This is NGC4631 and NGC4656-7 better known as the Whale and Hockey stick galaxies. Imaged over several nights 21-25th April 2022, I managed only a few hours total due to bad weather.
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This is NGC4631 and NGC4656-7 better known as the Whale and Hockey stick galaxies. Imaged over several nights 21-25th April 2022, I managed only a few hours total due to bad weather.
This is a “first light” image taken with my new wide-field setup.
Here we have the star Sadr in the constellation of Cygnus. Using narrowband Ha (56mins) and Oiii (30mins) filters I’ve captured the glowing dust in the region surrounding the star. Not bad for a first image. This widefield shot shows Sadr in the middle surrounded by nebula (IC 1318) but also included is the so-called propeller (top-left), many dark regions, NGC6914 a blue reflection nebula (very faint, middle left region) and the Crescent nebula (NGC 6888, top right).
This lens is fantastic for grabbing photons quickly from a very wide field of view. I plan many more sessions with it and will probably revisit this area when we have astronomical dark back in August.
I’ve owned the 135mm for over 2 yrs but just didn’t have the time to put together a rig for it. I’ll make a separate blog entry on the construction of the mount.
I’ve taken a shot at Messier 51 again. Compared to Messier 51 and first light for my Orion Optics 250mm rebuild from last year it is more successful:
Conditions were much better and my guiding is considerably better with <> 0.6 total rms. With careful processing I am able to extract detail at the limit of the scope and camera performance when seeing is good, as it was last night.
It’s a bad time of year to image as astronomical dark is very short (around 3.5 hrs now), but you can’t turn down the opportunity for a moonless clear night! With 1hr per RGB filter and 30min of Ha squeezed in the result is a detailed but noisy image.
This is NGC 4725 and cohorts. It looks NGC 4725 had a tangle with 4747 and neither came off well.
Imaged from the 22nd to 25th March, total integration time was 9 hours and 15 minutes, (2h20 Blue, 2hr53 Green, 2hr05 Red, 1h56 Ha). Imaged with my ASI1600mm pro, ZWO filters and trusty Orion Optics UK 250mm Newt on my CEM70G. Captured with N.I.N.A, processed in PixInsight and tweaked in Paint Shop pro.
That was a remarkable few days of good weather with DEC guiding often running as low as 0.23 rms and even RA sub 0.4 for much of the time. I’d like to think much of that performance was down to my re-jigging the balance and fine tuning the meshing of the worm gears – I had had trouble getting below 1 arc-seconds rms for the last 2 years. I know others also reported good guiding in many parts of the UK on the same days so its probably just freaky weather. Time will tell.
IC410 is a dusty star forming region about 12,000 light years away.
I’ve finally grabbed enough O3 to attempt an HOO combination. This time of year, the nebula stays above the neighbours’ trees for about 2 hrs after dark. I doubt I’ll be collecting more on this one until next year.
This image is the result of 9hrs Ha, 7hrs O3 and 45 mins RGB for the stars. By far the best stars were the Ha ones – that data was collected earlier in the year when the target was higher. I used Ha stars as a mask which tightened them a lot.
The initial HOO mix was Ha, O3, O3*.85+Ha*.15. I had to apply TGV noise reduction on chrominance because the O3 was still pretty noisy. I’m quite happy with the overall results for the amount of data.
The mono-colour Ha image reveals a lot of structure too and is overall a bit sharper.
On one of three clear nights in February, I managed to capture this amazing image:
Just three hours of RGB data has captured a host of bright and many faint galaxies. Some of the faintest detected are very red indicating a huge distance away from us. PGC2299122 and PGC2299019 are estimated to be 3.8 Billion light years away!
Making the most of my improved guiding I have been using the big 250mm Newt to image some classic galaxies:
This is a combination of several partial sessions that I had to stop for one reason or another. 10hrs split as 4hrs of Red, 2 hrs of Green and Ha, and only 1hr of Blue! I’ve no idea how many frames were rejected – I left that to the WBB scripts.
I’d like to make the Holmberg IX dwarf galaxy a bit more prominent if I can (I have some Ha there but it’s very faint).
RBG 30s sub @ 0 Gain
For once my guiding was sub 0.5 arc-sec and conditions were great all night (even with gusts of wind) so I was able to capture all the data in one session🥳. This is 3hrs or RGB and 4hrs of Ha. On this occasion I used unity gain for RGB and 200 for Ha, I’ve decided that with so few good nights it makes sense and the noise isn’t excessive. I combined the Red channel as 80%Ha+20% Red to emphasize the disruption. This is probably my best galaxy to date. Only my processing skills limit what my kit can produce.
In comparison here is a wide field image I took last year using my 150mm newt. There’s a lot wrong with the image but it shows the progress I am making.
Broadband imaging is already tricky in the suburbs but I perhaps didn’t help myself by trying to image this lovely galaxy with an almost full moon chasing it across the sky and haze. But still, for 4 hrs of data this RGBHa image is okay. The star field is aggressively clipped to remove the psychedelic rainbow mottling which I think is just pure moonlight.
For the rest of January, I had two more nights where I attempted to capture this target, luckily no moon glow just LP. So here is take 2, this time about 1 hr each of RGB and only 40mins of Ha. But you can easily see the improvement from by the better seeing and lack of moon – more fine details in the galaxy and lots of smaller galaxies sprinkled throughout the image.
Captured while waiting for M1 to clear some trees. This is an ideal target for a quick imaging session. 1.5hrs of RGB imaged with the ASI1600 on my 250mm Newtonian. Simple stacking a processing in Pixinsight. On this occasion I used a combined dark-flat with the flat frames This seems to work well.
I first imaged this supernova remnant back in 2005 using a modified web-cam.
I tried again is 2012 with a DSLR:
I was very pleased with the results then but my recent efforts (Dec 2021) are significantly better as they should be given all the high-tech I have thrown at it:
It still needs more signal to get a decent SNR but the results so far are excellent given this is 1.5hrs RGB, 1hr for Ha and S2 and 2hrs for O3. By coincidence we have the same orientation for each image so a direct comparison is easy.
1 month later (6th Jan. 2022) with an additional 4.5 NB data and 45 minutes of RGB I was able to produce this version which uses only SHO data for the Crab nebula itself:
The narrowband light emitted by the nebula images very differently showing that the Crab has lots of very complex structure: