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syd_malicious

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Everything posted by syd_malicious

  1. Can't see for looking , they do do a permanent mount for it here. This doesn't seem the most permanent of solutions though.
  2. Just reading Cloudy Nights and this new mount was discussed from Mesu-Optics in The Netherlands. Not heard of it before but it looks very interesting. If the specs are to be believed it has +/- 2 sec of PE, can take 130kg of equipment, is portable and costs 7,500 euro. It does look like a bit of lateral thinking and as it uses the Argo Navis system should be well supported. My only gripes are that the advert says no measurable PE in one bit and then +/- 2 in another. Also it seems to be designed to be be portable though I suppose it could be made permanent. I have no experience of this mount or true engineering design so some of you may be more in a position to pass comment. Still, it's nice to see a new entry in the field and at a quite reasonable price too. Paul
  3. It's always nice to have something new but are sure that you are able to offer something really different etc that people would want? Another option would be to develop some astro related addons for photoshop (such as Gradient Xterminator) or develop something for Pixinsight (great program but a bit user unfriendly). I would be unlikely to use a new program having invested in the above but addons certainly could be attractive..............just a thought. Paul
  4. Yes and no. The basic optical design is similar but the RCX is F8 (I think) whereas the ACF is F10. Also the RCX has a lot of electronics on the tube assembly such as focusing and collimation. Hence you can't easily defork it if (when??) the electronics fail. Paul
  5. Just seen the price - £4000. This seems like a good deal compared to the original price but just wait until a bit of dodgy Meade electronics goes, result is biggest most expensive paperweight you could buy. Given that the scope is so tied to the elctronics you are unlikely to be able to even use the OTA if something does fail. I'd be cacking myself every time I pushed the "on" button in case it didn't power up. Just my opinion though............ Paul
  6. I wouldn't touch it with the ye olde barge pole. IF you get one with completely functioning electronics it PROBABLY would be a wondeful scope. IF you got one with some broken electronics or some electronics that subsequently broke you would be stuffed. Ask yourself which is most likely. I would bet the second and then who would mend it?? Don't know the price but you'd be better off with an ACF (I know these have a longer FL) if you're after this design of scope. Paul
  7. To me Maplins rates down there with Hellfrauds (Halfords). I have had 2 things not work and tried to return them for a refund, each time they initially refused as I had left it more than their 28 day return policy and would only offer a credit note. Only the threat of Trading Standards, as this was clearly a breach of consumer law, resulted in a refund. In the 80s they used to be really good but are now just glorified China sourced box pushers. The place I use far too much is CPC. They have a much better stock than Maplin, are generally cheaper and they really do deliver next day. Highly recommended. The only downside is that there is so much stuff you never realised you needed (well wanted) Paul
  8. Another reason for this inequity is the importer - or was until recently unless things have changed. For both Meade and Celestron there is just one importer into this country for each one. For a scope in this company to have a valid warranty in this country it has to have been bought in this country. That means no matter which place you buy the scopes from in the UK you have essentially bought it from the same importer. I suspect that the importers will only let a company sell the product for a set minnimum price in this country. Hence virtually every price advertised is the same. There is just no competition at all and this amounts to a cartel/price fixing in all but legal name. If we could have open and honest competition the prices would fall. Unfortunately the astronomy market in this country is smaller than the US and we are taxed until the pips squeak. The US is different but as stated above we do have more consumer protection. Paul
  9. Bing, bong.......... "Virgin regrets to announce that it's Virgin Galactic service at 1pm today to the atmosphere has been cancelled due to the wrong sort of leaves on the runway. An alternative bus service is available and the in-flight refreshments of crisps and second rate Costa coffee will still be available at a predictably inflated price of £25 each. For all other Galactic journeys please do not lean out of the windows whilst travelling and have your tickets ready for inspection or you will be jettisoned immediately. Have a pleasant day and please use Virgin again."
  10. You could actually just get away with a single power cable. I have an observatory and can control everything from the house just via the mains. I then use my desktop to control via remote desktop. You can get ethernet over power line such as this - there are a multitude and I got mine from fleabay. This means that you just need one mains lead that supplies the power and the network. The only points are 1) There are 85 and 200mbps varieties. The later are mainly for streaming video and I am happily using the lower speed variety. 2) There are 2 protocols - Homeplug and (I think) Powerline and they don't seem to be compatible 3) You cannot have a filter/surgeprotector that the adaptor plugs into as it filters out the signal Other than this it works a treat and is much easier than the expense/hassle of running an extra ethernet cable. As mentioned above do not even think of running USB etc from the garden to the house as it will be totally unreliable even if it does work. Paul
  11. I agree with most of what you said but it is not the dithering that reduces the hot pixels. You have to have sufficient subs so that your combine method can statistically weed out the hot pixels. You, therefore, have to use the correct combine algorithm too. Now the longer answer No detector is perfect. Most (all??) will have some pixels that are hot - ie show up white in the exposure. If you took subs with the CCD in the same place then to your processing program it may be a star or may be a hot pixel, it doesn't know. What you want is a method of allowing the statistics of stacking to differentiate. So if you move the CCD a bit between each sub then the target falls on a slightly area each time. This means the subject is in a slightly different place of the shot each time BUT the hot pixels stay in the same place. This allows the stacking process to statistically drop the hot pixels. There are a number of different methods of stacking, some are designed to reduce outlier pixels (median, SD Mask) but some will not (sum) so the method of stacking is critical too. And that is just the first part of your question. As to how then it depends on the capture software you use. Paul
  12. I have tried PixInsight on 2 occasions and hated it. I really, really wanted to like it, hence giving it 2 trials, as I wanted a purpose written programme (rather than Photoshop) and it should appeal to my scientific/mathematical view of things. However, I found that the programme almost revelled in complexity with no explanation at all of what the parameters do. I gave up with 2 trials that I had as I had better things to do with my life - I really just could not get on with it . I am impressed that are able to achieve anything useful - that is a good result and well done. Paul
  13. Curvature - you cannot adjust that unless you get a flattener, which you already have. Tilt - 13% is not too bad really. I may be wrong but tilt is more likely to be due to your camera not being orthogonal to the optical axis - don't know if collimation affects this. Collimation - again that is not too bad really. You are pretty close and the problem in the UK is that our skies are usually not good/stable enough to allow as good an adjustment as you see on American websites. If you want to tweak it more then you need to make a number of measurements. If they all pretty much agree then the error is a true one; you can then make a small adjustment. Recheck with a few further readings. You will find that you get to a stage where sequential readings bear no resemblance to each other - you are then seeing/atmosphere restricted and you will get no further. Also CCDI has a single defocused star collimation method as well as a long exposure field method; don't know which you are using. From my messing with CCDI (and my Meade ACF) I suspect you are not far off as good as you will get in the UK. I think you are in danger of trying to be too perfect now. I have been there and it is a wasted fight as you will never be perfect. Your latest shot is a massive improvement but focus looks a bit out on the photo. Is this a crop or the full screen? I would think that one more night just to do sequential measurements and you should be there. Paul
  14. Sorry was going off memory , thought it needed the full version. As for t-point then this is "supposedly" very accurate as it measures the polar alignment using most of the sky whereas PAM uses a portion xx degrees across (depends the setting you use). However, polar alignment with T-point can be a bit of a faff with various correction factors to sort of guesstimate. If I didn't have T-point I wouldn't buy it for the polar alignment capabilities, plus you need the Sky Professional to run it. But T-point is unbeatable for pointing correction (better than Maxpoint) and I can get repeatable pointing all over the sky to less than 30 arc seconds; every target is bang centered even after a meridian flip. In your shoes I'd go with PAM but the J2000/JNOW issue limits it. You could always get it pretty accurate with PAM and then use another method (drift or one of the programs to do drift with a CCD) to refine the alignment. Paul
  15. Polealign has good and bad points. Good free good support (Yahoo group) easy to use (when you have figured it out) good feedback about the changes in alt/az you need to make much quicker than drift aligning Bad can be tricky to setup you need reliable plate solving you need the full version of Pinpoint is only calibrated for J2000 this really limits its usefulness so it will give you the pole 10 years ago there is a spreadsheet on the Yahoo group to help with the recalculation I think the authors are working on an update for this Overall it is very useful but I now use T-point because of the J2000 issue. However, for a quick alignment that puts you within a short distance of the pole it is very useful. So if I was setting up from fresh I would use this first and then move onto T-point to fine tune things. Paul
  16. It can be a bit confusing but they will ONLY act on a layer with an image in it, and only on that layer. I usually copy all the layers and then flatten them - shortcut is select all layers you want and press shift-ctrl-alt-E all together - yep 4 buttons together(don't ya love shortcuts ). Then run the action on that layer. As said above they should be 16bit RGB images. Paul
  17. Rich, Teadwarf is completely correct. I have had a look at the FITS file and the distortion is not the same across the whole image. Feel a bit daft I hadn't checked before I know you say the optical train seems fine but can you take a photo? Just because there feels to be no movement it can sometimes be too heavy and cause flexure even if it is tight. Before you start faffing with CCD Inspector you need to know if your imaging train is roughly aligned with the optical axis. Do a simple VISUAL collimation - this is (relatively) easy. Then attach your camera and see what the photos are like; you could then do the collimation via the camera. If the collimations are wildly different you may well have flexure etc and no amount of messing with CCD Inspector will help as you will get very frustrated. CCD Inspector can help with the above but can be a right pain at times. Rather than add another thing into the mix try to do it roughly first as above. Paul
  18. I take the lazy approach. I have Noel Carboni's actions. The "make stars smaller" action is good but sometimes not as selective as I want. Therefore I run it multiple times on a new layer until the star(s) in question are the right size and then use a mask to just show them. The advantage is that this can be run a number of times until the size and effect is just right. Paul
  19. Yes it is a good deal compared to the new price but even £23,000 is bonkers. Yes I can see why it would cost that much given the need for perfect blanks and all the grinding. Just because something is priced to represent how much the raw materials and workmanship cost doesn't make it good value. You could have a toilet made out of solid gold that cost a million - if you sold it for 500k it would be a good deal, but I still wouldn't have it . Extreme example but just making what my original point was.
  20. I don't doubt this is a lovely scope but why? This is being sold on "cheaply" at £23,000 when it is 36,000 euros new . For the price you could have a Paramount or Ap1200 and a 16" modified Dall-Kirkham with change for a load of accessories and decent camera; and still have change. Just don't get it. Still I am sure some one will be along to put me right Paul
  21. Rich, there we are - said a PHD user would be helpful. It would sound logical what MarkF has said. You would need to sat Maxim up in a similar manner (using the relays setting). For the moment I would go with PHD as this sounds like your answer. If this does sort it then you know your setup is fundamentally good - you could then consider using Maxim to guide as well as take piccies. Paul
  22. If you have Maxim then it would be best to use that for capture and for guiding. Be careful to read the help file carefully as the guide setup is really intimidating to start with but actually straightforward really. The graphing facility allows for a long time period and quantifies the degree of error. I can fully recommend the plugin from John Winfield that means you don't have to a normal calibration - all you do is plate solve (using the built in Pinpoint engine) and voila the calibration is done. Just make sure the flip settings are correct the mount is correctly setup via Ascom you of course will need a copy of the GSC catalogue from here if you don't already Paul
  23. "if astrometry.net has solved it correctly, the trailing of the stars is neither in RA or DEC: " That is at odds with the PHD graph which implies most of the error is RA - though I have not used PHD so don't know the ins and outs of it. It would really help to do a few runs over a reasonably long period of time. Periodic error should be easy to spot and may imply a mount issue. Nonperiodic error may imply wind, snag, CCD or guide scope attachment issues. Paul
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