lukebl

Hi folks,

Here's a rough animation of the shadow transit of Europa and the occultation of Ganymede from last night (23rd September 2021).

As you can see, the seeing was pretty variable, but with a few moments of pretty good seeing.

200mm f/5 Newtonian, 3x Barlow, ASI 120mc-s camera. Stacked from 25 videos of 3000 frames, captured every 4 minutes. I intended to catch an earlier part of the transit, but hadn't factored my neighbour's roof into the equation, so the earliest frames wasn't until 20:43 BST

This was the best frame out of a bad lot

Heres'a small animation of Jupiter from the evening of 21st September.

Captured in appalling seeing conditions (I don't know where you folks claiming good seeing are getting it from!) and varying transparency due to high cloud. I've kept the animation small due to the poor quality of the indiviual frames, but at least you can see a few details.

18 x 2000 frame videos captured every 5 minutes from about 20:45 BST using Firecapture. 200mm f/5 Newt, ZWO ASI120MC cam, 3x Televue Barlow. 21ms exposure, 47 fps.

I do a bit of imaging with my Coronado PST, using an ASI 290MM Mini cam (mono) and 2x Barlow. I've also had good results with a QHY5-II Mono. You should be able to get reasonable results with yours.

They key advantage of the 290MM Mini and the QHY5 is that they fit entirely in the eyepiece holder so that you can get focus, which the DSLR was never able to manage without a barlow. The DSLR was also way too big and cumbersome. I also found that imaging with a colour camera just didn't work - I found focussing the bright red image nearly impossible, and the resultant colour image was never satisfactory.

This is a quick capture from this afternoon. About 500 frames captured with Firecapture with the ASI 290MM Mini and 2x Barlow, plus a bit of colour tweaking in Photoshop. This is nearly the full frame view. You do get a bit of gradient across the field which you can get rid of with flats, but it doesn't really bother me. I think it gives a more 3d effect.

I have the 290MM Mini, and it’s an excellent and very sensitive little cam.
I’m not sure that you’d gain anything with with the 178 as you’re really just getting a bigger sensor which isn’t really necessary as one tends to crop the image using ROI anyway.

I captured this great prominence today. This is a painstaking animation of about 22 frames captured every 6 minutes or so, over a period of about 2 hours

Captured with the basic unmodded Coronado PST with a 3x barlow, ASI290 Mini cam. 2000 frames per capture at about 60 fps, processed in Registax 5 and Photoshop.

Here's a single capture. Shame about the Newton's rings, but you still get a sense of the scale of it.

57 minutes ago, osbourne one-nil said:

….My main concern is collimating an RC; it's not that hard is it?….

Hi, I read this bit and recalled my own tribulations regarding RC collimating, about which I had a few gripes on this forum. It’s a subject often discussed on the forums.

However, once you get used to the nuances of RC collimation I eventually found that it’s really very simple, and I feel a little embarrassed at my earlier thread. It also doesn’t require specific tools that some websites suggest. The great thing, though, is the the mirrors stay put and my RC8 simply doesn’t need collimating despite being taken on and off the mount and shifted around.

Nice capture. What equipment did you use?

Big solar prominences right now! Shame it's cloudy here.

Here's the latest Solar Dynamics Observatory image.

Here's an animation of Io and its shadow transit from last night. The window of opportunity for viewing Jupiter from my obs  at the moment is very narrow due to various obstructions so this was all I could manage.

This is composed of 14 x 2000-frame videos captured every 5 minutes, starting at 23:10 BST. 200mm f/5 Newt, 3x Barlow, ZWO ASI120MC.  I've kept it small, so you can't see how bad the images really are!

On this very day four years ago, my two sons and I were standing in the Wyoming prairie watching a total solar eclipse. The trip was years in the planning.

I wonder if we'll ever go anywhere again.

I've only just got round to processing these images from the night of 12/13th August.

30 second exposures captured with a Canon 700d camera 18-55mm lens @ 18mm to hopefully capture some Perseids. However, I barely captured any, and by all accounts the Perseids were a disappointment this year. However, there was an outburst of meteors a day late, as reported on Spaceweather, when there was a brief outbust of 2-300 per hour.

I decided to stack the images in hour-long batches:

After a night not seeing many Perseids, I scooted up to North Norfolk and captured this transit of the ISS with my PST Coronado. The path of visibility for this transit was only 6.5km wide.

The weather wasn't promising and at the precise moment of the transit, clouds rolled across and the image went virtually black, so I assumed that I'd missed it. However, on stretching the image, I realised that I did manage to capture the transit.
Coronado PST, ASI290MM cam, Exposure 0.88ms, 23 frames per second.

On this transit, which took just 0.66 seconds, the ISS had an angular size of about 50 Arc Seconds and was 513km distant. Other upcoming transits near me have the ISS at 1416km distant and only 20 Arc secs across

Sounds like some of you were luckier than me. I guess my eyes aren't what they were.

Here's an hour's worth of my north-facing camera. One Perseid and a brighter sporadic (or maybe a satellite flare). Canon 6D. 30 sec exposures ISO 1600.

I don’t know about you, but I was pretty underwhelmed by this year’s Perseids.

I had two clear nights and stayed up for a few hours both nights, and also had two cameras running in different directions, but saw and captured very few compared to previous years.

What are other’s thoughts?

8 minutes ago, randomic said:

During midday to midnight, the same number of meteors are hitting Earth, it's just that most of them are hitting the other side of the planet from you.

Fair enough! I think I get now. Many thanks!

1 hour ago, randomic said:

sn't it just that from midnight-midday you're on the side of the earth which is going "forward" into the meteors?

But, like I said, if the meteors are travelling at 30,000mph and the earth is rotating at 1000 mph, it wouldn’t make much difference whether the earth was rotating into the storm or away from it. i.e. the speed of the meteor entering the atmosphere would be c. 29,000mph in the evening and 31,000mph in the morning. Not much difference. 

1 minute ago, russ said:

Will you be doing another video tonight if you get the chance?

Thanks! I sure will. The forecast here is fairly promising for tonight, and there should be a lot more activity.

Here's a video of about 6½ hours of 30 second exposures from my garden, from about 22:00 BST to 04:30 BST) compressed into just over a minute. Canon 700d, 8mm Samyang fisheye lens, f/3.5, ISO 800. Night of 11th August 2021.

The aim was to capture some Perseids. There were a few relatively minor ones, plus a few planes, satellite trails and flares. Nice cloud movement, though!

8 hours ago, Tiny Clanger said:

A previous thread has some good explanations (and some confusing ones too)

Thanks. I missed that earlier thread. 

I found this quote from National Geographic: “Think of it like an automobile that has a windshield on the side facing forward,” Murphy says. “You get more bugs on the front windshield than you do on the back window.”

Like I said. I don’t buy it! The difference in relative speed of the meteor before and after midnight would be insignificant. The bugs are still flying into the back window nearly as fast as on the front windshield.

17 minutes ago, globular said:

Isn’t it just that there are more hours of darkness after midnight than before… 

Well, that what I think too. But as I said, various guides (books, internet, magazines, etc) perpetuate the claim that there are more meteors in the hours before dawn because the earth is rotating into them.

I’ve never bought that unfounded claim for the reasons I said in my post.

As I sit here waiting for some Perseids I’ve been giving some thought regarding the frequency of meteors before midnight and after midnight. i.e. the fact that meteors are apparently more frequent after midnight than before. 

The perceived wisdom is that in the morning the earth is rotating INTO the meteoroid, and thus the relative speed is greater, air friction is greater, and the meteors are brighter and otherwise faint ones are more visible. In the evening the earth is rotating AWAY from the meteoroid, so the relative speed is slower, ipso facto less air resistance, less friction and the meteors are fewer and less bright.

HOWEVER, my understanding is that meteors are travelling at, say, 30,000 mph or more, while at the equator the earth is rotating at around 1000 mph (and effectively zero at the poles). So the speed of the Earth’s rotation is pretty negligible compared to the meteor’s speed, and can’t really have a significant effect on the meteor’s entry speed? A meteor hitting the earth’s atmosphere at 31,000 mph surely can’t be significantly brighter than one hitting it at 29,000 mph?

Or am I just being stupid? 
 

Hi folks.

This is a painstaking animation from 20 videos captured every 10 minutes (about 3½ hours) with a PST Coronado this afternoon, 2x TAL Barlow, ASI290MM Mini cam. Each video was consisted of 500 frames. The prominences were 2.25ms exposures at 64 fps. The sun's surface was a single capture of 500 frames at an exposure of 0.22ms. Stacked in Registax 5, and processed in Photoshop.

Obviously, in reality the sun's surface should have been animated too, but I sadly didn't have the patience to do an additional 20 videos of the surface on top of the prominence ones. That's for another day when there's a completely clear sky, uninterrupted by passing clouds. However, I'm reasonably pleased with the result.

I'm really looking forward to a biggie, like this legendary one in 1946!

Now that the sun's livening up a bit, I did a quick capture today with the PST Coronado, 2x TAL Barlow and ASI290MM cam.

I've probably overcooked the processing a bit, but I'm always amazed at what this tiny wee scope with a mere 40mm objective can do. Obviously not a patch on bigger specialised scopes but worth every penny as a grab-and-go IMHO.

1200 frames, 0.3ms exposure, 30 fps. Stacked in Registax 5 (I'm very old-fashioned):

Prominences 620 frames, 1.8ms, 30 fps

Inverted:

Prominences combined

Here's a not-so-sharp capture of the ISS transiting the moon at sunset last night. It was hot and above the heat haze of my garage roof.

I captured it using an RC8, 2x Tal Barlow (3200mm FL), ASI290MM cam. About 29 fps. The big, middle and small craters in a line from top to bottom are Ptolemaeus, Alphonsus and Arzachel.

It's the first time I've captured a transit with the ISS illuminated. Not at its best though. Apparently, the station was 1018.95 km distant. At other times it can be half that distance

I also captured a video on my Canon 700d, with a 70-300mm Zoom. The ISS moves from bottom right to upper left, with a couple of swifts buzzing by the moment it crosses the moon. It was around mag -2.9 at the time.

I love it too. I want one!

Belgium’s finest export. As a complete Tintin nerd since infancy, I’ve always said that Hergé’s Adventures of Tintin would be my specialist subject if I ever applied to go on Mastermind. I’ve always thought it strange that in almost every language the captain is called Haddock, but in Afrikaans he’s Sardine!