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Darth Takahashi

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Everything posted by Darth Takahashi

  1. Wow, that's a fantastic image and only 15x3min sub's. Whats the focal ratio of your telescope? How fast is it! Neil.
  2. That's a very good first attempt at Saturn, well done. Neil.
  3. Wow you're just too critical, both are nice images... if you want perfection you probably need to move location... I hear Chile is nice and dry with very little atmospheric water ;-) Neil.
  4. Very nice capture, still a little noise in the red channel, try tweaking it in PS. However, nice resolution & detail. Neil.
  5. This is a tricky subject and by no means simple. The mathematics tell you only part of the story, the rest is down to the equipment used to gather the data. I used to try and take long subs and a minimum of 4/5 darks and bias frames, no flats. Now I just take as many shorter subs as I can with no calibration frames at all. Since the noise should average out over the greater number of sub's. This is all under the following assumptions; 1. You are imaging with an uncooled camera, such as a DSLR 2. That noise remains reasonably controlled in the shorter sub's 3. The subs are in the range of 3 - 5mins @ ISO400/800 Is seems that the noise in a DSLR spreads as a function of time. This is my take on this subject. Neil.
  6. TJ, Unfortunately I cant make the SGL4, I will try next year. Can post a CD with the RAW and stacks, no problem just PM me with the details etc... I will be in the UK from the 25th April but have family commitments in Warrington. Neil
  7. I wasn't doing anything special with DSS and I was using RAW or CR2 from my Canon Kiss 2X (450D). I selected sigma kappa = 2 and 3 iterations etc... DSS would get to the final step of stacking the images and fail with the out of memory error! All the CLS filtered images received relatively low scores compared with the unfiltered images. I did try removing the colour cast / reducing it by editing the RAW's this did improve the score. However, I can't rule out the fact that I might have also slightly stretch the images? It took 3 days on and off to stack the final TIFF 16bit file. I do most of the final processing with PS CS4 using Rod Wodaski tips and books. I did try stacking the images with Maxim DL at one point, more out of deparation than anything else. After this weekend I can't help but see DSS as a weak point in my image processing flow. I certainly like everyone else rely on it too much. Does PixInsight stack images? I see a lot of people using it on the forum. Neil.
  8. Thanks for the generous comments. Dave regarding the black point, you are right, I have tried to find a balance between allowing a red colour cast to make its way into the final image and cutting it out using the black point. Its a shame that I cannot post the TIFF file for some of you other imaging guru's to have a go at, if you wanted to that is? Neil.
  9. That's a great image and effort, I know exactly what its like to struggle with both the moon and a sky that wouldn't quite clear. All that wispy cloud sh$% gets on my nerves:mad: Neil.
  10. I wasn't going to post this image since I don't see thats its a great improvement over the last one. Well here it is anyway. Approx 2 hours 45 minutes worth of data but too much noise still. Telescope TA130F Camera Kiss 2X (450D) @ ISO800 Subs 49 x 3 - 4mins Struggled with DSS since it wouldn't stack so many images; Lots of problems with out of memory messages etc... I have a laptop with 1.86GHz dual cores and 2GB of memory..! As far as the image is concerned, I'm sure the nearly full moon only 35 degrees away didn't help even though I used a CLS filter. In fact I'm sure the CLS filtered images gave DSS a lot of trouble. Curren'tly not sure why, putting it down to the cyan colour cast at the moment. Neil.
  11. My last comments on this subject are as follows; There are two significant purchases that you are going to make in this hobby and they are listed below in order of priority; 1. Mount 2. Telescope Where the mount is concerned things are at least clearer, since the characteristic that you want are known. High tracking accuracy with low periodic error, GOTO at least for me was an option (nice to have). Where the telescope is concerned things are not so clear at all. There are so many different option available from different company for different tasks etc... Over time I have upgraded by telescopes and mount. Although it my appear that I have spent a small fortune on this hobby, I didn't spend it all in one go! Now to the point, once you have navigated the telescope mine field and made your selection. The last thing that you want to discover is that you have selected a marginal telescope! Especially when it represents a significant part of your budget. To me the issues with the FLT132 seem to be silly, unless some optical expert want to correct me, it seems additional / slightly bigger baffles would cure this issue, correct? Therefore, WO should action this ASAP. Regarding the review, which I have yet to read, my S@N will be sent on to me soon. I agree that we need proper repeatable optical test results for such equipment, not the simple statements that are currently made. Once people have made such a purchase they will most probable keep such a telescope for a lifetime and thats what these reviewers need to understand. This is my last rant on this subject. Neil.
  12. Thanks Gaz, that is indeed the website, I'll bookmark it this time. You don't need to read German has numbers are numbers and as Gaz points out either google or babelfish make reasonable translations. The problem with telescopes is even reasonable ones can make good images of extended objects. You should never buy one based upon the images made by others as there are just too many variables!!! This guy Rohr performs repeatable scientific optical tests hat cannot be easily disputed, if at all. Neil.
  13. I guess it depends when you go... still its a small price to pay for those bueatiful images. My Family and I climbed Mt Fugi last year, during the night it was +3 and during the day +25, 3776m. For some reason the wife refused to carry my telescope up? Neil.
  14. No thats a great response Karsten, isn't there a german guy testing the hell out of all these so called top class telescopes? I keep running into a site every now and again but its in the German language so I never book mark it? Anywa,y the reason I ask is that I remember him turning up problems with WO, however the TMB designed telescopes were OK. My question is do you know this site? It always nice to have independent data to back facts up! And before anyone thinks I have a problem with WO, I have owned and passed on now a very nice Zenithstar 105. I still own several items including my favorite eyepiece UWAN 32. Neil.
  15. I think the best advise is as follows; 1. If you have a cooled camera go as long as you can with your sub's 2. If you are a patient man experiment as Peter suggests to find the optium settings. 3. If you are just a pratical man wanting to image start with 3 min subs and build up to 5min then 10mins However, be warned going over 10min's with a DSLR might not bring you what you wanted. As for the article the problem is the SPREAD of the normal distribution for the DSLR's tested. The cooled camera's maintain nice tight distributions where noise is well controlled. Obviously thermal noise is the issue and the reason that the HYPER mod's exist. Neil.
  16. Thanks for the comments, I'll try and get some more subs tonight weather permitting of course. Looks good so far, fingers crossed. Neil.
  17. Wow great images, It just goes to show how much we really are up against it here in Northern Europe. I'd love the opportunity to image under such skies... 2000+ meters and warm steady air... wonderful... Neil.
  18. The weather held so I decided to image as long as I could. For me Leo started it decent into the murk at around 02:00. My lights were getting brighter so I stop imaging and retired indoors with my kit. Telescope: TOA130F Camera: Kiss 2X (450D) Filters: None Exposure: 5x 5mins + 18x 3mins @ ISO800 I have attached a quick processed version. Will see if I can draw anymore out of it later on. Its not bad for a DSLR, I'm alittle disapointed that I haven't pickup any colour. Neil.
  19. That's an amazing image, well done, looks like the weather holding, if its does I'm going to have ago at the Leo triplet myself tonight. Neil.
  20. Very true but it does depend on where you buy? I benefit from the fact that I work in Japan for half the year and know a nice Japanese guy called Yamamoto san at Starbase, Akihabara, Tokyo. If you ever get the chance you should drop in a say hello ;-) Neil.
  21. Wow, that very nice... I think am definitely going to have to get one of those DMK21s Neil.
  22. Dennis, Fully agree with you regarding your TMB. I think the point is WO have been too greedy with the FLT132 and the tabs are obviously being picked up in the optical train. As Steve points out, baffleing would have prevented this. Perhaps then the FLT132 its really a 128mm where an extra 2mm baffling would have stopped this issue dead in its tracks. Alas we will never know! I thought the lens cell in the FLT was made by TMB? Does anyone know whether or not this is still true? Neil.
  23. Not sure how productive some of these statements have become? So serious imagers only use Takahashi telescopes! Well this statement is about as useful as claiming serious imagers don't read or rate Sky@Night reviews... I'm sure every magazine that has to make such a comment makes certain they are correct first. It's too easy just to dismiss it out of hand. Well I'm still happy, lots of nice baffles and no metal tabs to be seen Neil.
  24. This is going to get confusing, well here goes... Great images of Saturn, I'm also think of stepping up to one of these DMK series of cameras. I'm still using an SPC900 at the moment and its fast becoming the limiting factor... Where can I find the thread on the DMK21? Neil H.
  25. Good to hear you are at one again with your telescope Phil. I always wondered how so many of them end up on the equipment for sale boards. I think you have to accept them for what they are good at and to forgive them for their limitations and if you can, collect a couple for different tasks ;-) Neil
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