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With the weather here in the UK being so bad recently, and with work commitments and other boring life stuff going on I haven't done much imaging lately, but I did finally manage to get out and grab some OIII data a couple of weeks ago to go with my old Ha data of NGC 1499 from back in September. The Ha data was from first light for the newly modded D5300 and Baader Ha filter.
We have an outdoor sports facility only a couple of hundred yards from our house, and annoyingly the ridiculously bright floodlights don't turn off until after 10pm on weekdays, so even though there was no moon to contend with, I had no choice but to wait until the lights were off before I could start shooting the OIII. I thought about shooting more Ha while I waited, but in the end I decided to shoot some short subs without any filter, just to use for RGB stars. I stupidly didn't use my IDAS-D1 filter, and the scope ended up pointing almost directly at a streetlight for all the RGB subs. The result was a stack that had a simply insane gradient running through it, and which made gradient reduction on the stack impossible, as it was changing so much between subs. In the end I had to run gradient reduction on each individual RGB sub before stacking, and then run it again afterwards! Thankfully I only shot 20, so it wasn't too laborious. In the end I had something which, despite having a really ugly background, did at least have useable stars.
As for the OIII, boy was the signal weak with this one. I'm used to dealing with weak OIII signals on the D5300a, but this one really took the biscuit! Thankfully J-P Metsavainio's tone-mappng technique allows one to get the sledgehammer out for such cases, so I was able to stretch it far enough to get something out of it (even if it doesn't yield any fine structural detail for the OIII).
So this is 23 x 8 min Ha, and 9 x 20 min OIII subs. Calibrated with Flats and Bias, and dithered aggressively. The stars are made up of 20 x 90s subs. Everything shot at ISO 200.
The usual gear was used, HEQ5 Pro Mount, SW 80ED (with FF/FR), guided with PHD2 and a Finder-Guider and Legacy QHY5. Captured with SGP, pre-processed in APP, and processed in PS.
I have to say, I really like having the stars in a separate layer in PS. So much so, this is how I'm now going to process all my images from now on. It makes things so much easier being able to adjust whatever I want and not have to worry about constantly protecting the stars.
I'm not actually finished processing this one, but I thought I'd post it up for now anyway, and update it later. I still haven't ran any noise reduction on it yet, so I need to do that next, but hopefully the final version will not look much different to this. I did have some fun playing with the colour on this one.
I have noticed today though, that it looks quite different on my work Dell monitor compared to my cheap Korean one from home. I think it looks a bit duller today, but I'm just not sure! What do you guys think, does it need more or less of something in particular? All comments welcome, I'm always looking to learn!
Just got a nice surprise!
In the plate solving that is automatically done when images are uploaded to Astrobin, I just noticed that in one of my California Nebula images (from 21 Dec 2017), there was also something identified as IC2005. Looking it up it turns out to be a galaxy that is apparently bright enough to shine through the red nebulosity.
So, here it is, lurking in the right end of the image (arrow). I also post a crop of the galaxy area (with IC2005 in the centre). I do not know anything about it - wonder if anyone does?
The image was taken with my ES 127ED refractor (@ FL 752mm) and a Canon 60Da. 18 x 8 min (so 2.4 hours) at ISO1600. Processed in PS.
NGC 1528 at 150x
Spent just under 45 minutes at the eyepiece, so ran up against the issue of field rotation (really for first time in my limited sketching experience) and realized the importance of not only anchoring features to certain areas within the eyepiece, but also (and probably more importantly) using the relative locations between 3 and 4 stars at a time to make as accurate a sketch as possible.
Not done any deep sky imaging for over 3 years. A few changes in personal circumstances have meant a new lease of life back into the hobby. So here's 80 minutes worth of 10 minute unguided Ha subs using an SX H36 camera through a Tak FSQ106 mounted on a Paramount MX+. Taken on Friday evening when I had to be up early on Saturday to get the train down to London to attend Astrofest. Calibrated the image with some flats, bias and darks taken on Sunday Morning.
Minimal processing (trying to remember how to use Pixinsight) so stacked in DSS, some basic stretching in PS. I'm happy I'm back in the saddle again. I think I'll try and add some more data to this one before the winters out.
Thanks for looking
This is a two panel mosaic (with central overlap) that has been waiting to get processed - for some reason my first attempt to process it reached a dead end where I was rather disappointed with the results and gave up. But with clouds and moon conspiring I have made a new attempt from scratch. Taken with my Canon 300 mm f/4 (@f/4) on my triple rig on the same night as the previously posted Samyang 135 and ES 127ED images, so 21 Dec 2017. Like my Samyang mosaic, this is an accidental mosaic created by a shift in framing after the meridian flip, resulting in a somewhat unusual framing. Stacked in PI and processed in PS. 76x3min @ ISO1600.
Here is my previous post with the little Samyang and 5" refractor:
Comments & suggestions most welcome