Herschel wedge

[TSRobot]

Oh yes yes it has. All spotless and well packed. 

The Lunt instructions say it MUST be used with the polarising filter or continuum filter at all times. Is this true?

The ND filter appears to be solidly fitted to make it difficult to remove which is a sensible build idea.

[AdeKing]

1 minute ago, LukeSkywatcher said:

That's a good price. I assume it has the ND filter built in?

The ND filter is fitted internally and is non-removable in the Lunt wedge, at least it is on mine.  

.........well as non-removable as it can be without a significant amount of effort involving an oil filter strap wrench anyway ?.

Insomuch as it can be removed if you're really really determined.

[LukeSkywatcher]

9 minutes ago, TSRobot said:

Oh yes yes it has. All spotless and well packed. 

The Lunt instructions say it MUST be used with the polarising filter or continuum filter at all times. Is this true?

The ND filter appears to be solidly fitted to make it difficult to remove which is a sensible build idea.

No. The only filter you need all the time is the ND. The continuum will bring out more detail and the polarising filter will turn down the brightness, if you want. 

[LukeSkywatcher]

4 hours ago, AdeKing said:

The ND filter is fitted internally and is non-removable in the Lunt wedge, at least it is on mine.  

.........well as non-removable as it can be without a significant amount of effort involving an oil filter strap wrench anyway ?.

Insomuch as it can be removed if you're really really determined.

I bought a 1.25" hw from Germany. Its APM. The ND filter was sold separately. I put it in the wedge and have never removed it. 

CRAZY that they are sold without it by some companies. 

[AdeKing]

2 minutes ago, TSRobot said:

Oh yes yes it has. All spotless and well packed. 

The Lunt instructions say it MUST be used with the polarising filter or continuum filter at all times. Is this true?

The ND filter appears to be solidly fitted to make it difficult to remove which is a sensible build idea.

From reading another thread (below) I don't think a polariser or solar continuum is a requirement with a Herschel Wedge (see the posts from @Merlin66 and @johninderbyon the first page of that thread).  The ND3.0 filter is however an absolute necessity for visual which is why it is non-removable in the Lunt wedge.  The continuum filter or polariser increase contrast and make viewing much more comfortable and I always use one or the other as I have sensitive eyes and find the view uncomfortably bright without.

On 15/08/2018 at 09:54, Merlin66 said:

No additional filters are required with a Herschel wedge - this should be fitted with the ND3 already.

A continuum filter will improve the contrast. OIII filters has also been used with success.

[AdeKing]

1 minute ago, LukeSkywatcher said:

I bought a 1.25" hw from Germany. Its APM. The ND filter was sold separately. 

CRAZY

Yes, some wedges either don't include them or have removable ones.  

I also have the 2" Lacerta Herschel Wedge.  The reason I got the 2" version is that the filter is fitted inside the wedge (though is removable), but with the 1.25" version of the same wedge a loose 1.25" ND3.0 filter is supplied which needs to be threaded into the base of the eyepiece.  I figured that the chances of me forgetting to do that were too high so adopted the cautious approach.

I later got the Lunt, which is significantly lighter and as I said above has an internal filter that you need to be pretty determined to remove.

I don't image but I think that if you are imaging then lower ND filters can be used and the Baader Cool Ceramic wedge comes in two versions, one for visual and one for imaging, the latter of which includes more filters to allow faster exposures.  Note the warning on the Baader website.

https://www.baader-planetarium.com/en/baader-cool-ceramic-safety-herschel-prism.html

I was told NEVER use anything but an ND 3.0 for visual. 

[Stu]

My understanding is that whilst not dangerous, the image without either Continuum or Polarising filter is still uncomfortably bright for visual, so I always use the Continuum in mine (plus ND3.0 of course)

[John]

18 minutes ago, Stu said:

My understanding is that whilst not dangerous, the image without either Continuum or Polarising filter is still uncomfortably bright for visual, so I always use the Continuum in mine (plus ND3.0 of course)

Thats my understanding as well and how I use my Lunt 1.25" herschel wedge. I always use the polarising filter on the end of the eyepiece barrel so that I can turn it (the eyepiece) to control the brightness of the image. I find that this control of brightness is really required for comfortable viewing.

 

[wookie1965]

I use the 1.25 herschel wedge with my Tal 100rs and a Celestron 8-24 zoom here are a couple of pictures.

[TSRobot]

Tons and tons of very useful advice from folks experience. The sun's gone down now. Hope for some sun on Saturday then.  Cheers. ?

[LukeSkywatcher]

3 hours ago, Stu said:

My understanding is that whilst not dangerous, the image without either Continuum or Polarising filter is still uncomfortably bright for visual, so I always use the Continuum in mine (plus ND3.0 of course)

The wedges themselves are already polarized, so strictly speaking you dont really need this filter at all. I dont find the Sun too bright, so i can take or leave my variable polarizing.

The solar continuum filter turns the Sun neon green. It takes a little getting used to but then your brain settles down and you dont notice it. I didnt think id use my continuum, but they do make a difference. 

You may want some kind of Sol finder because the Sun can be tricky to locate. I use the shadow method.

[TSRobot]

I use the shadow method too with my regal. It takes a couple of tries and low magnification, but works ok for me.

[John]

35 minutes ago, LukeSkywatcher said:

The wedges themselves are already polarized, so strictly speaking you dont really need this filter at all. I dont find the Sun too bright, so i can take or leave my variable polarizing.

 

Light comes though the wedge polarised in one plane I believe so adding a further single polarising filter to the eyepiece barrel gives you control over how much light is transmitted to the eye.

 

[Stu]

32 minutes ago, LukeSkywatcher said:

The wedges themselves are already polarized, so strictly speaking you dont really need this filter at all. I dont find the Sun too bright, so i can take or leave my variable polarizing.

The solar continuum filter turns the Sun neon green. It takes a little getting used to but then your brain settles down and you dont notice it. I didnt think id use my continuum, but they do make a difference. 

You may want some kind of Sol finder because the Sun can be tricky to locate. I use the shadow method.

The light coming from the wedge is polarised, agreed, but that doesn't affect the brightness unless combined with a polarising filter which then blocks a varying amount of light depending on the relative alignment between the two.

The wedge itself reduces the intensity by 95%, and the ND3.0 by a factor of 1000 which makes things safe. Obviously everyone is different, I just know that even with the Continuum filter added the grass turns purple when I look away from the eyepiece, so I'm sticking with the additional filters, necessary or not.

[LukeSkywatcher]

27 minutes ago, Stu said:

The light coming from the wedge is polarised, agreed, but that doesn't affect the brightness unless combined with a polarising filter which then blocks a varying amount of light depending on the relative alignment between the two.

The wedge itself reduces the intensity by 95%, and the ND3.0 by a factor of 1000 which makes things safe. Obviously everyone is different, I just know that even with the Continuum filter added the grass turns purple when I look away from the eyepiece, so I'm sticking with the additional filters, necessary or not.

When i bought my APM wedge (which has the Lunt Cactus logo on it), there was very little info about it. It didnt say that the ND3.0 was sold separate. It didnt say the wedge was already polarized (to a certain degree). 

Because the wedge is polarized, you only need a single polarizing filter. I bout the variable.

Them there those Continuum filters are not cheap. 80 euros i paid. 40 euros for the ND3.0 and 40 euros for the variable polarizing.

Wedge cost 140 euros. The filters were more expensive.

Nothing about observing the Sun comes cheap, apart from Astro film.

"but that doesn't affect the brightness unless combined with a polarising filter which then blocks a varying amount of light depending on the relative alignment between the two"

True. I couldnt tell if my wedge was polarized of not until i tried it with the variable filter. It may have been slightly darkened. Not by much.

You (Stu) were a great help when i was buying my wedge and i thank you for it.

 

[wookie1965]

I always use a single polarising filter with mine.

[LukeSkywatcher]

3 minutes ago, wookie1965 said:

I always use a single polarising filter with mine.

I would have only bought a single polarizing filter but got a variable because i didnt know the wedge was already polarized.

[RT65CB-SWL]

I have just given my s/h Lunt 1.25" its firstlight about sixty minutes ago. 

I could not be bothered to get the Giro or Vixen out, so attached my TeleVue Ranger + 15mm Plossl e/p to my camera tripod & ball head as in the photo. My ultimate lightweight grab'n'go.

No sunspots today though!

[TSRobot]

Can't wait to get mine out too. Fingers crossed for sun and spots on Saturday. ?