Lunt Blocking Filter Owners. Your Assistance Please

[bilbo]

Hi Guys

I have an issue with light transmission through a B600 filter

If you own one of these or B400 B1200 could you help with a little experiment, Shine a White light (I used LED) at an angle onto the large scopeside filter so that you can see the reflection and tell me whether the reflected light source  (lamp not glass colour) is white or green.  If you can let me know the scope year (first four digits of S/N or OOOO for late models it would be a great help in narrowing down the issue.

I'll elaborate more later

cheers

Steve

Edited May 19, 2019 by bilbo

[Pete Presland]

Hi Steve, my B600 is green like the left hand image. The serial number is 2014295. Hope this helps.

[bilbo]

Thank you ever so much. another dozen results and I'll be happy and hopefully one step closer.

Steve

[Pete Presland]

4 minutes ago, bilbo said:

Thank you ever so much. another dozen results and I'll be happy and hopefully one step closer.

Steve

It might be worth mentioning it in one of the Solar imaging/Observing sections as well.

[Floater]

Mine is a BF1200 so not sure if this is relevant but scope side is green. S/N 20143040.

Just as extra information, the EP side of my 1200 is red and during a back and fore email conversation with Lunt customer service some time back I was told that the green side should be towards the scope.

Hope you find the answer to whatever it is you seek.

[bilbo]

Thank you, , I don't think the actual model matters, I kept the post short to avoid unnecessary replies, But I will explain all

Steve

[NGC 1502]

 

Hi Steve.  My B400 scopeside filter shows white with LED.  S/N 2010 212.

HTH, Ed.

[bilbo]

Thanks ED

 Would've expected green if my idea is correct, but it still could be.  The more responses I get the easier it becomes to work it all out

cheers

 

[symmetal]

Hi Steve, my B1200 is green. S/N 0001005

Alan

[bilbo]

Wonderful. Thank you, I’m hoping I’ve nailed this. I’ll give it till Monday, the more replies the merrier and the end result could be of use to everyone.

cheers

[JeremyS]

On 17/05/2019 at 18:02, bilbo said:

If you own one of these or B400 B1200 could you help with a little experiment, Shine a White light (I used LED) at an angle onto the large scopeside filter so that you can see the reflection and tell me whether the reflected light is white or green.

Green. 2014218. B600

[AdeKing]

My B1200 scope side filter reflects red/green though the green is not uniform like in your image. 

Serial: 20101259

Edited May 19, 2019 by AdeKing

[Piero]

I am not an expert of this, but I thought that that filter is the ITF not the blocking filter. I thought the blocking filter is the red one on the eyepiece side.

Can someone give more detail, please?

[bilbo]

45 minutes ago, Piero said:

I am not an expert of this, but I thought that that filter is the ITF not the blocking filter. I thought the blocking filter is the red one on the eyepiece side.

Can someone give more detail, please?

Hi  Piero,

Q is just simply about the colour, I'm looking for variations

[Piero]

20 hours ago, bilbo said:

Hi  Piero,

Q is just simply about the colour, I'm looking for variations

Strictly.

[jam1e1]

hi white

b1200 2015

Whilst on this topic noticed this strange mist type cover - any suggestions on what this is - i wouldnt have noticed if didnt do this! J

[bilbo]

1 hour ago, jam1e1 said:

hi white

b1200 2015

Whilst on this topic noticed this strange mist type cover - any suggestions on what this is - i wouldnt have noticed if didnt do this! J

Hi

Filters starting to deteriorate, known problem and apparently free fix from lunt see

https://stargazerslounge.com/topic/316776-lunt-blocking-filter-check-yours-you-wont-regret-it/?tab=comments#comment-3464489

PS try catching the refrection of the actual lamp, I used an led tube lamp for the first pics, and a power tank torch for the second.

cheers

Steve

[bilbo]

Meant to add both blocking filters in pics I posted  have crystal clear filters, I'm trying to discover if there any correlation between the reflection and another problem which is why catching the reflected "bulb" itself is important

[tooth_dr]

On 18/05/2019 at 16:09, symmetal said:

Hi Steve, my B1200 is green. S/N 0001005

Alan

Interesting Alan that my scope is 0001004 and reflects white (although the filter looks green)

White

B1200

[symmetal]

17 minutes ago, tooth_dr said:

Interesting Alan that my scope is 0001004 and reflects white (although the filter looks green)

If you see the light in the reflection it looks more white but if you shine the light at an angle and view it such that the light source isn't directly visible in the reflection it then appears as green. I assumed that's what bilbo wanted, but with his image showing the light itself shown in the reflection, I think I've got it wrong and would have to say it's more white than green. Sorry bilbo. (S/N 0001005)

Alan  

[bilbo]

7 hours ago, symmetal said:

If you see the light in the reflection it looks more white but if you shine the light at an angle and view it such that the light source isn't directly visible in the reflection it then appears as green. I assumed that's what bilbo wanted, but with his image showing the light itself shown in the reflection, I think I've got it wrong and would have to say it's more white than green. Sorry bilbo. (S/N 0001005)

Alan  

Yes, correct, the important thing I'm looking for is the colour of the mirrored reflection of the lamp and not the colour of the glass. I tried four white light led sources with different colour temperatures, 2 were cool white, (very white), 1 Warm (Like the old tungsten bulb) and 1 inbetween. They all produce a distinctively green reflection of the source in the 2013 B600 and a White reflection in the 2017 B600 S/N 0000.

At the moment I'm just trying to gauge if and when there was a change in these filters and if it points to a more concerning issue.  I'll probably have to ask the question again with greater clarity. My next post will explain why

Steve

[tooth_dr]

25 minutes ago, bilbo said:

 

At the moment I'm just trying to gauge if and when there was a change in these filters and if it points to a more concerning issue.  I'll probably have to ask the question again with greater clarity. My next post will explain why

Steve

 

Steve this all sounds ominous. Can you please clarify if there is a concern over safety. 

[bilbo]

No concerns about safety whatsoever,

[NGC 1502]

 

Hello Steve.   This may not be relevant, however a few years ago I read that some of the Lunt blocking filters had suffered a coating failure.  I don’t recall it was a safety issue, more of concern about the quality of the view/image.

I cannot remember where I saw that, but I’m certain I did.   I’m wondering if contacting Lunt with an enquiry may help ?      It’s possible that coating failure could lead to changes to the coating process.

Please disregard this if it’s irrelevant.

Ed.

EDIT -

Please accept my apologies, only just realised the coating failure has already been mentioned.

Edited May 21, 2019 by NGC 1502
Extra information

[JeremyS]

On 17/05/2019 at 18:02, bilbo said:

I'll elaborate more later

Any news on this study? I.e. what your theory is?