Meade Infinity 102

[Ray of LIght]

1 hour ago, Mak the Night said:

I have an account at FLO, 200 quid doesn't seem like a bad price for a Zarkov. I'd probably have to fire it left handed though, so it could be a bit dangerous. I'm not too keen on the steampunk look either. Plus, Bakelite handles tend to shatter in the cold. Luckily, I don't drink a great deal of rainwater. lol

I feel my leg being pulled?! I know your not into the solar stuff but I have decided to buy a solar filter instead of DIY. It is sold by Gosky but it is all Baader: Astro Solar Filter and cell mount. I can use the solar film to shield my Quickfinder, so it will still have a use. It has a 127mm clear aperture and with three adjusting screws will fit dew shields between 127 and 154mm. So instead of fiddleing around I will have a safe Baader filter. I hope I will find a little solar observing interesting. How is the weather? Will be pants here next couple of days so I won't be missing much I guess. Back in a bit.

[Mak the Night]

I should imagine it would be safer than the DIY approach. You'll be surprised what else FLO sell!

[Ray of LIght]

1 hour ago, Mak the Night said:

I should imagine it would be safer than the DIY approach. You'll be surprised what else FLO sell!

That's the main reason I went with the Baader solar equipment all ready to go. Yep, that is some company that FLO, lol!

[Mak the Night]

34 minutes ago, Ray of LIght said:

That's the main reason I went with the Baader solar equipment all ready to go. Yep, that is some company that FLO, lol!

You can't really go wrong with Baader equipment. I reckon you'd need some huge counterweights for the Hubble on an EQ mount!

[Ray of LIght]

9 hours ago, Mak the Night said:

You can't really go wrong with Baader equipment. I reckon you'd need some huge counterweights for the Hubble on an EQ mount!

Lol ?!

[Ray of LIght]

Well Mak, I ordered the Baader Solar Filter and received the 3.2mm Starguider. Haven't opened package yet. I believe they are color coded: the 3.2 has purple rings, my 8mm has orange, not sure you could tell at night but it also has the FL and ED printed on them. Extra Low Dispersion? Not sure but I read that is good glass?

[Mak the Night]

39 minutes ago, Ray of LIght said:

Well Mak, I ordered the Baader Solar Filter and received the 3.2mm Starguider. Haven't opened package yet. I believe they are color coded: the 3.2 has purple rings, my 8mm has orange, not sure you could tell at night but it also has the FL and ED printed on them. Extra Low Dispersion? Not sure but I read that is good glass?

I think ED glass has something to do with the qualities of anomalous partial dispersion (I’m not exactly sure what that is lol). Apparently it also has a low index of refraction and the focal lengths of individual ED glass lenses can change slightly with temperature because it is less stable than conventional glass or something (kryptonite based? lol). ED glass can remedy a lot of fringing I think. I'm fairly sure FL refers to fluorophosphate glass which is used to make a lot of extra-low-dispersion (ED) lens glass. Before that lanthanum oxide was used I think. Vixen used to advertise EP's as 'lanthanum glass' and I've got a funny feeling TeleVue Radians were made with lanthanum. The cynic in me wants to believe it is all marketing.

Oh yeah, my X-Cel 7mm should come tomorrow.

 

[Ray of LIght]

1 hour ago, Mak the Night said:

I think ED glass has something to do with the qualities of anomalous partial dispersion (I’m not exactly sure what that is lol). Apparently it also has a low index of refraction and the focal lengths of individual ED glass lenses can change slightly with temperature because it is less stable than conventional glass or something (kryptonite based? lol). ED glass can remedy a lot of fringing I think. I'm fairly sure FL refers to fluorophosphate glass which is used to make a lot of extra-low-dispersion (ED) lens glass. Before that lanthanum oxide was used I think. Vixen used to advertise EP's as 'lanthanum glass' and I've got a funny feeling TeleVue Radians were made with lanthanum. The cynic in me wants to believe it is all marketing.

Oh yeah, my X-Cel 7mm should come tomorrow.

 

Lol! So sounds like a good eyepiece! Can't waiit to try that one out, may be soon because with the incoming pants weather it gives me a couple of extra recovery days. I would have to barlow a 7mm but it will work great on the Big Cat. The 3x TV was a great investment because if I have to barlow it might as well be the best, and I have to thank you for that!

[Mak the Night]

12 minutes ago, Ray of LIght said:

Lol! So sounds like a good eyepiece! Can't waiit to try that one out, may be soon because with the incoming pants weather it gives me a couple of extra recovery days. I would have to barlow a 7mm but it will work great on the Big Cat. The 3x TV was a great investment because if I have to barlow it might as well be the best, and I have to thank you for that!

I told you the TV x3 is a great investment. They always are lol. Oddly, a 7mm EP (I'm pretty sure it's my first 7mm EP) will give me 336x on the Big Cat (very useful for lunar), 257x on the Bazooka (with 2x Barlow), 186x on the 102mm Mak and 143x on the 90mm Mak. Possibly the perfect high magnification f/l for all four scopes.

[Ray of LIght]

OMG, my 600mm really limits my magnification but with your help I have been able to make the most out of what I have. Now doing solar observing will at least expand my knowledge a little. I would still like to get the 5mm X-Cel because I think 120x might be a useful magnification. I am definitely good for now though!

[Mak the Night]

13 minutes ago, Ray of LIght said:

OMG, my 600mm really limits my magnification but with your help I have been able to make the most out of what I have. Now doing solar observing will at least expand my knowledge a little. I would still like to get the 5mm X-Cel because I think 120x might be a useful magnification. I am definitely good for now though!

I could regularly easily get around 200x on my 102mm Mak. It's the aperture size that really limits magnification resolution. A 102mm will struggle with magnifications over around 208x in my experience. Of course, overall conditions and exit pupil also come into play. Using the 130mm Bazooka again after over a year I've remembered that magnifications of around 260x are pretty easy with it where I live. The 90mm Mak can struggle though, I often observe between around 53x and 67x with the occasional 100x with the 90mm Mak. 143x would be possible on the Moon with very good seeing, but that 90mm aperture is starting to show its limits.

I did find on my 102mm Mak though that around 111x to 130x could be good for lunar/planetary if the conditions weren't particularly brilliant. It's a good magnification for some globular clusters and M42 in my experience too.

[Ray of LIght]

16 hours ago, Mak the Night said:

I could regularly easily get around 200x on my 102mm Mak. It's the aperture size that really limits magnification resolution. A 102mm will struggle with magnifications over around 208x in my experience. Of course, overall conditions and exit pupil also come into play. Using the 130mm Bazooka again after over a year I've remembered that magnifications of around 260x are pretty easy with it where I live. The 90mm Mak can struggle though, I often observe between around 53x and 67x with the occasional 100x with the 90mm Mak. 143x would be possible on the Moon with very good seeing, but that 90mm aperture is starting to show its limits.

I did find on my 102mm Mak though that around 111x to 130x could be good for lunar/planetary if the conditions weren't particularly brilliant. It's a good magnification for some globular clusters and M42 in my experience too.

Do you think my 102 refractor can attain more than a 102 Mak, or about the same? By the way, the 3.2mm Starguider is fairly large but not overly heavy and has purple color coded rings, it has a very nice build quality. Pants weather so maybe the sun will come out by the time I get my solar filter, lol! I also bought a book on solar observing so I'm not flying blind. I guess, IMO, 200x with the upgraded equipment I now have, should be enjoyable for me. If I can get a bit higher under the right conditions that would be ok too.

[Mak the Night]

6 minutes ago, Ray of LIght said:

Do you think my 102 refractor can attain more than a 102 Mak, or about the same? By the way, the 3.2mm Starguider is fairly large but not overly heavy and has purple color coded rings, it has a very nice build quality. Pants weather so maybe the sun will come out by the time I get my solar filter, lol! I also bought a book on solar observing so I'm not flying blind. I guess, IMO, 200x with the upgraded equipment I now have, should be enjoyable for me. If I can get a bit higher under the right conditions that would be ok too.

The 3.2mm looks cool. I figured it would be big, to get a decent eye relief, FOV and field stop on such a short f/l requires some serious optical glass technology lol. I think a 102mm refractor is more efficient with light than a 102mm catadioptric, so it's difficult to say. You don't have the obstruction in the objective that a Maksutov or SCT has for a start. Plus, reflectors just aren't as efficient with the available light as refractors as a whole. Sky-Watcher says that the highest practical power for my Skymax is 204x. Although I've seen 241x touted by some distributors. I personally think it's at its resolution limit at 208x. Lunar viewing is a bit of an anomaly though and I have pushed the Bazooka (resolution limit 260x) to 270x and even 300x on the Moon. TeleVue claim that with good optics (theirs? lol) it can be possible to get 60x for every inch of aperture for scopes of 6" and under. If you translate 102mm directly into its Imperial equivalent and apply the 60x formula you get 241x. It's definitely worth experimenting with though. I did experiment with my 102mm Mak and a pair of 9mm WO SWAN's with my bino and the 1.6x nosepiece to get 231x with some lunar viewing once. It was OK but I don't think the SWAN's were really up to it. Plus, they were pants to look through. What fascinates me is that they cost slightly more (each) than the 9mm Celestron X-Cel, which is a superb eyepiece for just under 60 quid.

[Dave In Vermont]

A refractor trumps (koff!) a Cassegrain any day of the week. As MTN so ably points out - refractors are pure through-put of light, no light coming in being bounced or obstructed. A Maksutov has a 23% obstruction if it's a Skywatcher brand (I asked a good dealer to do the research). Drawback with a refractor with a low F? Blue color around bright objects - and that's not bothering you - or me.

A 102mm frac. with a low F is easy to handle. Once get to higher F and larger objective, they become unwieldy to use. 102 mm. is easy & convenient to use, move, etc. But Maks have their own special charm! But I won't go into that for now.....

'til later -

Dave

[Stu]

Whilst I agree about fracs being very nice to observe with, fast achro fracs can suffer from spherical abberation which limits their abilities to achieve higher magnifications whilst maintaining detail. The other limit is likely to be exit pupil. Once you get to 0.5mm and below floaters start to be an issue aswell as image brightness on the dimmer targets. No problem for the moon though.

Without trawling through the whole thread again, I've no idea if this document has been referenced before, quite probable, but I found it on a search and thought it interesting to read. There is a comment in there about the included amici prism correcting for spherical abberation and thus improving the views through the scope which is naturally under corrected.

The Meade Infinity 102 AZ.pdf

[Dave In Vermont]

Yes - these scopes are not great for close-in detail at high-mag. - but their crystalline views are pretty hard to ignore. No one telescope can do everything, which I think we've covered somewhere. This thread must have covered everything from Einstein's Theory of General Relativity to How to Remove a Lens Cap! 

If high-power is desired, I'd take the Maksutov-Route. With a focal-ratio of F/12-ish common, they will excel. My signature bears out I have both a fast refractor, and a Maksutov. So Ray, brace yourself: You may get bitten by the Other Telescope 'bug!'

Not suggesting, but this 'bug' causes a desire to expand the 'FAMILY.' Hence - my signature below..... No vaccine is currently available.

,

Dave

[Stu]

It would certainly be great to see Ray getting some decent scope time in to get used to things and understand what works for him and what doesn't

[Ray of LIght]

42 minutes ago, Stu said:

It would certainly be great to see Ray getting some decent scope time in to get used to things and understand what works for him and what doesn't

Yep, looking forward to recuperating enough to spend the better part of a decent night out there observing. Going to rain for the next couple of days so hopefully when things clear. Some great info and insight Mak, Dave and Stu. I appreciate it. Will see about adding to the "family" once I have raised my first child Dave, lol!! I read Bill Steen's great review/information a couple of times: excellent. I have tested my Baader Fringe Killer and it did improve views of Jupiter, I have yet to try it stacked with my neodymium though in my WO helical focusing correct image diagonal. Should be interesting. Quick solar question Stu: what f/l eyepiece would be good for solar observing? I bought a book on the subject of solar observing but I figured real life experience would be great. Should I remove my filters from the nosepiece of my diagonal? Thanks for all the help and support guys!

[Stu]

6 minutes ago, Ray of LIght said:

Yep, looking forward to recuperating enough to spend the better part of a decent night out there observing. Going to rain for the next couple of days so hopefully when things clear. Some great info and insight Mak, Dave and Stu. I appreciate it. Will see about adding to the "family" once I have raised my first child Dave, lol!! I read Bill Steen's great review/information a couple of times: excellent. I have tested my Baader Fringe Killer and it did improve views of Jupiter, I have yet to try it stacked with my neodymium though in my WO helical focusing correct image diagonal. Should be interesting. Quick solar question Stu: what f/l eyepiece would be good for solar observing? I bought a book on the subject of solar observing but I figured real life experience would be great. Should I remove my filters from the nosepiece of my diagonal? Thanks for all the help and support guys!

Somewhere around x40 to x60 often works best. The sun tends to go against standard practice in that it is not necessarily at it's best when at it's highest. Often the convection currents caused by the ground and atmosphere heating can make the seeing very poor around midday. Best options are early morning and later in the afternoon, either before or after the heat of the day. It's a matter of finding a balance between the sun being high enough to be out of the worst of the atmosphere, but before everything starts to heat up. If the seeing is really steady, then I do use higher magnifications, up to x150, particularly to pick out the granulation cells but I use a Herschel Wedge in a Tak scope so will be able to push things harder than you. Use the x40/60 as a start point and see how you go.

Because you have the full aperture solar film, you can leave filters on the diagonal as no heat enters the OTA. I use a Baader Continuum filter which works very well, but if you have a UHC can be very effective too, outside that a good green filter, not sure of numbers etc.

Make sure you are methodical about putting the filter on and taking it off ie make sure you point the scope away from the sun before you remove it. Cover or remove your finder..blah, blah, blah, you know the drill but do take care.

[Mak the Night]

1 hour ago, Stu said:

Whilst I agree about fracs being very nice to observe with, fast achro fracs can suffer from spherical abberation which limits their abilities to achieve higher magnifications whilst maintaining detail. The other limit is likely to be exit pupil. Once you get to 0.5mm and below floaters start to be an issue aswell as image brightness on the dimmer targets. No problem for the moon though.

Without trawling through the whole thread again, I've no idea if this document has been referenced before, quite probable, but I found it on a search and thought it interesting to read. There is a comment in there about the included amici prism correcting for spherical abberation and thus improving the views through the scope which is naturally under corrected.

The Meade Infinity 102 AZ.pdf

Fringing is problem on achromatics, but it can be ameliorated or alleviated somewhat with various minus blue/cyan filters though, which can in turn improve magnification resolution capability. Exit pupil is always the limiting factor IMO. I can comfortably get to 0.47mm (208x) on my 102mm Mak, I think above that is pushing it, but conditions can often dictate ultimate magnification.

[Stu]

Just now, Mak the Night said:

Fringing is problem on achromatics, but it can be ameliorated or alleviated somewhat with various minus blue/cyan filters though, which can in turn improve magnification resolution capability. Exit pupil is always the limiting factor IMO. I can comfortably get to 0.47mm (208x) on my 102mm Mak, I think above that is pushing it, but conditions can often dictate ultimate magnification.

CA and SA are obviously different things, CA need not reduce the resolving ability of the scope at higher powers, but SA surely will

[Mak the Night]

17 minutes ago, Stu said:

CA and SA are obviously different things, CA need not reduce the resolving ability of the scope at higher powers, but SA surely will

Chromatic aberration can interfere with the magnification if it is particularly noticeable though. Spherical aberration probably will, but even with an achromat that shouldn't be a problem if you don't exceed the 0.5 exit pupil limit by too much.

Celestron claim that the magnification limit of this 102mm refractor, which I believe is an achromatic, is 241x for instance.

 

 

[Ray of LIght]

4 hours ago, Stu said:

Somewhere around x40 to x60 often works best. The sun tends to go against standard practice in that it is not necessarily at it's best when at it's highest. Often the convection currents caused by the ground and atmosphere heating can make the seeing very poor around midday. Best options are early morning and later in the afternoon, either before or after the heat of the day. It's a matter of finding a balance between the sun being high enough to be out of the worst of the atmosphere, but before everything starts to heat up. If the seeing is really steady, then I do use higher magnifications, up to x150, particularly to pick out the granulation cells but I use a Herschel Wedge in a Tak scope so will be able to push things harder than you. Use the x40/60 as a start point and see how you go.

Because you have the full aperture solar film, you can leave filters on the diagonal as no heat enters the OTA. I use a Baader Continuum filter which works very well, but if you have a UHC can be very effective too, outside that a good green filter, not sure of numbers etc.

Make sure you are methodical about putting the filter on and taking it off ie make sure you point the scope away from the sun before you remove it. Cover or remove your finder..blah, blah, blah, you know the drill but do take care.

Thanks Stu! Just what I was looking for!

[Ray of LIght]

4 hours ago, Ray of LIght said:

Thanks Stu! Just what I was looking for!

Oh, I have a Baader UHC filter and a 6x6 sheet of solar filter film that I can use to cover my Rigel Quickfinder. I have a #56 green filter also, I can try both out and see how they work. Thanks again!

4 hours ago, Ray of LIght said:

 

[Ray of LIght]

13 hours ago, Ray of LIght said:

Oh, I have a Baader UHC filter and a 6x6 sheet of solar filter film that I can use to cover my Rigel Quickfinder. I have a #56 green filter also, I can try both out and see how they work. Thanks again!

 

Stu, Mak: do you think my 10mm Luminos (82 degree AFoV), which would give me 60x, is a good eyepiece to try for solar viewing? Most of my kit actually fits the bill, I was just curious about the Luminos in particular. Thanks again!