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Have an APM/Lunt Hershel Wedge: Need Filters.


LukeSkywatcher
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Sorry to hash this out once again, but i really do NOT want to take any chances with my eyesight while solar observing.

A couple of weeks ago i bought an APM/Lunt Hershel wedge from a company in Germany. It cost the guts of 200 quid (just for your own reference). I thought that it came with the needed filters (ND3.0 and polarising). 

When i hold the wedge up to a window, the brightness outside is dimmed, but not too much (its a nice dimmed view). When i hold it up to the tv from a distance............i can almost see nothing. The inside of wedge mirror (with the naked eye) is nice and dark and smoky grey. Is this normal?. Does this mean that an ND 3.0 filter has been pre-installed?.

All this aside, I know i need an ND3.0 filter (unless its already built in), a solar continuum filter and a polarising filter.

My question is..............can anyone here point me in the right direction for all 3 filters i need assuming i want to buy from FLO. I have checked their site and am unsure of which filters to buy.

I wont be buying for about 6 weeks, so no rush. I really just want to buy all filters in one go.

Thanks in advance.

Paul. 

P.S.~~ i should mention all filters i want should be in the 1.25" format. I'm thinking i can get them all for about £100?.

Edited by LukeSkywatcher
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Paul, you can check if the ND3.0 is installed. It should be visible down the eyepiece side of the wedge. You can unscrew the eyepiece holder and will be able to see the filter installed (or not)

In terms of the other filters required, you don't strictly need both. You can use either on their own, or both together.

These filters go into the eyepiece barrel itself, and the benefit of the polariser is that rotating it adjusts the brightness level to tune the contrast.

I just use the continuum in its own, and find it excellent.

Stu

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Hi Paul

As mentioned by pm if you can see the prism in the bottom of the eyepiece holder you don't have an nd3.0 fitted.

Flo sell the Baader solar continuum and any variable polariser will be ok.

Personally I recommend all three but any two including the nd3.0 is safe.

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Hi Paul

As mentioned by pm if you can see the prism in the bottom of the eyepiece holder you don't have an nd3.0 fitted.

Flo sell the Baader solar continuum and any variable polariser will be ok.

Personally I recommend all three but any two including the nd3.0 is safe.

I know there is a prism in the wedge. Its visible but blackened/grey. 

Upon further reading..............the wedge blocks 95% of light and heat. An ND 3.0 filter wlil block the last 5%?

I wont take any chances. I want all 3 filters. Can i buy them from FLO?. If so can you please link to them.

ND3.0,solar continuum and polarising.

Thanks in advance. Sorry to be a pain in the behind.

Edited by LukeSkywatcher
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The ND3.0 reduces the final 5% by a factor of 1000, making it safe, but still too bright for visual. The continuum and/or polarising filter do the rest.

Have you checked if the ND3.0 is there? From the sounds of it being 'blackened', I suspect it might be. Maybe post some pictures up so we can compare?

I can't link to FLO at the moment, the site is not responding, will do in the morning

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The ND3.0 reduces the final 5% by a factor of 1000, making it safe, but still too bright for visual. The continuum and/or polarising filter do the rest.

Have you checked if the ND3.0 is there? From the sounds of it being 'blackened', I suspect it might be. Maybe post some pictures up so we can compare?

I can't link to FLO at the moment, the site is not responding, will do in the morning

I also suspect that the ND3.0 filter is built in. I'll try to take a couple of images looking down into the prism. There is really not much to see. The view is not like a standard star diag or prism. It is smokey grey.

Edited by LukeSkywatcher
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Beloptik makes nice equipment and this filter might work well. A quick email to Oliver will answer any questions, he is very helpful. http://beloptik.de/en/left/ircut-pol-nd-filter-1/ The ND3 is mandatory. The SC works extremely well IMHO. This is Baaders version that I have, without the SC they recommend more ND.

post-30641-0-77610700-1423610531.jpg

Edited by jetstream
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Okay, Luke.

I've just taken some photos of my Lunt Wedge. Hopefully, they will go some way in giving you a hand to check over your own wedge and again, hopefully they will offer you a little piece of mind:

The Wedge

post-21324-0-07493600-1423614544_thumb.j

Bird's eye view down the eyepiece-end of the wedge. The tinted blue glass is the ND 3.0 filter.

post-21324-0-42438500-1423614799_thumb.j

The Wedge with the scope-end barrel unscrewed

post-21324-0-36136900-1423614616_thumb.j

Inside the Wedge. To the left you can see the ND 3.0 filter screwed in place. To the right is the wedge's mirror. If you don't have that filter to the left, you need to buy it!

post-21324-0-70771800-1423614854_thumb.j

Needless to say, before using the wedge for the first time, I rang Lunt and double checked that what I was seeing was really the ND 3 filter. Better safe than sorry. 

Hope this helps :grin:

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Okay, Luke.

I've just taken some photos of my Lunt Wedge. Hopefully, they will go some way in giving you a hand to check over your own wedge and again, hopefully they will offer you a little piece of mind:

The Wedge

attachicon.gifLunt 1.JPG

Bird's eye view down the eyepiece-end of the wedge. The tinted blue glass is the ND 3.0 filter.

attachicon.gifLunt 3.JPG

The Wedge with the scope-end barrel unscrewed

attachicon.gifLunt 2.JPG

Inside the Wedge. To the left you can see the ND 3.0 filter screwed in place. To the right is the wedge's mirror. If you don't have that filter to the left, you need to buy it!

attachicon.gifLunt 4.JPG

Needless to say, before using the wedge for the first time, I rang Lunt and double checked that what I was seeing was really the ND 3 filter. Better safe than sorry. 

Hope this helps :grin:

Thanks for this Quilia. Birds eye view i dont see any blue. Also i dont see any filter screwed into place to the left. 

Very much appreciated.

Edited by LukeSkywatcher
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Pretty much sorted, then. At this junction, it is reasonable to conclude that you don't have the ND 3.0 filter but this really isn't such bad news. Give APM a ring and see if you can do some deal with them and if not, no worries, you've done your eyes a big favour and you can pick these filters up relatively cheap in astro-terms.

Glad the pics helped to some extent :grin:

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Looking at the site i bought the wedge from, people who bought the wedge also bought some of these: I'm thinking maybe the ones i have marked with red may be the ones to go for. I'll see if i can do a bit of a deal if i buy all 3 at the same time and mention i am a returning customer. Worth a try.

If not, no worries. Dont know if i dont ask as Moonshane and Qualia said.

post-5361-0-23032700-1423774693.jpg

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They would be fine Paul but do check the nd3 is suitable for visual as I am sure I read that the .0 matters.

I will investigate if the ND3 is for visual or photographic purposes. Also i'll do some some searching to find out the differences between ND3 and ND3.0

Thanks everyone. One thing i wont go cheap on, is my eyesight. I can wait. I am not going to rush into buying filters without being absolutely 110% sure that they are safe.

Edited by LukeSkywatcher
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I'm not convinced about the ND3 filter as above. From the "blurb" i can only think it is a Moon filter:

http://www.astroshop.eu/lunt-solar-systems-1-25-nd3-filter-for-herschel-wedge/p,22942#tab_bar_1_select

The solar continuum and polarising seem fine.

Edited by LukeSkywatcher
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The only one that matters is the nd 3.0. I have the baader one shown. The others just create more contrast and comfort you cannot damage your eyes with the the wedge and correct nd 3.0.

You have the second from left?. It is a 3.0 

What threw me was that its sold as a "light pollution filter" (or at least light pollution is mentioned). 

Thanks Moonshane, i now know what i want/need and feel very confident in my choice.

From left to right in my image, i should go for #1,2 and 4.

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Looking at the site i bought the wedge from, people who bought the wedge also bought some of these: I'm thinking maybe the ones i have marked with red may be the ones to go for. I'll see if i can do a bit of a deal if i buy all 3 at the same time and mention i am a returning customer. Worth a try.

If not, no worries. Dont know if i dont ask as Moonshane and Qualia said.

Done and dusted.

I just bought #1,2 and 4

The ND IS 3.0................thats the main thing. The SC filter cost about twice what the ND3.0 one did.The polarising filter was the cheapest.

In about a week they should be here and i should be somewhat of a solar observer............albeit a white light observer.

I have hung my DSLR on the back of my 70mm scope before (with a heavy duty tripod). So i'm sure i can also be able to image the Sun.

Edited by LukeSkywatcher
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