Popular Post philjay Posted October 10, 2018 Popular Post Share Posted October 10, 2018 I always fancied some decent 80mm astro bins with decent glass but the ones available are a pricey and usually dont take high mags very well due to short FLs etc. I wanted something I could push to 150x plus. I put the project on the back burner whilst we put our house on the market so was a bit side tracked by that for awhile. I forgot about the idea until last years Kelling when I saw one of Peter Drews achro binoscopes. The idea then resurfaced and has been brewing for awhile only to be reinforced by Peters thread on SGL re his ED80 Binoscope. Now that really appealed. I already had an ED80 DS pro so I was half way there wasn't I? J Also as the house move has stagnated I wanted to distract myself with a scope build project. I started to gather bits for the project in August, looking for prisms to build the IPD (Inter Pupillary Distance) prisms but I held off with the rest of the bits till Kelling thinking I was bound to get stuff there. Nope, the astro boot was very poor this year so came away with nothing for the project except having a long chat with Peter Drew and gleaning tips from his set up. After returning from Kelling I started to properly source the bits, I managed to get all the prisms, then had to wait awhile for the second OTA but that arrived today finally.? I put a lot of thought into what eyepieces to use with the set up and decided to stick with Vixens, I have a set of LVWs and really like them but what I always fancied was a zoom bino. However I've had a Vixen LV 8-24mm zoom eyepiece for years now and thought a pair of these (in theory) would work quite well. I eventually sourced one (not easy to get hold of these anymore) which came yesterday. So initially the rig will be 8-24mm zoom. So I now have all the main components for the project and now need to put it all together. I started last week by making up the IPD prisms. Then last night I tested each prism on Saturn by putting one in the scope, focusing, locking the focus then swapping prisms. Oooops they didnt match, 4 mm difference in the optical path, no good for binos. ? I stripped them both down today and found one prism wasn't seating correctly. Sorted that and now both match. Last night I also tested the eyepieces to ensure they matched using the same technique on Saturn. I put one in the scope at 24mm, focused, locked, swapped - perfect match. I repeated this at the 8mm ends and then for the 12, and 16mm increments and all matched ? The second tube arrived today and after sorting a scratchy focuser I did a side by side test to ensure the scopes were matched also. And yep, swapping eyepieces and prisms the view was tack sharp. No the picture below is not how the bins will be (my eyes arent that far apart) ? I am going to be away next week so won't be able to progress the project but hopefully I will have sorted a design for collimating the tubes and designing a bracket for the rig to fit on my giro 2 mount. I am taking my time over this project because I dont rush stuff anymore, learnt my lesson finally, I want to get it right first time and I want to put some thought into it instead of bodging it initially to get it working then tarting it up afterwards. So watch this space folks Tweedledee, Bottletopburly, +Ibbo and 2 others 5 Link to comment Share on other sites More sharing options...
Tweedledee Posted October 10, 2018 Share Posted October 10, 2018 What a brilliant project Phil. I'm very envious. They are going to be fantastic to look through. ? Link to comment Share on other sites More sharing options...
BAZ Posted October 10, 2018 Share Posted October 10, 2018 Oh my, that's going to be nice. Following with interest. Link to comment Share on other sites More sharing options...
philjay Posted October 10, 2018 Author Share Posted October 10, 2018 Thanks Pete, Martyn. I have missed scope projects so this is a good one to get back into the swing of things with. Been enjoying messing on the lathe the past few days. I havent looked through Peter Drews rig but knowing the ED80 as great performers singly and Peter saying that they surpassed his expectations plus he can get 200x with them (conditions permitting), I went for it. I will no doubt be sweating when I cut the tubes down by 40-50mm ish (yet to do the sums), I always sweat when doing that, and I must have cut down more than a dozen scopes in my time but it still gets me ? Not decided on collimation of the OTAs, whether to keep the tube rings or do away with them altogether like Peter Drew. Some thought and testing yet on that. Whatever I choose I am keeping it so I can take one tube off for imaging when I get back into it. However I could just stick the guide scope in one tube and the imaging camera in the other oooooh thats a thought ? +Ibbo and tuckstar 2 Link to comment Share on other sites More sharing options...
tuckstar Posted October 10, 2018 Share Posted October 10, 2018 The plan is revealed!!!! Can't wait to have a gander through that when it finished. Looking good. Link to comment Share on other sites More sharing options...
Doc Posted October 10, 2018 Share Posted October 10, 2018 It's a very interesting project Phil, I'm looking forward to the next chapter. What I have learnt from building my mounts is plan, plan and plan again, take your time and get it right first time. Link to comment Share on other sites More sharing options...
+Graham Posted October 10, 2018 Share Posted October 10, 2018 Sounds like a great project. If you need any special bits cut on the water jet just let me know and I'll sort it for you. philjay 1 Link to comment Share on other sites More sharing options...
+Bino-viewer Posted October 11, 2018 Share Posted October 11, 2018 Following this thread with interest Phil. Its looking good so far ! ? I'll be interested in seeing how this design compares to my conventional binoviewer setup with single 140mm refractor / 300mm Newtonian. Link to comment Share on other sites More sharing options...
philjay Posted October 13, 2018 Author Share Posted October 13, 2018 (edited) A little bit done today but not much IPD Prisms sorting some more detail. Made some 2 to 1.25" adapters to fit in the draw tubes that are matched and hold the prisms snug. Ive ran out of M4 long stainless screws so the locking screws will be done later. These prisms need to be snug with no slop otherwise the rig will not stand a chance of being collimated, so all slop is being taken out as much as I dare. An easy job this, swap one dual speed nob to the other side. I will remove the inner nobs and fit blanks to tidy them up and reduce tube clearance What I have noticed is the new scope black sparkly paint isnt as sparkly as my original 3 year old scope, still one cant have everything I spose. Edited October 13, 2018 by philjay Tweedledee, tuckstar and Doc 3 Link to comment Share on other sites More sharing options...
philjay Posted October 13, 2018 Author Share Posted October 13, 2018 (edited) Because there are so many adjustments to get the IPD/eyepiece levels I am making a jig like this one from EZM. Simply adjust the jig to your IPD then adjust the prisms so the jig fits and lock all screws and everything is set in one easy action. These are my bits so far, not as pretty but they are functional. Edited October 13, 2018 by philjay BAZ, Doc and tuckstar 3 Link to comment Share on other sites More sharing options...
+Graham Posted October 17, 2018 Share Posted October 17, 2018 Looking good so far Phil. Keep the updates coming. Link to comment Share on other sites More sharing options...
philjay Posted October 25, 2018 Author Share Posted October 25, 2018 (edited) IT WORKS !!!!!!! ?? Spent an hour or so today on doing a few bits but mainly I wanted to set the OTAs up as a mock up so I can get an idea of how the mounting of the tubes and collimation is going to work plus I wanted to see if I could get bino vision with the tubes just set on a table (mainly to prove it works before I go much further). AND I am pleased to say it works. I set the tubes side by side on the table in the garage pointing out the back door and focussed each on a tree over the way then fiddled to get the IPD whilst looking through the eyepieces and, snap, both images came together and gave 3D binocular vision. Collimation was dead rough but it proves the theory. Here's the mock up of roughly what it will look like, this is with the 90degree prisms in as it will be eventually for astro. Note tubes will be approx 50mm shorter than shown. This is testing for binovision on the trees over the back garden, no 90 degree prisms because focus cannot be achieved with 90 viewing until I chop some of the tubes I think Ive sussed the collimation and mounting arrangement, I am keeping the tubes in the rings and the vixen DT bars will be part of the mounting/collimation sp I am keeping it simple as that makes for a more rigid structure to avoid collimation shift. The tubes will only be cut down at the end when the mounting/collimation arrangement is done so I can test it properly and iron any foibles out with as few prisms in the optical path as possible. I also knocked up a few clamp screws on the lathe. Edited October 25, 2018 by philjay Smithysteve, Tweedledee and tuckstar 3 Link to comment Share on other sites More sharing options...
Doc Posted October 25, 2018 Share Posted October 25, 2018 Impressive Phil, I look forward to checking them out. How are you going to mount them? Link to comment Share on other sites More sharing options...
philjay Posted October 25, 2018 Author Share Posted October 25, 2018 On my extended Giro 11 plus extension all altaz atop the Berlbach Mick. This arrangement is sturdy (I used to put a C11 on it ? ) They will be sitting on a big L bracket I reckon with the tubes on the horizontal arm and the main dovetail bar on the vertical arm. Doc and Bottletopburly 2 Link to comment Share on other sites More sharing options...
Tweedledee Posted October 25, 2018 Share Posted October 25, 2018 Wonderful job Phil. ? Looking forward to a first light report. Link to comment Share on other sites More sharing options...
catman161 Posted November 3, 2018 Share Posted November 3, 2018 This is absolutely awesome Phil! Following ? Link to comment Share on other sites More sharing options...
philjay Posted November 7, 2018 Author Share Posted November 7, 2018 (edited) A bit more done over the past 2 days. The L bracket is now almost there, the basic design has changed a couple of times in order to keep the weight down. My first draft was to keep the dovetail bars and tube rings on both scopes and use them as part of the bracket/collimation mech but this was just too heavy, my second draft still needed some weight taking off so here is the 3rd draft in the rough. There is still a lot of tidying up to do but the general principle is there. The close up shows the 2 yolks (old preformed DT bar) which the cut down tubes will sit on. These will be adjustable for collimation, the inner one for height and the outer for left right. I think once I have proved or disproved this design I may make another more elegant bracket but for the moment this will do. I have thoughts of the bracket being a box design with spring loaded collimation adjusters, we shall see. Bracket with Giro, homebrew extension and Berlebach. Also sorted the IPD prisms and focusers. A couple of lock screws to sort and its all there now. This will give astronomical oriented views as the final diagonals are just mirrored. Once its tested I may put some decent diagonals on it instead of the generics shown. Edited November 7, 2018 by philjay Tweedledee 1 Link to comment Share on other sites More sharing options...
Doc Posted November 7, 2018 Share Posted November 7, 2018 Looking good Phil. The plates look rather thin, I know you are worried about weight but you might induce flex into the mix. Link to comment Share on other sites More sharing options...
philjay Posted November 7, 2018 Author Share Posted November 7, 2018 They are 10mm Mick, I deliberated over this for some time and 12mm would be sturdier but heavier. The 5mm webs will be redesigned to extend further as a web when Ive finished, they were made when I did the mk1 idea so dont extend under the tubes enough now. Link to comment Share on other sites More sharing options...
Doc Posted November 7, 2018 Share Posted November 7, 2018 It's a bit hard to judge scale from a photo, 10mm sounds pretty good especially with longer webs. Link to comment Share on other sites More sharing options...
philjay Posted November 7, 2018 Author Share Posted November 7, 2018 Yeah, due to the angle of the bracket in the photo the horizontal does look thin, but its the same as the vertical which looks thicker. If this works OK I may box in thus strenghening more. Link to comment Share on other sites More sharing options...
Tweedledee Posted November 7, 2018 Share Posted November 7, 2018 What a lovely well thought out job you've made of that. ? Link to comment Share on other sites More sharing options...
Smithysteve Posted November 10, 2018 Share Posted November 10, 2018 Great work! Following this fascinating innovative project with great interest Phil - looking forward to more on same!? Link to comment Share on other sites More sharing options...
philjay Posted November 16, 2018 Author Share Posted November 16, 2018 Some more done over the past couple of days. Collimation adjusters sorted and in place. I have cribbed the cone adjustment idea for vertical adjustment of one tube saddle and the other tube saddle swivels for horizontal alignment. Simple and hopefully effective. I know at least one manufacturer uses this method so there must be something in it. I'm trying to keep everything bijou and compact in order to keep weight down and hopefully Ive got it right. Marking for cutting the tubes, the nerve wracking bit, have I got my sums right? oooer? Tweedledee and BAZ 2 Link to comment Share on other sites More sharing options...
Tweedledee Posted November 16, 2018 Share Posted November 16, 2018 Measure and calculate 5 times and cut once! ? I have faith you'll do it perfectly.? philjay 1 Link to comment Share on other sites More sharing options...
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