ukskies

Thanks Malcolm, it's thanks to your excellent pictorial that i figured out how to get the issue sorted. I thought I had my head around it but I was wrong there. Once the penny dropped I thought OMG I can't believe I got it wrong. Without your posts I would still be wondering so thank you so much again for those posts.👍

Thank you Paz, Kind of you to say. From the views I was getting it was worth figuring it out. I'm already a convert and it's that @mikeDnight that started it, he's to blame! 😆

I can relate to you trying to remember what configuration goes with which scope amidst so many different setups. I can remember when I had a memory but now I need to write stuff down. With all those I'd have to make a spreadsheet! 🤣

Update number 2! 🙈 Yes, I'm stupid, I worked the optical path out to mean I was short of infocus. I wasn't, in fact I didn't have enough outward travel to reach focus and now I fully understand how this works. When I re-read Malcolm's excellent explanations with pictures I realised my mistake. The optical path length of the 2.6x glasspath corrector is quoted as -120mm and the optical path length of the binoviewer is 110mm so in effect they almost cancel each other out bar minus 10mm. If I took both GPC and binoviewer away and used the T-2 zeiss prism diagonal with a normal eyepiece I would require the Tak 2" extension piece (that comes with the DF) attached to the scope before the diagonal. as the Binoviewer and GPC cancel one another out I need the extension with these fitted also! It's so simple I can't believe I got it wrong.🤷‍♂️ Tonight, well before dark the moon was up so I got everything set up in the daylight so I could see exactly what I was doing. I fitted the Tak extension and built and balanced everything on the Vixen mount and with the Moon in the finder crosshairs powered up the mount. The binoviewer was on with the 2.6 GPC in the diagonal and the two Baader Mk IV zooms in the holders. I adjusted the inter pupillary distance to close enough. Then I looked in the eyepieces with the zooms both set on 24mm. Pale cream light filled the view as I turned the More Blue coarse focuser and suddenly I saw detail appear and disappear! Ha I was close!! On to the fine focus wheel and back in slowly, suddenly the Moon was in super sharp focus sat in a blue sky surround and lacked the contrast a dark sky provides but it was sharp and detailed nonetheless. I then viewed for a while trying different magnifications on the zooms and at all settings when I tweaked the focus the Moon was pin sharp and the view was very comfortable and looked amazing. I had left the T-2 ring that holds the Binos to the diagonal very slightly loose so I could turn them in relation to the diagonal and thus get the angle right for my eyes. This I struggled with on my previous update as it was too tight. Tonight it was free of play but did allow rotation of the unit and was easy to do. As the view was quite steady I popped in the two 5mm BST's for nearly 400X and not expecting much I was surprised when the focus snapped in. The Copernicus crater was sharp with very detailed crater walls. The shadows weren't black and the usual contrast was lacking but it was still an hour before sundown and the view was very sharp. I was elated, the small 0.26mm exit pupils were very comfortable to view with and I'm sure I've not seen as much variance in shades on the Lunar surface as I was noticing tonight. Work tomorrow so I pulled the scope in early and I won't be out again until Thursday evening if the clouds stay away but if so I will wait for full dark. In conclusion I'm very pleased with this setup now and a huge thank you to all who contributed to this thread and helped convince me to get the Bino's they are brilliant.

Hi again everyone, a quick update. The 2.6x GPC held things up a bit but I told FLO that i would wait for it to arrive and they could send the (second) zoom and another BST 5mm all together. In the meantime I fitted the More Blue 12 to 1 MEF unit and removed the helical focuser and screwed the Binos straight onto the T2 diagonal, the Maxbright case is designed to hold the viewers and T2 diagonal whilst attached. This meant that I couldn't do much with the binoviewer except cover it to keep the drool off until my second delivery arrived. Well it arrived on Wednesday. Working Thursday meant no late night Wednesday so I decided to wait until Thursday (last) night for a play hoping the clouds would give me a break. Thursday evening, Luna was up way before dark so I thought this ideal for my first play with the Maxbright as I would be able to see what I was doing. Got the frac out on the old vixen mount, pointed it at the Lunar terminator and powered up the drives.. This meant i wouldn't be far off the target once I was ready to view. I have a 2" nosepiece on the T2 and this went into the Tak 2" tube adapter so no loss of inward focus travel. I then popped in the 2.6 GPC and slid the scope forward almost all the way through the clamshell, added the two zooms and checked the balance. It was close but very slightly back end heavy though not by much so I figured the motors would cope with it and they did. Next it got frustrating! Both zooms set on 24 and I could not reach focus. With the focuser wound fully in there was simply not enough inward travel to reach focus. Checked the Maxbright manual and yes I've got the GPC in as shown facing into the diagonal but it wouldn't quite reach focus. out comes the GPC and yes the zooms just reached focus but the focuser was racked out only a half mm I'd guess. I tried the zooms at various settings but at the 8mm setting I could not achieve focus. Finally I tried the two 5mm BST's. Focus was achieved with less than 2mm of outward travel but I was now able to set the diopters for the sharpest image in both eyepieces. I decided to spend some time viewing now as it was getting dark and I had the moon up and visible though bits of cloud were now interfering (normal service) so I had 148X mag in both eyes for the first time and I attempted to be subjective about the view. The seeing from my town garden looking west over a block paved area that's six feet above scope level and with houses behind that after a very sunny day was not the best, Luna was constantly rippling in the unsteady air. There was however something about the Bino viewing that I liked, It was certainly very comfortable and relaxing compared to the Cyclops view I'm used to. It wasn't simple, change of target now had the added issue of getting the two eyepieces into a position where I could see an image in both, never mind seeing the full field. Unlocking the T2 ring to re adjust the angle often resulted in me altering my carefully set inter pupillary distance and the angle I found was quite critical at this (148X) magnification as I only had a 0.68mm exit pupil and two pupils to line up. I fiddled and cursed and cursed and fiddled but eventually went back to Luna at 148X and just drank in the view. There was definitely something to this new crazy, extremely expensive experiment. The positives are viewing comfort, once correctly positioned it is just so relaxing on the eyes. this is a huge plus. The view I think was a bit more detailed and dimmer by a small margin but with a target like the moon dimmer is a positive and more detailed is always a positive. The conditions were not conducive to drawing any meaningful conclusions and I was denied any higher powered viewing and subsequent smaller exit pupils by the lack of focus travel though the seeing would not have allowed more anyway. The negatives well we won't mention cost so I think the issue is keeping two small exit pupils in line with your own pupils whilst pointing the scope at various different bit of sky is 🤔 ...challenging. It may get simpler with practice and I may be doing things wrong so far but I'm pretty sure the EQ mount, Binoviewer and me are not a marriage made in heaven and unless one of you kind people can tell me a better way I'm thinking the Vixen EQ will have to go. an Alt Az mount would make things so much more straightforward in operation. I also have the lack of infocus issue to get around too and maybe I can swap out the 2" Tak adapter for a Baader Clicklock and gain a few mm more, maybe I should change the nosepiece to a 1 1/4" one and put the GPC before the diagonal. Any ideas anyone? I'm waffling so all the best and clear skies. EDIT: I've just revisited Malcolm's pictures and detailed description and from Baader specs for the 2.6 GPC it looks like I may need an extension for more back focus and not infocus as I thought. I'll report back after trying this.

Just a quick update. First, many thanks to all of you for your helpful contributions to this thread, you helped me decide. I now have in my possession one Maxbright mk II binoviewer and I have ordered another Baader mkIV zoom (I already own one) and a 2.6 glasspath corrector which will be delivered when the GPC comes into stock, this should be within two weeks. I feel that having the zooms will give me a great magnification spread whilst I'm experimenting to find what works best for me and offers a low cost option too. I can change the adjustable eye cups with the plain rubber ones that come with the zooms.this will give me another 10mm of additional clearance for my nose and about 18mm space altogether.

Maxbright II is inbound. Whilst posting and reading this thread I was keeping a close eye on FLOs stock levels and suddenly last night it was on 1 so impulsively I ordered it! 🤣

Thanks Paz, this is more excellent info and a big help.

Many thanks Mike, that's more great info, are you still using the helical focuser with this setup too? I've got one on my T-2 prism and like it for mono viewing, it's just so smooth and it seems more intuitive to find in the dark too. i

Malcolm, thank you for posting these detailed pics they are brilliant and a great help. I now understand it all. It really helps that we have the same scope plus I want the Clicklocks too. A picture is worth a thousand words eh?

That's going to be an interesting comparison then, please update us later with how that works out.

It's a dark art Rob.🤣 Thanks, I think I'm gradually beginning to understand the mechanics of it and thanks again for all the help. The back focus measurements will be especially helpful.

Mike when you say Barlow do you mean a conventional Barlow or a more specialised one, like this William Optics one for example? https://www.firstlightoptics.com/binoviewers/william-optics-binoviewer-2x-barlow.html

Just looking at your setup picture and wondering so I thought I'd just ask instead. 😆 When you are in focus on the above setup how much of the drawtube is extended? No need to measure Malcolm just approximate please if you can, it would help me understand the back focus a bit.

Not a problem Rob we're all human. It was nice of you to take the time to post and thanks anyway for clearing that up. I agree with you that it is all a bit confusing though but then all power to Baader for their excellent work.

It is a nice set of troubles you have there though Malcolm that's for sure. I can't see adding an ext-Q is going to make you many more.😉

Thanks Malcolm, I've downloaded the manual now and it's very infomative. Sounds like you need an Extender Q then too. 😉

Hi Malcolm, thanks for that. I'm a big fan of clicklocks and fancy a setup similar to yours with a 2" clicklock on the drawtube. My T2 prism has a 2" nosepiece to go direct into the clicklock so no reducer would be needed at that position. Should give a very central alignment and positive connection. Only thing that may upset my plans is the 1,6x Ext-Q as this is supposed to fit there somewhere too. Just for clarity are you inserting the 1.25 GPC in front of the diagonal?

That's how I imagined myself using them Stu tbh just for the higher powered stuff to beat the floaters but this thread has me thinking now so once I have a binoviewer it would be a shame not to experiment. Thanks for your good wishes.

I was looking at the 2" version of EXT Q to fit in the 2" drawtube? it's this one. https://www.firstlightoptics.com/takahashi-extenders/takahashi-ex-q-16x-for-fsq-106ed.html

Thanks again everyone, your posts are both interesting and informative, it's a big help.

Thanks again Rob, and Mike. Mike your post has now made me think about the magnifying effect of Barlows which I wasn't considering. A 2x Barlow giving nearly 4x magnification? No wonder so many people are using 20mm eyepieces for planetary with binoviewers, I was aware that putting a Barlow in front of the diagonal say will mean greater mag than when it's close to the eyepiece but the penny hadn't dropped, DOH!🤦‍♂️ That brings up another question now. I'd imagine that the glasspath correctors operate at the stated magnification as they are designed for the binoviewer but I'm wondering now if this is actually the case? I'm also considering a future purchase of an Extender Q which is 1.6x and sits in the drawtube in front of the diagonal, I'm wondering now how this will magnify the image through a binoviewer? Is there a formula for calculating this magnifying effect does anyone know?

Thank you all for your detailed replies so far. You have pre empted my main concern with the mkIV zoom, and that is it's diameter. The eyecups are large, 55mm diameter I think, and I think my inter pupillary distance is 62mm leaving only 7mm gap for my nose. I just thought it would be something worth trying as I do like the ability of the zoom to adjust to the variable seeing I get quite often. You have also alleviated my concern about the prism diagonal. I fitted it with a helical focuser to help at higher powers and before I fitted it I remember the prism being very close and didn't think there would be room for a GPC without hitting the prism. Rob, I think those APM flat fields are the same eyepice as the FLO Stella Lyra UFF's? If so I was considering pairs of those for Lunar and planetary. I already have the 30mm which is a very impressive piece of glass. Finally I had only really thought of Lunar and planetary for the binoviewer but is it also good for brighter deep sky objects too?

Hi all, after reading several members posts on the benefits of Binoviewers I'm thinking of getting one of these to complement my 100mm frac mainly for Lunar and planetary use. I do like the Baader stuff as it is good quality so I immediately looked at these even though there are less expensive options. The scope is very sharp and I don't wish to compromise the higher powered views. Although it is primarily for the FC100 there is no reason to not use it on my other scopes too. I know many of you have Binoviewers and I'm hoping that you will convince me one way or the other as to the best accessories to enhance my viewing. I have a few questions that I would like to ask. 1. I believe many use Barlows and longer focal length eyepieces so do any of you use the Baader glasspath correctors or just generic Barlows. do you use cheap or more premium eyepieces? 2. I already have a Baader mkIV 8-24 zoom and could easily pick up a second for bino use, any thoughts on this? 3. As the bino itself is over £400 I do need to carefully consider what accessories I buy to go with it so are there any good but less expensive options that you can recommend. 4. How firm is the diopter adjustment on these? Baader suggest the mkIV zoom to be a good pairing but I'm concerned that rotating the zoom ring might disturb the diopter setting. 5. I have a T2 prism diagonal and I believe the viewer will couple directly to this. Does anyone know if the glasspath correctors would still work in this arrangement?

I am reading this thread with interest. I have never actually noticed any "colour" on the moon but I have never really looked for any, many different shades but colours no. I have noticed that my eyes are very sensitive to false colour so hopefully they will be sensitive to the subtle colours you skilled observers are referring to. I'm going to have to look for this now.