keith5700

MrH, the control box now will only control IPD and diopter setting. I’ve deleted the pre-settable focus idea because of the previous mentioned problem. I’ve had binoscopes for over 20 years, and I like to show other people the views, but I sometimes struggle to explain what they need to do to adjust the eyepieces to suit them. I’m talking about people who have probably never looked through a telescope in their lives. The eyepiece width setting is self explanatory, but can be tricky to do when the field of view is mainly dark. Diopter can be a bit harder to achieve. In my previous scopes, I’ve had a servo which moves one lens, or mirror, closer to the ep, and moves the other further away. The idea being that you adjust this setting until you have an identical diameter out of focus disc, from a star or planet, and then you can use main focus to get the image sharp. But that has been hard for some people to do, so this time I’m having the right hand lens as my datum focus, and then the diopter will just alter the left hand lens, just like most normal binocs. Yes it will have GOTO and tracking. Price wise, I’m keeping a tally, but not dared look at it yet. I’m hoping to keep under £3k, which should be ok, as I already have all the eyepieces and the tripod/stand. And I’m aware I could have just strapped a couple of telescopes together and used some prisms and mirrors, or amici prisms, to get to the eyepieces, but I didn’t want to restrict the light quantity or the light cone in any way, so I’ve just got a lens and a big mirror in each path, so I’m happy I’ve got the most light possible from each lens. cheers.

Update time. It’s still a complex project, but that’s what my hobby is. After years of keeping things simple at work, it’s nice to get home and do some unrestricted engineering. I might scrap the focus motor idea though. It works ok, but then there’s some subsequent creeping of the motor, because the 10 turn pot isn’t accurate enough. A stepper motor upgrade may be the way for the future. I’m using toothed belt drives for both axes. I’ve used them hundreds of times at work and home, and this one works fine, as in almost imperceptible play and flex, because the free lengths are very short. im trying to borrow a set of rollers to roll the ally sheet to make the main tube, but no luck yet. Need to start drawing up the Az drive next. This will be similar to the Alt drive, but the clutch system will need a rethink, so the lever is out of the way.

Latest pics. Hope the telescope is visible amongst all the crap. Thought I’d photograph it before all the black anodising and painting. The RH eyepiece is static, the LH one does the sliding for the eyewidth. The complicated bit is keeping the LH objective in line with the eyepiece. So the bevel gears turn a shaft which goes to the front lens, which goes through another bevel gear set, which moves the objective. Dont mind saying though, I screwed up a little. When the eyepiece moves right the objective moves left! Didn’t think about that. Just need a left hand thread M12 tap and die to sort that out. The over complicated mirror holders are so that when setting these, any movement in either plane won’t alter the centreline position, ie. the rotation and pivot centre will always be exactly in the centre of the mirror. It’s a lot more work, but pays off when it comes to collimation time.

MrH, everything in the photo comes to 5kg. The lenses weigh 5kg together. I was hoping to keep below 15kg total but with the lenses being heavier than anticipated I think it will be a bit more. Chriske, this is my 4th binoscope. I have a 400mm reflector bino I tried to sell, but no interest. I’ve stripped it and am trying to sell the parts. I just want something a bit quicker to drag out of the shed and setup these days. Using just one eye for viewing gives me a right headache after 10 minutes or so, even if I keep the other eye open.

Thanks Mark. Yes, Nilfisk vacuum, best thing ever! MrH, hopefully latest pics are a bit clearer. The mitre gear turns an M10 threaded and keywayed shaft, which moves the objective sideways. A shaft runs through the 3” ally tube and will turn a similar setup for the eyepiece holder that side. The main focus gearmotor/ballscrew will push the objective that side, and the other objective will be also connected to this, but with the little servo in between. This servo will turn some sort of thread so this objective can move slightly relative to the other one. This will give the diopter setting. So, these will be the 3 variable settings. I haven’t thought too much about the initial collimation, but from my previous binoscopes, it will centre around getting the shafts which everything slides on to be perfectly parallel, or coaxial, to the theoretical centreline of the scope. last time I used a long water tube level, and a laser, which datums off the sliding bars, and projects on a target at the other end of the shed. I’ll know more when I think about it properly. im just waiting for my belts and pulleys to turn up, so I can try the mechanisms.

Thanks. My main focus will be by moving both objectives together with one servo motor. The diopter adjustment will be with a second small servo which will move one objective forwards, and the other one backwards, in equal amounts. Then there’s the third motor moving one eyepiece holder and objective left or right, for the eye width. The other eyepiece remains in a fixed position at all times.

And after a couple of weeks this is how far I’ve got

I won’t bore everyone by showing how I made every single part, but this is a typical part. Loads of hogging out on the lathe, over to the milling machine, finish off by hand, in the anodising tank, into the dyeing tank, then seal the dye in.

After living with my 400mm binoscope for years, I’ve decided to build something a bit more practical. I just want to drag something out of the shed, have a look around for half an hour, and then push it back in. So I’ve decided on a 150mm refractor bino. It’s still a binoscope, I’ve tried using just one eye but find it horrible. I’m going for the under and over design, so there’s only one optical flat in each side. I like to over complicate things, so I’m making all the variables, eyewidth, diopter and focus, move by servos. This means I can store the settings for swapping users, or eyepieces. The most difficult bit is that to alter the eyewidth I need to move the eyepiece holder and the objective lens together, but I’ve solved it by having a driveshaft between the 2 and some 90 degree bevel gears. Hopefully all will become clearer as I progress, but here’s my basic layout.

I reckon I win this one. I’ve given up being tidy, just get the job done. Too many hobbies!

I bought a couple of the scopes in the end. Lens is 31.6mm at the edge, if anyone ever needs to know. I have another question though. I measures the internal baffles to see what the designers were thinking as to the light cone. ie what diameter of light hits the eyepiece. I was thinking at least 15mm dia. drawing it all out, in a straight line, shows it has a 5mm dia light cone when it hits a 17.5mm Baader Morpheus, for example. Surely this isn’t big enough, or am I missing something?

Wow, that’s a beast.

Thanks. I contacted them earlier in the week, but no reply yet.

Thanks. No, the only thing I need from the scopes is the objective lenses. Don’t even need the lens cells. Shame to waste the rest, but highly doubt I could just buy the lenses from anywhere.

I’m just designing my next binoscope, and can start buying stuff if/when I sell my 16” reflector binoscope. I’m going to make a smaller setup, with 2 x 150mm f5 refractor lenses from Startravel scopes. All I need at present is a couple of dimensions. Does anyone know the thickness of the 6” doublet lens, at the edge? Just so I can order the material to make the bespoke lens cells. Also, the 750mm focal length? Where is that dimension taken from? Is it from the rear of the lens, or the midpoint, or the front? Thanks.

Ok. I emailed Romer with a similar question, and just had a reply from Eric. they no longer sell the kits in pieces, where you have to buy certain parts to finish. They will in future be sold as complete systems. But they will not post to UK, due to future service problems, so not much use anyway.

Frank, how did you work out all the bits you needed, etc? I’ve been on their website to try and price up everything I’d need, but it looks a right mess. did you buy the basic Goto kit and this came with all the instructions of what else is required, and how to wire it all up? Or is there a page on their site somewhere that I’ve missed, which explains it all clearly? thanks.

Well, it’s up for sale on the Astrobuysell site. I’ve put it up for £4750. No takers yet, but been offered a couple of interesting swaps. Itching to get started on the next one.

Yes, tertiary flats, similar set up as on my current scope. Hoping it will be a bit easier as I won’t be standing in the light path.

Yes, all valid points. There’s no getting around the field of view reduction, so I’ll have to think if I can live with it. I’ve not done much work on a design yet, but I was thinking of spacing the tubes apart and bringing the light cone out the side of the tube.

No I hadn’t. Thanks, it was very interesting.

Yes, I fear you may be correct.

Well, the initial setup took around 2 days. We had lasers and plumb lines and all sorts of stuff in the workshop, but that was because as well as being collimated individually, and as a pair, it also had to be aligned axially to the central tube, as the main mirrors travel up and down the tube, for focussing. After that however, I’ve hardly had to touch it. It’s pretty much exactly as I set it initially, presumably because it’s all rigid with no slop anywhere, and it all assembles repeatably on dowel pins, etc.

If I get enough money for this I’d like to make something a bit more compact, or easier to set up. Still a binoscope, but with something like 2 x Celestron C11’s. I’ve still got to do some sums to see if it would be worth just selling the optics from this, because there’s a load of stuff on this scope that I’d have to buy again for the new one.

Thank you, I’ll take a look.