PeterW

Ah, you have a time machine....? peter

Looks like they were made that way, sounds like great service. Peter

I do still wonder what level of tube coupled with a fast low power lens and a long pass filter could be used for outreach to show people the Milky Way… Wouldn’t need such high specs as we need for nebulae…. The public (even astro imagers) don’t get impressed by nebulae that much but get shocked by the abundance of stars that appear. Could be an Echo could work for this?? Of course if you want to dig up really diffuse nebulae you need all the gain and contrast you can get, which still costs more. Peter

The request was for non-NV. NV being real-time doesn’t care what mount you use. For faint stuff I find it an advantage to have a manual mount as you can pan around and let peripheral vision help pick things up. Of course then you have to do the finding, which can be hard as NV shows stars different apparent brightnesses, so goto can be a help. As noted for whatever EEVA you want to do, decide what sort of field of view you want for the sorts of things you want to observe and then find the fastest optic to give you the focal length you need for the sensor you use. It might be that you need more than one system for large nebulae and small globulars and galaxies. peter

Using a camera will need a tracking mount so that the longer exposures can be built up. There are tracking platforms that you can pop a dobsonian on and it will track for a while, would allow you to make use of the aperture. You’d need to look out for reviews and what accuracy they could give you. peter

Lots of citrus, hot up a bit late. But lots of detail in the active region with 80mm and binoviewing, switched to hydrogen alpha, nice, but not quite as detailed. good to have sunspots back! Peter

Nice views of the Milky Way with a 16mm focal length lens... different things need different optics to observe.... Peter

With a fixed lens you can still use a 3x lens though no ultrawide or slightly higher power options that camera lenses would enable. It is easy to make or buy (depending on threads) a 2”filter to the 1x or 3x options. For maximal focal reduction afocal is probably the best option, though it does lead to rather a long unit in the focusser. Many commercial tubes have occasional black spots, there are specs that limit the size, location and number. I have a little spot off to one side, doesn’t bother me. I agree that the photonis gen2 are behind the Gen3 even for the best specs. Peter

You definitely want some insulating cover to the metal, especially at night! Using some thin card ought to get a Pattern? I have covered the metal bits of a monopod head with few mm thick neoprene rubber sheet, though not sure how this would work for binocukars. Peter

The Photonis uses a different photocathode to the harder, Gav has compared and the harder Gen3 is the way to go. I thought the photonis cost more than the harder for similar FOM? There are secondhand options for Gen3, which will cost a good deal less, but then you don’t know what the specs are, though thewy should still work plenty well. Don’t be tempted to go for Gen2/2+ as they won’t perform as well. Peter

Show off! More better, but lower spec stuff will still show plenty. mark, the epsilon instructions may be have to read as they might be a bad translation... Japanese commonly makes for hilarious or incomprehensible translations. If the views are ok then leave the little screws alone! Peter

As long as the newt is reasonably well made it is easy to collimate with a laser, NV is low power so slight errors won’t show. Peter

The BorenSimon is just an f5 newt with a special reducer-corrector in it. I use an f4 imaging newtonian and a 0.5x reducer and run around f2.5.... cheeeper still. tue 67mm afocal reduction turns any reasonably quick system into a decent NV system. (Mike Lockwood has shown this still works if you star with an f3 system!) I wouldn’t fret about trying to have a “perfect system”, there are many good options, start with what you have. Check SGL or CN to see if anyone has tried specific things before. @Highburymarkyou’ve been lucky on your trips, I’ve seen crap skies in dark locations before. Always best to have a few “test nebulae”, see what they look like, then you know if it’s a special night to go after the really challenging stuff. Peter

You could have used a 3d printed former to help the bending and drilling.... plenty useful for jigs and fixtures too... nice rig! Peter

Refractor questions go to Gav... but when you use the 55mm plossl for afocal it doesn’t shift the focal position much, whereas adding a focal reducer pulls the focal position inwards. My “imaging newtonian” needs an extension to use normal ep, but focuses nicely without when I use my “0.5x” reducer in prime focus mode. F8 is slow for a scope to do NV with, best start faster as the 67mm Televue will speed stuff up 2.5x and you want to get down to around f2... or faster. The f4/f5 carbon fibre tubed newtonians would be better, start faster and can be sped up nicely, you can add a coma corrector if you feel it needs it (I don’t with mine, but with a normal wide eyepiece I do). again all we are doing is finding a way to get a certain field of view (focal length) as bright as we can (fastest focal ratio). Peter

Pretty good “stack” in the focusser Mark, good thing you’re using an alt-as or the eyepiece could end up anywhere ;-)!! Peter

Think focal length! You need to get things fast, so using the TV 67mm afocal giving nearly 2.5x faster than native. I don’t try ink you need excess infocus for this @GavStar can confirm. Fast gives a brighter view. What you them see is determined by the effective focal length you have. So fast and big gives the same image scale as small and slow. Massive scopes just gives smaller fields of view, better suited to smaller objects. So ideally you will have several scope options with different focal lengths that you move your “eyepiece” between. Get over the aperture fever..... my last NV optic has a 16mm focal length! Peter

OK, just spent half an hour in the garden testing the gloves out (also with muck boots, “marshmallow trousers”, an M&S trapper hat and the wife’s new winter coat). 9C and a breeze, so nothing especially challenging, but couldn’t tell it was cold at all apart from the tip of my nose. So the new Black Diamond Mercury Mitts have finally ended the days of cold hands. Now to keep my nose warm.... I just need to get my own jacket. Peter

It’s all a case of what focal length you want and the speed you can get to. Flat field and fast is good as is 2”’focusser so you can use the Televue 67mm plossl afocal unit to speed things up good and proper. peter

“Marshmallow” trousers and muck boots for part of it. Peter

Just picked up some lines mittens, if my hands still get cold I’m quitting observing till the spring... got some cold nights soon to see if they deliver. Peter

No chance! EEVA is no better than surfing the Internet, and processing images is just artistry (unless you’re looking for novae/comets etc and doing science). I went for NV as large reflectors don’t fit my life style, so I have committed to an outdoor life. I have the feet sorted, the head, recently *sorted* trousers, now hopefully the hands... I can layer up a coat, but might go downfilled..... if Boris let’s me go try one on to sort the sizing. Peter

Right.... if I *still* have cold hands now I’ve got these then I am quitting this hobby for something I can do in front of a warm fire!! I’ve bought plenty of gloves over the years and they’ve never worked ideally, so with some cold nights soon we’ll have to see how these cope...... fingers crossed 😉 Peter

The main visible colour is green, though there are reds which NV would be better suited to see. I’d have a look at the emission lines that predominate in aurorae and whether you've got any filters that sort of help remove other colours and give it a shot. Looks like a 600nm long pass would help? https://www.windows2universe.org/earth/Magnetosphere/tour/tour_earth_magnetosphere_09.html Though you’d want to be away from the worst of city light pollution and you’d want to work a 1x or 3x to have a nice big field of view to see any structure more clearly. Peter

Moderate speed refractor and the 55mm Plossl afocal (now with a 67mm extra adapter). I use an 80mm f4 jumbo finder with a little extra reduction prime focus, handheld, so you can swing it about to find stuff. Play with field of view calculators so you can get an estimate Of what you’ll see. Focal length sets the field of view, speed the brightness. small scopes are good for viewing the big stuff, the opposite of your big dob. peter