Increasing power from an 8mm...worth it?

[John]

I have the Pentax XW's in 10, 7, 5 and 3.5mm focal lengths. I find them superb for deep sky or planetary work although the 3.5mm does not get much use with my 12" F/5.3 dobsonian because it produces 454x which is too much power for most purposes. I owned a 10mm Delos for a while and found it very, very similar to the Pentax XW of that focal length.

The Vixen SLV's are just about as good optically as the Delos / XW's but with an apparent field of 50 degrees. I found the 6mm SLV matched a Baader Genuine ortho 6mm in all performance respects and was more comfortable to observe with.

The Vixen LV's are decent eyepieces but not, to my eye, quite as good as the SLV's / Delos / Pentax XW's. The LV's light transmission is lower which affects deep sky objects I found and their light scatter is a little more obvious around brighter objects.

Obviously there are some significant price differences between these to take account of.

A couple of my favourite planetary eyepieces with my 12" dob are the 8mm (199x) and 6mm Ethos (265x) but we are in another price category again with those.

A well reputed but somewhat more reasonably priced 6mm eyepiece is the William Optics SPL 6mm.

 

[Sirius Starwatcher]

The EP I seem to use the most, when seeing is good is my Williams Optics SPL 6mm it compliments the Dob very nicely IMHO.

[SacRiker]

12 hours ago, Jimtheslim said:

which 6mm are you going for?

I see all the expensive stuff being thrown around on here, but I can't afford that at the moment. I ordered a 6mm Baader Classic Orthoscopic.

[Jimtheslim]

32 minutes ago, SacRiker said:

I see all the expensive stuff being thrown around on here, but I can't afford that at the moment. I ordered a 6mm Baader Classic Orthoscopic.

I'm after one in a 10mm

[Louis D]

The 6mm Baader Classic Orthoscopic will be a good choice as long as you can keep the object centered so the short eye relief isn't such an issue.  By keeping it centered, you can back off from the eyepiece a little bit.

Be sure to post a first light report when you get the chance.

[SacRiker]

The 6mm Baader arrived last night -- but it was cloudy all night! First light report coming soon (hopefully).

[Jimtheslim]

5 hours ago, SacRiker said:

The 6mm Baader arrived last night -- but it was cloudy all night! First light report coming soon (hopefully).

Just ordered the 10mm. I will be interested to hear how you get on with the 6mm with your scope. I got sick of waiting for one to come up second hand and figured I wouldn't loose much if I don't get on with it.

[Louis D]

I have a 6mm Kellner that came with an ST80 years ago.  It is surprisingly sharp in the middle 20 degrees.  I can just use it without glasses.  My astigmatism isn't too bad at the small exit pupil.  I can even track an object with my dob using it.  Do I prefer my 5.2mm Pentax XL and 7mm Pentax XW in that power range?  Yeah, it's a no brainer to choose them; but, the Kellner is more than serviceable.

I would think that the 6mm Baader Ortho should run rings around my Kellner.

[SacRiker]

11 minutes ago, Louis D said:

I would think that the 6mm Baader Ortho should run rings around my Kellner.

Unfortunately I've been traveling lately for work and the nights when I have been home have been cloudy. Hoping to maybe use the EP tonight or tomorrow.

[John]

I think the Baader Clasic orthos are superb performers for their cost. They compared very well to the much admired Baader Genuine Ortho's when I compared them a while back.

Baader have gone for a plain exterior and concentrated on excellent optics with these. The barlow lens in the same range is a really good optic as well. It gives 2.25x amplification when the eyepiece is inserted in the barlow but with the Classic orthos you can also screw the lens element of the barlow into the eyepiece barrel where it provides an interesting 1.3x amplification. The barlow plus the 3 orthos gives a very wide range of possibilities

 

[Jimtheslim]

15 hours ago, John said:

I think the Baader Clasic orthos are superb performers for their cost. They compared very well to the much admired Baader Genuine Ortho's when I compared them a while back.

Baader have gone for a plain exterior and concentrated on excellent optics with these. The barlow lens in the same range is a really good optic as well. It gives 2.25x amplification when the eyepiece is inserted in the barlow but with the Classic orthos you can also screw the lens element of the barlow into the eyepiece barrel where it provides an interesting 1.3x amplification. The barlow plus the 3 orthos gives a very wide range of possibilities

 

On to my wishlist it goes! Looks like a good Barlow. Although I don't really use mine (standard stock Skywatcher), when I sell my old scope along with the barlow I will probably start to want one! With the 10mm BCO I have just ordered this would give me around 4.5mm and 7.5mm. hmmm.....

[SacRiker]

Just a quick update -- I finally used the 6mm Baader last night. Saturn looked special. I could, at times, make out the division in the ring. I also used it on Mars, but couldn't make out any details whatsoever. Not sure if it was just bad seeing though, there was lots of heat coming off the houses and such.

[Jimtheslim]

Being so low and prone to atmospheric turbulence it will be difficult to get Saturn looking good for any length of time. I had fantastic views of Jupiter a few nights ago and turning to Saturn it was terrible. Wait until it is as high as it will get and then spend a long time observing, you will get occasional phases of stillness, you just need to learn to make out as much as you can when they do happen. I am still waiting to use my 10mm BCO, can't wait. If the high cloud shifts I'll be on it!

[SacRiker]

1 hour ago, Jimtheslim said:

Being so low and prone to atmospheric turbulence it will be difficult to get Saturn looking good for any length of time. I had fantastic views of Jupiter a few nights ago and turning to Saturn it was terrible. Wait until it is as high as it will get and then spend a long time observing, you will get occasional phases of stillness, you just need to learn to make out as much as you can when they do happen. I am still waiting to use my 10mm BCO, can't wait. If the high cloud shifts I'll be on it!

One problem I'm running into is focus. I'm constantly adjusting the focus thinking that I can get it "just a little clearer." I know this is actually hurting my seeing though as the scope is shaking. 

[Jimtheslim]

I'm the same, constantly unable to stop trying to get that perfect focus, it's especially difficult on something like Saturn when it won't sit still! Like I say, you just have to wait for and enjoy those fleeting moments of stillness and clarity when they happen

[SacRiker]

6 hours ago, Jimtheslim said:

I'm the same, constantly unable to stop trying to get that perfect focus, it's especially difficult on something like Saturn when it won't sit still! Like I say, you just have to wait for and enjoy those fleeting moments of stillness and clarity when they happen

Sometimes when the planet is fuzzy (due to heat rising) I  try to use the closest star (visible in the EP) to get my focus dialed in. Is this a good technique or is the planet likely to require a different level of focus?

[Jimtheslim]

41 minutes ago, SacRiker said:

Sometimes when the planet is fuzzy (due to heat rising) I  try to use the closest star (visible in the EP) to get my focus dialed in. Is this a good technique or is the planet likely to require a different level of focus?

If you can locate Titan nearby, this will look like a star, try and make this as small as possible, otherwise just use the disc of the planet as a reference to make as small as possible. When I observe Jupiter I make it's moons as small as possible, but even then I question myself as to whether the planet is in perfect focus and continue fiddling! I think you just need to make the planet as small and as focused as possible, then wait to see the odd glimpse of good seeing. If you start using nearby stars you'll likely not take the time to look at the planet itself.

[SacRiker]

3 minutes ago, Jimtheslim said:

If you can locate Titan nearby, this will look like a star, try and make this as small as possible, otherwise just use the disc of the planet as a reference to make as small as possible. When I observe Jupiter I make it's moons as small as possible, but even then I question myself as to whether the planet is in perfect focus and continue fiddling! I think you just need to make the planet as small and as focused as possible, then wait to see the odd glimpse of good seeing. If you start using nearby stars you'll likely not take the time to look at the planet itself.

I think I saw Titan but didn't realize what I was looking at.

[Jimtheslim]

It can be very feint, especially during these lighter nights, check it out on stellarium before going out so you know where it should be.

[Ricochet]

16 hours ago, SacRiker said:

Sometimes when the planet is fuzzy (due to heat rising) I  try to use the closest star (visible in the EP) to get my focus dialed in. Is this a good technique or is the planet likely to require a different level of focus?

In my scope stars and planets focus at slightly different points but if what you are looking at is in fact a moon of the planet using that as a reference works well.