Fegato

I have the 294MC and it's a good camera, but as above, it's not consistent at very short exposures and therefore flats need to be calibrated with flat darks (rather than bias) which can be a bit of a pain. It also has amp glow and definitely requires darks as a result. The 533 has a slightly more modern sensor and like the other newer ZWOs - no amp glow, and generally better performance (lower read noise etc.). Having said that - you can take brilliant images with the 294 and awful ones with the 533 of course, so I wouldn't argue against a 294 if the sensor size suits you better.

Nice! West Wales has been the same weatherwise. Scope was out for 5 nights this weekend with a promise of multiple clear nights. All I managed was to polar align, and then the cover stayed on the whole time. Depressing…

Adding any glass into the light path will increase the required backfocus distance by an amount equal to ⅓ of the glass thickness. So e.g. if your optimum distance is 55mm, adding a 3mm filter into the light path will increase this to 55.1 mm. This is obviously a small amount, and whether there's any real impact will depend on your set up. With my RASA at F/2.2 even swapping a 3mm filter for a 2mm one has a noticeable affect on my corner stars (after re-focusing). As a result I use a clear glass filter when shooting broadband, and this has same glass thickness as my dual narrowband filter.

If the trailing is due to optical issues (tilt, backspace etc.), then shorter exposures won't help. I should have added that my shorter exposures were taken after I'd sorted out the tilt / backspace issue, and they could be short because I was only interested in the stars. If anything, I find shorter exposures with my RASA actually accentuate these sort of issues, as longer exposures can cause a bit of bloating! With regard to the L-eNhance - what are you using when you're not using it? Just wondering if the addition of the filter is changing your backfocus distance (e.g. if you had no filter at all when not using it), which could be why things are worse with it.

Wow, that's a lot of kit going at once - good luck! I will probably just stick to one rig - I have to wheel out and polar align / calibrate each time, as no observatory (although if there's a spell of clear nights I'll leave it out under cover), and I'm not overly motivated to get another one going. My solution to getting the most out of limited clear sky time is using a RASA11. I sometimes think about getting a very wide field rig with a 135mm lens and a small tracker mount, but haven't even started window shopping for that. I'm still mastering what I've got, I guess. The other thing I occasionally mull over is having a remote set up in one of the Spanish sites, maybe FL around 1200mm for smaller FOV at a higher focal ratio - but that is a lot of commitment in time and money.

Yes I suffered with this recently and it's a right pain. Not much use to you I think, but I use Pixinsight, and I found that BlurXTerminator did help a bit with the star shapes. However, in the end, I just reshot the stars quickly. This involved 10s exposures with no guiding or dithering, and only 40-50 exposures, so I didn't waste much extra time (albeit I had to wait a full month to get another clear night!). Took the stars out of the original images and patched the new ones back in.

I've got some clear nights forecast here too - I'm trying not to get too excited...

Thanks @CloudMagnet and @Mr Spock for your comments. I've been back through my processing, which has reminded me of the fact that you really shouldn't apply processes without understanding or thinking exactly what you're doing! I use Pixinsight, and it is very rich in capabilities and as a result quite complicated. I like this, but sometimes need to take more care! 1. I was applying Background Neutralisation in a sub-optimal way, failing to use a proper background sample. I'd always done this properly until I started using Photometric and and now Spectrophotometric Colour Calibration processes. In redoing this, I found I'd actually neutralised a fair bit of faint nebula, as well as failing to get a good neutralised background. 2. Some of my stretches seemed to be affecting the background. The Script EZ Soft Stretch was a particular problem, and as this is no longer properly supported, I think I'll stop using it. 3. I still seemed to pick up some loss of a neutral background through stretching. Background Neutralisation is supposed to be run on the linear image, but I tried applying it on the non-linear image and this has done the trick. It also altered the colours across the image, but as they are sort of made up anyway... Any expertise anyone can offer on maintaining a neutral background during Pixinisight post-processing would be welcome! Here's the end result anyway. Not as pink, but a lot more faint nebulosity across the image.

No that's fine - I'll have a more considered look. I guess my PixelMath attack on the red has probably done more than I wanted it to!

I've had another look this morning, and I'd obviously undone my SCNR at some point and not re-instated, so definitely some green. This might be a bit better?...

Thanks! I did SCNR some green out fairly late in the processing, but it was fairly light touch, so maybe not enough - I'll take another look when I can get some better light conditions tomorrow.

Well, the weather here in South West Wales since the end of June has been appalling, and after a pretty good first 6 months of the year, I've struggled to get much imaging done. I normally just focus on broadband and moonless nights, but with a couple of vaguely clear moon-filled nights in September, I got the NBZ filter out and had a go with that. I'm not so keen on very red Ha filled images, so the Sadr region was a bit of a challenge to process. In the end I decided to add some Hb to my Ha dominated image... or at least, I did some sort of unscientific / random "Hb" addition. This pinkish image has 15% of Red (above Median value) added to the Blue channel. If not scientific, it was relatively easy to achieve. RASA 11 on CEM120, ASI2400MC Pro. 7 hours of 120s exposures across 2 panels with IDAS NBZ filter. 100 x 10s across 2 panels for RGB stars.

Strange to call that a quad filter, as that bandpass is more like a LP filter than quad narrowband. It doesn’t seem that different to the L-Pro. Do you know how they are marketing it?

I had hope of 2-3 hours clear, wheeled it all out, and my only success was to polar align, which took ages. Clouds had come in, and I was too tired to wait any longer. Woke up in the early hours to a very bright moon shining through the window (a time when the forecast said any clear spells would be long gone). I await Saturday's forecast clear night with low expectations...

I'm half way through my version of this. Really struggled this summer with poor weather, and West Wales has not benefited from the recent few clear nights, so it remains unfinished although I started weeks ago... fingers crossed for October. Anyway, it's hard to get much definition to the Ha without using a filter. And you really need a filterless version to get the best of the dust. So a combined Ha & RGB gets the most out of this target I think. I use OSC and am using a dual narrowband to get the Ha. I don't think there's much OIII to be had here, so I'm not sure there really are any blue bits to speak of?

Just a tip on using DBE in PI... I use StarXTerminator, and if you remove the stars prior to DBE (with unscreened option not ticked) it becomes so much easier. You can clearly see what's gradient and what's dust with no stars, particularly in a rich star field like this. Perform DBE with the normalize option ticked, and then add the stars back (simple $T+stars). I now do this on every image, and it's improved my results no end. I've realised some previous images had swathes of dust and nebulosity destroyed by poor sample positions in DBE.

I can't really give any tips, as I've never really happy with sharpening on DSOs. I've used UnsharpMask on the moon and planets, but rarely on a DSO image. I guess I'm mostly shooting fairly wide field, and prefer the "nebulous" look to risking production of artifacts and yo-yo-ing between sharpening and noise reduction. I do sometimes see an image that looks sharp and good with it, and think wow - wonder how they did that!

Nice shot! I use PI, and used to do this at times, even finding that the basic Apple Photos could quickly sort out e.g. my final contrast needs. I also tried fiddling around in Photoshop, but I'm not a PS user, and generally hate it, so quickly gave up on that. But anyway, over time I have persevered in working out the nuances of the PI tools, and now find I can do what I need to completely within the one tool.

I've had lots of issues with USB in the past, and as a result have read up a lot about it (I wheel my rig outside onto a patio, and run power and connections from inside). One thing that does sadly seem to be the case, is that what works for one person doesn't always seem to work for another. As a former IT person, I hesitate to use the word random, but it feels like it sometimes! My advice based on my experience as far as it goes is: 1. Unless you really need USB3 (you might need it for planetary, but not DSO work), use USB2. So actually, using your USB2 cable is the right way to go for guided DSO work. USB3 consumes more and is less reliable when under load, particularly over longer cables shared with other connections. 2. Put powered hubs at both ends if using a long cable. 3. Use good quality cables. Most of my shorted ones are Lindy cables, so not expensive. I can't really recommend a longer cable as I had mixed experiences with them. I had tried 10m, but cut down to 5m. I had no consistent joy with long active cables, but some do. 4. Don't use the ZWO proprietary flat cables. I had regular problems with these, and found many others did too. 5. Maybe not possible for you, but if you can avoid long USB runs altogether, that would be my top recommendation. In the end, I bought a mini PC to sit with my rig (I have it underneath on the tripod tray, not mounted on the scope), allowing me short USB runs. I then connect the mount and the PC with separate 10m Ethernet cables, and run the whole thing from inside with my laptop using Microsoft Remote Desktop (this allows me to use my Macbook too, which is nice). Anyway, best of luck!

thanks Dave... but no, it's not the bottom middle, it's the bottom left. I suppose it's testament to NoiseXTerminator (or perhaps I overdid it!)... you could easily tell prior to processing, the background was much noisier in that panel.

Thanks - yes, it was around 45 minutes each for 5 of the panels and 20 minutes for the sixth. I guess it's not an exact science but at F/2.2 that 45 minutes is equivalent to nearly 4 hours at F/5 or 7.5 hours at F/7. Another key point that I always forget to mention is that I have Bortle 3 skies, which obviously helps rather a lot too!

thanks Martin - and all for the positive comments!

Sorry if you've already seen it, as I've already posted this in the Deep Sky Imaging forum. I won't repeat the commentary, but this is the Veil Nebula in broadband, a six panel mosaic producing a very wide field to bring out the surrounding dusty areas. RASA 11v2 on CEM120, ZWO ASI2400MC Pro, 4h 14' across the 6 panels

thanks Chris! Ah yes, could have been CN, must admit I couldn't quite face trying to find it on there, as I don't think I commented at the time

Imaging the Veil in broadband this summer was part of a longish list, but I was spurred on by seeing another image that showed off plenty of dust beyond the Western Veil. I'm afraid I can't remember or locate that image to give credit. Anyway, as a result I went big, and this is a 6 panel mosaic. I've only managed to gather a fairly paltry amount of data, but I used the only 2 moonless nights with any clear sky here in August, and got impatient to finish it off! One panel has only 20 minutes of data - less than half the other five, and maybe not really enough for the dithering and drizzle that I applied. But I can't really spot the difference after processing - if you're better at pixel peeping than me and want to guess which panel, please do! (the mosaic is 3 across, 2 down). The brightest part of the dust to the North West is catalogued as LDN864. The strange tadpole like thing to the south of it (which I also published separately) is LDN846. A nice spiral galaxy NGC7013 sits to the East, and above it an interesting shaped little dust cloud, uncatalogued, perhaps reminiscent of the Ghost Nebula. As for the Veil, it's bright, so even in broadband it stands out well with starless processing. Perhaps unsurprisingly the Ha is stronger than the OIII though, so some of the blue filaments you would normally see are barely visible. RASA 11v2 on CEM120, ZWO ASI2400MC Pro, total across 6 panels of 508 x 30s (4h 14') imaged on nights of 16th and 24th August.