 5.3 minutes (green & blue)
2015 Nov 19 at 20:58:10 - 22:19:00 UT Processed with GRIP
From Whitley Bay 55.1N 1.5W 10m asl. Suburban, significant light pollution (6.5 Bortles)

At the bottom is the Heart Nebula and I am delighted that it shows up so clearly. To its right is the Perseus double star cluster. Below the middle of the W is NGC281, the PacMan nebula. I have not yet identified the nebulae in the upper half of the image.

 Cygnus, the Swan

Canon EOS 5D MkIII + Canon 50mm f/1.4 lens on HEQ5 mount, not guided
Baader 7nm H-alpha filter f/1.8 ISO 12800, 35 x 64s = 37 minutes (red channel)
No filter f/1.8 ISO 1600, 6 x 8s = 48 seconds
2015 Nov 19 at 20:49:01 - 20:49:50 UT Processed with GRIP
From Whitley Bay 55.1N 1.5W 10m asl. Suburban, significant light pollution (6.5 Bortles)

This is just another view similar to those from recent photos, below, except that it luckily covers the whole of the main part of Cygnus. I have inverted the image (north is bottom left) to make clearer the reason why the constellation is said to represent a swan.

 

 2015 Nov 6

A clear evening without the Moon. Not perfectly clear: I could only make out 2 stars in the Pleiades and M31 was not detectable as it sometimes is from here in suburbia. However I was able to get some very decent (amazing) results using narrow band filters in front of my unmodified Canon 5D3.

 The Veil Nebula (H-alpha & OIII)

Colours as shot: red for hydrogen, green and blue for oxygen.

Canon EOS 5D MkIII + Canon 200mm f/2.8 lens on HEQ5 mount, not guided
Baader 7nm H-alpha filter (50mm diam.) → f/3.9 ISO 25600, 65 x 64s = 69 minutes (red channel)
Baader 8.5nm OIII filter (65mm square) → f/3.0 ISO 12800, 65 x 64s = 69 minutes (green & blue)
2015 Nov 6 at 18:51:06 - 21:51:58 UT Processed with GRIP - see note below
From Whitley Bay 55.1N 1.5W 10m asl. Suburban, significant light pollution (6.5 Bortles)

My previous attempts to photograph this nebula from the darkness of Weardale using a 10inch Newtonian pale into insignificance compared to this. I am really just discovering the delights and power of narrow band filters.

 

 Hydrogen clouds around Gamma Cygni

After the Veil I turned the camera a few degrees to see what the region around Gamma Cygni looked like through the 200mm lens. I was amazed:

Canon EOS 5D MkIII + Canon 200mm f/2.8 lens on HEQ5 mount, not guided
Baader 7nm H-alpha filter (50mm diam.) → f/3.9 ISO 25600, 21 x 128s = 45 minutes
2015 Nov 6 at 22:25:15 - 23:14:49 UT Processed with GRIP - see note below
From Whitley Bay 55.1N 1.5W 10m asl. Suburban, significant light pollution (6.5 Bortles)

That is only part of the view. Gamma Cygni is the bright star near the centre. North is diagonally up and right. In the bottom left the Crescent nebula (NGC6888) is clearly visible.

I did also take an OIII exposure. Only the crescent nebula and a small area to its north showed up in OIII.

 

 A note on processing

These images were processed by my GRIP program using its "medianising" method. This is a 2-stage process.

  1. "Batch/Astro/Astro warp/shift onto common basis" aligns the images but does not stack them. Instead it saves them in new files (FITS or TIFF, depending on what you input).
  2. "Batch/Astro/Create median pixels image" goes through those files (in multiple slices, depending on how much RAM you have available) and for every pixel it makes a list of its values in all the images, sorts the list and takes the median value. It builds one image containing the median values.

On my laptop with 8Gbytes of RAM (not unusual these days) the process only takes about twice as long as more straightforward stacking.

This produces a better result than stacking because it exploits the fact that the drive in the equatorial mount is not perfect: images can be displaced from each other by a few pixels. GRIP even shows a graph and spreadsheet of the displacements during the process. Taking the median value for each pixel avoids extremes such as are caused by hot pixels, which are thereby eliminated altogether (not just watered down as would occur in stacking). This also tends to reduce fixed-pattern noise from the detector which can become troublesome at high ISO values such as 25600.

I saved each result as 16-bit TIFF and then opened it in Photoshop (CS4) mainly to use unsharp masking (Filter/Sharpen/Unsharp mask). I use the biggest possible radius (250px) at 100%. This enhances details while lowering large-scale variations. Photoshop's implementation of this tends to make the image brighter so that some highlights may burn out, in which case it is necessary to darken the image before unsharp masking, then perhaps brighten it again afterwards.

No dark frames or flat frames were used. I have written a page about that here.

Another tip

Have a cheap hairdryer available when taking the photos! In the few seconds between exposures blow it gently over the front of the lens or filter. This prevents dew forming (and frost on colder nights).

 2015 Oct 24

This evening was frustrating: the first forecast clear night for ages but it turned out to be plagued by wisps of high thin cloud. A two-thirds Moon was not likely to help either, except that I am using narrow-band filters. The temperature fell so rapidly that I could not keep the filters free from dew and I had to give up after a couple of hours. Half the exposures taken turned out to be useless. Despite all this I made a promising start on the following.

 The Veil Nebula (H-alpha & OIII)

NB: From light-polluted suburbia with an unmodified Canon DSLR.

For getting larger images of nebulae with a fast lens I now have a Canon 200mm f/2.8 prime lens, bought secondhand. I now also have 2 narrow band filters:

I managed to get short sequences through each filter to produce the following when stacked in GRIP.

Hydrogen:

Canon EOS 5D MkIII ISO25600
Canon 200mm f/2.8 lens at f/3.9
Baader 7nm H-alpha filter (2 inch diam.) in front of lens
HEQ5 mount, not guided
28 x 64s = 29.9 minutes total exposure
2015 Oct 24 at 19:04:26 - 19:43:07 UT
From Whitley Bay 55.1N 1.5W 10m asl. Suburban, significant light pollution (6.5 Bortles)

Oxygen:

Canon EOS 5D MkIII ISO12800
Canon 200mm f/2.8 lens at f/3.0
Baader 8.5nm OIII filter (62mm square) in front of lens
HEQ5 mount, not guided
2 x 64s + 10 x 32s = 7.5 minutes total exposure
2015 Oct 24 at 20:30:27 - 20:41:28 UT
From Whitley Bay 55.1N 1.5W 10m asl. Suburban, significant light pollution (6.5 Bortles)

Combining those two images by putting hydrogen as the red channel and oxygen as green, with no blue, produces this coloured image:

All I can say is that, considering how short the total exposure times were, this is a good start and I should easily be able to do better when there is a properly clear night.

 

 2015 Oct 1

 Hydrogen in Cygnus

Continuing my experiments with a narrow band filter, this was again taken from a light-polluted site with an unmodified DSLR. Furthermore the Moon was up - gibbous, only 2.5 days past Full, but about 90° away from my target area.

Canon EOS 5D MkIII ISO12800
Canon 50mm f/1.4 lens at f/1.8
Baader 7nm H-alpha filter (2 inch diam.) in front of lens
HEQ5 mount, not guided
65 x 64s = 69.3 minutes total exposure
2015 Oct 1 at 20:04:45 - 21:36:46 UT
From Whitley Bay 55.1N 1.5W 10m asl. Suburban, significant light pollution (6.5 Bortles)

We see here a map of neutral hydrogen in the northern part of the constellation of Cygnus.

The brightest star in the top right quadrant of the image is Alpha Cygni. To the left of that and slightly up lies the North America Nebula and the Pelican Nebula, as I photographed in more detail last month (below). Down (southwards) from Alpha Cygni the next bright star, Gamma Cygni, has further hydrogen clouds around it and the hydrogen extends further southwards, along the Milky Way.

Clearly visible to the left (eastwards*) lies the Veil Nebula. This is the remnant of a supernova explosion several thousand years ago.

*Remember that east and west are reversed when we look upwards, as compared to looking down at a terrestrial map.

I am absolutely delighted that I am able to do this with my unmodified DSLR but I think this may upset some people who have paid to have their cameras modified. As I have noted before, the H-alpha emission line lies on the downward slope of the camera's built-in IR filter, such that the camera is only half as sensitive at this wavelength - ie, 1 photographic stop (1 EV) down - and we can compensate for that by increasing ISO sensitivity and/or exposure time.

Notice that some stars appear to be white, despite the narrow red filter. The same occurred on the previous image (Sep 6, below). It is because the brightest stars overfill their pixels with electrons. Charge then overflows into neighbouring pixels. The neighbours of red pixels on the detector are green and blue. So when the RAW image is interpolated to make an RGB image white is formed by the overflows.

I also took the filter away from the lens and continued, to get a shorter sequence in normal light (17 x 8s at ISO3200). The result has been superimposed using GRIP to show the stars better:

A larger version can be seen on my Flickr page (click on the thumbnail image there).

Exposure control was done by APT software running on my laptop, connected to the camera by a USB cable (5m boosted cable as an extension to Canon's supplied USB cable). I recently upgraded to the latest version of APT and used its focussing aid to get a sharp focus on the stars, which was easy to use and worked very well. I thoroughly recommend APT.

The focussing aid in APT looks like this:

The background here is a live image (but several frames integrated, for brightness). The dialogue is dragged over a bright star and a graph of its profile is shown along with some measurements. FWHM is Full Width at Half Maximum (of the profile) and that measurement needs to be minimised. That can be done quite effectively by slowly turning the focus ring on the lens (set to manual) while holding the laptop alongside the camera. Then, being already conected to a long USB cable, I move the laptop indoors, where I can sit in comfort to set the exposures going and watch each result.

I always put some tape over the focus ring when focus is reached, so it cannot move. Heavy zoom lenses tend to slip when looking upwards: tape the zoom ring too.

 

 2015 Sep 6

 H-alpha light from NGC7000

This was taken from a light-polluted site with an unmodified DSLR.

Canon EOS 5D MkIII ISO25600
Canon 100-400mm L IS lens at 200mm, f/5.0
Baader 7nm H-alpha filter (2 inch diam.) in front of lens
HEQ5 mount, not guided
123 x 32s = 65.6 minutes total exposure
2015 Sep 6 at 21:17:49-22:29:34 UT
From Whitley Bay 55.1N 1.5W 10m asl. Suburban, significant light pollution (6.5 Bortles)

Having lost my dark observing site in the North Pennines, I am experimenting to see how difficult deep-sky objects might still be photographed from light-polluted suburbia. I purchased a Baader narrowband H-alpha interference filter. It transmits only a 7nm wide band around the Hydrogen-alpha line at 656nm. These filters are produced in circular holders designed to fit in front of astronomical eyepieces and so they have diameters of either 1.25 inches (3.175mm) or 2 inches (5.08mm). I obtained one of the larger size and cut some thick mounting card to hold it in the 77mm diameter filter ring of a lens (I have 2 lenses with that size filter ring).

This year I have also upgraded my camera from 5D Mk2 to 5D Mk3. That gives me 2 further stops of sensitivity: the maximum non-extended ISO setting is 25,600. So in this first experiment I have used half-minute exposures at f/5 and that highest ISO setting.

I am pleased to see that although the H-alpha line falls at the edge of Canon's detector range, where the sensitivity is already reduced by a half (as I investigated here), I can photograph not only the main part of the North America Nebula (NGC7000) but also the neighbouring Pelican Nebula (IC 5067 & IC 5070) and other hydrogen clouds to the south of those. All without modifying my camera and, furthermore, from light-polluted Tyneside.

After taking the H-alpha exposures to make the image above, I carefully removed the filter from in front of the lens and took some more exposures in normal light. As expected the light pollution prevented the nebulae from being seen in the result. However after further processing to enhance it I obtained the following image.

Canon EOS 5D MkIII ISO6400
Canon 100-400mm L IS lens at 200mm, f/5.0
HEQ5 mount, not guided
8 x 32s = 4.3 minutes total exposure
2015 Sep 6 at 22:30:41-22:34:49 UT
From Whitley Bay 55.1N 1.5W 10m asl. Suburban, significant light pollution (6.5 Bortles)

Most of the nebulosity visible here is due to gases other than hydrogen, so the shapes are different.

Compare with my earlier photos of NGC7000 here.

I then used GRIP to align the 2 images above and add them together, 50% of each. Here is the result:

Here is a picture showing how I fitted the filter to the lens:

I carefully cut circles in mounting card with a knife to get snug fits both of the filter in the card (it screws in) and the card into the filter thread on the front of the lens.

 Fewer photos

 

New images on this page are much less frequent than they used to be. The reason is that I have given up my observatory site in Weardale (as of 2015 March). I have donated my observatory and telescope to a project being run by the North Pennines AONB management team, to provide a public observing site within the AONB. That will probably be located at Allenheads. More information should be available on the AONB web site in due course.

I hope to continue with some astrophotography. I still have an HEQ5 mount for my camera, the lenses for which range from 15mm (fish-eye) to 400mm. I will continue to encourage other photographers, partly by demonstrating what can be done without telescopes or guiding systems.

 

 2015 March 20

 Partial solar eclipse

The weather in Whitley Bay improved enough to enable the eclipse to be seen and photographed through the clouds, from just after maximum eclipse. No filters were needed, the camera was set to P (mostly automatic, aperture priority).

09:41

09:43

09:44

09:45

09:48

09:50

09:56

09:59

10:04

10:10

10:14

10:21

 

 2015 February 8

 Orion

Canon EOS 5D MkII ISO6400
Canon 50mm (f/1.4) lens, f/2.8
Fixed tripod, 99 x 10s = 16.5 minutes total exposure
2015 Feb 8 at 21:44:19-22:03:45 UT

This is another example of what can be done from a dark site with just a camera on a fixed tripod.

Near the top left of this image is a curious feature which I had never noticed before: a thin dark nebula that wraps snake-like around Betelgeuse. I can find no mention of it in any catalogues or on charts although I can see it in other photographs of the same area. The following is an enlargement of that part of the photo.

Dark nebulae like this are clouds of dust. But what could have caused this one to form such a narrow strip? If it lies at about the same distance from us as Betelgeuse then one possibility might be that wind blowing out from the star (as stars are known to do) could have compacted the cloud in this way. To see whether this might be feasible I used GRIP to measure the angular distance of the nebula from Betelgeuse. At its nearest, on the right, it is 1.1° from the star but generally it is more like 2.5° away from it. At the distance of Betelgeuse (640 ±140 light years) that would mean the nebula is generally 28 ±6 light years away from the star. I doubt whether a stellar wind could have much influence over such a distance. However, Betelgeuse is nearing the end of its hydrogen fuel supply and therefore may be subject to outbursts. It is expected to explode as a supernova within the next million years.

 

 2014 Nov 23

 The Milky Way between Cepheus and Cygnus

My best shot so far of this interesting region, taken with the Canon 50mm f/1.4 lens. I now have interesting comparisons between this lens and the much cheaper 50mm f/1.8 lens, which I will show. There are both pluses and minuses for the f/1.4 lens. More...

Canon EOS 5D MkII
Canon 50mm (f/1.4) lens at f/2.8
HEQ5 mount unguided
(ISO3200, 64 x 32s) + (ISO800, 17 x 32s) = 43.2 minutes total exposure
2014 Nov 23 at 18:55:26 - 19:58:39 UT
From Rookhope 54.8N 2.1W 330m asl. Rural, almost no light pollution (3 Bortles)

This photo covers a sky area measuring 27.0 x 39.6 degrees. At the top (due north) is part of the constellation of Cepheus and the bottom covers the northern part of Cygnus. The bright pinkish area below the centre is the North America Nebula (NGC7000, see my other photos of this).

 

The Garnet Star

Above the centre, at the tip of the reddish part of the image, an orange star really stands out. This is μ Cephei, known for a long time as the Garnet Star because of its intense colour when viewed in telescopes. I find it interesting that it stands out so well in my image. It lies on the northern edge of a faint nebula catalogued as IC1396 (which I must try to photograph telescopically). Here is an enlargement of that part of my image:

Exposure details as above

 Comet C/2014 Q3 (Borisov)

Image moved to C/2014 Q3 page.

 Comet 108P/Ciffreo

Image moved to 108P/Ciffreo page.

 2014 Oct 1

 Comet C/2014 E2 (Jacques)

Image moved to C/2014 E2 page.

 The Milky Way in Cygnus

Canon EOS 5D MkII ISO6400
Canon 50mm (f/1.8) lens, f/5.6
HEQ5 mount unguided, 44 x 64s = 46.9 minutes total exposure
2014 Oct 1 at 22:15:46 - 23:10:21 UT
From Rookhope 54.8N 2.1W 330m asl. Rural, almost no light pollution (3 Bortles)

Compare this with the image below taken on 2104 Aug 24. That image was taken on a fixed tripod and so exposures were limited to 10s each to avoid trails. Today's image was on a motorised tripod and so each exposure was 64s long but the aperture has been stopped down in order to make the focus sharper. Unfortunately the lossy JPEG compression necessary for putting this on the web makes the detail much less good than in the full sized original which, like most of my original images, is printable at poster size (A2).

 2014 Aug 24

Another clear night! I decided to continue the demonstration imaging from yesterday but this time using a cheaper lens: Canon 50mm f/1.8 (the cheap one in a plastic casing). The very low f-number of this lens means much fainter details can be captured with short exposures (I am still using a fixed tripod, no telescope, no guiding, no darks or flats). The down-side of such an aperture is that focussing is quite critical. I focussed on Vega, as yesterday, but I had to tape the focus ring to stop it slipping. On this cheaper lens the focussing ring is quite flimsy.

 The Milky Way in Scutum

Image moved to Milky Way page.

 Comet C/2014 E2 (Jacques)

Image moved to C/2014 E2 page.

 The Milky Way in Cygnus

Image moved to Milky Way page.

 2014 Aug 23

An unexpected clear night after rain. I decided to take some more demonstration shots to show what can be done on a fixed tripod: NO telescope, NO guiding, NO dark or flat frames. Individual exposures had to be short to avoid star trails. I used my Canon 24-105mm zoom lens on Canon EOS 5D Mk II camera. I focussed on bright stars (Arcturus and Vega) using the camera's live view magnified by 10.

 The Plough in twilight

Resulting images moved to Ursa Major page.

 Comet C/2014 E2 (Jacques)

Image moved to C/2014 E2 page.

 

 The Milky Way in Cepheus

Canon EOS 5D MkII ISO6400
Canon 24-105mm L IS lens at 32mm, f/4.8
Fixed tripod, 34 x 8s = 4.5 minutes total exposure
2014 Aug 23 at 21:33:57 - 21:40:06 UT
From Rookhope 54.8N 2.1W 330m asl. Rural, almost no light pollution (3 Bortles)

This is the stretch of Milky Way from Casssiopeia through Cepheus to Cygnus. I had some trouble with the zoom shifting due to the weight of the lens when looking up. I should have taped it but didn't. The result was that I could not stack the full set of images I took. So the result is not as good as I hoped.

 2014 Mar 23

A truly clear moonless night at last. But there was evidently significant dust high in the atmosphere because the background of all my raw images was quite brown, due to reflected distant light pollution.

 Spiral galaxy M101

Image moved to M101 page.

 Comet 290P/Jager

Image moved to 290P/Jager page.

 The Rosette Nebula, wide field view

Image moved to Rosette Nebula page.

 2014 Mar 22

 The Rosette Nebula, NGC 2237 etc

Image moved to Rosette Nebula page.

 2013 Nov 19

 Comet C/2013 R1 (Lovejoy)

Image moved to C/2013 R1 page.

 2013 Nov 4

 Comet 154P/Brewington

Image moved to 154P page.

 NGC 1555, Hind's variable nebula

Image moved to NGC1555 page.

 

 Satellite trail & atmospheric turbulence

As often happens, I omitted from the NGC1555 stack a frame that was spoilt by a satellite trail. The satellite was clearly rotating because it reflected a varying amount of sunlight:

An enlargement of part of the trail (so 1 camera pixel = 1 screen pixel here) shows how the image of the path was affected by atmospheric turbulence:

 2013 Oct 29

The first clear moonless evening here for over a month!

 M31, the Andromeda Galaxy

Image moved to M31 page.

 2013 Sep 14

Two comets that have been bright but are now receding from us. I managed to photograph them despite a bright gibbous Moon.

 C/2011 L4 (Pan-STARRS)

Image moved to C/2011 L4 page.

 C/2012 F6 (Lemmon)

Image moved to C/2012 F6 page.

 

 2013 Aug 16

 Nova Delphini 2013

A nova was discovered in Delphinus on August 14. It has risen to about magnitude 4.9 which makes it the brightest nova since 1999. I managed to get a set of photos between clouds:

Canon EOS 5D MkII, ISO 1600
100-400mm lens at 150mm f/5.6 HEQ5 mount
23 x 32s on 2013 August 16 at 22:32:17-22:41:09 UT
From Whitley Bay 55.1N 1.5W 10m asl. Suburban, significant light pollution (6.5 Bortles)

 2013 Aug 12

 Perseid meteors

See Perseid meteors page.

 2013 Apr 6

 273P/Pons-Gambart

Image moved to 273P page.

 C/2011 L4 (Pan-STARRS)

Image moved to C/2011 L4 page.

 2013 Apr 3

At last! A clear night and no moon. So I shot a couple of comets. There would have been more but by midnight the temperature was below -10C so I could not continue. We still have snow lying, most of which fell 3 weeks ago.

 63P/Wild

Image moved to 63P page.

 C/2012 S1 (ISON)

Image moved to C/2012 S1 page.

 2013 Mar 16

 C/2011 L4 (Pan-STARRS)

Image moved to C/2011 L4 page.

 2013 Mar 15

 C/2011 L4 (Pan-STARRS)

Image moved to C/2011 L4 page.

Later I headed out to try to photograph the comet which is predicted to become very bright in November: C/2012 S1 (ISON). It is currently on the borders of Gemini and Auriga and may just be bright enough to photograph. However, having got set up and navigated almost to the target, the skies clouded over completely and that was that. Typical of weather for the whole of this winter.

 2013 Feb 17

 The Moon in daylight

Image moved to the Moon page.

 2012 Nov 17

 NGC281

Image moved to NGC281 page.

 2012 Nov 5

 

 Central Cassiopeia

I plan to photograph NGC281 but I wanted first to put it in context, so this photo shows the central part of Cassiopeia, framed by 3 of the 5 stars that form the W shape: alpha, gamma and delta:

Image moved to Cassiopeia page.

That sequence was stopped by the telescope running into a tripod leg, due to Cas being vertically overhead. So I moved the telescope a bit and it happened to include the double cluster in the field of view, so I proceeded to take some more exposures.

 The Double Cluster & the Heart Nebula

It was pure chance that the field also included the Heart Nebula (IC1805), which I will have to take a closer look at another time.

Image moved to Heart Nebula page.

Then I was stopped by the sky clouding over, as so often happens this year.

 2012 Oct 21

 

 Focus trouble

I had a disastrous photographic session but in the process I learnt something. Camera lenses have to be left a long time to adapt to the cold. Much longer than I have been doing for camera body plus Newtonian telescope.

A useful tip when focussing a telescope by eye is that at the best focus you can see the most stars. The faintest stars become invisible again when the focus drifts out. Well I was pleased to discover that the same applies to the algorithm I devised for detecting stars in GRIP. I am not about to divulge the details of my algorithm. Suffice it to say that it is very fast and it does not try to correlate Gaussian shapes with star profiles (which may be accurate but would take much longer).

When stacking exposures, GRIP logs the number of stars it detects in each frame. Unfortunately I do that processing the day after an observing run. Otherwise I would have spotted that my frames were drifting out of focus on this occasion, as shown by this graph (made from the CSV file that GRIP created after stacking, the next morning):

What happened was this. I set my camera piggy-back on my Newtonian in order to use the latter to point towards the centre of the Veil Nebula in Cygnus. I hoped to capture the whole extent of the nebula which is much larger than will fit into a telescopic field of view. So I was using a 100-400mm Canon lens. I focussed carefully on Jupiter and its satellites. Now, the other new factor was that I was trying out Ivaylo Stoynov's mostly excellent software, APT (Astro-Photography Tool). APT uses Canon's SDK (Software Development Kit) to control the camera (which, as an individual rather than a company, I am unable to get for integration with GRIP). APT enables me to sit in a heated shed next to my cold observatory, drive the camera via a USB cable (5m, boosted) and see each frame on my laptop immediately after capture. Or at least, that's the theory. Unfortunately there was a bug in APT which meant that after a while it was not updating the image display. I let it run for over an hour, not realising that the camera was drifting out of focus. The graph clearly suggests that the cause was temperature adjustment.

I conclude that for this kind of photography I must put the camera out in the observatory an hour and a half before starting.

I reported the bug to Ivo and he responded quickly to investigate and fix the bug. I also persuaded him to add a new feature, optionally converting the RAW file to 16-bit TIFF immediately after capture. Because this uses Canon's library I believe this will do a better job than any third-party software and it saves me having to set up a batch run in DPP (Canon's image processor that comes free with every EOS camera) the next morning.

 M45 (Pleiades)

Having realised that my first sequence of the night was useless I decided to try again but was limited by the sky clouding over after a while. So here are the Pleiades again, but with the 100-400mm zoom lens at 400mm.

Image moved to the M45 page.

 2012 Oct 16

 NGC7000 & IC5067/70

After a day of rain the skies became very clear, so I tried a closer view of NGC7000.

Image moved to NGC7000 page.

 2012 Oct 9

 The Milky Way in NE Cygnus

Image and description moved to NGC7000 page.

 

 2012 Sep 14

 The Milky Way through Cygnus from a fixed tripod

Image moved to the Milky Way page

 2012 Sep 11

 Andromeda Galaxy (M31)

Image moved to the M31 page.

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