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Paramount

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Posts posted by Paramount


  1. Hi all

    Ok, so it isn't the owl and the pussycat but I couldn't resist a play on words. I have never tried M97 before and as a planetary nebula I knew it would be ok for narrowband imaging. Given the sky conditions last night it was ideally placed, ie high up near the zenith. Originally I was only planning Ha and OIII as I had looked on other sites and not many people had used SII (perhaps because there was virtually none). I hadn't planned on getting M 108 but when composing the image saw that it was in the same shot so I got 2 for the price of 1. I had originally planned on 12x10 minutes unguided for each filter which is what I shot but during the session there must have been some patches of icy moisture in the atmosphere as a few subframes were ruined for each filter. At the end of the session I still had about an hour left till day light so I shot one SII frame and saw that there was something coming through although much fainter than Ha and OIII so I left it running and got 4 useable subframes. This is the end result with 8x10 minutes for Ha, 7x10 minutes for OIII and 4x10 minutes for SII combined as SII:Ha:OIII = R:G:B with a weighting of 3:3:1. Taken with the Takahashi BRC-250 and H36. There are two close up cropped images of the galaxy and nebula themselves on my website http://www.imagingtheheavens.co.uk which show these objects in greater detail

    Thanks for looking

    Best wishes

    Gordon

    Owl.jpg


  2. Hi all

    Finally managed to get out and do some imaging last night, not completely problem free though, after about an hour during a long session from 7pm to 7am I had some condensation on the camera optical window so I had to take it off and give it a blast with my girlfriends hair drier for five minutes, then had to refocus so half an hour or so wasted. Clear sky all night although imaging low in the sky was out of the question due to misty sky, the moon was high up as well which meant lots of sky glow and the ability to do my Telegraph crossword without artificial lights. Any way enough of the excuses.

    I had originally planned to do this in colour but after starting the OIII something didn't look right in the image and I eventually tracked it down to condensation on the camera window, once I had sorted this out and refocused the subject was heading towards the mist so only Ha for this one I'm afraid. It is 8x10 minutes unguided with the Takahashi BRC-250 and Starlight Xpress H36. The image is cropped as there is now some vignetting in the corners since putting the PDF focuser in the image train (that is a small sacrifice to pay). Simple auto dark subtraction was used in Maxim DL, no flats or bias frames were used

    Thanks for looking

    Best wishes

    Gordon

    cone.jpg


  3. Hi all

    I have been dying to get out and try my new scope and finally lastnight there was some clear sky to give it a try. Focusing was very difficult as the BRC-250 uses a helical focuser and when you turn it the camera assembly moves as well and as the scope was a long way from near focus this meant alternating between the focuser and the instrument rotator in order to stop the cables from twisting up. The focuser is very smooth but at the same time very firm so it takes a bit of turning. It took about half an hour just to get focus. Because of the camera rotating I didn't use my usual method of using one star to focus on in Maxim DL and using the inspect tool, instead I did it visually using the difraction spikes on a bright star as a guide (when out of focus the difraction spikes were split) so please excuse the image if it appears slightly out of focus. I am waiting for an adapter to fit my FLI PDF focuser in the system and when that is in things will be much easier as I can get close to critical focus with the helical focuser and then lock it it and leave everything to the PDF focuser, so at the moment the camera is not the correct distance from the built in field flattener. Anyway, enough of the excuses. I managed 8x10 minute unguded subframes of IC 410 of which 4 were ruined by cloud and after the 8th subframe that was it for the night as the clouds stayed. So this is a 4x10 minute image in Ha only. Only simple auto dark subtraction was done and no flats were applied. I have included the full widefield and an extreme close up of the Tadpoles themselves

    Thanks for looking

    Pictures of the BRC-250 can be seen on my website http://www.imagingtheheavens.co.uk

    Best wishes

    Gordon

    IC410.jpg

    IC410crop.jpg


  4. Hi Trevor

    That is a very nice image considering how faint it is and to be honest with you a DSLR is perhaps not the best tool for the job especially one that isn't modified and contending with light pollution so you have done very well there. It is certinly far better than my first effort with this subject and that was with a ccd camera. Keep at it and as has already been said you will continue to come on in leaps and bounds

    Best wishes

    Gordon


  5. Hi

    I think you may also have some serious and strange problems with the tracking on your mount, some of the stars are round while some of the larger ones in the foreground have distinct trailing. It should be easy to "track" down the problem as the trailing is in one direction. Did you check the polar alignment and aggressiveness of the guiding corrections?:biggrin:

    Best wishes and Happy New Year

    Gordon


  6. Hi Ray

    Thanks for the comments, As far as I am aware it isn't visible through a telescope unless you have access to a fairly massive aperture. Even with 10 minute subframes for Ha, hardly anything shows up on the downloaded image, this is quite a faint object. It is one of those subjects that I am going to be having a really serious go with when I get my Takahashi BRC-250 set up as with the extra aperture, longer focal length and faster focal ratio of f5 it should produce a real corker for this object

    Best wishes

    Gordon


  7. Hi All

    About 3 months ago I posted a narrowband image of "The Elephants Trunk Nebula" - IC 1396 in the HST palette. Well I had an early Christmas present yesterday when I received an email from one of the editors from APOD to tell me that it is going to be the featured picture for Boxing Day. As you can imagine I am over the moon. It really makes the long cold nights outside a small sacrifice to pay. I have posted the image below, thanks for looking (yet again!). Merry Christmas to all

    Best wishes

    Gordon

    vdb142(1).jpg


  8. Hi all

    I would have to say that this is a case of the grass is not always greener on the other side. Oh yes it is! No its isn't! Yes it is! No it isn't!.......

    What I am trying to say is that both hemispheres have some real jewels for observers and imagers alike, up north we have the heart and soul nebulae in Cassiopea, M51, the Pacman nebula, the bubble nebula, etc. Down south you have Omega Centauri, Eta Carina, the tarantula nebula. Unless you have access to telescopes in both hemispheres then you join forums such as this and marvel at what other people are producing in the same way that other people marvel at what you produce. At the end of the day I don't think North is better or South is better, they both have their qualities

    Best wishes

    Gordon


  9. Hi Ray

    I use the Starlight Xpress H36 16 mega pixel large format camera and am very happy with it. There is a lot of misconception that large format cameras need a big scope and therefore a big mount. This is incorrect, a lot of people are using these cameras with scopes such as the Takahashi 106 f5 (New Q as it is sometimes called) and even smaller. I use mine with a TMB 115 f7 and soon to be arriving BRC-250. These are relatively medium sized scopes. The main issues that people have mentioned about vignetting, distortion, coma, field curvature, etc are the real issues and all of these can be overcome quite easily even without using flats. Regarding vignetting, you must ensure that all the adapters you use have maximum diameter aperture and to this end I deal with precise parts http://www.preciseparts.com in America, they can make any adapter to any specification, they are quick, efficient and Ashley Stevens is very helpful. A field flattener will deal with the field curvature problem and I use a custom one from APM for my TMB (custom in that it is designed specifically for my TMB 115). This in conjunction with the precise parts adapters, H36 camera, FLI filter wheel work perfectly with no field curvature and no vignetting. The Takahashi BRC-250 f5 that I have on the way has a built in field flattener/reducer that gives a flat imaging circle of 100mm (more than enough to cope with todays large format cameras). I have been imaging with my TMB 115 f7, FLI filter wheel, flattener, H36 combination for almost a year and am still learning yet none of my images have had flat field frames applied.

    Out of the three cameras it is difficult to choose, regarding the SBIG with its on board guiding chip, this is fine until you want to do narrow band imaging which renders the on board guider useless as you may not be able to find a guide star because the filter will prevent very short exposures, also having a built in filter wheel is nice but the more gadgets and the more there is going on in a piece of equipment the more there is to go wrong, and if something goes wrong with say the filter wheel part of things then the whole camera has to go away for repair.

    I don't know enough about the QHY cameras so I think it would be unfair for me to comment on them. The starlight Xpress is a different kettle of fish though as I only use them. From a price point of view they are cheaper for the same chip camera than SBIG and FLI, the after sales and customer service with SX is very quick, friendly and efficient so they certainly get my thumbs up. Sure, the FLI has more facilities such as more sensitive chips, manual contraol over cooling, etc. but the equivalent chip camera to mine would cost me about £9000 in the UK compared to £4500 that mine cost me.

    Best wishes

    Gordon


  10. Hi Ray

    For me I would have to say the Nagler 31mm 82 degree field of view for widefield use as it just makes you want to step into the eyepiece. It is amazing on every telescope. For higher power you can get no better than an Ethos 17mm 100 degree field of view. I don't do a great deal of observing but earlier this year after an all night session of imaging the sky was just starting to get too light to image and I put the Ethos on my C14 and turned to Saturn, the view through the eyepiece just took my breath away. In the same field of view you could see Saturn in all its glory including the cassini and enck divisions in the rings, banding on the planet itself and six of its moons all in the same shot. The image was so tack sharp and 3D that I almost had to question whether it was fake or not. Apart from my illuminated 9mm reticule eyepiece that I use for polar aligning these are the only two eyepieces that I own and as I don't drive and travel everywhere by public transport I always take them to star parties where they are gratefully welcomed by whoever I ask to have a look through their telescope

    Best wishes

    Gordon


  11. Hi All

    Well, I have finally taken leave of my senses, I knew it was going to happen sooner or later what with with all these sleepless nights. I know that narrowband imaging is more associated with emission nebulae, SNR, planetary nebulae and the like but I decided to do this as an experiment while I was waiting for IC 443 to come from behind my house. The moon was almost full so the sky was very bright and as I already had the emission line filters loaded in the filter wheel (LRGB set is still in the boxes), so I did 6x10 minutes unguided for each filter and combined it SII=Red Ha=Green and OIII=Blue (HST palette). Although I wouldn't recommend people spend valuable imaging time taking pictures of star clusters with NB filters I am always wanting to try new things even if they don't sometimes work, I am reasonably satisfied with the way that this has turned out although some of the colours are a bit more muted than what I have seen elsewhere. I last did this late last year with a WO 66 and Starlight Xpress M8C and this image can be seen for comparison in the star cluster section of the image gallery on my website http://www.imagingtheheavens.co.uk

    Further details about the equipment used is also on my site with the image

    Thanks for looking

    Best wishes

    Gordon

    perseus(2).jpg


  12. Looks amazing. What is that bright star below it? I can't tell that you didn't get enough data. It looks fine to me.

    Brett

    Hi Brett

    Thanks for the comments, the bright star just below the nebula is Propus, or eta Geminorum as it is also called. This is one of those subjects where you need plenty of OIII and SII data to get the best out of the images as the subject is dominated by mainly Ha, the other two channels need boosting which is why more data is needed

    Best wishes

    Gordon


  13. Hi All

    I took this in the early hours of Wednesday morning and was aiming to do 6x10 minutes Ha, 12x10 minutes OIII and 12x10 minutes SII, all unguided, but as is usually the case the British weather and a neighbours tree hampered my plans. The Ha data went fine, then some cloud knocked out two of the OIII subframes and I forgot how low IC 443 was getting in the sky and it hid behind a neighbours tree after five of the SII subframes. Due to this I wasn't able to get as much SII as I wanted so this is a temporary picture until I can. I first tried this subject with just a ligh pollution fillter in monochrome and then added false colour earlier this year, it was one of the first shots I took with my TMB and H36 (no field flattener at the time), this image is in the nebulae section of the image gallery of my site http://www.imagingtheheavens.co.uk for comparison. Only simple auto dark subtraction was used to callibrate, no flats.

    Thanks for looking

    Best wishes

    Gordon

    IC443(1).jpg


  14. Hi Brett

    Thanks for the comments, I had an email from Richard Crisp of http://www.narrowbandimaging.com who gave me some useful tips to bring out a bit more detail in the OIII and SII data while making the Ha a bit less green and predominant, so I had a go at tweaking the levels, curves and colour balance and came very close to what he showed me, I certainly think it is better but it has introduced some noise into the image which is more evident on the full resolution image, anyway here it is for comparison

    Best wishes

    Gordon

    IC1318a.jpg


  15. Hi All

    Just been catching up on some processing and tweaking of images. I took this image of IC 1318 earlier on when Cygnus was more overhead. It is taken with 6x10 minute unguided subframes per filter using Ha, OIII and SII in the HST palette, there certainly is a lot going on in this region as far as nebulosity is concerned and this image only covers a small area of it. Sadr is the bright star in the middle. I took a Ha only image of the same region earlier on and this can be seen in the nebulae section of the image gallery on my website http://www.imagingtheheavens.co.uk for comparison

    Taken with TMB 115 and Starlight Xpress H36

    Thanks for looking

    Best wishes

    Gordon

    IC1318(1).jpg


  16. Okay Gordon, times up mate. What kind of spaceship are you travelling in to get such close up shots?:biggrin:

    Very nice colour balance. I almost feel like I'm there.

    Ray

    Hi Ray

    Thanks for the comments, these are quite large objects, what you see is the full field of view with my TMB 115 and Starlight Xpress H36 apart from some slight cropping to get rid of the effects of stacking

    Best wishes

    Gordon


  17. Hi All

    I recently posted seperate images of the Soul nebula (IC 1848) and the Heart nebula (IC 1805), following comments on some forums that the images were a little on the green side and not enough red showing through, and somebody mentioning that it would be nice to have the two together. Well I have tried to kill two birds with one stone, I have done some more processing on both images by tweaking the levels for each channel and some minor adjustments in the colour balance to bring the red out a bit better and ease off on the green slightly. There is a trade off to this though in that the stars are much pinker in colour which is an inherent problem with using the HST palette. I have posted both images here (not as a mosaic I'm afraid), you can compare them with the originals on my website http://www.imagingtheheavens.co.uk, at first I wasn't sure whether I liked these versions better or not but after direct comparison in photoshop I do.

    What do you think

    Best wishes and thanks for looking again

    Gordon

    IC1805repro.jpg

    IC1848repro.jpg


  18. Hi all

    Last night was absolutely freezing but at least the sky was clear, I managed to get 2 hours for each filter in 10 minute unguided subframes before it sank too low in the sky.

    It was taken with my TMB 115 f7 with matching field flattener, FLI filter wheel with astronomik Ha, OIII and SII filters, Starlight Xpress H36 camera and Paramount ME. I used simple autodark subtraction in Maxim DL and no flats or bias frames were used. It was combined as an RGB image using the HST palette with a weighting of 3:1:2 for the respective RGB channels.

    I have posted the full widefield image here but I have posted a couple of cropped closeups on my website http://www.imagingtheheavens.co.uk to show the central core of the nebula and also the "Ghost Nebula" in more detail

    Thanks for looking

    Best wishes

    Gordon

    IC1805.jpg

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