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lensman57

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Everything posted by lensman57

  1. Opticstar no longer has a showroom. There was one in Stockport but I think that it may have gone bust but I am not 100% sure of that. Rothervalley Optics is still in business. A.G
  2. Amazing field of view showing off the are around Afirk and Alderamin very well. Delicate processing also helps the overall feel of dustiness. Regards, A.G
  3. Thanks for that lensman I had no idea about that. I used dss and ps to ruin it. Any idea what the right way is? Hi Matt, Since you asked for it I will try and explain and hopefully it makes sense. When you use an OSC sensor to gather Ha data you are only allowing a very narrow wave band to get through to the sensor which can only be picked up by the Red sites on your sensor. This however does not mean that the two Green and one Blue sites are made redundant quite the reverse as all the sites are charged up and only the Red site is gathering data the other two are just pumping idle state noise into your data stream. This green and blue noise must be prevented from getting mixed up in your final stack. There are ways to do this depending on which software you are using . I use Pixinsight so it is slightly different way of doing things but as I remember DSS can do it too. The trick is to allow the software to calibrate and debayer the data but separate the R,G,B components. You will then delete the G and B data which is nothing but noise and then register and integrate the R which is now pure Ha data which is Monochrome BTW and you can colourize it to your hearts desire. This way you will still end up with some noise but it is nowhere as prominent as just throwing everything in to the pot as they say. Let me know if you need further assistance. Regards, A.G
  4. How did you process the data from the sensor if you don't mind me asking? There is a correct way of doing this and any other way will just give you noise. What was the processing software? A.G
  5. Glad that you have sorted the issues out. As matter of interest I never trust the error figures that PA aligning software gives. In the first image the rotation is indicative of errors well above one degree of arc given the short focal length of the scope. None the less a few iterations of the PA routine always bring the error down to an acceptable level as you have discovered. Regards, A.G
  6. Achros are a waste of time as far as imaging is concerned, forget about them. There are good ones but these have very long FL with F11~F15 and are mostly for lunar or planetary observing. As for the imaging scope please forget the aperture business, that is only relevant for observing. In theory a larger aperture will offer higher resolution but here in the UK with our weather, light pollution and less than ideal seeing at the best of times no real benefit will be had from a high res system such as a TAK Epsilon but for shorter integration times. A good ED need not cost the earth SW 80 ED is a very well corrected ED doublet and can give some expensive triplets a run for their money. It is relatively slow but not by much and a reducer will give you a wider FOV. The focuser is nothing to write home about but with a bit of care and adjustment and so long as a huge CCD and FW is not hung from its back side it will function. You will also have change left from £500.00 to do other things with. Regards, A.G
  7. Well you can not possibly do DSO imaging using binoculars or at least not the ones that are affordable to us mortals. For exploring the night sky there is nothing like a binocular but it has to be a good one. It can not be too heavy as to need some sort of contraption to keep it steady. You would want as large an exit pupil as possible to enhance the vision and the light gathering must be good. In the old times ( a very long time ago ) I was always after a 8 x 56 but these are a very pricy these days. A more reasonable offering is the Nikon Aculon 7 x 50. I have a Strathspey 15 X 70 which is good but very heavy and bulky. As for the telescopes I am afraid that you get what you pay for. An ED doublet is an absolute minimum and Achros will not do for proper imaging. Besides the CA these budget scopes suffer from a multitude of optical aberrations . Get yourself a decent Wide Field ED to start with. A.G
  8. M31 has a very bright core but the outer reaches are extremely faint so while observing through a small aperture scope all you see is a fuzzy blob which is the core. Using high power EP is actually counter productive as it narrows the FOV to the centre of the core. Use a high quality WF EP and use averted vision to try and see the extent of the galaxy. For reference M31 has an angular diameter 9 times the size of the full Moon so it is a colossal object in deep sky. You will also not see much if any colour at all as our vision is geared towards detail and movement and we are weak in colour. A.G
  9. That would help. You also have some cut off at the lower left and to a lesser extent the upper left. Have you cropped the image? If so you need to correct this with flats. If not then make sure that the FW is indexing the filters central to the optical axis . A.G
  10. This is a sensor problem. If you could post a link to the original single Bias, stacked Bias and Darks this could be verified. Next time try and image at a much lower ISO setting and see if it makes a difference. A.G
  11. This is a good start. You actually have more data there that needs pulling out. The core is blown but as you know you need a set of very short subexposures to control the core. Regards, A.G
  12. Hi to all and thanks for your comments. I have to make an apology as to the data stated 18 X 900s, it should have been 18 X 600s. Regards, A.G
  13. I have revised the processing of the data from 01/10/15. Hope you like it. WO Star 71, Modified Canon 1100d, Astronomik CLS Clip filter. 18 X 900s + 13 X 120s. Processed in PI and PS. Regards, A.G
  14. This is excellent particularly for an unmodded camera. Lack of severe light pollution is evident. I have taken the liberty of trying to colour balance and increase the saturation in the Yellow/Red channel without making it too noisy in PS but working from a copy of a jpeg is not ideal . Your RED channel was also heavily clipped . Hope you approve. Kind Regards, A.G
  15. This has the makings of a brilliant image but I also echo Sarah's points. If noise reduction was applied I would turn it down a tad. Olly once advised me not to be frightened to show a bit of grain in space. Amazing capture none the less. Regards, A.G
  16. Good stuff is always timeless. A.G
  17. This is amazing Martin. Last year I foolishly tried it with 900s subs and got nothing but blackness. You have inspired me now to try again with more realistic sub lengths. Regards, A.G
  18. Well done. The first one is always special and it will get better from here on. SGL does not allow you to upload TIFF as far as I know so upload either jpeg or better still small size PNG files. If too large then SGL will apply compression to your file before displaying it. Regards, A.G
  19. Hi to all, I have not been doing any imaging for quite a while. Bad health and job related problems. This data was gathered on the night of 1st Oct and was just sitting around on the hard disk. I was not going to process it but since I do not have anything else to show I went ahead and processed the data today starting at 2pm. Man it is easy to forget everything even after a couple of months. The image is an HDR combine of 18 X 600s and 13 X 120s with the appropriate calibration frames applied. The 120s data has had minimal processing as it was only meant to protect the core but the processing of the combined data before revealing the core has been extensive. There is a little tilt to the plane of the sensor showing in the far left stars but it is not too bad and I need to correct the rotator for this when I get my enthusiasm up. 18 X 600s + 13 X 120s , Ditthered data at max value in APT. Modded Canon 1100d, Astronomik Clip Filter, WO Star 71, HEQ5 Pro. Stacked and processed in PI and tweaked in PS. Thanks for looking, Kind Regards, A.G
  20. Putting two grub screws on top of each other is an old engineering trick to secure the component with grub screw without resorting to a permanent bond such as Loctite. It is also a warning that the part is crucial to the function of the apparatus and not to be messed with. Whether this practice is justified here is another matter. Telescopes should be designed to be serviced easily and be put together back and be adjustable, at least the good ones are so. Regards, A.G
  21. It is called a Black Hole because it has such immense gravitational pull that even light photons can not escape its gravity. I doubt if you could image it in conventional terms and you need to look for its effects. Gravitational lensing is one of them .Black nebulae or dust lanes are immense structures in their own right . You can draw your own conclusions. Regards, A.G
  22. Lovely image Chris. Shame about the airline light trail. A.G
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