It’s been a sparse few months for imaging. As well as the short nights of the summer months I’ve also had a few problems with my DSLR, plus the roads around my house have all been fitted with tall bright LED lights (see photo below, showing how much bigger they are) rendering my light pollution filter useless and limiting me to subs <1min. To fight back I’ve invested in the new version of the IDAS filter which offers some relief, plus a second hand Canon 600d with the IR filter removed. Monday was my first chance to use it, and I decided to go for M31 for the purposes of comparison with previous camera and streetlights. After setup I had an hour to try it out and the results are quite promising- I think I’ve gained more from the new kit than I’ve lost from the LEDs. There are some further things that I can do to improve it (I think I can get away with longer exposures, plus I want to try and make a cooling unit for it)- but altogether I’m quite pleased. It’s 20x 180s exposures on a 130 pd-s, with guiding, plus dark, bias and flats.
Whilst the imaging rig was doing its stuff I went for some instant gratification with the Dob. Whilst the LED lighting has hurt the imaging it seems to be better for the visual. At a RAG meeting a while back there was discussion of how counting stars in Pegasus would give you a good indication of your light pollution levels. I went home and found I had a depressing big fat zero. Although the new lights are brighter, they are better directed and I can now see 3 or 4 (faint) stars. This realisation was a good start to an enjoyable session- transparency seemed pretty good, and I doubt there’ll be another session this year where it’s too warm for a jacket. From the observing log:
M71 – Struggled to get my eye in to start with and I found it a tricky find, but satisfying once in.
M15 – Really bright central core and with a ring of resolved stars around it covering around a quarter of the eyepiece at 220x
M2 – Was tighter and not quite so bright or widespread but still a nice view
M52 – Gorgeous open cluster- 30-40 bright stars and many much fainter ones. Tried it at 220x, 70x and 45x and the middle magnification was the best- really filling the view. Highlight of the night.
NGC7789 – Caroline’s Rose – Another nice open cluster- but quite faint, and I couldn’t really see the rose. Maybe it’s like one of those Magic Eye pictures.
M103 – A nice triangular shaped with a lovely red quite central in the Eyepiece.
Monday night’s a bit early in the week to stay up late, and the only downer was packing up as the skies were getting better still. At least I was heading to bed with a full memory card ready for the clouds and rain that have dominated the remainder of the week…
Another superficially nice night, but the Mars seeing was pretty poor, and I got clouded out quite rapidly.
Before looking at Mars I had a go at M20, the Trifid nebula, in Sagittarius. This was pretty low at about 11 degrees elevation for a dim DSO, necessitating a fair amount of processing to get anything reasonable.
Mars was like a wobbly jelly. This time I tried a X3 barlow. The ADC is clearly doing its stuff, but it won’t compensate for poor seeing! The Hellas basin was obvious visually – easy to mistake for the S. polar cap!- and Syrtis Major was just about in view.
Having been seriously impressed with Neil’s planetary images, i have an ADC on order!
Meanwhile, I had another go at Saturn last night. Had it not been for Neil’s images, I would have been quite pleased with this one! Best I’ve managed this apparition!
I then did a composite exposure of the visible moons.
While waiting for Mars to rise to an appropriate position, I vistited these 2 planetary nebulae, NGC 6818 in Sagittarius and NGC 6781 in Aquila.
Eventually, Mars became visible,and I tried this image, bearing in mind Mars’s altitude was only about 11 degrees. As I’m sure you know, Mars is currently covered by a dust-storm, hence the lack of visible surface detail.
There did seem some vague hint of detail so here is the image with an extreme contrast stretch, followed by a screenshot of Mars from “Stellarium” for comparison. (Stellarium shows an accurate depiction of the surface facing us – a useful resource)
This image combines a colour image from 7 July with a Ha one from 21 June. Both taken with my 130P-DS and Canon 450D which is ‘astro-modified’ and cooled. The colour is binned 2×2 and the Ha is on top as ‘luminance’ at about 45% transparency. Very chuffed with the star colours, who needs a ‘frac? 🙂
This time of year since, it does not get really dark, it isn’t easy to image DSOs. However, Jupiter’s Great Red Spot was supposed to be transiting at about 12:40 so I set up to see if I could get an image. I have found it difficult to get a decent image of Jupiter this year because of its low altitude, and last night was no exception. After some extensive processing, you can at least see the red spot, and if you look hard there are other blobs and features. Coudn’t see any sign of Nick’s GRS streamer though. I managed to miss Callisto too – it is off-stage to the left!
Globulars seemed to be a reasonable bet in the circumstances, so here is M10 and M12.
Then on to NGC 6309, a planetary nebula (the Box nebula)
Finally on to M107 a small globular in Ophiuchus.
I also observed NGC 5746, 5846 and 5850, but the images aren’t really worth posting.
Then it started to get light – – –
After a bit more work processing NGC5746, I managed to recover something, even though it is not brilliant. Just shows, you can see DSOs in the summer twilight!