lukebl

I was up at 5 am, preparing for the occultation under clear skies. Needless to say, the clouds had rolled in by the time of the occultation.

There were one or two gaps and I did manage to retrieve a few frames shortly before immersion, and briefly during emergence. Hardly prizewinning stuff but better than nowt, I guess! The dark looming limb of the moon on the right-hand side shows the huge difference in albedo.

Omegon RC8, Tal 2x Barlow, ZWO ASI 290MM Mini Mono camera.

21 hours ago, lukebl said:

I've been watching the weather forecast closely for this event for the past few days. It's been flitting between sunny, showery and just plain cloudy.

Currently the BBC forecast looks promising, and Clear Outside predicts ... clear outside. Fingers crossed.

The forecast has now changed to cloudy!

It is amazing to live in a climate where it's still impossible to predict the weather more than two days ahead.

I've been watching the weather forecast closely for this event for the past few days. It's been flitting between sunny, showery and just plain cloudy.

Currently the BBC forecast looks promising, and Clear Outside predicts ... clear outside. Fingers crossed.

Great image. Some sort of Swift?

I tried it yesterday (1st June) and could make Venus out with my Omegon RC8, 2x Barlow and ZWO ASI 290MM, obviously relying on the GOTO to get there. I briefly looked by eye, but the background sky was painfully white with the sun's glare, and couldn't see it visually.

It was shimmering like crazy in the heat, and I just couldn't focus on it for an image. I'm amazed how anyone can get a sharp image, however awesome their optics, during the heat of the day. How do they do it?

There was a transit of the moon by the ISS here this evening, and I attempted a double capture; one wider field with the DSLR and one detailed one with my RC8 with a 2x barlow.

Unfortunately the path was a bit further south than predicted by Calsky so the detailed view was off the frame of my RC8. But I did manage to capture this wider view with the DSLR. Canon 700d + Skymax 90 (1250mm) video record.

I started that other thread due to my difficulties collimating my 200mm RC.

My problem is that I'm too hasty! Once I'd settled down, read and re-read and re-watched various instructions and videos on the matter, collimation wasn't that difficult or time-consuming using a combination of a Howie Glatter and Cheshire, and I think I've got it nearly perfect now. The scope is so robust that it seems to hold collimation very well and if it needs collimating again, I'm confident that it wouldn't take me more than 10 minutes.

So the message is, once you've learnt the slightly quirky nuances of RC collimation, it's actually quite easy and you have a very sharp scope.

Only a few more days till Inferior Conjunction. Venus's cresecent is getting bigger and thinner and starting to be lost in the shimmering haze.

Here are some recent captures. Omegon RC8, 3x Televue Barlow, ZWO ASI 290MM Mini Mono camera.

Personally, I don't believe you need anything fancy for astro-imaging, which is why last year I bought a very basic Lenovo 100e Winbook for just £129.99 new. 4GB RAM. They don't seem quite as cheap as that now, though.

I use it to run ASCOM, EQMOD, PHD2, Carte du Ciel, Sharpcap, Firecapture, Artemis and other programs with absolutely no trouble. It has USB3, so can download planetary images at high speed. It's only drawback is the small hard drive, so I have to remember to regularly transfer big files to a separate drive. It boots up very quickly too.

15 hours ago, CraigT82 said:

What time did you capture? Earlier is better when its higher up but its harder to find in the blue sky (and have to take sensible precautions regarding the sun)

I have been capturing later (18:30 BST onwards), when the sun has passed behind my roof and the scope is in shade. When it's bathed in sunlight, I've been finding that the turbulence is even worse.

I would have though that the longer tube of your Newt would make it even worse, but clearly not!

That's a phenomenal capture. I managed to capture Mercury's disc and gibbous phase for the first time ever last night, which was very satisfying, but the seeing was terrible.

Just wondering how you manage to do it! I am having to image it over my roof, so I guess it must the thermals from the tiles after a hot day which make my seeing so bad.

5 hours ago, david_taurus83 said:

BTW, what is your pixel scale at 1.6m focal length?

It's 0.58"/pixel. I know. Way oversampled!

I've had some reasonable results imaging Venus with my Omegon RC8 coupled with a 3x Televue barlow. Unfotunately, the other planets will be poorly placed for some time yet.

52 minutes ago, david_taurus83 said:

... Apart from the spike it appears to guide quite well?

No the guiding's terrible! As you see from this single 4 minute frame, the mount appears to jump periodically.

I am having trials and tribulations with my old NEQ6 as discussed in another thread, and fear I may have irreparably damaged it.

Can anyone suggest what might be happening in this PHD Guiding graph here? As you can see, there is an oscillation over a period of about 12 minutes, which increases over time to a huge spike.

3 minutes ago, alacant said:

My guess would be that you've tightened the worm mesh too much and now it's sticking, but without seeing the logs, it's only a guess. 

Not sure the scale of the graph is correct... How do the images look?

Cheers and HTH

 

Thanks. The images are terrible! 

Having thought I'd fixed everything. how wrong I was!

Guiding is terrible. Something strange going on in DEC. Any ideas? Balance seems good and I can't detect any significant backlash.

This is using an Off Axis Guider and a 1624mm Focal length.

Something which baffles me is that Starlink received 'permission' to launch all these things from the US Federal Communications Commission (FCC).

What on earth gives them the right to grant such permissions which have a global impact, what are the criteria and how accountable are they? Seems a bit like me asking my District Council for permission to search for oil in the Antarctic.

Well, I'm chuffed to bits that, after dismantling the whole mount and reassembling it, it now appears to be functioning properly again and running smoothly.

The original problem appears to have simply been a loose worm locking ring as suggested by Stuart1971 and others, exacerbated by me messing around with the grub screws and damaging some threads and generally being cack-handed. Now that I'm less intimidated by the interior mechanism of the mount, I'd be confident to undertake the Rowan mod on my other NEQ6 myself.

It does appear to have been a creeping problem which I'd failed to notice, and explains a lot of the guiding issues I'd been having. In particular, it explains a curious satellite trail on this image which I posted a while back. I think it was simply caused by the RA drive rocking back and forth, and not by an oddly tumbling satellite. It would also clearly result in a lack of sharpness in long exposure images.

This is a capture with UV filter last night. No sign of the lovely cloud features visible a few weeks ago. This is it alongside an image from four weeks ago showing how it's rapidly getting bigger.

Baader U-Venus filter, c. 20,000 frames. 3x Televue Barlow, Omegon RC8  and a ZWO ASI 290MM Mini Mono camera.

That's nice and sharp.

I too will stick it out as long as possible to get the thinnest (and biggest) crescent. I find the most difficult thing is getting the damn thing in focus.

The seeing was fabulously steady here yesterday evening at about sunset, but despite that I could only catch the barest hint of clouds through the UV filter.

Nice view though.

Captured with Baader U-Venus and IR filters, c. 70,000 frames for UV channel. 8ms exposures. Green channel made from 50% UV and 50% IR . 3x Televue Barlow, Omegon RC8  and a ZWO ASI 290MM Mini Mono camera.

Thanks for the complement Pete, but I think your captures are superb and I think you can also tease a bit more detail out of them with a bit of a play in Photoshop.

Last night I had an exceptional period of clarity and great seeing, so thought I'd capture some great detail. However, I'm processing the captures now and they seem to have almost no detail at all even though the images are sharp. I wonder if the solar lighting angle at the current phase makes the clouds less visible? The clouds were certainly clearer at half and gibbous phase, even though the disc was smaller.

No chance of any sharp captures of Venus here at the moment due to the seeing. But quite mesmerising to watch the beautiful shimmering crescent.

Here's an animation of a few 12ms frames captured this evening through the Baader UV filter.. Omegon RC8, Atik 428ex, 3x barlow.

Here's a sequence of captures of Venus over the past two months. Recently, I've been disappointed at the lack of detail compared to a month ago, possibly due to the seeing deteriorating or maybe the vagaries of my own processing techniques are to blame.

I've shown two versions here. The top one has the UV image in the red channel, and IR image in the blue channel. The bottom version is reversed. The convention seems to be for the top version, but as it's false colour anyway, I think I prefer the blue version.

Omegon RC8, Televue 3x Barlow, Atik428ex, Baader UV and IF filters.