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GordonH

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Everything posted by GordonH

  1. Hi I started this a few weeks ago and managed to shoot 15x10 minutes each for RGB. It was clear again last night so I shot 24x10 minutes for luminance just finishing before the half moon got up too high. The dark nebula and dust which my neighbour said looks like a "Hoodie" was very faint and difficult to process out (not helped by the light pollution where I live but luckily the object is high at this time of year). It was taken with a Takahashi FSQ106ED at f5 and FLI ML8300 on a Paramount ME auto guided by a Lodestar and OAG using dithering. This is certainly a colourful area of sky with stars of varying colour and the blue reflection nebula. Below is a link to the full size high resolution image Van den Berg 149/150 and LDN1235 photo - Gordon Haynes photos at pbase.com Thanks for looking Best wishes Gordon
  2. Hi All The sky was clear for a few hours the other night, but as the moon was up I thought I'd have a go at star clusters so I decided on the double cluster. This was taken with a Takahashi FSQ106ED at f5, FLI ML8300 at -35c on a Paramount ME autoguided by Lodestar and OAG. Red 30x5 minutes Green 29x5 minutes Blue 25x5 minutes The discrepancy between the number of sub frames was because of a meridian flip (at the end of the green run) and mist and cloud after 25 frames of the blue run RBI annihilator was used for the raw frames and matching darks but not for the flats and their darks as the short exposure times negate the necessity for RBI resolution. Processing just consisted of levels and curves and gradient removal I have done a wider field version of this last year which can be seen on the star cluster page of the image gallery on my website Imaging The Heavens - Home Page for comparison The full size high resolution image can be seen at the following link NGC869 and NGC884 - Double Cluster in Perseus photo - Gordon Haynes photos at pbase.com Thanks for looking Best wishes Gordon
  3. Hi I posted my first image with my new ML8300 last week and after getting back from the Kelling Heath star party I managed to get out last night and take some RGB data to go with the Ha. The transparency wasn't very good last night due to a thin haze but nevertheless I am happy with the way this turned out. It was taken with my Takahashi FSQ106ED at f5, FLI ML8300 (cooling set to -35c) on a Paramount ME, autoguided by a Lodestar and OAG. It is 8x30 minutes for Ha and 12x10 minutes each for RGB After full calibration with 24 darks and 50 flats/50darks the processing consisted of:- Levels Curves Gradient removal Contrast curves Ha added as a luminance layer at 50% opacity Colour balance Further contrast curves No sharpening or noise reduction/smoothing was used One thing I have really noticed so far is how noise free this camera is The Ha version can be seen on the 'Nebulae 2' page of my website Imaging The Heavens - Home Page and a full size high resolution version of the final result can be seen at the following link IC59-53 in HaRGB photo - Gordon Haynes photos at pbase.com Thanks for looking Best wishes Gordon
  4. Hi Peter You are absolutely spot on, at the end of the day you get what you pay for and yes, FLI do appear to be more expensive although some of the offerings from Apogee and SBIG can work out more expensive in the long run eg buying a new filter wheel and new filters for the SBIG16803 as 2" filters won't work because of the in camera guiding chip. In my opinion FLI offer the best facilities, build and performance for the money Best wishes Gordon
  5. Hi Glyn Thanks for the comments, regarding my criteria for choosing the FLI here goes 1. Faster downloads than other similar chipped cameras which is essential when taking sky flats (try doing successful sky flats when the download time is in excess of 20 seconds) 2. Deepest cooling at -60c below ambient (mine will probably go -5c below that courtesy of a mod), other cameras may only go as low as -40c below ambient and every 5-6c reduction in cooling equates to half the noise 3. Speed in reaching specified temperature of 5 minutes and less compared to over 40 minutes with some cameras means more valuable imaging time 4. Stability of temperature once it gets there. I spent 18 hours continuous indoors taking dark frames at 5, 10 and 30 minutes with the camera set at -35c (-54c below ambient) with the cooler power at just less than 90% and the temperature never wavered. I have heard of issues with other cameras at keeping the desired temperature stable 5. RBI annihilator as standard with all cameras, admittedly some cameras may not need it but it is there and gives a sure fire solution to the problem without having to resort to such unrealistic advice such as switching the camera off and waiting for an hour before switching it on again (and then wait over 40 minutes for it to reach temperature, how realistic is that), using RBI annihilator can add up to 30 seconds to each image with the flooding and flushing, for me that amounts to about 10 to 20 minutes in a typical nights imaging. 6. External shutter which is user serviceable if need be, I know SX puts the shutter inside the sensor chamber, personally I'm not keen on the idea as any risk of a contaminant could ruin the sensor 7. Bomb proof construction with hermetically sealed chamber purged with an inert gas to prevent fogging 8. Choice of not having a cover slip on the chip (makes the camera slightly more sensitive and further reduces risk of haloes and reflections) 9. Customisable chip height 10. Choice of shutter 11. Choice of optical window 12. Lastly, I met up with Gregory Terrance and Jim Moronski from FLI at NEAF in New York last year and discussed my needs with them, not once did they try and sell me a product (quite frankly they didn't need to as the product speaks for itself), instead they advised that when I was ready to think about upgrading to ring them and they would discuss all available options to get the best out of the camera and equipment Best wishes Gordon
  6. Hi I got my new ML8300 a couple of weeks ago but as usual the purchase of new astronomical equipment seemed to coincide with a sudden and prolongued increase in cloudy weather (I'm thinking of calling this "Haynes Law"). Anyway, I managed to get out on Sunday night and do 4 hours of data on IC59 in 30 minute sub frames before thin cloud interupted the session just after I did a meridian flip. It was taken with my FSQ106ED at f5 on a Paramount ME with autoguiding done by a Lodestar and OAG using dithering with a 5nm Ha filter. I was also committing the terrible sin of trying out new software as well as I have upgraded my Maxim DL to version 5 and Photoshop to CS5. I have to admit, that although Maxim DL v5 is a better program and more up to date, I don't care much for the user interface and found the old one much easier to use. That being said everything went without a hitch. I shot all the dark frames the previous week indoors with the camera cooled to -35c which it had no problem doing (less than 5 minutes to cool) All the dark frames and light frames were shot with RBI annihilator set to 2 seconds/2 flushes. The flats and corresponding darks had no RBI tool used. The processing was fairly simple as it only involved levels and curves ( several iterations of 'S' shaped contrast curves)and some selective contrast adjustments, no sharpening, gradient removal or noise reduction was used. The ML8300 that I purchased from FLI has no cover slip which slightly increases the sensitivity and also helps reduce reflections further This is the first time I have imaged this nebula properly and it is dim, I may add some RGB to it later as it doesn't respond very well to OIII and SII as far as I am aware. There is a full size high resolution version at the following link IC59 photo - Gordon Haynes photos at pbase.com Thanks for looking Best wishes Gordon
  7. I will be there from Friday afternoon and helping out on the Widescreen stand so come over and say hello. Hopefully I will get time to come around the fields in the evening armed with my Nagler 31mm and Ethos 13mm (the only time I get to use them) Best wishes Gordon
  8. Hi I was looking out of the office window at work at about 6.20am and saw this, I am used to seeing red skies in the evening and morning but I haven't seen a golden sky. I rushed out with my trusty Blackberry Torch mobile phone and took this, the sun still behind the houses was illuminating the clouds from below. Five minutes later the effect was gone. This is as it came straight from the camera. Best wishes Gordon
  9. Hi guys Thanks for the comments, I think the redness is caused by the amount of stars which have a red colour and corresponding halos that give the image this effect. When i zoom in on the background on my monitor I don't notice any redness so I assume it is because of this, when i have looked at other images the stars have either been suppressed more or the exposures have been shorter so this hasn't been so evident, as i pushed the processing further to bring the dusty regions out more stars popped out of the darkness so to speak Best wishes Gordon
  10. Hi I had previously posted an image of IC5146 with red and blue channels and the green synthesized from the red an blue. Ihave finally managed to get the green data so here is the final result. It is a total of 4 hours of data per channel in 10 minute sub frames taken with an FSQ106ED at f5, Starlight Xpress SXVF H9 on a Paramount ME with auto guiding taken care of by a Lodestar and OAG. All raw frames were fully calibrated and stacked, then colour combined in Maxim DL with G2V star calibration. Processing was two iterations of levels followed by multiple contrast curves, this was followed by two iterations of shadows/highlights to bring out some of the fainter dusty areas. Final colour balancing was done and gradients were taken care of with gradient xterminator. The synthesized green channel version can be seen on the front page of my website Imaging The Heavens - Home Page with this one for comparison and a full size high resolution version can be seen at the following link IC5146 - Cocoon Nebula RGB photo - Gordon Haynes photos at pbase.com Thanks for looking Best wishes Gordon
  11. Hi Dave Excellent capture, I won't repeat the comments that have already been mentioned about the stars, but I have a comment based on when i took an image of this and that is the very bright central part of the bubble, this bit has a nice bit of detail and may be worth selecting this with the lasso tool, feathering and inverting the selection so that when you stretch the image this area is held back, it will have to be done earlier in the processing but it will give another dimension to the bubble Best wishes Gordon
  12. Hi Francis Regarding the noise, I'm afraid there is only one solution and that is to shoot more data to get a better signal to noise ratio, I used 4 hours in ten minute subs and I found I could use the shadows highlights tool twice without introducing any noise in the image. Unfortunately there is no short cut to this, you just need to get more data in order to use this facility Best wishes Gordon
  13. Hi Francis That is looking very good, I have a suggestion that you might like to try if you have photo shop and that is just to back off slightly on the nebula so it isn't quite so bright and then use shadows/highlights adjustment to see if you have caught some of the surrounding dust that surrounds the nebula, this adjustment works very well at this Best wishes Gordon
  14. Hi Thanks for the comments everyone, following some of the comments I decided to reprocess the data and this is what I came up with, the stars are more evident which is to be expected of this region and I have adjusted the colour balance as the nebula was a bit too orange. I still plan on doing the green data when time and weather allows. Here is a link to the full size version IC5146 - Cocoon Nebula (reprocessed) photo - Gordon Haynes photos at pbase.com Best wishes Gordon
  15. Hi As the moon wasn't rising till late and it was in crescent phase I thought I would have a go at some RGB imaging and I decided on the Cocoon nebula which I have had a couple of goes at in the past. I shot the red data on Saturday and got 4 hours in 10 minute sub frames and just over 4 hours for blue last night again with 10 minute subs. With the light pollution where I live this really was pushing it to the limit but I thiunk the results were worth it. I decded to experiment a bit so I created a synthetic green channel from the red and blue data, this was also partly due to the chance of the weather not playing ball for the next few nights. After creating the synthetic green channel I followed my usual processing work flow of a couple of iterations of levels followed by several contrast 'S' curves, during this process I "inverse selected" the bright stars so they wouldn't become to bloated and dominant. I then did some colour balancing using Selective colour and a couple of iterations of shadows/highlights to help bring out some of the dust and urrounding nebula. I will still try and get some green data later this week but I was quite pleased with the result so far. This was taken with the FSQ106ED and Starlight Xpress SXVF H9 on a Paramount ME. Just to give an idea of the light pollution where I live, my house is surrounded by other houses and streets on all sides, all my neighbours have bedroom lights which for some reason seem to be on all night, two of the neighbours have security lights which come on frequently during the night. There is an outdoor tennis court a couple of hundred yards down the road with flood lights that stay on till past midnight. There is also a street light 30 yards away that shines into my garden. Please don't get me wrong, I'm not trying to make excuses but I think it is possible to do RGB imaging from light polluted sites if you are prepared to work around it, hopefully this image will reinforce that. Earlier attempts at this subject can be seen in the image gallery of my website Imaging The Heavens - Home Page There is also a full size version at the following link IC5146- Cocoon Nebula photo - Gordon Haynes photos at pbase.com Thanks for looking Best wishes Gordon
  16. Hi I agree on all of the above, if you want to improve then you need "constructive feedback" (a better term than criticism). While it is nice to receive praise from your peers about your images it doesn't tell you if there is anything amiss and therefore you don't learn anything. I have to say that the improvements that I have made in my imaging/processing have been from the constructive feedback that I have received in various forums and groups. One of the people that I always eagerly await feedback from is a good friend of mine Richard Crisp (especially in relation to narrow band) because he has often been able to suggest little tweaks that make an image really pop and turn a very good image into a fantastic one. Sometimes we miss these things and need somebody else to look at it. It is important to remember, however, that you will only improve if you take on board the feedback and try it Best wishes Gordon
  17. Hi This is a good thread with plenty of good advice for what is actually a difficult question to answer, let me explain "How do you like your eggs?"----Fried, boiled, poached, boiled (soft or hard), scrambled, coddled, baked, pickled, etc. This may seem a bit daft but I see astro imaging and processing in the same way, ie there is more than one way to process an image depending on the result you want to achieve, your skills, the type of imaging that you are doing and so forth. Personally I think the best way to learn is through forums such as this. From a personal point of view I think videos teach you how to process according to someone else's methods, so if you get the Adam Block videos you will process your images in the same way is he does rather than develop skills and techniques of your own, there is nothing wrong with this but are you actually learning anything? All the techniques that I use in my imaging and processing workflow have been learned through a combination of trial and error, following tips and advice on forums and discussion with people who have a lot of experience in particular fields eg Richard Crisp in the case of narrow band imaging. For what it is worth here is my work flow in brief from acquisition to end result 1. Select subject 2. Focus, focus, focus and focus (needs to be checked during the night especially with temperature changes) 3. Frame the subject 4. Calibrate auto guider and start tracking using dithering between each exposure 5. Set exposure time (30 minutes per frame) 6. Start imaging 7. I do one filter per night 8. Repeat the same process for subsequent filters, I use cross hairs on the screen to get the framing right each night 9. This is all done with Maxim DL, the telescope is controlled by The Sky 6 10. All raw frames are calibrated with darks and dark subtracted flats, I don't use bias frames as I don't scale my darks, the flat frames are taken with an electro-luminescent panel 11. The calibrated sub frames are then stacked and use sigma reject in maxim to do this using auto star matching to align the frames 12. I then align and colour combine the three master frames in Maxim DL, the reason I do this is because I do most of my imaging in narrow band and I find that the weighting compensation in Maxim easy to use and I can see what effect it is having on the colour instantly. 13. I then stretch the image using a gamma stretch with a value of 0.1 and maximum pixel value, this ensures that none of the information is lost and the gamma stretch gives the best overall results especially for nebula 14. I then save this as a 16 bit tiff file using a linear screen stretch so that when I open it in photoshop it appears exactly the same as where I left it in Maxim DL 15. When I open it in photo shop the processing is surprisingly simple 16. I start with some desaturation of the magenta which is only present in the stars as a result of boosting the OIII and SII channels, a couple of iterations of levels using only the mid range slider and adjusting the black point after each iteration. 17. This is followed by several (anything up to 10) iterations of mild 'S' shaped curves (this brings out more detail by increasing the contrast) 18. If the brighter stars start to become bloated I use the colour select tool to select the brighter stars and increase the selection by 2 pixels and then feather by 2 pixels and then invert the selection, this has the effect of selecting everything apart from the brighter stars, this allows me to concentrate on the nebula without worrying about over bloating the stars 19. When I have got the nebula appearing as I want it I generally do a final colour balancing to ensure the histograms are roughly the same and in order to tone down the sometimes garish colours associated with narrow band imaging I use selective colour to shift the balance to the generally more acceptable appearance of the Hubble palette 20. If there are any stacking artefacts on the edges I will crop the image and the final thing I do is to use the clone stamp tool to get rid of any hot pixels or gamma ray streaks 21. Finally I use the save for web function to save as a jpeg for my website and posting This may look daunting but in reality it takes me a maximum of about 3 hours from calibrating to the end image. You will notice that I don't use masks, sharpening, noise reduction, RGB star layers, etc. Although I have Noel Carboni's tools for photoshop I no longer use them as I have found that getting good data gives the best results and makes the processing easier. I find that if the data is sufficient and good quality then you don't need it. Also when I used sharpening and noise reduction in the past it left visible artefacts in the image. I use layers but purely to check each stage of the processing. This is my way for doing narrow band images, other people will have different methods Best wishes Gordon I forgot to mention and I think it was mentioned elsewhere, you need as many sub frames for each filter as possible, typically I aim to get between 9 and 12 sub frames of 30 minutes each, occasionally I will go as low as 6 but at least that is still giving me 3 hours per filter. As far as the calibration frames are concerned the same applies
  18. Hi I had previously taken some Ha and OIII data on this and managed to get out and get 3 hours of SII data in 30 minute sub frames. Normally I process my narrow band images using the HST palette partly because I prefer it but also because it is more scientifically correct in that the filters are asigned in order of wavelength, but I found that using this palette the OIII envelope that surrounds the main nebula didn't show up very well so I changed to a palette commonly used by the Canada France Hawaii Telescope (CFHT) where the filters are asigned to RGB in the order of Ha:OIII:SII. This was taken with my current set up of Takahashi FSQ106ED at f5, Paramount ME and Starlight Xpress SXVF H9 with exposures of 7x30 minutes for Ha, 8x30 minutes for OIII and 6x30 minutes for SII, I would have got more SII but clouds interrupted the session. The master frames were colour combined in Maxim DL with a weighting of 1:2:7 for Ha:OIII:SII and processed in Photoshop CS2 using levels and a series of 'S' shaped contrast curves, in order to better distinguish between the main nebula and OIII envelope I used selected colour to shift the colour balance. All three versions (Ha, Ha/OIII and CFHT palette) can be seen on the Nebulae 2 page of the image gallery of my website Imaging The Heavens - Home Page and there is a full size image at the following link NGC6888 - Crescent Nebula in CFHT palette photo - Gordon Haynes photos at pbase.com Thanks for looking Best wishes and clear skies Gordon
  19. Hi Olly I might have a go at that one next Best wishes Gordon
  20. Hi This is another start of a tri-colour narrow band image, this time it is NGC6888 and so far I have managed to get 7x30 minutes of Ha data with the FSQ106ED at f5, Starlight Xpress SXVF H9 on a Paramount ME auto guided by a Lodestar and OAG using dithering. This combination gives a nice field of view to give the nebula a bit of context with its surroundings. Again the processing has been fairly simple with just levels and curves being used. I have tried this subject numerous times before both in monochrome and colour with a variety of scopes and camera combinations. These earlier images can be seen on my website Imaging The Heavens - Home Page I will be adding some OIII and SII as soon as the clouds clear again. A full size image can be seen at the following link NGC6888 - Crescent Nebula in Ha photo - Gordon Haynes photos at pbase.com Thanks for looking Best wishes Gordon
  21. Hi I have been making the most of the clear nights recently to get some imaging time in. This is one subject that I have never tried before but it is a very nice target to do in Cygnus and responds well to narrow band if you are prepared to put the time into it, it is quite a faint subject which is probably why it tends to be ignored as an imaging target. This was taken over three nights and is 6x30 minutes per channel using 5nm Ha, OIII and SII filters. I used the FSQ106ED at f5 with a Starlight Xpress SXVF H9 on a Paramount ME. Auto guiding was taken care of by a Lodestar and OAG using dithering. The raw frames were callibrated and stacked and colour combined in Maxim DL using a weighting factor of 5:1:7 for SII:Ha:OIII (the OIII was particularly weak for this subject), after doing a gamma stretch with a 0.1 value and saving to 16 bit tiff it was transferred to photoshop where a couple of iterations of curves was used followed by several minor 'S' shaped curves. I will probably add some more data at a later date A full size image can be found at the following link Sh2-101 Tulip Nebula in HST palette photo - Gordon Haynes photos at pbase.com Thanks for looking Best wishes Gordon
  22. Hi Tim Thanks for the comments, this is my favourite time of year, from May to March as the sky is full of emission nebula during that time Best wishes Gordon
  23. Hi I am off work on annual leave for a couple of weeks or so and it makes a change to have some clear skies to coincide with that even though the hours of darkness are a bit short. This is a narrow band image of NGC7380 in Cepheus which doesn't seem to be a very popular target for some reason. This is the first time I have imaged this in full colour, I had previously done it in Ha with the BRC-250 a couple of years ago. This can be seen on my website Imaging The Heavens - Home Page It was taken over three nights and is 8x30 minutes each for Ha, OIII and SII which were then mapped to the wavelength ordered palette used by Hubble. It was taken with a FSQ106ED at f5 and Starlight Xpress SXVF H9 on a Paramount ME, auto guiding was by a Lodestar and OAG using dithering. Processing was levels, curves and colour balancing A full size cersion can be found at the following link NGC7380 - Wizard Nebula in HST palette photo - Gordon Haynes photos at pbase.com Thanks for looking Best wishes Gordon
  24. I agree with what others are saying about the image, it is very nice and detailed. From the noise and noise reduction issues, it does look over smoothed and as a result some of the definition in the surrounding nebulous cloud is lost. In order to avoid these issues it is best to avoid any form of noise reduction as it does have adverse effects on the overall image. In order to reduce the possibility of noise creeping into your images you need to shoot more data pure and simple, there is no other way around it. With narrow band imaging you are typically looking at a minimum of 4-5 hours data per filter for an f5 system (more if the system is slower). Also I would recommend that unless you have a super fast system of faster than f5 then your minimum length of exposure should be 20 minutes as this will give a better signal to noise ratio which will help keep the noise down. Finally make sure your raw frames are properly callibrated. I use an f5 system and I do 30 minute exposures with a minimum of 4 hours per filter and I don't use any form of noise reduction in my processing. From a personal point of view I feel that the use of noise reduction is a short cut for not having enough data in the first place Best wishes Gordon
  25. Hi I had already shot some Ha and OIII data over the past couple of nights with the Starlight Xpress SXVF H9 camera and I was hoping for some more clear weather but the clouds have come back in and then I am working for 4 nights so it will be at least until next week before I can shoot some SII. A good friend of mine Richard Crisp suggested it might be fun to try combining the SII data that I took with the Starlight Xpress SXVF H36 camera last year for a widefield shot of this region so I thought I'd give it a go and see what came out. This is the first time I've done this and I did it by cropping out a section of the widefield master frame for the SII and then aligned it with the Ha and OIII frames taken with the H9, this was done with Maxim DL. I then colour combined in Maxim DL with a weighting of 10:1:7 for SII:Ha:OIII, this may seem extreme but this was required to give equal signal and for the histograms to be roughly the same as each other. One iteration of levels was used followed by several minor 'S' shaped curves adjustments, with a final colour balancing and saturation reduction for the stars which understandably were a bit magentaish. Just as a reminder for the details Takahashi FSQ106Ed at f5 Paramount ME 9x30 minutes each for Ha and OIII with a Starlight Xpress SXVF H9 (1.4 megapixel with 6.45uM pixels) 8x30 minutes SII with a Starlight Xpress SXVF H36 (16 megapixel with 7.4uM pixels) Although the image is a bit noisy I am quite pleased with the result, I will still shoot some SII data with the H9 when I get the chance to see if it will improve things. Again I have used no sharpening or noise reduction in the processing. All three versions of this are now on the home page of my website Imaging The Heavens - Home Page for comparison Thanks for looking Best wishes Gordon
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