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  1. Hey-ho So then, just as i thought the DSO season was well and truly over for me until late August/early September, as it turned out last Saturday night (May 5th) was mostly clear, so i set about trying to finish the NAN image i had captured in Ha a while back (see thread below): So all i needed was some OIII. It's obviously not the ideal time of year to capture this i know, as it's so low on the horizon, but beggar's can't be choosers so i tried my best to make the most of the small amount of astro dark time available and just make the best of it. In the end i managed 9 subs, two of which were sub-standard due to passing clouds, but as is my want these days i still asked APP to stack them (using the Quality setting) and it didn't seem to affect things. So in total this is: Ha: 7 x 480s, 6 x 1200, 13 x 1200 (a little over 7 Hrs) OIII: 9 x 1200s (3 Hrs) RGB (with IDAS-D1 filter): 20 x 60s The usual Flats & Bias, stacked in APP and processed in PS. Gear used: Nikon D5300 (modded); SW 80ED (510mm FL); HEQ5-Pro; SGPro and PHD2. The RGB subs were used solely for the stars. I still need to get better at merging them with the NB channels, i'm not as good as i'd like to be at controlling them. Although in this instance, i did mask the stretching of them, and it definitely helped, but i need to practice this to get better at it. I think the fact that the RGB stack (even at just 20 mins) contained some nebulosity didn't help things. When it's just stars and nothing else, it's so much simpler to combine them. So this is just a Version 1 for now (i'll try an sSHO next). I used Ha for Red, OIII for Blue, and used one of Carboni's Actions to synthesize the Green channel. Then went round and round in circles trying to find a colour balance to my liking (on my rubbish monitor!) so i'd love to hear what you guys think. Too dark? Too much saturation? (i tend to do that, lol). I also couldn't decide on orientation, so have included two different ones. Which do you guys prefer? All C&C welcome. Don't hold back! I'm always looking for ways to improve. Clear skies!
  2. This is a mosaic from one camera and two telescopes on three occations. Background is done with a 700mm F6.5 apo but for the galaxies I used my Meade LX200-ACF plus 0.78x reducer. Each one of those got 26x15 min @iso200 with a modded Nikon D7000 and CLS filter. Mount is HEQ5 Pro, guided with a standalone NexGuider. Captured with DslrDashboard on Android tablet. No darks, flats or bias used. Processing with Registar, PS and Topaz Suite. Ragnar
  3. The Great Barred Spiral Galaxy ( NGC 1365 ) in the constellation Fornax edit: new version with new long exposure data ( 52 x 240sec ) and better dark subtraction / dithering to remove streaks in the noise and amp glow. This also allowed for a greater stretch revealing more faint data in the galaxy and small faint fuzzies in the image .. The Great Barred Spiral Galaxy ( NGC 1365 ) in Fornax ( please click / tap to see larger ) and below I have added a 100% crop of new version: ........ original image: NGC 1365 ( please click / tap on image to see larger ) ............... The Great Barred Spiral Galaxy ( NGC 1365 ) in the Constellation Fornax Below the equator, not seen from much of the Northern hemisphere, NGC 1365 passes very nearly directly overhead an observer situated near Cape Town, as Sir John Herschel was in November of 1837, or near Sydney, as I was, almost exactly 180 years later, when I photographed this “remarkable nebula” that is numbered 2552 in his book of observations from the Cape. Not called a “nebula” now, of course, this striking object is one of the nearest and most studied examples of a barred spiral ( SB ) galaxy that also has an active galactic nuclei resulting in its designation as a Seyfert galaxy. At around 60 M light years from Earth, NGC 1365 is still seen to occupy a relatively large area ( 12 by 6 arc minutes ) due to its great size; at some 200,000 light years or so across, NGC 1365 is nearly twice as wide as the Milky Way and considerably wider than both the Sculptor and Andromeda galaxies. This High Dynamic Range ( HDR ) image is built up from multiple exposures ranging from 4 to 120 seconds with the aim of capturing the faint detail in the spiral arms of the galaxy whilst also retaining colour in the brightest star ( the orange-red 7th magnitude giant, HD 22425 ). Also, scattered throughout the image, and somewhat more difficult to see, are numerous and far more distant galaxies with apparent magnitudes of 16 to 18 or greater. Mike O'Day ................. Identification: The Great Barred Spiral Galaxy New General Catalogue - NGC 1365 General Catalogue - GC 731 John Herschel ( Cape of Good Hope ) # 2552 - Nov 28, 29 1837 Principal Galaxy Catlogue - PCG 13179 ESO 358-17 IRAS 03317-3618 RA (2000.0) 3h 33m 37.2 s DEC (2000.0) -36 deg 8' 36.5" 10th magnitude Seyfert-type galaxy in the Fornaux cluster of galaxies 200 Kly diameter 60 Mly distance .................. Capture Details: Telescope: Orion Optics CT12 Newtonian ( mirror 300mm, fl 1200mm, f4 ). Corrector: ASA 2" Coma Corrector Quattro 1.175x. Effective Focal Length / Aperture : 1400mm f4.7 Mount: Skywatcher EQ Guiding: TSOAG9 Off-Axis-Guider, Starlight Xpress Lodestar X2, PHD2 Camera: Nikon D7500 (unmodified) (sensor 23.5 x 15.7mm, 5568x3712 @ 4.196um pixels) Location: Blue Mountains, Australia Moderate light pollution ( pale green zone on darksitefinder.com map ) Capture ( 22 Nov 2017 ) 6 sets of sub-images with exposure duration for each set doubling ( 4s to 120s ) all at ISO400. 70 x 120s + 5 each @ 4s to 60s total around 2.5hrs Processing ( Pixinsight ) Calibration: master bias, master flat and no darks Integration in 6 sets HDR combination Image - Plate Solution ========================================== Resolution ........ 1.328 arcsec/px Rotation .......... -0.008 deg ( North is up ) Field of view ..... 58' 8.6" x 38' 47.5" Image center ...... RA: 03 33 41.182 Dec: -36 07 46.71 ==========================================
  4. Hey guys Here's a quick WIP version of the Heart Nebula taken with my usual gear, the Nikon D5300a, SW 80ED, and HEQ5 Pro. So for this constitutes: 11 x 1200s and 3 x 900s of Ha (so 4 hrs 25 mins in total) 30 Flats 50 Bias As usual, stacked in APP and processed in PS. It's well placed here in the UK right now so I'm hoping to get some OIII in the coming weeks. I'm never quite sure how much to process these images. Aside from the usual stretching, apart from a mild amount of deconvolution, sharpening, and contrast enhancement that's all I tend to do really. I've also attached a false colour version using one of Carboni's actions. C&C welcome as always. Oh, and Happy Christmas everyone! (it's December now, it's allowed )
  5. Hi, Am intrested in astrophotography,but I couldn’t take a single picture with my D-SLR attached to my celestron astromaster 130 Eq telescope...I have Nikon D3200 and if I capture the sky with lens attached the picture is very noisy and not clear...how can I take pictures of galaxy nebulae etc.... thanks
  6. The Rosette Nebula and Cluster ( NGC 2237 and 2244 ) in the constellation Monoceros edit: updated 30th Dec with improved colour balance and slightly increased brightness ... ...... original: ( please click / tap on image to see larger and sharper ) Still a work-in-progress really... with only 10 x 4min exposures for the main 'lights' before the clouds came over. I will try to add some more data when the moon has gone I am still experimenting with how to get the best out of the D7500. With the very warm nights ( low to mid 20s all night ) the 'warm pixels' are very noticeable so I reverted to my old practice of in-camera dark subtraction. This worked quite well and produced a nice smooth noise floor in the integrated images - albeit at the expense of more exposures. ................. Identification: The Rosette Nebula ( NGC 2237 ) is a large, circular emission nebula in the constellation Monoceros. It surrounds a cluster of hot, young stars known as the Rosette Cluster ( NGC 2244 ). ( SkySafari ) NGC 2237, 2244 Caldwell 49, 50 North is up. .................. Capture Details: Telescope: Orion Optics CT12 Newtonian ( mirror 300mm, fl 1200mm, f4 ). Corrector: ASA 2" Coma Corrector Quattro 1.175x. Effective Focal Length / Aperture : 1400mm f4.7 Mount: Skywatcher EQ8 Guiding: TSOAG9 Off-Axis-Guider, Starlight Xpress Lodestar X2, PHD2 Camera: Nikon D7500 (unmodified) (sensor 23.5 x 15.7mm, 5568x3712 @ 4.196um pixels) Location: Blue Mountains, Australia Moderate light pollution ( pale green zone on darksitefinder.com map ) Capture ( 23 Dec 2017 ) 9 sets of sub-images with exposure duration for each set doubling ( 1s to 240s ) all at ISO400. 10 x 240s + 5 each @ 1s to 120s imaged ~ +/- 1.5hrs either side of meridian maximum altitude ~ 51.3 deg above north horizon Processing ( Pixinsight ) Calibration: master bias, master flat and in-camera dark subtraction Integration in 9 sets HDR combination Image Plate Solution =================================== Resolution ........ 0.633 arcsec/px ( full size image ) Rotation .......... 0.181 deg Focal ............. 1367.90 mm Pixel size ........ 4.20 um Field of view ..... 58' 59.4" x 39' 15.0" Image center ...... RA: 06 31 55.638 Dec: +04 56 30.84 ===================================
  7. Hi All, I was wondering if anyone has any experience comparing DSLRs with 12bit pixel depth like canon 700D vs 14bit like Canon 800D. Might it be worth upgrading your existing 12bit model for a 14bit model. Also what about the question of a cooled 12bit CCD like the ZWO ASI1600 compared to a 14bit DSLR? Cheers!
  8. Hi, When doing color images from DSLR color cameras it could be a bit frustrating to find correct color balance. If you could get to know your DSLR camera's own RGB scaling factors it could be a starting point how to set the scaling factors. With the tool DCRaw you can get these values. Here is a tutorial I have wrote how to use DCRaw to find these values: http://www.astrofriend.eu/astronomy/tutorials/tutorial-rgb-multipliers/tutorial-rgb-multipliers.html I have only use it to my own Canon DSLR, but should work on all cameras that DCRaw support I think. /Lars
  9. My setup: Telescope: Skywatcher ED80 Camera: Modified 700D Guiding: QHY5L-ii m + finderscope Image Capture: Astrophotography tool Processing: DSS + PS or Pixinsight Filters: Astronomik CLS clip on Over the last week I managed to get two nights with the telescope, both of which were spent capturing the iris nebula. On the first night I got about 1.5 hours and on the second night I managed a whopping 7.5 hours. I give thanks to the recently purchased 700d AC power adapter for that long stint. I live in a relatively light polluted area, but I can still manage to see the milky way on a clear night. Now, I usually image relatively easy images ... orions nebula, horsehead nebula, rosette, heart and soul, using the above setup as well as with the canon 200mm lens. The iris nebula on the other hand I wouldn't consider as easy a subject as the rest, given my FOV and the fact that most of the interesting artefacts around the nebula consist of VERY FAINT dust lanes. In any case, I decided I wanted to take the leap and just go for it. A concern of mine was the colour of the stars; I wanted to make sure that I didn't clip any of them, and so I decided to expose my subs to accommodate this, which lead me to 240s subframes at ISO1600, dithered. This is what the histogram looked like for one sub: And this is what a single sub looked like without any processing/calibration: The stars seemed sharp enough and I had both the Iris in view as well as the ghost nebula (just about) keeping it company. My train of thought has always been that even if a single sub doesn't show the detail I'm after, stack enough of them and it'll soon appear. I went ahead and captured the images, got the corresponding flats, darks and bias frames and then ultimately started to process the images. This is what the histogram looks like in PI before and after I apply the DEFAULT screentransferfunction curve: And this is what the image looks like, without any post-processing other than Automatic Background Extraction and a 180 deg fast rotation: There are a number of things that concern me about this image. The colour motle/noise what ever you want to call it. There are blotches everywhere. The level of luminance noise which for 8+hours worth is simply disappointing. The lack of detail in the dust lanes. I come back to the title of this thread: Where did I go wrong? I apologise for the length of this post, I was just trying to be thorough.
  10. Hi! I would just like to ask if it is possible to get a decent image of the Rosette Nebula using an unmodded DSLR. I'm planning to take a series of around 120~150 secs shots. Thanks!
  11. Hi guys So we had a completely clear night last Thursday and, as luck would have it, i was actually off work all week, so i was able to take full advantage. Well, mostly, as you'll soon find out. As it turned out this was a night that almost went completely awry. The first thing that i messed up was i forgot the external battery that keeps the D5300 powered all night. I only noticed this after driving the 45 min trip back to the family home where i do my imaging. Doh! Luckily though, i dipped into my big bag of astro stuff and found the 2 old camera batteries and charger that i used to use. By my reckoning it was last December when i last used them, so i was amazed to find they still had quite a bit of charge in them! So i was able to charge one while i used the other. Unfortunately though it meant i had to keep going out to the scope every 2-3 hrs to change battery, but tbh i was just relieved that i didn't have to drive home and lose another 90 mins of dark sky time. The next thing to grumble was the guider. For some bizarre reason, i could not see Polaris in the Fov in Sharpcap. I could barely see anything at all tbh so even though Sharpcap told me it was able to platesolve i was very dubious. And then when i came to do the Sharpcap PA routine, the adjustments were jumping around all over the place. It took me about 25 mins to PA instead of the usual 5, and i really thought the guiding was going to be a nightmare, but what do you know, it turned out to be actually really good. It even dipped below 0.5" at times. Go figure! Due to the floodlights of the sports facility (which is rather conveniently only about 100 yards away from the house) i was forced to start with Ha subs, then once they were turned off at 10pm, i switched to Oiii, as i knew the moon was coming up around 00:30 so i needed to take advantage of the darkest part of the night. I figured i'd go for about 3 hrs of Oiii, knowing that with the final filter change back to Ha again, i should end up with about 4-5 hrs of Ha in total. Well, after doing the last filter change and going back in to grab a nap for a couple of hrs, when i woke up and checked Team Viewer i noticed that the sequence had unexpectedly ended. Went out and saw that the 7 Ahr LifePo4 battery i use for the mount had died. I also noticed that the lens of the Finder-Guider had completely dewed up. As it turned out, the dew strip for it had failed so i've had to order a new one. I've also ordered a PSU to power the HEQ5-Pro from the mains, so fingers crossed i shouldn't have to worry about mount power over the winter now. All in all this was a bit of a pain of a night, as i normally only shoot 1 filter per night. Sometimes in the longer winter nights i might do 2, but i've never done 3 before. It's a real hassle too, as i need to shoot flats, change filter, re-frame and re-focus. All of which can take upwards of 30 mins. Hmmphh. So long story short i didn't end up with as much Ha as i wanted for this, which has meant it's been trickier to process than i would have liked. I should probably have just waited and done another night of Ha, but with all the hassle i have to go through to get any imaging done these days (drive, setup, tear down and pack away, drive home, sleep deprivation) i will always just try and use what i've got and move on to the next target. The Mean ADU level was quite low on this one, probably because the target is quite small and only occupies the centre of the frame. I've probably been lucky up to now, by mostly shooting larger targets, so i was disappointed with the low ADU levels, which are scraping the bottom of the barrel for me in terms of getting away from the noise floor. So i upped my exposures a bit, pushing as high as 25 mins, which is the nighest i've ever gone with the HEQ5-Pro. It seemed to still handle it quite well, although it didn't improve the Mean ADU level anywhere near enough. Full capture details: 3 x 1200s, 2 x 1380s, and 4 x 1500s of Ha 9 x 1200s of Oiii. 11 x 480s of RGB (with an IDAS-D1). Used for the stars and sky background only. 7 Hrs 54 Mins in Total. All shot with a Nikon D5300, SW 80ED, and an HEQ5-Pro. The RGB data was shot over a year ago from inner city Belfast (Red Zone) while i was testing out the new Rowan belt mod. It was just a test shot to check the guiding, so the 8 min subs were far, far too long in reality, hence a lot of the medium and bright stars are clipped. But i have to say, the IDAS-D1 together with APP did a nice job of cleaning it right up and making it at least useable (well, by my standards at least!). So on to processing. I've been playing with this for several nights now, and i just can't look at it anymore! i think this is the best i can manage with the limited data i have. It's been enjoyable and yet frustrating at the same time, lol. As usual, this has been stacked in APP and processed in PS. I used the tone-mapping method of processing, and created a synthesised Sii from a 50/50 blend of the Ha and Oiii. I then combined them in the classic Hubble Palette SHO. Obviously, not having any real Sii means i can never get the full range of tonal variations throughout. I'm also not completely happy with the colours if i'm being honest (especially the blue). That was the part i struggled with the most on this one. I've also attached below a quick and dirty HaRGB version, which took me all of about 30 mins to process (in total contrast to the SHO version, which i won't say how long it took!). As always, constructive criticism welcomed with open arms! Ok time for me to stop rambling on now ? Edit - Forgot to say, I resized the sSHO version down to 75% of the original (it's not worthy of 100% viewing).
  12. Hi everyone, I recently decided to get a 70-200 f2.8 lens or similar (liek 80-200 nikkor) to mount on my Nikon D3300 and Star Adventurer, because as a landscape photographer I feel I will use way more a tele lens than a telescope. It will be a graduation present, so I hope no budget limit. My question is: which lens to choose? In order to capture some extra details I'll most likely add a teleconverter 2x if the choice will be a 70-200, otherwise I'm considering a 100-400 Sigma or Tamron but I can't find anything about how they perform. Thanks for your advices.
  13. HI All, I have an entertaining video to share with you which is perfect for those just starting out and wanting to taste a bit of astrophotography without spending a lot of money. I image from London and managed to get a pretty good shot of Orion for just £150. This video runs through where I bought the equipment, why I bought it and how I used it to capture a Orion and some of the trials and tribulations I had to deal with on the way. Any questions please ask! Enjoy! FYI I shot this last year but with Orion now beginning to rise over the rooftops of London I thought this would be a good time to share it.
  14. Hi, I have a Canon EOS 1000d, which I modded back at the start of the year. I usually capture subs of about 3-5mins duration at ISO 800. However, I'm wanting to image the Deer Lick group with Stephan's Quintet, and I'm going to need to go right the way to 5 min subs for them. I've noticed quite high noise levels at ISO 800, is this the optimal speed to use? Would it be better to capture subs at ISO 400, or would they then be really underexposed? Would I be better doing 3 min subs at ISO 1600? I find ISO a little bit confusing, as far as I know it's a measure of how the camera's computer assigns brightness from the raw pixel values? ? Thanks for looking! John
  15. Hi all,just wanting to pic someone's brains.. As normally with a DSLR imaging during a full moon seems to be a waste of time and as a Ha filter cuts throu the l.p. a little,is it possible to do some HA narrowband imaging with a DSLR? I have a 12nm Ha filter,would that work or does the bandwidth have to be narrower to cut the l.p. out.. so it be like a Ha,rgb image..Or is this just for the ccd owners?
  16. Hi everybody!! Just joined after lurking for a year. I have done the filter removal as instructed by Gary Honis and was satisfied with the results. Only one thing I'm wanting to learn and that's how to do a cold finger mod on my canon 1000d. I have found some links, but mostly any instructions I've found were outdated and removed from the web, so it's been difficult to find a mod to my liking with detailed step by step and supply list. One of my main concerns is that I still want to use the side of my camera that has usb and the input for my intervalometer (currently unguided with no laptop). I can do without live view as long as I can still connect the dslr to my phone on dslr controller for a bigger more comfortable live view. Anyways I really need help in the right instructions to get this done. Any links, videos, or experienced instructions would be a big help and I would be very thankful for. I'd also like to add that I would like to go light weight on the mod, so i don't have much trouble balancing the es 80mm triplet on an Orion sirius. Trying my best at a budget to defeat the Texas summer. Clear skies!
  17. Hi all, I've just managed to get hold of a second hand 350d which has been modded, to use for some wide field work. I don't know whether the sensor was shimmed at all - so don't know whether it'll focus without an additional filter in place. On the assumption it wasn't moved (and with no lens as yet to try it with!), does anyone know if the Astronomiks Clip filters provide enough compensation in the optical path to allow a prime lenses to come to focus? I was thinking about using a UV/IR or CLS there to help everything out, but would be handy if anyone can confirm.... Cheers!
  18. I'm want to get into AP iamging DSOs but have focusing issues - nothing new there I guess. My basic question is this: Is it possible to use a DSLR and USB link to display live images on a Windows PC (or Android Tablet) with sufficient resolution to use a Bahtinov grating for focusing? If so, which DSLR have people used in this way? And which software? I have been trying without success to use my Sony A300 DSLR but the built-in LCD display is far too low resolution to see the fringes from a Bahtinov grating. The grating works great with an eyepiece so nothing wrong with the grating. And the Sony video out is of similar low resolution to the LCD display. And unless I'm missing a trick (please tell me if I am!) there is no way to get live images over the USB link. As a very poor second best, is there any single software (for Cannon, Sony, whatever) that will allow triggering of images (Bulb mode) and upload the image almost immediately. I guess I could live with that just so long as I end up with a properly focused system. My scope is a 6" f10 CS. And yes, I know f10 is too slow and I need a field expander but it's where I'm at at the moment. And unless I can crack the focusing all other issues are secondary. Many Thanks for reading this far! Geo
  19. They said it couldn't be done! I won't pretend this is perfect but it's 90% of 106 2 minute subs on as astro-modded Canon 450D DSLR using an EQ3 mount at a suburban location, and the transparency last night was poorer than the previous evening. NGC133 and its dust clouds are NOT supposed to be the sort of target you can get with this kit. I know it isn't perfect and doesn't stand up to images with double-figure hours of narrowband subs, but it does have the dusty bits in the right places if compared to Olly's recent image. If I had 20 hours of subs at a dark sky site what would this image be looking like?
  20. Hello all Let me explain my desire and what I'm hoping to achieve. I do not have a dslr so whatever I buy will be my first Astrophotography camera. What I'm hoping to achieve is some good deep sky photos but I wouldn't mind also doing some of the planets as a secondary thing. I have also seen the webcam type imager like the revolution r2 imager which seem to let you see deep sky opjects directly on a screen. Any good? Please can people give their experiences of what is achievable CHEAPLY is the key word. I have also seen that the ASI 120mm is a good camera but seems geared more to planetary. Many thanks to all Gerry
  21. Hi all! It's been a while since I wrote here, also because this year I've been less active in the field, unfortunately... Anyway, I've now started to do autoguiding, with mixed results. I bought myself a laptop and guidescope, with CCD. I'm able to do 10 minute exposures that come out fairly well most of the time. Guiding is mostly good. I tried PHD as well as Maxim, but lately Maxim seems to be doing better, or I just found the sweet spot for my setup. The last 2 or 3 times however, I'm having difficulty in obtaining decent images. Even with no moon, the images I get are quite bright, with stars barely visible, and the stack is terrible: it's a light shade of grey, hiding all stars (let alone a nebula), and the histogram shows the peaks (in DSS) far to the right, so adjusting that is a nightmare, so much so that the last two times the result was not worth showing to anyone.... The site I go to is always the same, and I already obtained quite nice images, also with 10 minute exposures and the same ISO... Apart from this, I'm having a very hard time getting my flats right... I've got a "flatbox" (EL panel with two sheets of white paper, 8 sec exposures at 800 ISO, the same ISO I use for the Light exposures) that I tried at home in the dark with the scope and camera, to get the right histogram, as I gather looking online: the peak should be at about a third of the histogram. Problem is, which I discovered only last week, the histogram changes with the same setup, for the various "receivers" of the flat image: the camera, Maxim, or DSS. As shown in the photos below (the camera is a RAW picture, taken with the same settings as the FIT picture I used for the DSS and Maxim screen caps): camera: DSS: MAxim: Apart from the histograms, I also always get those very ugly red hue photos in Maxim.. Is this something of Maxim, or am I getting something wrong?? The image obviously is not red, but the grey shade of the DSS photo (the photo of the camera screen shows only white, but that's because of the phone cam)... This means I can never check in a decent way if the exposures are coming out right while I'm taking them with Maxim... So, recapping, problems getting the flats right, and headscratching about the bright exposures I'm getting lately from a setup that already proved it doesn't have to be that way... At the moment I don't have examples of the latter problem to attach (because I didn't finish any stack, seeing as they came out so horribly), but I can attach some, if needed. Any suggestions? Somebody had the same problems? I'm getting a bit frustrated, I must say... Clear skies!! Gerhard.
  22. Last night was a bit of a miracle, there was more clear sky than predicted! I set everything up at dusk expecting to be able to do nothing more than practice polar alignment, but I actually managed to get some imaging in as well! Admittedly I had to spend the first half of the night fighting SGPro in order to convince it to actually let the guider settle before opening the shutter again. The first hour of subs needed to be thrown away as they all had lines where PHD was trying to bring the guidestar into the right place after dithering, but SGPro has waltzed on ahead. It turns out that the integration of Sequence and Equipment Profile in SGPro is unclear and byzantine. I managed to capture some of the dark dust surrounding the brighter nebula which I am pleased about. There is still a bit of a gradient from top to bottom, but I could not decide if it was more dust, so I decided to leave it in. The centre of the nebula is completely blown out unfortunately, I tried to take some shorter exposures, but even at 60 seconds, the core was blown out and I was getting no nebulosity at all. Lights: 21 x 300s @ ISO400 Darks: 112 x 300s Bias: 492 Flats: 54 x 1/8s C4 - Iris Nebula by frugal10191, on Flickr Mount: Skywatcher AZ-EQ6 GT Imaging Telescope: Skywatcher ED80 DS-Pro with 0.85x FF/FR Imaging Camera: Canon 60D (Unmodified) Guiding Telescope: Skywatcher ST-80 Guiding Camera: Starlight Xpress Lodestar X2 Software: Sequence Generator Pro, PHD2, PixInsight I also tried to image the Elephants Trunk as some people have had success with unmodified DSLRs, but the 10x300s subs I managed before the clouds rolled in show no signs of nebulosity when stacked ;(
  23. Members, Trying to get my head around imaging with a DSLR and read that a WEBCAM is actually better for planetary targets due to file size and weight therefore, can I hypothetically use a DSLR afocally but on the record video setting and still separate the frames afterwards, edit and stack? Or would they be too large? 9.25 AVX with Canon 550d Rebel2.
  24. Hello all, I have been taking photographs from a static tripod for awhile now with varying success, mostly landscape shots using a wide angle. I now have an unexpected £300 to potentially spend on an EQ mount but am struggling to understand if that is the best way to progress to the next level. For Christmas my girlfriend bought me the Opektra 500mm (with 2x teleconverter) so I could hopefully take some pictures of planets (It's not a great piece of glass basically a cheap telescope with a t-mount fixed at f/8 with manual focus, but it's okay for what it is). I immediately found it virtually impossible to get anything to stay in the FoV with my tripods as (obviously) the slightest movement on such a small object threw it out, the best I was able to manage is the attached image. From the research I have done it appears that a mount is more important than a telescope in some respects, as I need something that can hold the weight of my camera and track over a longer exposure. I have a Nikon D300 and the following lenses in addition to the Optekra; Nikkor 17-55mm f/2.8 Nikkor 70-300mm f/4.5-5.6 Nikkor 70-200mm f/4.5-5.6 Nikkor 50mm f/1.8 Nikkor 35mm f/1.8 There is a live view function on the D300 but no video. Any suggestions on what equipment to progress to gratefully received (as are any links to good guides, I'm not adverse to reading but am struggling to find anything around next steps that don't involved spending thousands on a telescope and a mount) but also if I am better off just continuing to save and can improve my existing kit in the meantime I would really love to learn how! Many thanks in advance for any help.
  25. Hi, I have been looking for parts for my new telescope project, I have spent much time on finding the little more special parts. I think it could be usefull for others and have written down the links to vendors and manufacturers of equipment of astronomy I have found at my website: http://astrofriend.eu/links/links.html Most pages have an "English " button. I hope it will be usefull for your special astronomy project ! I will add more links later. I wish you all A Merry Christmas and a Happy New Year! /Lars
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