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Lunt Herschel wedge plus?


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I want to move out of my imaging comfort zone into solar observing (Among other things)

Looking at Herschel wedges I'm unsure if I also need an objective filter. It looks like I don't, the wedge doing all the work of dimming the sun, but want to make sure.

So I'm thinking (Because I'm on a budget), Lunt Herschel wedge and 1.25" Baader continuum filter to go on my Megrez 90. I have 25mm and 9mm Mead Plossls, and will add a 15mm to the list.

What have I missed? I'm sure there's something but want to nail it before SGL 2017.

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I'm hardly an expert solar observer (or imager, come to that!), but have been enjoying white light observing over the last couple of years, mostly with either an Equinox ED80 (500mm) or a Starwave ED70 (420mm) plus - exactly as per your thinking - a Lunt Herschel Wedge & a Baader SCF.  My go-to eyepiece is normally a Baader mk3 zoom.  Views with this combo are sharp, clear, and with nice contrast, and an enoyable amount of detail.  So IMHO, no, I don't you're missing much.

As a general rule, I find that the level of achievable contrast and detail is hugely dependent on sky conditions.  Any hint of that irritating thin, whispy high stuff is a right PITA.  Irrespective of conditions though, FWIW I find that the Lunt wedge + Baader SCF combo delivers far better views than the front-mounted filter that I have on my 6" SCT.

Cheers

Simon

Edited by Chinapig
Typos!
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Yes, I've done exactly the same with my ST120 and a Lunt wedge.  I don't have an SCF, but one is on my shopping list.  The only other thing that's handy is a solar finder.  Otherwise you can just get on with it.

James

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1 hour ago, DaveS said:

I want to move out of my imaging comfort zone into solar observing (Among other things)

Looking at Herschel wedges I'm unsure if I also need an objective filter. It looks like I don't, the wedge doing all the work of dimming the sun, but want to make sure.

So I'm thinking (Because I'm on a budget), Lunt Herschel wedge and 1.25" Baader continuum filter to go on my Megrez 90. I have 25mm and 9mm Mead Plossls, and will add a 15mm to the list.

What have I missed? I'm sure there's something but want to nail it before SGL 2017.

Hi! 

That's correct.

The Lunt Herschel wedge only works with refractors. If yours have an additional lenses (e.g. flattener), you need to make sure that they are suitable for solar observation using a Herschel Wedge. Same thing for oil-spaced optics. @Merlin66 is expert on Solar obs and hopefully he will join this conversation with more details than mine. 

The current version of Lunt Herschel Wedge incorporates a ND3.0 filter, which is necessary for visual observation of the Sun. Some previous models didn't include this, and this filter was bought apart. (Just a warning if you buy it s/h).

The 1.25" solar continuum filter is a great tool for improving the observation of granulation. It will give the Sun a green tint, but I feel one gets used to it. 

If you find that the Sun at the eyepiece is still to bright for your eye (e.g. at low power), you might want to consider a single polarising filter to attach to the solar continuum filter in cascade. Doing so, you can control the brightness by turning the eyepiece.

Edited by Piero
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That's great.

I have a shopping basket ready on the FLO site so will push the button. The 1.25" wedge should do me as I don't see myself getting anything bigger than the Megrez 90 for solar. The 130 apo is dedicated to imaging.

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Piero's advice above is good and worth taking on board.

I use the 1.25" Lunt Herschel Wedge with a 3.0 ND filter incorporated in the wedge (bottom of the eyepiece drawtube) and a single polarising filter on the eyepiece. This works well with my 100mm and 120mm refractors. I'd probably not try a larger aperture refractor with the 1.25" wedge but I may be being too cautious there (caution is best with the Sun !). Doublet air spaced refractors with no sub-aperture  correctors or anything else in the light path between the objectve and the wedge seems the safe way to do it.

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The lunt herschel wedge with SC filter is an outstanding package. On my Equinox 80mm solar granulation is very apparent and is by far the best WL set up I have experienced. It was superior to front mounted baader film on an 8" newt.   Also, best WL I have imaged as well. Ex.

AR2671

114316GGB

 

July 8, 2017 

144722Gborder

 

AR2665

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AR2663

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The only gripe I had with the lunt 1.25" is that the nose piece gets secured in my Equinox with a single set screw. There was a bevel of some kind on the male piece, and the set screw did not secure it tightly in the standard adapter, which resulted in dumping a 13mm nagler with SC filter onto the grass one time.

After that, I opted for a baader 2" to 1.25" click lock adapter and my woes were solved. 

Edited by Tyson M
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The Herschel wedge is 100% safe to use on refractors ( I exclude the oil-spaced objective due to lack of accurate data) . Al Nagler and all the other manufactures of Petzval type refractors have put in in writing that their scopes are 100% OK to use.

The "sweet spot" seems to be around 120mm aperture, for good seeing conditions.

I'm testing out a comparison between the Baader Continuum (excellent!) and a narrow band OIII filter - I've seen some great images where the OIII actually appears to give even better contrast....

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9 minutes ago, Merlin66 said:

John,

I'd love the hear your feedback......

I'll be happy to let you know Ken :smiley:

One question that has been in my mind recently is whether the Lunt 1.25" HW would be safe to use with my 130mm F/9 triplet refractor ?. The objective is air spaced. What do you think ?

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10 hours ago, Highburymark said:

Dave, seems like you're well set. But you might want to look at the newish Lacerta wedge as an alternative to the Lunt. Has been very well reviewed, and great value to boot

Thanks Mark.

I didn't know about the Lacerta wedge, so pushed the button on the Lunt kit, should be arriving this week.

As I have a spare [OIII] filter (Baader) kicking around I may compare it with the Baarder SCF.

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1 hour ago, DaveS said:

Thanks Mark.

I didn't know about the Lacerta wedge, so pushed the button on the Lunt kit, should be arriving this week.

As I have a spare [OIII] filter (Baader) kicking around I may compare it with the Baarder SCF.

Would be interested to hear more on that comparison twixt an OIII and SCF - a good tip raised in this thread that I hadn't heard before.  Good luck with the new kit, hope you enjoy it!

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