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About eifionglyn

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  1. So tonight we have the opportunity to shoot the Moon, Venus and the ISS passing relatively close. I plan to shoot this with my Lumix G9 with a 12mm lens, so 24mm in 35mm equivalent. The 500 rule tells me I can expect a 20 second exposure before the stars start trailing. But in 20 seconds, the ISS won't have moved very far across the frame, in fact Stellerium tells me that I'll take about 3 minutes for the ISS to pass through the frame. What I want to achieve is the Moon, Venus and stars acceptably sharp and have the entire 3 minutes of the ISS pass represented as a trail, in one image. I have no tracking, just a regular photo tripod. What's the best way to go about this? My plan is to take multiple 20 second exposures and combine them, but obviously as the earth rotates the stars and moon will trail too. Is there software that can take the individual 20 second exposures and align the stars in each - but then that will make a curve in the ISS trail. How would you go about capturing this and representing it one image?
  2. So now the AZ-GTI has an update that allows it to operate in equatorial mode, I assume it can do the same job as a StarAdventurer mount - i.e. mount a camera to it for wide(ish) field astrophotography. Why would I pick one over the other?
  3. They're not *that* big - have you seen one in the flesh (in the metal?) The base of the 200 (and the 250 if I remember right - I've had both) fits with room to spare on a 600 x 600mm paving slab, and they're about four or five foot tall. Could be squeezed in a corner or behind a sofa somewhere. Certainly less of a storage issue than anything that sits on a tripod (assuming you're not collapsing the tripod every time). As for Home Office approval - it's always better to seek forgiveness than permission! The 250 was about the limit for what could be shifted about the garden by one person. It also comes in a flextube version which is more compact to store - but heavier. The 200 is easy - often didn't bother taking the tube off the rocker box, just carry the entire thing out in one go. I have the heritage and a 102 mak at the moment - just getting back into the hobby. If I find by the winter I'm getting good use of them I'll definitely be adding an 8 or 10 inch dob to the collection. Probably an 8 - they seem to come up for sale more often, but I do remember the 10 showing me stuff the 8 couldn't - from my skies anyway. I have an ebay alert set should one come up for a good price locally. Jupiter is nearing opposition if you want to impress the Home Sec. Bright, but annoyingly low in the sky in the south east after sunset.
  4. Yeah definitely not coming up for me, on an Android phone or iPad. The comparison chart at https://skysafariastronomy.com/skysafari-6-professional-astronomy-telescope-control-software-for-android.html says that Telescope Equipment Settings and Coordinate Grids and Reference Lines are two of the many features on in the plus or pro versions. Seems likely that ability to flip the display would be included in those features. Now to decide if I want the android or iOS version.
  5. Can’t seem to make it work. Maybe it’s only in the premium version.
  6. I think I'm starting to get the hang of it. Went out last night just after sunset to see if I could spot Mars before it set. I did not, it was either too close to the sun to be visible in the twilight glow, or was hiding behind the clouds gathering in the west, or had already set below the level of the local rooftops (or some combination of all three). Regardless, as it got darker Arcturus was one of the first stars to become visible overhead, so I swung the scope to that, fired up Sky Safari and compared the view in the eyepiece to the app. I found I could move around and follow where I was going, up / the same, left / right reversed. Rotate the diagonal and it goes all kinds of funky, so I will make the effort to set a height for the tripod and my chair that lets me keep the diagonal vertical while still getting my eye to it comfortably. Luckily the short tube of the 102 mak is quite accommodating in this respect. It probably already exists (can't believe I'm the first to think of it) but a 'mirror flip' display option in Sky Safari would be a massively useful thing. As would a split screen function. With a tablet one could have two zoom levels displayed side by side, a zoomed in view showing the current view through they eyepiece and a wider view showing the general area at the same time. Or a sky atlas printed on transparencies. Hmm, Dragon's Den anyone?
  7. Yep, especially when rotating the diagonal to get the eyepiece to a sensible place to look through meaning that 'up' is seldom up anymore.
  8. I had first light since returning to astronomy last night. Picked up a 2nd hand Skymax 102 on an EQ3-2 mount. Found the mount lovely, very smooth and very steady with the 102, and using the red dot finder had enjoyed nice views of M13 and could just about make out M57 - though it was getting lost in the moonlight somewhat. These were found by just popping the red dot over where I knew there were (ish). Then I thought about how to find anything else. I'm used to star hopping with dob and a sky atlas. I pause for a second, wait until I see what edge of the field of view new stars appear at, and that gives me East. West is obviously 180 degrees away from East. And North is anticlockwise from West, because it's a sky map not a ground map. Rotate the atlas till it matches the view and job done, the direction to move to your next step along the hop is now obvious. This is what I used to do with 8 / 10 inch dobs, that I usually equipped with a 50mm RACI finder and a red dot or Rigel quick finder. Should be even easier with an EQ mount right? after all the mechanics of the mount limit the direction of movements to RA and Dec, which match up with lines drawn on the sky atlas. So I leave the controls alone. New stars appear at the East edge and disappear of the West edge. This still has to be true - no mount or optics can change the earths rotation, but how does this factor in with the mirror flip caused by the star diagonal? And what effect is had by rotating the diagonal to get the eyepiece to a comfortable angle to view through. If I rotate my atlas so that East / West lines up with what I see in the eyepiece does that mean that North / South is now reversed? I think it must be. Not sure what my question is really - just trying to work it out in my own head. Can you train yourself to relate the reversed image in the eyepiece to the correct orientation in on the paper? I suppose the easiest thing would be install a 90 degree correct image finder on the 102 and use that to star hop.
  9. So they are! Thankyou! Three dimensions eh, who'd have ever thought to look in the third dimension. Could have looked for hours and not spotted them. Anyway, that seems to have done the trick, I can now twiddle the dec worm shaft with finger and thumb and it feels buttery smooth. Thanks again, Eifion
  10. What do mean by "the two below them"? I can only see two in total.
  11. Picked up a 2nd hand EQ3-2. Am finding the declination slow motion control really stiff. If I disengage the clutch this dec axis itself is smooth and rotates freely, but the slow motion control is very stiff. Im assuming this can be adjusted somehow? I understand the two bolts either side of the little Allen grub screw adjust how tight the worm gear meshes, but even with these fully slackened off the slow motion control is very stiff . Sounds like I need to fully strip it down, clean and regrease? RA axis is perfect.
  12. What did I end up buying? Nothing. I remembered that years ago I’d lent a Heritage 130p to a friend. I asked, and as he wasn’t using it I retrieved it. It still works. Primary was visibly out of collimation, did an approximate adjustment with no aids which improved the view a bit. Red dot finder battery was flat, of course, which limited observation to just the moon last night, but even my 12mm GSO plossl showed me some nice detail along the terminator, some central peaks of craters poking up out of the shadow. So it needs: battery, proper collimating, and the mount taking apart and bearing surfaces checked and cleaned. There’s a stiff spot in the azimuth rotation. I might even add a lazy Susan! If in six months time I’m still observing the night sky at every opportunity then I’ll think about upgrading. If it turns out to be a passing interest then the 130 can just sit on a shelf and get used now and then.
  13. AZ GTi - now that is quite an interesting little thing. According to the specs: Which sounds much like what I want. Same legs could carry an AZ-5 for when I want a pure manual experience. My interest has been piqued.
  14. It depends, I remember my EQ5 you could loosen the clutches and slew the thing across the sky by hand, tighten up the clutches once in the vicinity and the motors would take over. I imagine you could do the same if it were a Go To handset sending instructions to the motors. But then you're back to polar alignment and lugging counterweights around. With an alt-az goto like the Synscan I had the Mak on, you could not, you could only use the handset to slew the scope, which was slow, noisy and annoying! Basically what I need is a butler to slowly turn the RA control for me, but to get out of my way when I want to push the scope myself! I fully realise that I have unreasonable conflicting requirements here. Light, small, simple but durable, capable and stiff, tracked but not go-to, and cheap.
  15. It would be a nice to have. And by tracking I mean RA sidereal / lunar rate tracking. I’m specifically not interested in GoTo. I’ve had it in the past and found it took much of what I enjoy out of the experience, the sense of discovery when finding an illusive target for the first time. So so if there was an EQ mount with a RA drive, that was convenient to carry, store and set up, and could cope with a scope of reasonable aperture for visual use I’d be interested. I suspect I’m after something that doesn’t exist, an EQ5 that’s lighter and smaller but just as capable. I guess heading into the garage and building an equatorial platform might be an option. How hard can it be?
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