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lensman57

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Everything posted by lensman57

  1. The best thing you can ever do is the one that improves your imaging but doesn't cost money. In my eyes the degree of " bestness " exponentially decreases as the cost of the item goes up. I have also read the posts stating that the " best thing " some one ever did was to spend £5000.00 on a mount or £4000.00 on an all singing and dancing CCD camera and these do not really impress me. The best thing that you can probably have is a piece of sound advice and these are usually free if a bit hard to come by. Regards, A.G
  2. Hi, I am aware of the AZEQ5 having encoders but TBH I have not heard of any great achievements in guiding performance even from the users of AZEQ6 though I have to say that I think theAZEQ6 is the star of the SW mount line up particularly now that the price has come down quite a bit. HEQ5 takes as little as 10 minutes to set up for observing or imaging if you mark the position of the legs from a previous session and start the mount from the parked position the 10 minutes includes at least one cycle of the Polar align routine using a 3 star alignment. As I said in my previous post if money is not an issue than go for the best mount that you can afford regardless of whether you have any use for the extra capacity now or not. A.G
  3. There is no colour information in the processed image. If possible put the subs and the calibration frames in drop box and post a link and we see what can be done. A.G PS: I am not sure if QH8L and QHY8 have the same Bayer Pattern but for my QHY8 I use RGGB in Pixinsight.
  4. HEQ5 is fine up to 12Kg for imaging if not more. Unfortunately like many other parameters in AP this max imaging weight is a rather confusing and arbitrary measure. What affects the imaging performance of a mount excluding such factors like PE and the accuracy of the driver board to run the stepper motor is the inertia of the imaging gear. A small but well built mount will probably be fine with a very heavy but compact scope but would not handle a much lighter but elongated and " untidy " design of a scope. Most Newts once all the imaging gear are mounted on are very untidy scopes so you would need a larger mount that could cope with the inertia of moving the set up during guiding. An 8" SCT or an Apo such the one you have in mind are easy meat for an HEQ5. I have no experience of AZEQ5 and for that matter unless SW wanted to fill a £250.00 gap to AZEQ6 I really do not see the reason for this mount being there. It is neither cheap nor has any particular attractive point that is not already presented in the SW line up. It is the same price of a new NEQ6 and more than £100.00 more expensive than an NEQ6 Syntrek ( this one can have GoTo using the Ascom platform and a planetarium software ) and £150.00 more than an HEQ5 Pro. If funds are not a problem I would go for NEQ6. As far as a DSLR and a 200mm lens is concerned large summer nebulae are its main targets the downside of this theory is that with UK latitude and the very short summer nights a lot of imaging needs to be done over a few clear nights and that is at a premium in the UK at least where I am. Right now the true " astronomical dark " period is just over hour or so for my latitude. A.G
  5. You have to decide what it is you want to image in the first place before choosing a lens. If you do a lot of terrestrial photography then buying a few L lenses or an L zoom lens might be justified provided that you could afford them but if you just want a lens for AP then believe it or not it is cheaper to get an ED scope . There is an imager on SGL who uses L lenses for DSO imaging and his images are rather brilliant but the cost of one of his prime L lenses is about £5000.00 if bought new these days but he also travels a lot and he told me that he bought the that particular lens second hand. I do have a 200 F2.8 L lens that I use for super wide field DSO imaging using either a modded DSLR or a cooled CCD but the target choices for this lens are limited. The ordinary zoom lenses will not do due to excessive CA and other aberrations. In AP the slightest flaw of the lens or the scope is immediately shown up so the quality of the optics is paramount. As far as the zoom lenses go I have 70-200 F4 L USM that I have not used it for DSO imaging but having researched the images taken by it on other forums it seems to be a good performer even for AP, this lens can be found used for about £500.00~£600.00 if they come up for sale. A.G
  6. You can use Photoshop and it goes a long way for processing the final stack. I use Pixinsight and Startools and tweak in PS. StarTools is very affordable, it has the easiest and very effective Deconvolution, Noise reduction and HDR tools but I am not too keen on the Wipe module to remove gradients, it is not the software but my impatience. It takes a little getting used to but it is just a processing software and you need to use DSS or something else to stack the subs. Pixinsight is quite expensive in comparison but the DBE tool alone justifies the cost plus the fact that it can do all the calibration and stacking of the subs. The caveat is that you have to be a mathematician to under stand all the parameters and tools but on the other hand if I can work with it anyone can. There is also Astroart but I do not use this software. Astroart has a very effective and superfast stacking algorithm and some very effective and useful filters and tools. I particularly like the filter that corrects the shape of the elongated stars, cheating for sure but useful. A.G
  7. You are too kind. They were all taken from my 25x18 feet back garden with the living room lights constantly shining thanks to my dear wife and Master Chef and all that. I am afraid that in my exuberance to accumulate CCDs I have rather overdone it but I do rate all four of them highly specially the 383L+. Shame about the person who operates them. HEQ5 is rather more portable than NEQ6 but to be honest had it not been for my deteriorating back pain condition I would have got the NEQ6. Not so long a go I was given a Celestron 9.25 " XLT by a friend of mine who was getting rid of a lot of his stuff and I am sure that it would live happier on an NEQ6 rather than HEQ5 but we can't have it all. Regards, A.G PS: It just about copes with my Quattro 8s and the imaging gear but it is right at the limit. Once the balance is sorted the guiding is fine but slightest disturbance and the sub is ruined. This is probably more a limitation of the Quattro with the puny vixen dovetail than the mount and a Losemandy style platform would have been a better choice if more expensive.
  8. Hi, I think that I am well qualified to answer your query. I live in the south Manchester area about 8 miles from the city centre, 20 yards from a well lit dual carriage way and next to a doctor's surgery with ample security lights. Manchester airport is less than 3 miles due west of my location. As LP goes it can't get worst than this. I manage to image from time to time with the help of an IDAS LP or a Baader UHC nebula filter. I have spent far too much money on this hobby already. You can have a look at my images at the link at the bottom of my post. It is certainly possible to image but in my case even with the use of expensive LP and NB filters my images are noisy, very noisy in fact even when I do manage to get a large number of subs of reasonable length. My honest advice is that unless you are able to pack the gear up and find a decent dark location spending a huge amount of money is not prudent. After all this I still have the wonderful Manchester weather to contend with and those in the know will tell you that your sky quality plays a major role in the quality of your imaging. Hope that I have not put you off this rewarding hobby but what have told you is from personal experience. Regards, A.G
  9. With the exception of the Canon none of the cameras you listed are suitable for DSO imaging nor is your mount. Spend £450~£500.00 on a used HEQ5 Pro and get the 450 modded. Summer imaging is mostly about large nebulae that are rich in Ha which an unmodded camera will not pick up. Canon has a large sensor compared to the tiny sensor of your stated cameras and will give you a decent FOV for imaging if not the most sensitive. A.G
  10. This is a very tough target even for experienced imagers with sensitive equipment and even tougher to process properly as the bright blue nebula is surrounded by very dark cosmic dust. The other prerequisite for successfully imaging this reflection nebula is dark skies otherwise huge effort is required to correct for the gradients. Your effort is good but the only way to get anything out of your set up is to collect more data. With a DSLR I would suggest a minimum of 25~30 subs of 600s each with a proper LP filter in place ( a nebula filter will do but requires longer exposure ) and the application of full calibration frames including a large number of Bias and Flat frames. You also need to have a look at the collimation of your scope and perhaps the use of a coma corrector as the star at the bottom left shows typical signs of coma. Properly imaged and with enough data you will have the outer halo of the nebula in blue and some yellow orange colour in the core (the core is made up of multiple stars at least visually ) and there is also a hint of colour in the surrounding dark nebula. Without enough data if you push the processing the end result is just ugly noise. For the sake of clarity I dumped the data from my first attempt even though it was taken with an SW ED 80 and an Atik 428 CCD with over 3 hours of data. A.G
  11. Remarkable level of fine detail in this mosaic. A very fine image indeed. A.G
  12. Thanks Guy, much appreciated. The SW100ED is a hell of a scope for the price though a bit slow. A.G
  13. Nice one Louise, I am glad you managed some imaging. It seems that imaging conditions for us up north is at a premium this year. Regards, A.G
  14. Thanks Michael, this is indeed one of the most stunning objects in the night sky. A.G
  15. This is very nice but the bottom of the image is not part of the pelican, it is called IC5068. Very good job none the less. Regards, A.G
  16. Hi, Taken early on tonight before it clouded over again. I could only manage 11 X 900s subs but only 9 were used as the clouds ruined the other two. SW 100ED @ F7.6 ( SW 0.85X FF/FR ), Atik 383L+ @ -20c and IDAS D1 on HEQ5. Processed mainly in PI and tweaked in PS. There is unevenness in the back ground that I failed to correct due to the proximity of the strong Moon. I have also attached a crop of the galaxy itself without size reduction in my software but I am sure that SGL will apply the usual compression. Thanks for looking. A.G
  17. I have not named them as recently there have been a couple of posts in the forum and I did not want to cause offence. But calling a galaxy a Spanish dancer or something like Kentucky fried chicken is a little odd and probably inappropriate. I remember a very long time ago the Jubilation of the late Sir Patrick Moore's tone as he thanked god that the twelve constellations were not named after the twelve apostles after a push by the church and the ancient Greek and Egyptian names held on. I can really sympathise with him. A.G
  18. " one very quick and stupid question - is that the LV Stack setting in the advanced APT settings? Seems to be on 20 by default, but should I be increasing that?" I can't remember the number for the love of god but I have set it as high as it gets. Regards, A.G
  19. Two weeks without a clear night? I have not seen a clear night here in the last 5 weeks. A.G
  20. Hi, I don't know how you feel about this but I detest some of the names given to these magnificent objects in the sky. Some of the nicknames are acceptable and some even endearing but others I find demeaning. I wonder how you feel about this. Regards, A.G
  21. The FWHM you get in a focus assist tool has little to do with the FWHM calculated by DSS or other stacking software . For a start APT uses the live view image to calculate the FWHM but here the exposure is very short indeed but your subs have exposures in minutes not millisecond. As the exposure is increased the FWHM value also increases as the light from the star is scattered more widely. I use an exposure loop of 3 seconds in Nebulosity for fine focus and this generally gives reliable results. The other problem as you mentioned is your local sky seeing and this is far from stable in most parts of the UK. There is a reason why they build the large telescopes on top the mountains as up there the atmospheric turbulence is less of a problem. I do use APT for focusing with my modded Canons and depending on the scope used I generally get values of around 2~3 for FWHM but I have increased the stack number to maximum. A.G
  22. These are awesome set of images. Something to aspire to. A.G
  23. In which case I think that you should consider the RC variety as well. More expensive for sure but I have seen quite a few of these being used very effectively for galaxy hunting. The 6" for sure has the FL that you are seeking and well within the budget though a dedicated reducer is needed to drop it down to around F6. F4 scopes are extremely demanding both in collimation and set up and have an unforgivingly short depth of focus. With my Quattro I found that the best focus achieved in the start of session after the cool down was no longer valid after an hour of imaging as the temp drops a few degrees and I was not in the mood to spend a fortune equipping the scope with a robotic focuser. My main reason for getting the Quattro ( I bought it at less than 1/2 price from a chap that couldn't use it ) was to go for very short exposure because of my severe local LP but it did not fulfil that role. A.G
  24. Neither of those will be my choice for a first imaging scope. A fast, short and wide ED or Apo will be much more user friendly and a lot more suitable for " widefield " AP either using a DSLR or a CCD. The FOV is much more suited to the large nebulae and the demand on guiding is not so great. Either of those scopes you mentioned is capable but in the hands of an experienced imager and the choice of targets that normally suits these are galaxies and planetary nebulae. I have the Quattro 8s and I am still hesitant to use it over my much slower 100 ed @ F7.6. A.G
  25. The data as outputted after stacking has a tremendous dynamic range that is well beyond the capability of even the best monitors to display, it is as you might say heavily compressed and like D4N has said if you look at the histogram the whole data is bunched up to the left. By stretching either using levels and curves in PS or other methods in the more AP specific software ( Maxim, Pixinsight, Startools etc, ) you are actually pulling the data apart so that it can be seen on the monitor. That is why it is called stretching. As you stretch the data you also stretch the noise that is in the data but unless you have a lot of good data compared to noise or in another word a high S/N ratio, Signal to Noise, what you end up with is a very noisy image. The only way to have a high S/N ratio is to image with as long a sub exposure length that is possible ( this is set up and local condition dependant ) and as many of them as you can gather. A.G
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