tomato

Continuing my attempts to persist with DSO imaging right through the summer, here is NGC 7822, 50 x 3 mins with the SY135/IMX571c/NBZ and RASA8/QHY268c/NBZ, captured under 75% Nautical and 25% Civil darkness. Both have been processed to create a pseudo HST palette. I have tried to combine the data from both rigs to create a hybrid FOV, but this has not been a success. Thanks for looking, nights drawing in from next Tuesday...😉

Apologies, much later than promised, but here is the StarTools version.

Yep, my free trial ends in 2 days but I’ve seen enough to justify the purchase, especially as I already have StarXTerminator. I have seen some artefacts when applying to below par data but you can’t get around the ‘garbage in, garbage out’ mantra.

Yeah, our robust equatorial mount built for Astrophotography by @Tomatobro in the late 1980’s I recall had 240v synchronous motors, don’t go poking around the mount in the dark!

Wow, you have achieved another great result on a seemingly “impossible” target from your location. At this time of year I really enjoy trying to image under adverse conditions, e.g no Astro darkness, moon up, and am finding that with the right setup (RASA8, IMX571c camera), quite reasonable results can be obtained. With the equipment now available I think the time is right to review the advice about what can and can’t be attempted with respect to local sky conditions.

Unless I’m missing something, I can’t see how stacking narrow band pass filters will work. The first filter is only letting light through of a specific wavelength which the next filter will then block. However, I do agree mono is faster, but for whatever reasons based on posts on this forum, there does seem to be a lot more IMX571 colour cameras in circulation than mono versions.

On the copyright issue, I haven’t published the APOD or indeed used the dataset that was used to create it, and certainly not seeking any commercial gain from my effort. Vlaiv, you make an interesting observation, I stretched the combined channels in StarTools, APP and PI, and they all gave very different responses. The auto stretch function in StarTools gave a typical wide dynamic range result, I could not set a workable black point in APP (massive change in LH side of the histogram for a minute change in the slider, regardless of what range was set,) and I used the Histogram transformation tool in PI to produce the image I posted. On my screen the core looked blown out, so I adjusted this with the highlights tool in Affinity Photo. I’ll post the StarTools result tomorrow, I’m currently trying to image LBN 576…

I have just thought, even though the data is in the public domain, I may have infringed some NASA copy right, if so, Mods please remove.

Well, I couldn't find the dataset used in the APOD, but did find some 'matching' HaRGB files. Each channel appears to be a 6 panel mosaic and some of the joins are a bit rough. This is a quick zip through PI and AP, it has turned out a lot softer than the APOD. I found the exercise weirdly intimidating, mindful that I was processing a dataset which is literally out of this world and from a telescope that has produced dozens of iconic astro images. I won't be giving up the day job.😄

Hi Alan, For wideband imaging I swap out the NBZ for a 2" IR/UV cut filter, so the Celestron clear window is now resigned to the spares box.

Thanks guys! Being a huge galaxy imaging enthusiast this means a lot, I enjoyed this challenge immensely and learnt a bit along the way on stitching mosaics together that contain a lot of background sky. Congratulations to all the entrants, lots of cracking galaxy images in there.

A very absorbing 1 hr TV programme, just a very knowledgeable, wise and engaging gentleman talking expertly on a wide range of cosmological and philosophical topics. I never thought I would see a programme like this on today’s TV ever again.

Initially I removed the Celestron clear window and put my un-mounted NBZ dual band filter in this location,but as you say, it was a bit fiddly. I also wasn’t keen on the soft backing material attached to the supplied Celestron adapter, preferring a solid machined face contact to reduce variation on assembly. Fortunately I have access to machine tools so a hybrid QHY 268c/RASA8 adapter was made which can accommodate a screw in 2” filter. It is essentially the same set up as the Artesky unit. I have included the dimensions, but the adapter was made specifically for attaching the QHY version of the IMX571c camera.

I have now found the source of the original HST data, don’t hold your breath…

If, like me, you are a fan of galaxy imaging, please take a look at today's APOD of M51. I've seen HST images of this galaxy before, but this one is just stunning in it's detail. The trouble is, it is so good that it just makes me despair about what I can achieve with my own setup...🙄 Astronomy Picture of the Day (nasa.gov)

I suppose if the data is made available as a visual representation of light and colour then it can be manipulated by existing processing software, but I note that the test images released to date have been essentially monochrome (shades of red?).

I would have thought that given the nature of Broadband imaging in that the luminance channel is the broadest spectral range, and the most important with respect to capturing detail, it isn't necessary to pay out for the most expensive filters. There are many fine examples of broadband images captured with the colour versions of the IMX571 sensor, and they are relying on the Bayer matrix filter. For my mono setup I personally went for a set of Baader LRGB filters, but that was before ZWO began offering filters. As you point out, it is a very different story for NB imaging, so I think you have made the right choice in going for high end filters.

A well heeled few could make it happen but I think the majority of folks on SGL for example, like tinkering with stuff in their own backyard. If super quality imaging data was a big draw, pay to use telescope sites would be shooting up in Atacama and such places and although there has been growth in this area of amateur astronomy, it hasn't taken off to the extent I thought it would. A while back a spell of near constant cloud for a month did make me consider it, and if I sold all of my kit it would have funded many hours on an imaging rig in Spain, but in the end I decided I wouldn't enjoy this hobby half as much if I was just sat at a computer all the time.

Tonight I was trying to align my RASA8/QHY268 FOV with my SY135/IMX571 FOV and it would appear one is a mirror image of the other. You can see I posed the above question but am I correct in thinking that the difference is caused by one being a lens system and the other is a mirror system? I guess APP will sort them out if I want to combine the data but it is a bit unsettling trying to compare the subs on the monitors. Maybe NINA can auto flip an image before displaying it?

Thanks Luke, I can almost do the process from memory now rather than follow the video! I’m using NoiseXterminator now rather than EZ, so am applying it at the non linear stage. I find with these short integration times the green channel can be quite noisy after bringing it up to match the red, so NoiseXT does a good job at this point prior to channel combination.

Thanks for the comments, I certainly didn’t realise so much would be in the FOV, I use Stellarium to plan the images but I don’t think my version displayed the Lobster’s Claw.

This is last night's 2.8 hrs data with RASA8/QHY268c FOV centred on the Bubble Nebula, chosen as it was opposite in the sky to the 83% illuminated moon, albeit our satellite was low in the sky. Taken with the NBZ filter and processed following the @Luke Newbould tutorial to produce a pseudo HST palette. It doesn't do the Bubble justice, you have to squint to see it, but I didn't realise the FOV would capture the Lobster's Claw, so that was a bonus. Don't look at the stars too closely, especially in the bottom RH corner, the rig was dis-assembled today to put the SY135 alongside, so I wasn't going to spend an hour adjusting the tilt, and TBH imaging these kind of targets in the summer is just to keep the rig ticking over. Thanks for looking.

Here is a bit of fun. We had a nice few days last week at a hotel on the North Devon coast, Mrs Tomato pushed for a hotel break so I wouldn't try and lug an imaging rig with me like I usually do when we go to a coastal location. So instead I went super minimal, my ancient Pentax K100D DSLR, (CCD sensor, no less), 50 mm lens, dodgy webcam tripod and a intervalometer. I perched it on a wall of the terrace in front of the hotel, and took some 10 sec snaps even though the moon was up, a stiff breeze was blowing and plenty of wispy high cloud was evident. Part way through an enthusiastic and slightly inebriated fellow guest came along and asked me what I was doing and promptly picked up the camera! I guess he wouldn't have done that if I had the full rig set up, but he was only showing an interest. My AA batteries gave up after 30 attempts at holding the shutter open, so I packed up and went to bed. This is the best of the bunch, 7 x 10 secs of the Cygnus region. I plate solved the image using Astrometry.net but I don't believe any of the 'nebulosity' is genuine, it's more likely an artefact of processing the high cloud.😉 Annotated

According to the article on BBC News, it has already been hit 5 times, this latest impact being the most significant. If it keeps this hit rate up it will look like a “Welcome to Texas” sign in no time…

Maybe you can successfully install the latest version of Starnet for PI, but if you are getting on well with StarXterminator for PS then it’s largely academic.