DaveS

Thanks! Another update. Put the West framing in place. I wasn't going to do this yet, but for reasons I'm still trying to understand, the uprights that I cut (All near as dammit the same length) are too short for the East wall. The bearers are level N/S, and, as far as I can tell, E/W. They fit for the west wall, and for the south wall. I'll be ordering some more wood soon. so will order some for replacement Lots of elements that are out of square, but hopefully won't affect the final outcome. Now trying to decide what I can be getting on with, possibly laying the first lengths of track. I also want to get an idea of the final roof height. But first, give my back a rest.

OK, time for another update, I've been off the forum all day working on the obsy. I now have the North wall in place, having had to go back and forth sorting out some out-of-square elements. I also have the roof bearers on, but only screwed down at the north end, to leave a little "give" to allow for squaring up. If some of the noggins (Why do I keep thinking of a cartoon viking lol) look out of square, it's because they are! Nevermind, I think I can live with that. The next jobs are the East and West walls, keeping the south (Facing the camera) open for getting stuff in, but will take more care over making sure everything is square. I'll be ordering *more* timber as I ran myself out due to some wastage during cutting. A lot of this has been a learning curve! Also need to order a winch for mounting the heavy stuff. Heigh-ho!

After actually *looking* at the 1:10 scale drawing I made while I was planning the obsy (dur...) I went out during a brief fine spell and swapped uprights on the north side and added the door frame. Still needs a lot of work, perhaps tomorrow as the rest of today looks horrid. I am actually finding the angle brackets very useful for holding the uprights in position, as being on my own it's very easy to get things out of alignment, especially for me, as I can make a complete pig's ear out of *anything* .

Thanks for all the feedback. I've been giving it some thought and have decided to make a few changes to my plan (Which my ad hock building allows). Firstly, on taking the advice offered, I think I will leave out the brackets on the intermediate uprights, at least for now, screwing them directly to the sole plate and bracing with noggins. This I can do now-ish. Also I will replace the already cut uprights on the north side with the higher ones I really need for the north wall, which is higher than the others as it has the door in one corner. This will enable me to remove the angle brackets and use the doorframe for bracing. I'm off to the garage to slap some end-grain wax on the uprights i've already cut and measure up for some additional lengths of timber.

I guessed I'd done something back to front. Partly the reason was lack of clear space to lay the walls down, but it just seemed more logical (At the time) to lay a foundation plate and build up from there. Well, I don't want to dismantle the whole lot if I can help it, plus the uprights were cut to a length based on screwing them to a sole plate and putting the rail on top. If I build a complete wall that will result in walls higher by the combined thickness of the top and bottom rails. Let me think about this overnight and possibly tomorrow, as the weather is going to be rubbish I don't use nails if I can help it, anyone who's seen me trying to hammer nails in will know why, Cross dominance plus, I suspect, a degree of dyspraxia sees to that. I tend to hammer nails in sideways Edit: Swear filter changed the (Very mild) slang expression I'd used

Thanks James, yes it's been a while, having to fit this in between downpours. I did manage to drill out the 8 pilot holes for the pier while there was a lul in the rain. I'll see what I can do tomorrow with regards to the intermediate uprights.

I may have made a small mistake with the angle brackets. The one on the north-west pillar pointing right is where I'm planning to put the door. So either remove it and screw the door frame directly to the corner pillar, or else leave it an put in short noggins so the door is a little (Say 6" / 15 cm) away from the corner. I'll think about it overnight. Still have to treat the end grain of four more uprights, the door frames, and the track bearers.

Construction begins, yee-haw!* Fixed up the four corner posts, each consisting of two uprights screwed together and fixed down to the sole plate with right-angle plates, plus diagonal screws into the sole plate. slightly wobbly as they stand, but should be more rigid when I get the intermediate posts and noggins in. Planning two intermediates per side. The greenhouse is being used as a temporary construction shack. I will leave the south side open for the moment as I may well want to mount a winch on the long rail bearers (Still to be fixed) to aid in the movement of heavy / fragile technical stuff. Waiting for a bit of dry weather to slap some Creocote on the uprights, Wed looks good. Meanwhile measure up for the spacing of the intermediate posts and noggins. took a delivery today of lighter wood for the roof. * 'cos I'm a cowboy builder, yeah!

The place for a BIG telescope like the OWL is lunar farside. 1/6 gravity makes supporting the optics much less onerous, plus being away from earthlight. Oh, and vacuum, so no air turbulence (Or CLOUDS!)

Sorry Ole, my question was rhetorical and aimed at a general audience. My DDM mounts don't need guiding either and are certainly capable of that sort of tracking accuracy.

The figure to think about is arcsec / pixel. As an example, for my 130mm f/7 at 910mm I get 0.85"pp. Can your mount guide to half this value? My DDM60 can, and the DDM85 most certainly can. Also I dare say most camera lenses have so many compromises that they return a Strehl value that would be treated with derision on this forum. The other think to consider is binning, at bin 2 this gives a more manageable 1.7"pp and around 15 mp resolution.

How are you finding this camera? Does it live up to the spec (I nearly said "hype" but it isn't really) regarding amp-glow etc. I'm really trying to avoid buying one of these as I know I can't truly justify it, but images like this make it very hard.

FWHM, Full Width (at) Half Maximum HFD Half Flux Diameter. I think.

There was the OWL, the OverWhelmingly Large telescope that ESO proposed with a 100m dia mirror. The ELT is the cutdown version. Maybe OWL will get build sometime.

Good to see it's gone to a good home. Seriously considered taking it on, as I live just up the coast from Ade, but my horizons are a bit high for a ground level dob. Plus the size might have been a bit too much for me.

Yesterday RM delivered a birthday card from my cousin in New Zealand, postmarked the 17th.

As far as I can work out, the only mono CMOS cameras are the ASI1600 clones and the 6200 varieties at a fairly horrendous price. That is, until you hit the FLI keplers at a mind-numbing £16k a time. slightly more choice in CCD.

Definitely. Unfortunately they are limited by the sensors that Sony or Panasonic churn out. I guess there's not much market for mono sensors. The square format is ideal for imaging. * sigh* thinks of 6x6 on 120 film

I have 3 nm Astrodons, even so I wouldn't try [OIII] with any more than a sliver of a moon, and that well out of the way. Even [SII] is "iffy". I have managed reasonable results with [NII] but that's not a widely used filter.

Dithering and Darks are both useful, dithering plus Sigma stacking will get rid of most satellite trails. I'm not familiar with the 383, as my CCD is a 694 sensor which is quieter I use Bias instead of Darks, but I think with the 383 you will need Darks as well as Bias.

Ah, I didn't see that one, buried in among the dob covers. Yes, that would do nicely.

Don't skimp on the quality of the cover. I think This would cover your 'scope on an NEQ6 mount. The odd shape of an EQ mounted 'scope requires a rather big cover. I don't see a specific 10" Newtonian cover so looked at a SCT with a long enough top length.

+1 for Telegizmos. I have two for my 130mm apo on DDM60, and HEQ5 with various 'scopes. Just got another as temporary cover for the ODK12 on DDM85 while setting up the obsy.

Desperately sad. I've just heard it now on PM, buried down among the "other news". That alone makes me spit, shows just how low science is rated on the beeb, below "celebrities". 70 is no age at all.

That is so sad. do you have a link, as the Beeb don't rate it high enough to put it on their site yet.