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brancusi

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Everything posted by brancusi

  1. The large version is a stunner - great work!
  2. A warm (well, actually cold wet and windy!) welcome from London!
  3. Super shot of one of my favourite targets. :-)
  4. Thanks! Are there any that have better quality mirrors? Or is it a case that if you optimise your optical train for imaging, you're compromising any visual work and vice-versa?
  5. Hi I'd really like to be able to quickly change between some visual observing and astrophotography and I'm thinking a flip mirror could be the way forward. My camera only has a parallel port output so full frame readout takes over 60 seconds which can make it slow to find and centre a target the way I would like and having the option to flip to visual mode will have all sorts of advantages. Ideally I'd have gone for the Meade flip mirror as I have a LX90, but I guess any will do so I've been looking at the vixen one here. Is the vixen suitable do you think? Is there any real difference between this one and (say) the Skywatcher or the OVL? Should I look for a 2" one in case my eye piece collection grows? Thanks! Roger
  6. Thanks I'm looking at the field of view you'll get with the Celestron and G3 and I think that would be tough to do at f10 - I'd suggest adding the focal reducer or switching to the ES80 without the powermate. Exposure wise, I'd say start short to check your guiding and then ramp up as you have confidence in the setup. If they're looking good at 60", try 120" and then 300" and check your stars are still round - if you can get nice round stars at 5 minute subs you'll get great results when you stack them. As for when to start - it depends if you want to shoot a few things in the same night, or want to spend all your efforts on M51. I'd maybe do 1 hour L (12 x 5 mins subs) and if you can bin the camera 3x3, you should be able to get away with 20 mins each R G B. If binning 2x2 you would need longer R G B, around 45mins each as well (given the filters) and that means you're looking at a 3 1/4 hour session - I'd likely be more concerned about when I would sleep rather than the height of the object and generally I would do L first so that if anything goes wrong later in the night, I still have a good mono shot to process. Strong disclaimer - I'm not remotely expert at this!
  7. If (and I stress the if bit) you have had previously good results auto-guiding the Celestron without a focal reducer, then that will be the most challenging option (and so the one I would choose!) - however guiding at a focal length of 2m will be a test if you're not well set up for it and I think a more sane approach would be to add the f/6.3 focal reducer to both lower the exposure time and make the guiding a little less critical. M51 is fairly bright, so you can get away with short subs which puts less stress on the guiding and polar aligning - for example my first attempt at M51 with a similarish setup (LX90 on AZEQ6 with ST-8E) used just 15 x 30 second exposures unguided and whilst it's a bit rubbish, you can see that it is M51. At the end of the day, your sub length is determined by the accuracy of your guiding and assuming you don't want field rotation, the accuracy of your polar alignment. If you can guide up to 10 min subs that's likely to give you some pretty decent data and if you can bin your CCD, you could shoot the RGB 2x2 binned to save some imaging time - you will get the detail from the L at full resolution. Other more experienced imagers are likely to have a better idea of the number of subs for each of LRGB that make sense. Enjoy the night whatever scope you choose and do share the images when you get back!
  8. I think the content and people on the forum make it what it is - great - however I find it much, much slower than other sites with pages often taking 20 seconds or more to load. This is pretty regular and seems unique to this forum compared to others I use. Whether I'm using a PC, Mac, Safari, Chrome makes no difference and my internet connection is generally around 50Mbps so it's not a local issue. Does anyone else find this? Roger
  9. Hi Brian I de-forked my LX90 earlier this year and put it atop a AZ-EQ6 and love that combination. My first light with the combination and ST-8E is actually a bit (well, a lot) rubbish and it's actually un-guided as I needed to rotate the camera to get a guide star on the guiding chip and couldn't be bothered, oh and the polar alignment was well off too ... so it's not exactly an image that will sell the idea to you! I think anyone would say that guiding at 2m is tough and you may wish to consider a focal reducer in your image train? Meade do a f6.3 field flattener / reducer that will make the combination more forgiving and also likely a better scale for many DSO - but I like a challenge and so at present I'm working at 2m and hoping that the built in guide chip of the ST-8E will mean that I've eliminated any flexure concerns and should be able to guide reasonably well. I'm waiting for the clouds to clear before giving it another run at 2m now that I've sorted out various other software issues and am reasonably confident I can do a better polar align. We shall see. As you know the OTA on the LX90 weighs in at 10Kg, but being pretty short, even with a camera hanging off the back, I'd personally have thought your NEQ6 will be fine - even with the st80 on top. Some may say use the lx90 to guide the wider st80 of course ... Roger PS. I'm pretty new to all this as - so other more experienced folks may give sounder advice!
  10. Very nice indeed - I'd be well pleased with that
  11. Envious of the views you would get of the aurora, welcome to SGL!
  12. It's an old photo from 2011, but it reminds me how poor the skies here in London are and what fantastic skies are still possible elsewhere in the UK when conditions are right. This is a pair of 1 min exposures aligned more for artistic than pure astronomical requirements, so try not to be too offended by the lack of accuracy! The pair of original photos were taken on a Nikon D90 with the 10.5mm fisheye lens on a basic tripod. Image on Flickr with more information Thanks for looking!
  13. Thanks everyone, liking the advice about a planetary camera - making me think about a second scope as well now ... is there no end to astronomical spending ;-)
  14. Thanks! Should I be worried about the length of the kit hanging off the rear? I have a pretty heavy SBIG ST-8E and the thought of a barlow in line makes me wonder about the mechanics. Should I use my diagonal for planetary imaging so that the kit gets stacked vertically or does this really not make much difference?
  15. For prime focus astrophotography, we can use focal reducers for a wider field of view. For planetary imaging, it would be nice to get closer - but all the barlows I can find are for eyepiece use, not for screwing to the rear cell of the SCT. I am just failing to look hard enough, or is there something inherent in the optics that means adding a barlow to the rear cell simply doesn't work?
  16. You could always consider de-forking it and putting on a new goto mount? For various reasons I de-forked my LX90 and put it on a new AZ-EQ6 and am very happy with the result. Not a cheap option I know - but it would breath new life into a fine OTA if you can't find a direct solution.
  17. I found the changelog here in case anyone else struggles. Can't say it has answered my questions though, but I guess I could just work through the old versions I can find online and see if any make a difference.
  18. My HitecAstro DC Focus controller arrived yesterday for use with my Meade 1206 focuser for my LX90. From the controller point of view, everything seems fine, I can see it driving the focus knob in each direction and using the supplied software controls I can do the same at various speeds - excellent! FocusMax is giving me a few problems though. Version 3.8 won't drive my old version of Maxim DL 3 that I'm stuck with as it supports the parallel SBIG cameras and last night I found a repository of older versions so tried out 3.1. Semi-success in that it will drive Maxim for me OK and when I went through the 'first light' procedure it happily found a star and then iterated on focus - but it never seemed to complete - it kept incrementing the focus and ended up off-scale - however the star itself didn't seem to be changing in focus, it just looked like variable seeing. I guess I have 2 questions really. 1) Does the focus speed set on the controller have any bearing when driven from software? I kind of imagine the driver would set this itself, but maybe not. 2) Did I pick the one old version of FocusMax that has a bug? I can't find a changelog anywhere to tell me which version might be better. Any experts out there with a similar setup who might know? It seems that now FM has gone commercial with V4, there's no support for V3 from the creators. Roger
  19. Once you get the hang of a few details, I find AT to be indispensible. For me the main gotcha's seem to be; 1) ASCOM needs to think your mount is pointing in roughly the right direction to start with and this means setting the date / time on the mount is a key step otherwise the RA is too far off to be usable. This has caught be out at least twice with my AZ-EQ6 and it's possibly an argument for moving to EQDIR which takes the handset out of the equation. I don't do any other start alignment before using AT. 2) Making sure you actually have all the required index files is, er, vital. When I started I hadn't downloaded the correct set and my f10 wouldn't solve at all. I've found that I only need the index sets 5 and 6 to be able to switch between f10 at 2000mm and using the 6.3 focal reducer. If you know which setup you are using, you can move index files out of the AT folders so that it only has the ones it needs - makes solving much faster. 3) If AT solves (it's great at this) but your scope won't sync, it means that ASCOM is likely rejecting the sync command because it thinks it is too far away from where the scope is pointing now and it will reject the sync command in a huff because it thinks you are being stupid. See point 1) 4) If AT won't solve and you think it is your image, try uploading to nova.astrometry.net before blaming your image. See what the online service thinks is your centre RA/DEC and then look at where ASCOM thinks you are pointing, check that you aren't restricting AT to only searching to within a few degrees of the target as that's another way you can get caught out. Once you get the hang of it though, it's a huge timesaver and I can be aligned and getting DSO bang on the CCD within a few minutes of firing everything up - and that's for a scope on a field tripod. Can't quite make it to 2 minutes as I'm using an ancient Laptop for plate solving and so it generally takes 3 minutes or so - but I love the freedom it gives me.
  20. The bar for astrophotography hasn't so much been raised, as catapulted to an altogether more elevated place - approximately 1,600 light years away. Inspirational work.
  21. Now that we finally have a garden rather than a flat, I've been able to setup my trusty LX90 again and start to do some imaging from SE London. Last month I de-forked the LX90 and attached it to a new AZ-EQ6 and over the last few nights I've been setting up an old laptop with a parallel port so that I can use my ancient ST-8E. I lost a couple of hours last night with Astrotortilla plate solving but not syncing despite it having worked the night before, finally twigged that the mount hadn't accepted the time correctly and so RA was too far out to sync. Solved that and we were in business. There wasn't a nice guide star near my target (I could have rotated the camera, but it was getting late!) and the mount is only roughly polar aligned, so this was 15 x 30 second un-binned exposures roughly calibrated with bias and dark but no flats. Aligned in Maxim DL 3 although really I should have rejected the worst subs. It's a bit rubbish really - but it lays down a marker from which I can improve! Roger
  22. Fantastic help - thanks all, and the clouds have even parted for long enough for me to test it all now works. Getting the home position roughly right was indeed the key to it.
  23. My question is probably best expressed as - how on earth do I sync the telescope (AZ-EQ6 via EQMOD) through Stellarium on a star near the pole? I'm trying to establish a workflow where I use plate solving via AstroTortilla to sync the scope setup to the sky before an imaging session, as such the scope is accurately polar aligned, but otherwise UN-ALIGNED when I start. I thought I would be able to do this; 1) Point telescope randomly at the sky 2) Take a 10 sec exposure 3) Plate solve to find central RA/DEC 4) Sync the scope to this position It seems that steps 1 through 3 are fine - I did this last night and could plate solve every image I took - but NONE of them would sync. I was getting error messages about the sync being ignored because the delta in position was too large (apologies I didn't write down the exact message) and so I could never get the ASCOM Ra/Dec to match the solved image :-( In desperation I put the scope roughly in weights down pointing north and then tried to use Stellarium Scope to sync on Polaris to at least narrow the error so that subsequent plate solves would work - but every time I used sync, the command was simply ignored unless I tried to sync on a star that was a long way from the pole - it felt that the software was blocking me without telling me what was going wrong. Is my plan to do this without an initial one star alignment flawed? Is there really no way to force EQASCOM to think the scope is at a specific Ra/Dec? It could be I was just too cold last night to think clearly but it felt that I was so near and yet so far from getting it all to work ... Help appreciated! Thanks, Roger
  24. Depending on the weather it can be pretty essential I find.
  25. I'm running MAXIM DL 3 with my ancient ST-8E (parallel port version) and am trying to determine whether or not I can upgrade to a more recent version of Maxim. I get the impression that they have now dropped support for the parallel port cameras, but does anyone know the last version that DID support SBIG cameras like the ST-8E (Parallel). I've tried reading the release notes but haven't found the right thing yet and just thought someone here might know! Thanks!!
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