lukebl

Thanks, David, but the roofing felt itself doesn't leak. It's the joins, due to the fiddly roof design. So pond liner would have the same problem. It seems to be dry-ish inside now, though. Most of the rain now comes in through the door, when it's windy!

Further to my recent efforts to image Venus with a UV filter, I decided to splash out and get a ZWO ASI 290MM Mini. With its super-sensitive sensor and high frame-rate I thought it was better suited to the UV filter, and so it has proved to be. I think I was lucky to get hold of this camera. With China shutting down at the moment with THE BUG, supplies of ZWO cameras and similar items seem to have run out here in the UK. As I lamented previously, my other cameras could only manage exposures of around 1/4 second (250ms) with this filter. Not sufficient to capture the seeing. However, this time I managed exposures of 15ms. I'm now awaiting the delivery of an IR filter, so that I can prepare some false-colour images of the clouds. Looking forward to some calmer, clear weather. Baader U-filter, 3x Televue Barlow, Omegon RC8 (effective focal length 4800) and a ZWO ASI 290MM Mini Mono camera. 7000 frames stacked in Registax.

I just had a go with neither CS mount in place, and I still require lengthy exposures. I guess, then, that it must be down to the UV sensitivity of the sensor.

That's very interesting. I wonder if I've just been blocking all of the UV light by having the UV blocking filter in place. There are two seemingly identical CS-mounts in the box, which have no identification marks on either, apart from the letters 'CS'. However, one of them has a pink bloom at certain light angles as you can see below, so I assume that's the UV-IR blocking one. I have been using the other one, which I therefore assume is the clear one and thus not the cause of the problem?

Impressive sketches! I didn't realise that it was possible to see such detail.

Following on from my Venus image on the 5th February, Here is another one from 8th Feb. Note the interesting bright patch on the limb near the equator. Baader U-filter, 3x Televue Barlow, Omegon RC8 (effective focal length 4800) and an Altair GPCAMv2 130 Mono camera. 3000 frames stacked in Registax. Unfortunately, as I explained in the other post, the images are very soft due to the long exposures required with my camera and this filter (1/4 second). However, it's pleasing that real features are still discernible. The clouds rotate around the planet every 4 days, even though the planet itself rotates once every 243 days.

Thanks Pete. It's a complete mystery to me how you can capture it at 14ms and I can only manage 250. I'd welcome any suggestions! I didn't think my camera was that unsuitable for the job. I note that you use Firecapture. Perhaps you can crank up the gain better in Fircapture than Sharpcap? Perhaps the filters are different?

Pete, what exposure times are you managing with Venus and the Baader filter? As I've mentioned in my post here, this filter lets through so little light that I can't capture anything with an exposure faster than 1/4 second. So I can't manage to freeze the seeing. I managed a reasonable effort with that image last night, but this evening I couldn't capture it anywhere near as sharp. I noticed someone on Cloudy Nights had managed to capture it at 1/100 sec. I wonder what I'm doing wrong?

Thanks for the comments. Yes, gain was cranked up to maximum, using Sharpcap. The sky was a bit hazy, so I could probably get faster exposures with a clearer sky.

I managed to capture some interesting detail on Venus this afternoon. This was captured with a Baader U-filter, 3x Televue Barlow, Omegon RC8 (effective focal length 4800) and an Altair GPCAMv2 130 Mono camera. 2500 frames The trouble with this filter is that it allows so little light through that the exposures were 250ms, so it's impossible to properly catch the seeing. Does anyone else manage faster exposures with this filter? Quite pleased with the result, though.

As many have noticed, Crater Copernicus was looking magnificent last night. The mightiest of the craters when the lighting is right, in my view, and rightfully named 'the Monarch of the Moon' by 19th century lunar cartographer Thomas Gwyn Elger . I don't normally image the moon, but I though I'd give it a go. These were captured with an Altair GPCCAMv2 130 mono camera, 1000 frames @ c 14ms exposures, 3x Televue Barlow, Omegon RC8 (effective focal length 4800mm). Stacked in Registax (still using V5!) Mosaic of 4 captures: I rashly thought I'd add a TAL 2x barlow to the mix, giving me a focal length of 9600mm. Focussing was difficult, but it did possibly show a little more detail? Maybe. Maybe not.

Thanks Dave!. More software to learn. Sigh!

Nice work! What software are you using to determine the magnitude? Last time we communicated you were using Muniwin.

Hi folks, Here's a capture of the International Space Station as it flew over this evening from about 17:30 to 17:32. Captured with a Canon 6d, Omegon RC8 (1600mm f/8), 1/800 second exposures, ISO800. I hand-tracked the scope through the finder as the station passed over, and fired the shutter continuously and selected the best frames. At its closest it was about 528 kilometres from me. I love the way the orientation changes as it goes over. Here's an animation of 16 frames: Here's a single frame. Shows how tiny it was!

There's a launch of another 60 of them today at 1449UT. It's scary that it's so unregulated, and that anyone can put any old junk up there and bombard us with whatever commercial rubbish they wish. Especially when other organisations are looking at ways of cleaning up old space hardware up there. It's wanton greed and pollution, pure and simple.

Nice captures. I have one of those Venus UV filters which I'm looking forward to trying out over the next few months. BTW, although Venus rotates once every 243 days, the clouds circle the planet every 4 days so you can see changes over a relatively short period.

I captured this interesting asteroid over the weekend. It's an earth-crossing Apollo asteroid on a close approach at the moment, and consequently moving by rather fast. It's currently at a distance of less than 0.1AU and won't be this close or bright again for a few decades. It spends most of its time below 21st magnitude, but it's currently around magnitude 15 and when I captured these images is was moving at a rate of 11.50"/minute. I understand that its diameter is several hundred metres. I captured a number of 30 second exposures, with my 200mm f/5 Newtonian + 0.9x coma corrector and Atik 428ex, binned 2x. The field of view is 33.5 x 25.2 arc mins. This shows the position of the asteroid at approximately 5 minute intervals. Even with 30-second exposures the movement was noticeable. This shows a series of 29 consecutive images, stacked on the asteroid using Astrometrica. This is an animation of an enlarged part of the above image. And this is a 3d image of the orbit of the asteroid. As you see, it comes alarmingly close! Running the frames through Astrometrica revealed a few other asteroids in the frame. Most were too faint for me to capture, but this one, Asteroid (37291) 2001 AP26, was at magnitude 19 and just visible in this aligned stack of 100 frames. Unlike 437316, it's in the main outer asteroid belt and approximately 10.5 km across. The streak across the middle is the path of 437316.

Here's a capture this evening of the Eskimo planetary nebula in Gemini (NGC 2392, Caldwell 39). It's easy to see and find, being bright at magnitude 10, but rather small and difficult to capture the very odd fine details. It's also in a very sparse star field, so there's not much else to see here! Omegon RC8 (1600mm FL), Atik 428ex, 15 x 180s exposures each of Ha and Oiii. Synthetic green. Field of view: 14 x 18.6 arc mins.

Small point of interest. You can make out the Crab pulsar in my image. One of very few pulsars to be visible optically. It's just 20 kilometres in diameter (20 kilometres!) and rotates 30 times a second.

Here's a slightly less 'cooked' version, which I feel is more pleasing.

Every year I'm drawn to the Crab Nebula, in the vain hope that I might be able to improve on my previous images. This is my latest attempt, using an Omegon RC8 and Atik 428ex. I foolishly thought that getting a longer focal length would mean bigger image on the sensor and thus more detail (my previous captures used a 250mm f/4.8 Newt). Of course, I'd failed to take into account pixel scale, seeing and the vagaries of the NEQ6 mount. The current combo unbinned gives a pixel scale of about 0.5"/pixel which is way oversampled. And the mount is hardly high-precision. The result is that unbinned images are no sharper than those binned at 2x. Of course, though, binning has the benefit of greater sensitivity. In fact, this image shows less detail than my previous efforts with the Newtonian. It's still a magical object, though. Anyway here it is. 20 x 300s exposures each of O-iii and Ha. Green channel synthesised with Noel's Actions in PS.

I couldn't help noticing that a few asteroids named after actors, characters or producers from the original Star Trek series are well placed in the evening sky at the moment. So I thought I'd try and capture them this week. The presence of high clouds and the nearby moon means that these are hardly pretty images, although at least they show the target in question! These were all captured with my Atik 428ex and 200mm f/5 Newtonian. The positions were all verified by Astrometrica. First up is 7307 Takei, named after the wonderful George Takei, AKA Mr. Sulu. Still alive and kicking. This one is relatively bright at magnitude 16.8, and currently very near the Pleidaes. This is a stack of 5 x 120 second exposures. Here's an animation of the first and last images, showing the slight movement over the period of about 10 minutes. Next one is 68410 Nichols, named after the equally wonderful Nichelle Nichols, AKA Lt. Uhura. Also still with us. This one is very dim at mag 19.3 and only just visible in this stack of 27 x 60 second exposures binned 2x. Currently quite near Takei in Aries. This one is 2309 Mr. Spock, a 16.3 magnitude asteroid in Cetus. 20 x 60 second exposures. The story goes that the asteroid was named after the discoverer's cat, Mr. Spock. But since the cat was named after the original Mr. Spock, then I will assume that the asteroid was too! I did try and capture 4864 Nimoy, named after Leonard Nimoy AKA Mr. Spock and currently in Aquarius, but it was close to the moon and at 18th mag. was washed out. This one is 4659 Roddenberry, named after the creator of it all Gene Roddenberry. Magnitude 18 in Pisces. 20 x 60 second exposures binned 2x, and stacked on the asteroid hence the star trails. There is also an asteroid Shatner, currently in Gemini. Sadly, none of the other original stars have asteroids named after them. There's also one named Tenagra after a place in one of my favourite Next Generation episodes: 'Darmok'. OK. That's enough nerdy stuff for the time being.

The return of Doctor Who reminded me that I really must fix the leaky roof on my Tardis Observatory. Here I am painting gloopy bitumen paint all over it today. The roof really needs a redesign to direct the rain outwards as it's getting alarmingly damp inside.

I know this is a response to an oldish post, but it's an important one. Definitely YES, geostationary satellites can be imaged, and frequently, although stacking software can usually remove the trailing. And just because they are geostationary doesn't mean that they don't move against the backdrop of the night sky. They still create trails on images. Most of them orbit in a line above the earth's equator, and thus from the UK are seen a few degrees below the celestial equator due to parallax. This means that they frequently photobomb images in that area, such as the Horsehead and the Orion Nebula. Admittedly, they are fairly faint, and nothing on the scale of Starlink which will occupy every part of the sky from North Pole to South Pole.

Is that good or bad?