dweller25

Hello, Hope this is the right place to post this question ? I have an old 1.25x Baader GPC that has no sticker on the side to tell me if it needs mounting in the MK V binoviewer or the Baader Zeiss Prism housing. I just took out the lens and did this drawing of the cemented doublet. How should it be mounted in my setup ?

Been there, done that - the answer is visually “no” , weight wise “yes”

Congratulations 🥳

The symbol indicates that the dollars in your bank balance will reduce

Yes, I watched it too, a nice eclipse watch and the GRS visible too 🙂

The Fluorite lens is placed at the front to give that prescription better performance. I think all the 5” FS128’s had this arrangements, but other sizes had different setups. There are rumours that as the Fluorite element is at the front it will absorb moisture over time and degrade. Natural Fluorite is very slightly hydroscopic. However the lens in the FS is a synthetically grown crystal that is very hard and not hydroscopic. My FS128 was manufactured in 1998 and still performed superbly, the rumours about the lenses degrading/softening/dissolving is nonsense. There is also a rumour that a cold Fluorite lens will crack if taken into a warm room ! You can buy in confidence, there are even older Fluorite scopes still around that have not melted 🤣 PS - The tennis balls were to protect my wifes ankle after she had surgery 👍

As a visual observer a bright but not sharp image would not work for me. Best solution is a bright and sharp image 👍

Thanks for the heads up 👍

When you take a warm SCT/Mak outside on a cold night it will have internal thermal temperature differences between the warm mirror and the cooling aluminium tube assembly which is exposed to the cold air. This causes turbulence at the eyepiece. One way to deal with this is to leave the scope outside for a couple of hours so the mirror cools to the same temperature as the outside air, in other words there is no thermal gradient between the mirror and outside air. Another way to deal with the thermal gradient is to wrap the OTA with two layers of Reflectix which you can get from B&Q, this allows you to use your scope straight out of the door.

The video does suggest the Tak is better but it was used an hour after the 125ED so Jupiter would have been higher and possibly the seeing was better.

Good point John and the 125mm doublets have been compared by a couple of reviewers to the FS128, with the FS just having the edge in both reviews.

Yes, WO are a bit naughty there, but it’s basically a 126mm version of your FPL53 TSA But the FS is true Fluorite and 2mm bigger 👍😈🤣

FPL53 synthetic fluorite - they have covered all options 🙂

@JeremyS is lurking here but staying quiet as he only has a TSA120 🤣🤣🤣

I think the WO Z126 is FPL53 not fluorite ?

Trust me the FS will make the TSA redundant 🙂

PS - I replaced the TSA with a FC100-DZ and it’s just as good 🙂

I have no knowledge of the WO Z126 but I had a TSA102 and FS128 at the same time for over 10 years. I used the TSA on a Vixen GP, the FS128 NEEDED a Vixen GPDX and a Berlebach tripod, so it’s a heavier setup. The views through the FS128 beat those through the TSA on all objects and the colour vibrancy in the FS128 was excellent. I would totally, unreservedly and enthusiastically recommend the FS if you are OK with the higher weight setup.

Oops I have been calling projections “festoons” for years ! Thanks for sharing

As Geof says 👍 Also have you aligned the finder scope to the eyepiece view ?

@phantomgod_06 I think you are using a 127mm Newtonian with a focal length of 1000mm ? If so your scope should be showing the major bands on Jupiter. For best results your scope must be :- Fully cooled down Well collimated Well focused You need a power of at least x100 which the supplied 10mm will give but it is not a great eyepiece and you may want to think about upgrading it. X160 would be a better magnification which is a 6mm eyepiece like this…. https://www.firstlightoptics.com/stellalyra-eyepieces/stellalyra-6mm-125-ler-planetary-eyepiece.html For best results you should observe planets when they are as high in the sky as possible which is when they are due south in the UK. Light pollution does not have a big effect on the planets. Hope that helps

Nice scope, great pooch 🙂

I am amazed you don’t have one 😈

@fireballxl5 that is briiliant, I was out at the same time trying to see it visually but could only see the shadow. Well done and thanks for sharing 👍

That’s a good start @FlaviusYNP 🤣, welcome to SGL 🙂