michael.h.f.wilkinson

Nice work. I have the feeling the focus might be ever so slightly off, but there is plenty of detail to be seen

That looks very nice indeed, especially for a single shot. The only way to improve it any further is by stacking multiple images using AS!3, after which you can sharpen a bit more

No problem whatsoever. I have run an ASI183MC (20 Mpixel or so, only used at full resolution for lunar and DSO) on various laptops with no issues, and none had that kind of screen resolution. The main issue is having a fast SDD to keep up with the data rate. Even on a fairly old Core-i3 laptop using an external (USB3) Samsung T5 SDD, I got good data rates.

Incidentally, this was the first time i made my flats with the flat panel that arrived on Saturday. It reeally makes creating flats so terribly easy. Great tool

Really nice result

Really nice result!

Despite the moonlight, I decided to have a go at some DSO imaging, using narrow-band to battle the moonlight. I used my Meade SN6 6" F/5 Schmidt-Newton with ASI183MC camera and Optolong L-eNhance filter on my Great Polaris mount. I first grabbed about 1.5 hours on the Crescent Nebula, which I added to an earlier batch of data for a total of 5 h 18 min exposure. Quite pleased how this came out. As the Crescent moved towards the neighbours roof, I switched to the Crab Nebula, gathering just over two hours of data. By itself, I was quite impressed how much detail APP managed to get out of these data, as the moon was really rather too close for comfort. I also combined it with earlier data, for a total of 3 h 17.5 min of exposure Hopefully I can add more, and better data over the winter.

That's just the smartphone camera shaking too much, I would say

Your graph shows only the 5x isn't a tele-centric, the others are good approximations.

Never had an issue on the moon with either the Meade TeleXtenders (2x and 3x) or the 2.5x PowerMate in any of my scopes (Celestron C8, Meade SN6 Schmidt-Newton, and APM 80 mm F/6 triplet). As I understand it, removing the second lens group turns your tele-centric lens into a Barlow, which rather defeats the point of having them.

My first telescope was a DIY Dobson-like 6" F/8 Newtonian

I am going for the Crescent with an Optolong L-eNhance filter. Subs don't look too bad. Might try the Crab when the Crescent is too low, but the Crab might be too close to the moon.

At it again with the Meade SN6 Schmidt-Newton

Sounds like some internal reflection of flat optical surfaces in the optical train. I do remember having some internal reflection issues in my Coronado scope, but not in my earlier Lunt LS35THa

Finally got a chance to trot out the full solar kit for a longer session, across the road from where I live, so battling dying laptop batteries and the like. I set up the Vixen Great Polaris mount, and attached the APM 80mm F/6 triplet, with a Beloptik Tri-Band ERF in front. First, I grabbed some WL data with my Lunt wedge and Baader Solar Continuum filter, using the ASI178MM. A stack of 500 out of 2000 frames gave me this: Using a 2.5x PowerMate I got this detail shot, not brilliant as seeing wasn't great I then swithced to the Lunt B1800S Ca-K module, and got a decent disk Grey scale: Pseudo colour: Part inverted: Part inverted + pseudo colour: Some big prom activity to be spotted in the part inverted shots. Had I known when I shot the H-alpha, I would have prioritised those areas. As it was, the H-alpha part had to be cut short, due to the aforementioned battery problem. I did get a couple of good shots with teh Solar Spectrum 0.3 Å H-alpha filter used with a Baader TZ-4 4x tele-centric lens and ASI714MM (which can only capture small portions of the sun. I got a mosaic of the area around the big AR: To my surprise, the current version of MS-ICE does seem to work on H-alpha data. It really struggled in the past. I found a few other useful bits in the data intended for a full disk mosaic, which alas must be left unfinished: I really need to get a 12V power supply for my laptop to prevent this from happening again. Still, it felt good to image the sun in H-alpha for the first time in ages

This arrived today: a Gerd Neuman Aurora flat panel suitable for both the Celestron C8 and the Meade 6" Schmidt-Newton, and a 2" TS Concenter Collimation eyepiece for my Schmidt-Newton

Gravitational lensing by things not seen by our telescopes is almost the very definition of dark matter, apart from other gravitational effects like the motions observed in the outer parts of galaxies in H-I observations by Westerbork and other radio telescopes. Asteroids do not explain the effects seen. The idea that the algorithms used in computation are wrong can be countered by the fact that many different pieces of code have been developed by different groups, and the different packages yield similar results. All the code used is open source and peer reviewed, so unless you can point to a particular error you have found (always possible), just saying the code must be wrong is not a good scientific argument.

Very nice. Cloudy here at the moment, alas

Looks like a fairly slow 70-80 mm refractor of some kind (achromat, most likely), on something very like a sturdier EQ2 mount (and nice wooden tripod), which looks a bit like certain Tasco mounts. Any information on the silver-edged black plaque on the focuser? I would almost guess this is more like 1970s or 1980s vintage. I doubt it is worth shipping over

Very nice indeed

I won these in a raffle at SolarChat

Just had an early tea break to have a look at the sun, both with the Lunt 8x32 SUNoculars, and the Coronado SolarMax-II 60 in single stack mode. Even the little Lunt picked up three big sunspots on the southern hemisphere. The most eastward one clearly the biggest. The H-alpha scope revealed far more detail, with swirling plage and filaments east of the big spot in particular, but smaller patches of plage trailing the other sunspots too. In the northern hemisphere, one or two bright swirls could be seen. A small prominence was visible near the big spot, and another more northwards. Lovely to see the sun coming back into a more active phase

Just had second light with the Explore Scientific 12 mm 92° eyepiece, this time in the Celestron C8. The moon and Mars were the targets, both in a hazy sky, but beggars can't be choosers. At around 170x magnification, the moon almost fit into the massive field of view. The image was really sharp across the field. Eye position is critical, but I soon got used to finding it. Mars showed some detail, and a slightly gibbous phase. The higher magnification of the Pentax XW 7mm was pushing seeing conditions too far. I switched back to the moon, and had another stare at the details. Some lovely subtle relief could be made out quite a way from the terminator. However, hazy clouds were getting thicker, so I packed the kit up.

Bit late to this discussion, but you can get the ring nebula with these ZWO colour cameras, you just need more exposure time, I used to have the ASI224MC, but haven't used it for DSO imaging. I have used the ASI178MM with filters, and the ASI183MC without, or with the Optolong L-eNhance filter, and that gives good results, but requires much longer exposures than for planets. This was taken with the Meade 6" F/5 Schmidt-Newton, using 151 15s subs, which isn't nearly enough, and the rather big FOV of the ASI183MC makes the ring seem a bit forlorn The crescent is a more sizeable target (but still needs more data) Here are a few more recent targets All taken with the same combination (and all in need of more data ).

Lovely capture. Quite a monster sunspot is turning this way!