wimvb Posted November 8, 2020 Share Posted November 8, 2020 (edited) After a few years with the small sensor ASI174MM-Cool, it was time for an upgrade. I got the new ZWO camera ASI294MM-PRO with Optolong 31 mm LRGB filters. As a test I pointed my scope at the Perseus galaxy cluster Abell 426, with its main attraction ngc 1275. This is just short of 4 hours of data. Humidity was too high to capture any luminance data. Besides, the moon, though late to rise, was still too bright for any decent luminance. I also couldn't collect any Ha, because the screws that hold the 31 mm filters in place, are in the way for my 1.25" Ha filter. I will need to get a 31 mm Ha filter to complete my set. Technical details: 30 x 150 s (each) RGB, flats and darks, taken with the ASI294MM-PRO on my SW MN190-DS. Mount: AZ-EQ6 Filters: Optolong LRGB 31 mm filter set. Captured using INDI/Ekos, guiding with the internal Ekos multi star guider. Processed in PixInsight. Atmospheric conditions were far from perfect. The relatively warm weather we've had, has caused the air to be saturated with water vapour. We've had mist forming every night and this has cut imaging sessions short. As a result, this image is a bit soft. Guiding RMS was just below 0,9", about the same as my imaging scale (0,95"/pixel). There are still plenty of things to work out with this new combination. For one, I need to move the prism of my OAG up a few millimeters, as it creates a shadow/reflection where it sits now. I also have to figure out how to activate the internal window heater in the camera, because I may have had ice build up, causing circular gradients that I couldn't remove completely. About the target: The Perseus galaxy cluster is quite fascinating. Its main member (ngc 1275, about 250 Mly distant) is a very active galaxy that is in the process of devouring another galaxy. This is just about visible in this image. The remains of the victim galaxy are just visible around the predator. Ngc 1275 has a massive black hole at its center that spews out radiation and hot gases. These gases form Ha filaments that surround the galaxy. These filaments are 200 ly in width and 20 000 ly long, and are kept in place by very strong magnetic fields. The Ha filaments are also just visible as red patches around the galaxy, in this image. So, despite various issues with this image, the full size version shows some very nice details. The whole field is filled with galaxies. PixInsight identified the larger and more prominent of these galaxies. 19 November: A reprocess, removing gradients, etc Edited November 18, 2020 by wimvb reprocess 20 Link to comment Share on other sites More sharing options...
gorann Posted November 8, 2020 Share Posted November 8, 2020 Great first light! Nice details when zoomed in as you point out. But zooming in I also noted something looking like faint halos around the brighter stars - not a major issue but I hope it is not the Optolong filters since I just bought a set. Have you aimed at any really bright stars yet? Link to comment Share on other sites More sharing options...
MartinB Posted November 8, 2020 Share Posted November 8, 2020 Cracking first light Wim? I will be looking at your images with interest since I have recently purchased the same camera. I too have a SW MN190 although for the time being I will be using my FSQ106. Interested to hear about your comments on the window heater. I had assumed that operated automatically, along with the cooling, but that it requires an external power supply, however, I may well be completely wrong about this! 1 Link to comment Share on other sites More sharing options...
wimvb Posted November 8, 2020 Author Share Posted November 8, 2020 (edited) 3 hours ago, gorann said: Great first light! Nice details when zoomed in as you point out. But zooming in I also noted something looking like faint halos around the brighter stars - not a major issue but I hope it is not the Optolong filters since I just bought a set. Have you aimed at any really bright stars yet? The haloes are processing and atmospheric condition artefacts, and not filter related. The only bright stars visible during the coming week will be on netflix and hbo. I will be clouded/fogged in for the foreseeable future. Edited November 8, 2020 by wimvb Link to comment Share on other sites More sharing options...
wimvb Posted November 8, 2020 Author Share Posted November 8, 2020 50 minutes ago, MartinB said: Cracking first light Wim? I will be looking at your images with interest since I have recently purchased the same camera. I too have a SW MN190 although for the time being I will be using my FSQ106. Interested to hear about your comments on the window heater. I had assumed that operated automatically, along with the cooling, but that it requires an external power supply, however, I may well be completely wrong about this! Thanks, Martin. I use Ekos for imaging, and I have no setting for the dew heater in my current indi driver. I may need to update the driver to have access. If ZWO have added this to their software development kit, that is. If/when ZWO have added it, it will turn up in ekos automatically. Link to comment Share on other sites More sharing options...
gorann Posted November 8, 2020 Share Posted November 8, 2020 7 hours ago, wimvb said: The haloes are processing and atmospheric condition artefacts, and not filter related. The only bright stars visible during the coming week will be on netflix and hbo. I will be clouded/fogged in for the foreseeable future. Good to hear that the filters perform! Thought it could be processing. Got nothing but grey skies in the forecast here too😣 Link to comment Share on other sites More sharing options...
kirkster501 Posted November 11, 2020 Share Posted November 11, 2020 (edited) Cracking image, I love these galaxy cluster images. Perseus A is indeed fabulous. The most massive object in the local universe. Nicely framed and great colours. Shameless plug - I did a post of three of the Abell clusters for folks that are interested in them. Hope you don't mind me adding to your post Wim. Edited November 11, 2020 by kirkster501 1 Link to comment Share on other sites More sharing options...
vineyard Posted November 11, 2020 Share Posted November 11, 2020 That looks lovely. I've not been able to set up my imaging rig for a few weeks now for logistical reasons, and am quite missing AP! Will follow this w interest as one dayyear I would like to switch to mono - for the time being v happy with my colour ASI294MC Pro, so intrigued about the mono equivalent. Curious to see how it compares to the Moravian C1+ but can't seem to find many reviews of that yet. Enjoy the netflix stars! 1 Link to comment Share on other sites More sharing options...
wimvb Posted November 11, 2020 Author Share Posted November 11, 2020 27 minutes ago, kirkster501 said: Shameless plug - I did a post of three of the Abell clusters for folks that are interested in them. Hope you don't mind me adding to your post Wim. By all means, be shameless. 😀 I don’t mind. Link to comment Share on other sites More sharing options...
wimvb Posted November 11, 2020 Author Share Posted November 11, 2020 12 minutes ago, vineyard said: Enjoy the netflix stars! Too many holiday comedies atm, I’m afraid. 14 minutes ago, vineyard said: That looks lovely. Thanks 14 minutes ago, vineyard said: I've not been able to set up my imaging rig for a few weeks now for logistical reasons, and am quite missing AP! Having a permanent setup helps a lot. 15 minutes ago, vineyard said: being v happy with my colour ASI294MC I considered that camera, but I also like mono. And as I already have a filter wheel, the choice was easy enough. 1 Link to comment Share on other sites More sharing options...
astro_john_palmer Posted November 11, 2020 Share Posted November 11, 2020 Awesome! Love these galaxy cluster images as they give such a great impression of scale. 1 1 Link to comment Share on other sites More sharing options...
kirkster501 Posted November 12, 2020 Share Posted November 12, 2020 14 hours ago, astro_john_palmer said: Awesome! Love these galaxy cluster images as they give such a great impression of scale. They're awesome aren't they? Makes us feel very small amidst such immensity. How many beings and civilisations must exist amongst that vastness (said in a Carl Sagan accent 😂) Link to comment Share on other sites More sharing options...
kirkster501 Posted November 12, 2020 Share Posted November 12, 2020 @wimvbI'm also going to have a go with my new colour camera on these at a wider imaging scale when they next come round in Spring. 1 Link to comment Share on other sites More sharing options...
wimvb Posted November 16, 2020 Author Share Posted November 16, 2020 A rework of my original image. It turned out that my flats weren't working properly, causing colour gradients which were hard to remove. I recalibrated the subs without flats and used DBE to remove most of the vignetting. This version was a bit easier to process. 2 Link to comment Share on other sites More sharing options...
MartinB Posted November 16, 2020 Share Posted November 16, 2020 What do think caused the problems with your flats Wim? Link to comment Share on other sites More sharing options...
wimvb Posted November 16, 2020 Author Share Posted November 16, 2020 25 minutes ago, MartinB said: What do think caused the problems with your flats Wim? I put the led panel directly on the scope. The secondary mirror holder caused shadows and possibly very weak reflections. Normally I put the panel on the dew shield, but for some reason not this time. Live & learn. Link to comment Share on other sites More sharing options...
MartinB Posted November 16, 2020 Share Posted November 16, 2020 1 hour ago, wimvb said: I put the led panel directly on the scope. The secondary mirror holder caused shadows and possibly very weak reflections. Normally I put the panel on the dew shield, but for some reason not this time. Live & learn. There is just no end to the things that can trip us up! 1 Link to comment Share on other sites More sharing options...
wimvb Posted November 18, 2020 Author Share Posted November 18, 2020 Some more tweaking, cleaning up residual gradients, etc. 5 Link to comment Share on other sites More sharing options...
johnrt Posted November 21, 2020 Share Posted November 21, 2020 Ahaha! More galaxies than you can throw a stick at! My kind of image 1 Link to comment Share on other sites More sharing options...
Space Oddities Posted November 26, 2020 Share Posted November 26, 2020 Superb image Wim! Have you seen that ZWO released a firmware update yesterday? This allows you to unlock binning 1x1, 47 MP resolution and 2.3µm pixels. The ASI294MM was actually "locked" in bin 2x2, to match the resolution of the ASI294MC, but in reality the sensor is a 47 MP one. That seems like a nice option for short focal lengths lenses/scopes! 1 Link to comment Share on other sites More sharing options...
wimvb Posted November 26, 2020 Author Share Posted November 26, 2020 3 hours ago, Space Oddities said: Superb image Wim! Have you seen that ZWO released a firmware update yesterday? This allows you to unlock binning 1x1, 47 MP resolution and 2.3µm pixels. The ASI294MM was actually "locked" in bin 2x2, to match the resolution of the ASI294MC, but in reality the sensor is a 47 MP one. That seems like a nice option for short focal lengths lenses/scopes! Thanks for the update. As it is, I won’t be using that feature in the nearest future. I come from 2.3 Mpixel and have now 12 Mpixel. My computer just can’t handle the increased data load of 47 Mpixel. It took me a whole evening yesterday to calibrate, align and integrate 344 luminance subs (8.6 hours worth of data). I wasn’t pleased with the result, so while I’m at work, my computer is integrating a new stack. A more powerful computer and more storage are on my wish list. 2.3 Mpixel was so easy... Link to comment Share on other sites More sharing options...
Space Oddities Posted November 26, 2020 Share Posted November 26, 2020 Holy molly! Yes, I guess 47 MP is out of reach... Also I read that each file is 90+ MB... Link to comment Share on other sites More sharing options...
wimvb Posted November 26, 2020 Author Share Posted November 26, 2020 Just now, Space Oddities said: Holy molly! Yes, I guess 47 MP is out of reach... Also I read that each file is 90+ MB... Yes 16 bit/ pixel = 2 byte/ pixel, so 94 Mbyte. 11 images will fill 1 GB of a hard drive. I captured 378 luminance subs for my most recent project. What can I say, modern cmos thrive on many, short exposures. But it costs... Link to comment Share on other sites More sharing options...
Space Oddities Posted November 26, 2020 Share Posted November 26, 2020 True... At least storage gets faster and cheaper every day! I bought recently a small external drive of 4TB for less than 100€. Not the fastest disk around, but for archiving my old subs, it does the job well! Link to comment Share on other sites More sharing options...
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