geoflewis

Simply gorgeous

Very nice, with the bulge of Olympus Mons well seen at the limb. I agree that the extra FL just works, regardless what the maths says is correct sampling.

I find that the dispersion on Saturn’s rings is quite marked visually when Saturn is low elevation and observed at high magnification, which I can get with the C14, so much so that I see 3 sets of rings, red, blue and a blurred colour image in between. The ADC fixes that very well.

I do use my ADC for visual and find it very helpful, particularly on Saturn with it at such a low elevation from the UK recently.

There’s been a long discussion on optimum FL for planetary imaging on another SGL thread. The maths does indicate that x4-x5 pixel size is the optimal FR (focal ratio), which was my rule of thumb with older cameras with larger pixels, BUT even with the small pixels of modern cameras, many of the worlds leading planetary imagers still operate at longer FL, so at FR much more than x5 px size. For my recent session with Mars on 2 Dec, I started without any barlow, so with just the amplification from using the ADC, taking my C14’s native F11 to F13 (FL=4500mm). However, with the good seeing that night I popped the Baader barlow lens in, giving me F21 (FL=7650mm) and the resulting image on screen was much easier to focus and final image superior. At F21 with camera pixel size =2.9mn (ASI462MC), that’s a FR more than x7….!! Seeing is everything for planetary imaging and there’s no way that I could operate at x7 in poor seeing, so 2 Dec was the first time this year that it’s worked for me, but when the seeing is good I’d say you can push the amplification despite what the maths shows.

I think I need to take a look at Astro Surface…..🤔

Really excellent image Graham

Thanks Stuart, I finally had some decent seeing to work with.

Thanks, yes, the 3D works quite well with stereo images that are close in elapsed time.

Thanks Jeremy

Thanks Kostas, yes, I think the bigger image size at F21 helps with the edge rind a lot. I captured some data at F13 before adding the barlow and the edge rind is much worse, as are the images overall, so yet more to the optimal sampling discussion. So far so good as far as Covid is concerned, so hopefully we have got away with it, but it's still early days.....🤞

Thanks Luke. The effect of Mars rotation is much less significant than for Jupiter, but it is noticible over anything more than a few minutes and each of those 3 images has ~20 mins elapsed time, so would definitely smear without de-rotation. See my previous post with the annotated images for more information.

Here's an annotated version of the 3 Mars images. Also if you want to have a try at seeing Mars in 3D just use either of the left 2 or right 2 images as stereo images and try to bring them together with your eyes. I use my hands to block the image, so that I look at the left hand one with my right eye and right hand one with the left eye.

Thanks Neil, I was still at 5ms (200fps) - I totally forgot to change that, but with the better seeing, I think it was ok.

Well after a couple of weeks of nothing much I had an unexpected and extremely fortuitous session with Mars last night. My wife and I were due to be celebrating our daughter's birthday with her family yesterday, but in the morning her husband tested +ve for Covid, so we came home. Then around 10pm I looked outside to see that the earlier fog was clearing, so I opened up the observatory and pointed the rig at Mars. I probably had the best seeing this apparition, so ran several SER videos, including adding the Baader barlow for amplification, allow the rig to operate at ~F21. The seeing was mostly stable, but was still a bit in/out, plus fog was patchy affecting the brighness of capture, eventually shutting me down. Anyway, here are 3 images, each comprising the best 30% of 3x6 min SERs. De-rotation was just the stack from each SER, not the SER itself. Mars is now 100% phase being less than 1 week prior to it's opposition. It's good to see a bit more surface detail finally coming through. Mare Cimmerium, with finger of Sinus Gomer pointing towards the bright region of Elysium, is rotating away from the Central Meridian. The polar hood has shrunk a lot since I last imaged Mars.

Excellent, especially with the C11

I hope it's my imagination......🤣

Thanks Kostas, more fog here tonight currently, so no chance to image unless a miracle happens and it clears. I fear my throat feels a little tight, but I may be imagining it......🙄😱🤔

Lovely images Kostas. My wife and were visiting my daughter in Berkshire yesterday for her birthday today and of course there was a clear sky with Moon, Juiter and Mars all shining brightly. We were due to be there for 3 nights, returning on Saturday, with a birthday dinner planned for tonight, but this morning her husband tested +ve for Covid, so we've had to come home. I'm now hoping that we haven't caught it, as the last thing I need now, with opposition less than 1 week away, is to be ill in bed.....🤞

Superb 👏

Nice capture Stuart.

Excellent

Nicely done

Lucky you both, I'm fogged in here.....🌫️

Those are very good Mars images Kostas. Glad to see someone is getting a look, as I’ve had no chance for several days now and it’s not looking likely for some days to come