JamesF

I was tempted to make the warm room larger, but when I actually looked at how much space I use when I'm working day-to-day it's not a huge amount so I'm hoping that what I've planned will be sufficient. It's quite possible that I won't have the main door entering the warm room which should free up some space. It all comes down to the wall height really, though given how low the doors are on some commercial observatories perhaps that shouldn't be such a worry :) James

It feels very positive to have started. I think I've been promising myself this since my son was nine or ten and he's just turned fifteen ? I suspect it's going to be quite a long journey. I have someone lined up to make the piers though he's apparently a bit busy fixing farm implements at the moment and doesn't reckon he'll have much time for the next month. He has a good reputation, but I'm still not sure I want to pour the concrete for the pier bases until I have the actual metalwork to line up the mountings. I know I could provide him with a jig with the actual hole positions, but working in IT for thirty years very much gives you the mentality that "if it can go wrong, it will go wrong". And whilst I can easily get power from the "beer shack", I really ought to upgrade the cable between there and the house and provide a proper earth. I want to run hard-wired networking from the house too as the wifi connection I have to the beer shack at the moment is a bit hit-and-miss. If I'm in by the time the clocks go back, I shall be very happy. As will my wife, who will no longer have astronomy gear cluttering up the house. James

I've just been out to check the view over the house at the moment. The Moon is clearly visible and Jupiter is pretty much at the roof ridge height, so I think the house should only block no more than twenty degrees above the horizon. I won't be able to see some of the Messier objects in Scorpius, but I think I can live with that. James

There is actually an ancient (Neolithic?) hill fort less than a mile and a half away, where a pot containing a large number of Roman coins was found in the 1940s. I've not had any such luck here though. I did find a very badly corroded French coin from the reign of Napoleon III in the veggie plot a few years back, but other than that my interesting archaeological finds have been limited to dozens and dozens of old-style (thick glass with a tapering neck -- people older than 45-ish who grew up in the UK will probably remember them) milk bottles and a quern stone from a domestic-size grain mill. The Napoleonic coin is interesting though. This area has a long, long history of agriculture and is really quite poor overall, so probably not a lot of population movement has occurred outside the locality historically (I'm told the farmer who owned our house until the 1960s only travelled as far as the coast, barely ten miles away, twice in his life). How did a French coin from the 1850s end up "lost" in a field here? I have thought about getting a metal detector to see what I can find, but I know that so much household and farm waste has just been dumped everywhere until the mid 1980s that I'd be most likely to find bits of scrap that someone had buried in a hole just to get rid of it. James

I've been promising myself that I'd build an observatory for years, but life has just got in the way a bit and I never managed to get started. Given recent events with my brother however (see posts elsewhere) I decided that I should really get on with it, so ordered some of the materials with the view that if I had the stuff here then I could work on it as time was available. My plan was always to build in the "upstairs field" (a name given unintentionally by my son to the field at the top of the slope in front of the house) but at the moment there's no easy way to get power there. That may still happen in the future, but for the time being I had to look elsewhere, which has not actually been too easy as very little (almost none) of the ground around our house is level and some of what is level merely acts as a collecting point for run-off water when it rains heavily. My chosen site is this, which is next to "The Beer Shack" (which already has a power supply that can be used for the obsy). The closest four stakes represent the corners of the actual building with the last one where the roof will roll off to. It's flatter where the cement mixer is, but there was about 100mm of standing water there for much of last winter ? The size of the obsy will be 4.8m x 2.4m including a 2.4m x 1.2m warm room at the far (north east) end. I intend to have multiple piers to allow a permanent white light/Ha solar rig to be set up on one with night-time kit on another. My design isn't too different from Astrokev's current build, but I don't yet know how tall my piers are going to be so I don't know how high the walls will be which in turn means I'm not sure where the door is going to end up. Once I have the floor deck built and can check sight lines I'll make those decisions. This gives a better idea of the slope. I'm not entirely sure how the corner of the stone wall appears to be vertical, but the shed on the top right looks to be leaning quite significantly (which it doesn't). Local gravitational anomaly, perhaps. And from the warm room (north easterly) end: The other major compromise with building here is the view to the south west. Or more specifically, how some damn fool built my house in the way without considering that several hundred years later I might want a better view. The view to the south east is similarly obstructed, but by a mature ash tree. However, I went out the other night and could clearly see Jupiter over the roof of the house so I don't think it will be too bad. The ash tree is probably on borrowed time too, though I'd not remove it just because it was an obstacle to astronomy. Once I'd mowed the grass I wasn't entirely happy about the steepness of the slope. The floor deck will be built off six concrete pads and the pad at the bottom of the slope would have been over 600mm high. To reduce the height a little I decided to move everything about another metre away from the house. That done, this afternoon I started digging out the space for the first two pads. Having the right tool for the job should save a lot of time ? Sadly I was a little slowed down because I managed to jump one of the tracks off the digger. I knew I needed to check it but I forgot and paid the price. Fortunately it wasn't too hard to lever back on with a long steel bar whilst holding that side of the digger in the air with the bucket and running the track forward (not recommended practice, I imagine, but probably happens far more often than anyone will admit to ? I got the shuttering in for the first pad late this afternoon, recycling the base of a trailer in the process, though I have to admit I'm not entirely sure how reliable the ply is any more. It may not look it, but the spirit level does actually say it's level in both directions. I managed to get the shuttering in for the pad on the left (also recycled, this time from a shelving unit that has seen better days) as it was getting dark. Need to check the levels again in proper daylight. I'd really like these two pads to be a bit lower, but the top of the one in the photo above is only 150mm above ground level and I'm not sure I want to go closer to the ground than that with the timber. Perhaps 100mm clearance would be sufficient. I shall ponder on it before I start the next one. James

When I read the title I thought perhaps you were going to use it for a PST stage 2 mod James

Hah! Posted at the start of this thread, as it happens Not entirely with it this evening. Just got in from two and a half hours roasting on the poolside (in Wellington again), torturing swimmers. James

It's been shut for quite a while now. And sold off, in fact. I believe I posted about it at the time. I suspect someone has moved in and is actually living there, though I'm not sure it would be considered fit for habitation in the general scheme of things. James

Sad news I must drive past the old shop at least half a dozen times a week and it's always a reminder of SCS (where my first "proper" telescope came from). James

I'd not seen this thread before. Very inventive James

I agree Here's one of the stars from the M81/82 image that looks to have diffraction spikes: And this one from the Orion image I would say shows signs of further diffraction effects (alternating dark and bright bands) between the upper pair of bright spikes and again between the lower pair. Having cropped the image it actually looks even more obvious to me. I could be wrong there though. James

Diffraction spikes added in software generally look "too perfect" when I've seen them. These don't look like that to me. I'm sure I saw them in the M81/82 image as well. I'll have another look. James

That is of course a possibility, but it's not unknown for refractors to have diffraction spikes and you'd probably even find some examples on this forum. To be fair I am struggling to think what would cause them to be quite so strong with a refractor. I'm sure you could always ask them to explain the cause James

Yes, they're clearly there on the M81/M82 image too. The stars in both those images look quite unpleasant shapes in places too, and in a way that for some not entirely quantifiable reason makes me think it's an optical problem rather than drift. I guess the main diffraction spikes could be down to something intruding into the light path of the refractor (lens spacers perhaps?) but there are quite a few smaller ones too. No idea what might have caused them. I'm not sure however that these are issues that will be a concern to the target market. James

From that site: "Below is a cropped single 10 minute (602 seconds to be precise) or our Star Adventurer with a 200mm EF lens (=320mm focal length due to crop factor)" Gah! I hate it when people suggest that using a crop sensor somehow changes the focal length. How do they imagine that works? Does it somehow magically introduce another lens? I do like the counterweight made from three drink cans though. That's rather neat and handy if you want to take stuff on holiday without weighing yourself down with lumps of steel. James

Certainly appears to have been styled for the iphone generation. James

The Ubuntu one for download might well still work. Give it a go and let me know how you get on. If it doesn't work then I'll see if I can sort something out. James

There's a download for Ubuntu 14.04 on 32-bit ARM here: http://www.openastroproject.org/downloads/ If you have a later Ubuntu release then there's a possibility that it will need to be built from scratch as I don't have anything later installed to build on at the moment, but it isn't a total nightmare to do that. James

Oh dear! It has been a bit fierce though, hasn't it? We're having some work done in the cellar at the moment and have to empty it, to which ends I've bought a cheap prefab wooden shed that was delivered today. Unloading that from the delivery truck was a bit more exciting than I anticipated James

There are also wifi and wired ethernet interfaces for the Arduino, so transferring data that way may be possible? No idea how much network-level programming is required though. James

Or perhaps just make a small table of offsets and subtract the nearest one to the data value, to give better accuracy across the range? James

I think that would make a lot of sense. It seems obtuse to only return a meaningful error value for two of the possible error conditions. James

Perhaps this might help? https://stackoverflow.com/questions/19765037/arduino-sketch-upload-issue-avrdude-stk500-recv-programmer-is-not-respondi The third answer looks to have a lot of information that might set you right. And there are some other ideas here: https://arduino.stackexchange.com/questions/17/avrdude-stk500-getsync-not-in-sync-resp-0x00-aka-some-dude-named-avr-won James

Sadly no, it won't work on any ARM device as far as I'm aware. There's no reason why it shouldn't, but Altair don't provide ARM binaries at the moment. James

One of my "simple ways to judge a dark site" is what you can see at night when the sky is very heavily overcast. If you can't see your hand in front of your face when dark adapted then it's really quite dark James