dweller25

@Olli Of the scopes you talk about I would agree with others, a 4” refractor would give a meaningful improvement over your current scope. Takahashi’s are nice and have great optics but I would suggest you read this, which is very accurate……

Superb images 👍

Superb images @Eris 👍

Lovely scope - enjoy 👍

Hmmmm, priced between the Skywatcher 180 pro and the Mewlon 180. Take your pick …… Or should that be pick your Tak 🤣

I decided to add a RACI finder to my Mewlon a few years ago necessitating back plate removal. So it needed a slight tweak when I put it all back together. It has held perfect collimation ever since after a lot of “in’s and out’s” An American astronomer - Ed Ting found his Mewlon would not hold collimation but I strongly suspect the locking collar for the primary just needed snugging up. In my opinion they are very solidly made scopes.

@HizerKite just noticed a slight collimation offset - see the two spider vanes I have highlighted in red below. It may be worth checking the length of those two vanes - although it will not stop you getting perfect optical collimation. Although it could also be an alignment issue with your camera position.

I also use the “hall of mirrors” procedure during the day to collimate my Mewlon, I find it’s good for 95% collimation, with SLIGHT tweaks being needed at x300 on a perfectly focussed star. BUT - the mirrors must be fully cooled first - I use active cooling. First I take off the front and rear caps, then rest a USB powered 50mm PC fan on the front spider for an hour - it works nicely. Your “hall of mirrors” looks close 👍

I was out at the same time, that image is good considering the poor seeing 👍

Would that be a Tackahashi sewing machine ?

Astronomy in the UK does seem to require a slow patient approach due to the weather. I have reduced the herd to just two scopes now, a 4” APO and a 7” Mewlon, both are well suited to a light Vixen GP mount which means I can get out quickly with the 4” if the weather clears up. If the weather is more stable then the Mewlon comes out - It’s a really good scope. I need to move away from wet and cloudy Lancashire though……..

And if it looks like this then your scope needs collimating to get sharp images….

@mirrorgirl1980 If possible leave your scope outside for an hour to let it cool down. Then check a slightly out of focus star at x200 a star should look like this with the circles all concentric around the central dot…..

I use TV Plossls down to 20mm, I tried the 15mm’s but the eye relief was too small when wearing glasses.

@mirrorgirl1980 Your Jupiter image is a little blurry. How do you thermally acclimate your scope ? And how does collimation look at x200 at perfect focus ?

My last Windows update turned it into Win-doze, the computer ran really slowly. Have now done a full OS install and it runs really fast 🙂

Nice image despite the conditions 👍 I was out too, enjoying a really clear sky when a sudden strong gust of wind arrived, followed 10 seconds later by heavy rain, everything got wet in the dash to get it all back indoors. Lancashire, Hey ho 🤷🏻

That’s a very accurate observation Jim 👍 Don’t mean to rub the salt in but I have just been observing the Cassini division in a 180mm reflector at x188 - albeit only at the extreme edges of the rings and I was using binoviewers which really helps. I tried earlier but Saturn was too low and the scope was not fully cooled. It’s always a great sight though 🙂

I would choose the 80ED as it will give the purer unobstructed view and will cool quicker 👍

I would also suggest enquiring on Cloudy Nights 👍

I wear varifocals when observing and have found 15mm eye relief to be the lowest I can go (18mm Orthos), around 20mm eye relief I find is more comfortable.

I believe the 8”CC has an working aperture of around 7” so moving to a C9.25 should give improvement and a C11 even more, but they seem to out of stock at the moment. But if dew prevention comes into the equation then the 10” CC may be a good choice - but it’s 17Kgs ! Another option could be the Mewlon 210, no corrector and 1/20th wave optics, but it’s expensive. No easy answer 🤷🏻

Nice scope 👍

I think the image is a SkySafari simulation

Great image 👍