Observing with Smaller Apertures: 130mm and Below

[Ray of LIght]

21 minutes ago, Mak the Night said:

I'm pretty sure my Orion 9x50 is GSO. 

It's about half the aperture of my Skymax! The 9x50 has a 5° FOV which is about 10 Full Moons. Oddly, the Orion 6x30 I use on my 90mm Mak has a 7° FOV, which is about 14 Full Moons. To be honest, I think the 6x30 would be all that was needed on any scope under 200mm. Once you've used an RACI you wonder how you did without one.

The Orion is 64.80 US. I will be getting it. I wanted to get the X-Cel 2x Barlow first but I think the RACI will help me more right now. Thanks Mak; I knew I needed one but I thought they were too expensive. They are not. The Orion 6x30 it is.

[Ray of LIght]

37 minutes ago, Mak the Night said:

I'm pretty sure my Orion 9x50 is GSO. 

It's about half the aperture of my Skymax! The 9x50 has a 5° FOV which is about 10 Full Moons. Oddly, the Orion 6x30 I use on my 90mm Mak has a 7° FOV, which is about 14 Full Moons. To be honest, I think the 6x30 would be all that was needed on any scope under 200mm. Once you've used an RACI you wonder how you did without one.

Thsnks Mak! I was going to get the X-Cel 2x Barlow first but the RACI will do me a lot more good right now. So the Orion 6x30 it is! Always thought they were too expensive but it is 64.80 US on Amazon.

[Mak the Night]

25 minutes ago, Ray of LIght said:

The Orion is 64.80 US. I will be getting it. I wanted to get the X-Cel 2x Barlow first but I think the RACI will help me more right now. Thanks Mak; I knew I needed one but I thought they were too expensive. They are not. The Orion 6x30 it is.

Yeah, if I'd realised I'd have got the 6x30 for my Skymax instead of the 9x50. The 9x50 was too heavy for the 90mm Mak so I got an Orion 6x30 for that. I just couldn't use the 90mm otherwise.

I'm seriously considering using the 6x30 on the Bazooka as I often nudge the 9x50 with my elbow when I'm setting the clutches.

 

[Ray of LIght]

Can't wait to get it now! My back will thank you, and me!

[Ray of LIght]

Oh, the RACI pictured is the 6x30, right? Looks like the same mount I have.

[Mak the Night]

1 hour ago, Ray of LIght said:

Oh, the RACI pictured is the 6x30, right? Looks like the same mount I have.

The top picture is the 6x30, the bottom is a crop from the same picture that is my current avatar and shows the 9x50 mounted on the Bazooka. I'm pretty sure your scope has a standard Synta foot. I have to stand up and lean over the OTA to reach the RA and Dec clutches. Occasionally my left elbow catches the RACI. Pointing south the Bazooka is relatively easy to operate from a seated position. West can be more difficult. Either way, I usually stand to align the aperture roughly where the target is whilst looking down the Bazooka rifle-style to aim it, then I lean over and roughly get the target in the RACI cross hairs using my left arm and by physically holding my body against the OTA to steady it. I then have to tighten both clutches, and lean over again to make sure I'm still roughly on target in the RACI. Then I have to loosen the OTA cradle screws and rotate the OTA to a convenient position for observing, which is a guess usually, and all with my left arm only. Only then I can sit in my observing (garden) chair and re-rotate the OTA if necessary. Next I have to lean forward and reacquire the target in the RACI utilising the slo mo controls only. The Dec control is usually easy but the RA is awkward the more west I'm pointed. Finally, I can then try and find the target in the eyepiece itself! My back suffers as I get a lot of compensatory pain as the non-paralysed muscles try to do all the work. Once I've acquired the target in the RACI I can normally remain seated. So yes, it should save your back some. I couldn't really view with the Bazooka in a seated position if it wasn't for the RACI.

[Mak the Night]

Well, I had about an hour viewing before the clouds came back. I’d set up by 21:15 anticipating a bit of a clear sky. Unfortunately the sky had other ideas and it rained on me so I packed up. After a few minutes I noticed a bit of bright sky ... and Jupiter!

So I set up again and had a few minutes of a setting Jupiter with the #8 Light Yellow at 200x. I could see all four moons, just about, as the transparency was a bit pants. The GRS was visible and the yellow filter made it look very dark, almost black and also darkened the blue twilight background, which I expected. There was some cloud detail but after only a short time I slewed towards Mars. So I didn’t have a lot of time to evaluate Jupiter and the #8.

Mars looked good at 257x and I could just about make out the Mare Acidalium and Mare Erythraeum again. The phase was quite evident.

The northern polar cap seemed even more prominent, although this is often the case a few weeks after Opposition. The #8 made Mars a tad ‘orangey’ and apart from that, to be honest I couldn’t see much difference between it and the Baader Neodymium.

Saturn was a tad grainy at 257x and 200x and I could see Titan. I’m pretty sure I could see Dione and Rhea as well, but before I had a chance to step down the magnification the clouds came back.

I did get to hear ‘Screechy’ the screech owl again though even though I couldn’t see him tonight. I didn’t see or hear the badger either, although mainly he stays in my neighbour’s garden. He normally pegs it when I shine the red light torch on him. The Pellor is so powerful it terrifies the neighbourhood cats as well lol.

[Mak the Night]

Saturn from Dione (Celestia 1.6.1).

Saturn from Rhea.

[Ray of LIght]

Good stuff Mak! It appears the #8 yellow is fairly beneficial. I will try it along with the #11 and #82A. It will be a little cooler and sunny starting Sunday so, while night observing is a bit difficult for the next few days, I will do solar in the meantime. I will align the Sol-Searcher and test the #47. The Baader UHC-S seemed to help. I am hoping to order the Orion RACI on the 20th when receive my disability check. There have been air quality alerts for the past few days, which of course has kept me indoors in A/C because of my recent lung surgery. That should break by Sunday. That Pellor is nice. Does it shine red and white? I haven't used the Agena light yet but it looks ok. Back in a bit.

[Ray of LIght]

On July 4, 2016 at 09:29, ronin said:

For magnifications I see 2x diameter often quoted but personally I suspect that the previous idea of 1.5x diameter is a much more realistic value. Meaning that to me something like 150x is your maximum.

I will also throw in that if the scope is fast, as you say, then maybe less again. Fast scopes are more difficult to produce and so tend to suffer more aberrations. A fast lens is in a way just too "Spherical" to produce a good image. So rule or no rule or whichever rule you want to choose the lens just will not do it.

 

Myth #5: The highest useful magnification is 50x per inch of aperture.

What is "useful"? Although small telescopes little affected by the atmosphere may give pleasing images even up to 100x per inch of aperture, no more detail is seen than at 50x per inch. On the other hand, large instruments, more affected by atmospheric seeing, may top out at 20x or 30x per inch. In practice, a 3- or 4-inch refractor may work well at 200x, but it is rare indeed that any size instrument benefits from more than two or three times that magnification.

http://www.skyandtelescope.com/astronomy-equipment/choosing-your-telescopes-magnification/

[Mak the Night]

1 hour ago, Ray of LIght said:

Good stuff Mak! It appears the #8 yellow is fairly beneficial. I will try it along with the #11 and #82A. It will be a little cooler and sunny starting Sunday so, while night observing is a bit difficult for the next few days, I will do solar in the meantime. I will align the Sol-Searcher and test the #47. The Baader UHC-S seemed to help. I am hoping to order the Orion RACI on the 20th when receive my disability check. There have been air quality alerts for the past few days, which of course has kept me indoors in A/C because of my recent lung surgery. That should break by Sunday. That Pellor is nice. Does it shine red and white? I haven't used the Agena light yet but it looks ok. Back in a bit.

I think the #8 is a good contrast filter at high magnification on smaller scopes. It's possible that the #15A Dark Yellow Filter (67% T) and #12 Deep Yellow (74% T) could work on the right target with a large enough exit pupil, but the 83% transmission of the #8 definitely shows. It's interesting that yellow/green filters work well for Saturn. Sounds like a good plan to do solar while the weather's like it is. This is why I like twilight observing, as it gets darker and cooler it can seriously raise my blood pressure, earlier in the evening, like in twilight, it's not so bad. I still tend to stay out as late as I can though. Luckily I have an anorak and thermal underwear lol.

If it seems OK at about 21:50 I'll have another stab at a twilight Jupiter.

The Pellor only shines red light. There are three strengths: 1/ Radiation Hazard, 2/ Ridiculously High Enough To Start Small Brush Fires, and 3/ Light Sabre. It also flashes SOS in Morse, which isn't as useful as you think. lol

[Ray of LIght]

49 minutes ago, Mak the Night said:

I think the #8 is a good contrast filter at high magnification on smaller scopes. It's possible that the #15A Dark Yellow Filter (67% T) and #12 Deep Yellow (74% T) could work on the right target with a large enough exit pupil, but the 83% transmission of the #8 definitely shows. It's interesting that yellow/green filters work well for Saturn. Sounds like a good plan to do solar while the weather's like it is. This is why I like twilight observing, as it gets darker and cooler it can seriously raise my blood pressure, earlier in the evening, like in twilight, it's not so bad. I still tend to stay out as late as I can though. Luckily I have an anorak and thermal underwear lol.

If it seems OK at about 21:50 I'll have another stab at a twilight Jupiter.

The Pellor only shines red light. There are three strengths: 1/ Radiation Hazard, 2/ Ridiculously High Enough To Start Small Brush Fires, and 3/ Light Sabre. It also flashes SOS in Morse, which isn't as useful as you think. lol

Lol! I think I have the #12, not sure about the other, I will check. I will let you know how the #47 works on the Sun. And now I'm psyched about the RACI finder! Plus it will be nice to be able to switch back and forth between the RACI and the Quickfinder. Something tells me the Quickfinder may be relegated to the back seat but it will still be good to have and pops on and off easily, the base stays where it is. Bsck in a bit.

[Mak the Night]

The RACI can be fiddly to set up, but once it is it should be fine. I think I bought the 15A Dark Yellow and 12 Deep Yellow to replace the Celestron ones I had that had dodgy threads. The TS Optics/GSO filters fit everything.

[Ray of LIght]

36 minutes ago, Mak the Night said:

The RACI can be fiddly to set up, but once it is it should be fine. I think I bought the 15A Dark Yellow and 12 Deep Yellow to replace the Celestron ones I had that had dodgy threads. The TS Optics/GSO filters fit everything.

I was going to pick your brain when I get it if you wouldn't mind. I know it's a daytime  project, even though I aligned my Quickfindet using the moon! Yes, the GSO filters are good on everything I have threaded them on. Have to check my filters when I get home. At least they don't break the bank!

[Ray of LIght]

41 minutes ago, Ray of LIght said:

I was going to pick your brain when I get it if you wouldn't mind. I know it's a daytime  project, even though I aligned my Quickfindet using the moon! Yes, the GSO filters are good on everything I have threaded them on. Have to check my filters when I get home. At least they don't break the bank!

Have to check about the deep yellow. Looks like maybe a good solar filter.

[Mak the Night]

47 minutes ago, Ray of LIght said:

I was going to pick your brain when I get it if you wouldn't mind. I know it's a daytime  project, even though I aligned my Quickfindet using the moon! Yes, the GSO filters are good on everything I have threaded them on. Have to check my filters when I get home. At least they don't break the bank!

RACI's are tricky for me as I don't totally have the use of my right arm/hand back yet. There's a metal spring loaded thumb screw and two others. You pull the spring loaded one out and rotate the finder scope in its mount to where you want it. Be careful not to lose the rubber band around the scope as it cushions it in the mount. Once it is at the angle you need it's fairly straightforward to adjust the other two screws to align it with the main scope. Use a 32mm EP or longer, although with your scope a 25mm might do, and centre a target (preferably stationary lol) in the main scope. Then use the two other screws on the finder (not the spring loaded one) to adjust the X and Y settings until you have centred the target in the finder. The finder reticule can unthread a little so you can orient the cross hairs. Also, it probably won't be in focus, so you unthread the objective eyepiece a bit and move the collar to get it focused. Mine aren't perfect but as long as it gets you to the target it should be OK. Be prepared to pull your own hair out, swear and shout at the cat a bit though lol.

[Ray of LIght]

32 minutes ago, Mak the Night said:

RACI's are tricky for me as I don't totally have the use of my right arm/hand back yet. There's a metal spring loaded thumb screw and two others. You pull the spring loaded one out and rotate the finder scope in its mount to where you want it. Be careful not to lose the rubber band around the scope as it cushions it in the mount. Once it is at the angle you need it's fairly straightforward to adjust the other two screws to align it with the main scope. Use a 32mm EP or longer, although with your scope a 25mm might do, and centre a target (preferably stationary lol) in the main scope. Then use the two other screws on the finder (not the spring loaded one) to adjust the X and Y settings until you have centred the target in the finder. The finder reticule can unthread a little so you can orient the cross hairs. Also, it probably won't be in focus, so you unthread the objective eyepiece a bit and move the collar to get it focused. Mine aren't perfect but as long as it gets you to the target it should be OK. Be prepared to pull your own hair out, swear and shout at the cat a bit though lol.

I'l yell at my dog, but he's deaf (really), so he won't care, lol! Great instructions, thank you! When my dog turns his back on me and I start pulling my hair out, I will bother you again! Which will hopefully be soon. What a fine looking Achromat it will be, lol!

[Mak the Night]

55 minutes ago, Ray of LIght said:

I'l yell at my dog, but he's deaf (really), so he won't care, lol! Great instructions, thank you! When my dog turns his back on me and I start pulling my hair out, I will bother you again! Which will hopefully be soon. What a fine looking Achromat it will be, lol!

I think you'll be OK. I can't speak for the dog lol. Honestly, after using an RACI for a bit you'll honestly wonder how you found anything before.

[Mak the Night]

1 hour ago, Ray of LIght said:

Have to check about the deep yellow. Looks like maybe a good solar filter.

Yeah, it could work.

[Ray of LIght]

1 hour ago, Mak the Night said:

Yeah, it could work.

I ordered the #15, didn't have it. I will report on it's effectiveness, or lack thereof, lol!

[Mak the Night]

2 hours ago, Ray of LIght said:

I ordered the #15, didn't have it. I will report on it's effectiveness, or lack thereof, lol!

I think it should be good for solar. I observed a setting twilight Moon at 128.5x earlier, the #8 didn't help much as the conditions weren't good. I saw Mars for a few minutes at the same magnification and even went up to 150x with a 6mm Hutech Abbe ortho'. It didn't look bad and I could see the phase anyway. After that the clouds came.

Not exactly the largest eye lens lol. The 43° FOV doesn't help. Very sharp 'contrasty' view though considering the bad transparency.

[Ray of LIght]

1 hour ago, Mak the Night said:

I think it should be good for solar. I observed a setting twilight Moon at 128.5x earlier, the #8 didn't help much as the conditions weren't good. I saw Mars for a few minutes at the same magnification and even went up to 150x with a 6mm Hutech Abbe ortho'. It didn't look bad and I could see the phase anyway. After that the clouds came.

Not exactly the largest eye lens lol. The 43° FOV doesn't help. Very sharp 'contrasty' view though considering the bad transparency.

OMG, my first set of short FL Plossls looked like that. I couldn't look through them! That is a very good eyepiece but that's why I had to replace them with large eye lens, LER eyepieces what with my glasses and lousey vision. Anyway, glad you got some observing in even with not optimal conditions. I hope the #15 gives me a nice solar view, according to the reviewer on Agena, it should. But you know how that goes!

[Mak the Night]

19 minutes ago, Ray of LIght said:

OMG, my first set of short FL Plossls looked like that. I couldn't look through them! That is a very good eyepiece but that's why I had to replace them with large eye lens, LER eyepieces what with my glasses and lousey vision. Anyway, glad you got some observing in even with not optimal conditions. I hope the #15 gives me a nice solar view, according to the reviewer on Agena, it should. But you know how that goes!

It's not too bad if you can get used to it.

The 18mm is a bit easier to look through. I think they go as short as 4mm! I think even I'd have difficulty with that. It wasn't too bad keeping Mars in frame at 150x even with a 43° FOV. I think Mars needs at least 200x though. I only really got a few minutes observing in a couple of hours, but the exercise has done me good. lol

[Ray of LIght]

Just a discussion question; I know you're not into solar but I was wondering if should remove my neodymium filter from my diagonal nosepiece and just leave my Fringe Killer when I solar observe. I can thread my other filters (#15, #47, UHC-S etc) directly on the eyepiece as I wish to get the best view. I was also contemplating the Baader Solar Continuum Filter to round out my solar kit. My RACI will have to come first of course! The picture is my 102 set up for solar.

[Mak the Night]

I'm not sure to be honest Ray. I can't see the neodymium being of much use viewing solar. At least with the Sun you don't have to worry about it being too dim to find the image.