Quark Chromosphere Blockfilter Mod

[Dennis]

Hi there,
i was wondering if somebody successfully found a replacement to the standard Quark 12mm Blockfilter/ITF etc. that would give more light throughput?
What needs to be considered here?

Regards
Dennis

[rsfoto]

Hi there,
i was wondering if somebody successfully found a replacement to the standard Quark 6mm Blockfilter/ITF etc. that would give more light throughput?
What needs to be considered here?

Regards
Dennis

Hi Dennis,

I do not know if it gives more light but since years, after my ITF was rusted again, I just put a 12nm H-alpha filter in place. As far as I know this is not recommended for visual but photographically it works trouble free.

Maybe take out the ITF, make the hole bigger and get a 1.25" H-alpha filter from ¿Astronomik? or any other reliable brand ... Gerd Neuman has excellent service ...

[Dennis]

Hi there,
i was wondering if somebody successfully found a replacement to the standard Quark 6mm Blockfilter/ITF etc. that would give more light throughput?
What needs to be considered here?

Regards
Dennis

Hi Dennis,

I do not know if it gives more light but since years, after my ITF was rusted again, I just put a 12nm H-alpha filter in place. As far as I know this is not recommended for visual but photographically it works trouble free.

Maybe take out the ITF, make the hole bigger and get a 1.25" H-alpha filter from ¿Astronomik? or any other reliable brand ... Gerd Neuman has excellent service ...

Hi Rainer,

thanks, thats exactly the direction i was thinking. And yes, for photographic use only. Energy rejection should be fine with a narrow Baader h-alpha filter placed with a distancer ahead as you said, but i was wondering if this works and shows details on the solar disk like usual. I will try it out, thank you for the tip.

[rsfoto]

Hi Dennis,

Details ?

Look at my images ... There is no ITF but a 12nm Astronomik filter in front of my BF30 ...

[Dennis]

Hi Dennis,

Details ?

Look at my images ... There is no ITF but a 12nm Astronomik filter in front of my BF30 ...

..sounds great, but you didnt notice any changes with lightthroughput? What do you mean with BF30? I think i know.. you are not talking about a Quark filter, but about a Coronado that you use. I want to replace the blockfilter too, because it eats a lot of light. That might be more difficult to do.

[rsfoto]

Hi Dennis,

I used to have a Quark but send all back as I did not get anything out of it.

If I am not mistaken the Quark holes are very tiny. You mentioned something about 12mm and I guess that is what is eating light ... I do not know the focal length you are using your Quark but just make a calculation focal length / 12mm and you get the f/XX and that tells you how much exposure time you need.

Also a Quark is a complete unit containing all. How do you want to change something in the blocking filter ?

A BF30 is a 30mm aperture blocking filter.

[Dennis]

Hi Rainer,
thats right, either a larger blockfilter or a substitution that has a higher transmission. I think both is out of reach for the standard Quark since nobody actually did it. Since there is a 4.2 x telecentric right after the 12mm bf im not even sure if a larger bf would bring more light in.

"Also a Quark is a complete unit containing all. How do you want to change something in the blocking filter ?"

You can take away the bf relatively easy, but it contains also the itf or other parts which im not sure of. So this whole unit would need replacement.

[pawlik]

Changing BF in Quark for bigger version make no sense just becouse built -in telecentric lens has less than 10mm diameter. Also, you can`t use any other typical filter as a replacement of a orignal BF. It will not work.

[Dennis]

Changing BF in Quark for bigger version make no sense just becouse built -in telecentric lens has less than 10mm diameter. Also, you can`t use any other typical filter as a replacement of a orignal BF. It will not work.

Thats what i thought. Thanks.

[marktownley]

Changing BF in Quark for bigger version make no sense just becouse built -in telecentric lens has less than 10mm diameter. Also, you can`t use any other typical filter as a replacement of a orignal BF. It will not work.

Thats what i thought. Thanks.

It does make sense if you mount it higher in the light cone as it will spread thermal load more.

[pawlik]

Changing BF in Quark for bigger version make no sense just becouse built -in telecentric lens has less than 10mm diameter. Also, you can`t use any other typical filter as a replacement of a orignal BF. It will not work.

Thats what i thought. Thanks.

It does make sense if you mount it higher in the light cone as it will spread thermal load more.

Yes, that`s why i chose larger version of BF when I had to replaced it.

[marktownley]

Same here!

[AndiesHandyHandies]

Hi

The advantages of using a Quark Combo are that the telecentric goes before it so spreads the light out more over the 20mm filter. With my 90mm F6.7 and a 3x VK and a 2x ES the input to the 3x VK just fits the first lens aperture, and the output from the 2x ES is over 20mm (40mm) and fully illuminates the output lens.

Also Pupak says the blockers work better in a telecentric beam like the etalon does.

See my recent ERF safety thread in the Mods section for BBE (Looking up at the Suns image) temperatures measured out of the back of the diagonal, 3x VK and 2xES on a 90mm F6.7. An extra Red 25a in the front of the combo body was at 22C.

Also with a blocker the only light coming out of the back of the etalon is one fingers worth of the etalons output cone.
You HAVE to use the right sort of blocker for your etalon.

The narrower the deep sky h-alpha is the lower the peak output is. So I am using a StL Optolong? 40nm red after a UV-IR and before a KG3. for full spectrum blocking. The 40nm red looks a bit like my Lunt red IR blocked ERF. For most light use a Red CCD 100nm filter possibly. I will visually test the difference.

After a while in the sun measure the temperature of the blocker filters front. 40C or less should be OK. A Quark runs at about 40C anyway.

Peter Drew has used a 6" PST mod visually for years without any extra ERF.

Rogerio Marcon uses a 8" Zeiss for imaging with just a chunk of alloy with a small hole in it.

Searching for melted PST Mod or Quark shows no returns.

Cheers. Andrew.

[mdwmark]

WAIT WAIT!!!!!
AM I reading this right.
You want to remove the 12.5mm filter that is in front of the telecentric?
That filter is the blocker that blocks the etalon so you only have one peak coming through. It also blocks all the light you don't want from 300nm to the far IR. You can get a replacement from Andover. The part # should be 656FS02-12.5. It is a 1nm two cavity at 656.3nm wavelength. It is in there standard bandpass filters section. You can't replace it with an 12nm filter and expect it to work.
They may even have them under there surplus catalog
There design putting that standard blocker does shorten the life of the blocker. Because of the amount of heat it is getting. But is cost less then using a 25mm one with the filter stack.
Mark W.

[AndiesHandyHandies]

Hi Mark,

RS Photo made a post which was ambiguous, and I think was really about using a 12nm as an ERF. Which Dennis I think took as about the Quark blocker.

You say the Quark blocker goes to the far IR so does it mean that I do not need a KG3 in my internal ERF stack?
I have asked about the filter several times on here but no one seems to know. And no full bandwidth chart I have seen.

I have the 4.2x and Combo versions both Second hand. The latter without the off-axis adapter.

I assume that limiting the temperature of the blocker filter to 40C with pre-filters will prolong its life.

I am using the Combo at F40 for visual. Someone said at F35 and over you do not need an ERF, I presume because the large image scale keeps the energy intensity down, possible a comment about imaging which most people appear to do.

Thanks. Andrew.

[AndiesHandyHandies]

Hi

Raniers comment is in this thread. And should certainly not be taken as something to do for visual use.
And he still has the rusted blocking filter in the Quark?

Will not letting 12 combs out of the etalon decrease contrast even though its brighter?

Cheers. Andrew.

[AndiesHandyHandies]

Hi

" There is no ITF but a 12nm Astronomik filter in front of my BF30 .'

Seems confusion about names for Etalon Comb trim / blocking filters possibly. Across different manufacturers.

And this is about non-quark set up where he is using a Coronado BF30. And the 12nm as an ERF infront of the BF30.
He sent a Quark back or gave up on it.

There should be a sticky post about safety with a section for each vendors set ups using a cross-reference to a standard term for each component.

Cheers. Andrew.

[Dennis]

Thank you guys, as far as i understood in mid April there is no other blocker alternative to the Andover replacement part.
Also i read out of the posts that there has been no transmission improvement of this blocker since the release of the Quark filters.

Questiones have been answered, thx.
Dennis

[christian viladrich]

Hi Mark,

You say the Quark blocker goes to the far IR so does it mean that I do not need a KG3 in my internal ERF stack?
I have asked about the filter several times on here but no one seems to know. And no full bandwidth chart I have seen.

Thanks. Andrew.

Hello Andrew,
If you go to this page :
https://www.andovercorp.com/products/ba ... 600-699nm/

You can check the characterics of the blocker used in Quark filters (check reference number given by Mark W):
Blocking : 1x10-4 avg. X-Ray to FIR

Andover sent me the transmission profile around Ha (red curve) :
http://astrosurf.com/viladrich/astro/in ... spaced.jpg

The characteristics given by Andover are very reliable. All Andover filters I measured are exactly as measured with Andover spectro. No bad surprise there.

You can find a better blocking filter at Alluxa (ref Alluxa 656.3-1_OD4_7018) : 3-cavity filter instead of 2-cavity, > 80% peak transmission instead of 45%, hard coated instead of soft coated. But of course it comes to a cost. There is no free lunch.

[AndiesHandyHandies]

Hi Mark,

You say the Quark blocker goes to the far IR so does it mean that I do not need a KG3 in my internal ERF stack?
I have asked about the filter several times on here but no one seems to know. And no full bandwidth chart I have seen.

Thanks. Andrew.

Hello Andrew,
If you go to this page :
https://www.andovercorp.com/products/ba ... 600-699nm/

You can check the characterics of the blocker used in Quark filters (check reference number given by Mark W):
Blocking : 1x10-4 avg. X-Ray to FIR

Andover sent me the transmission profile around Ha (red curve) :
http://astrosurf.com/viladrich/astro/in ... spaced.jpg

The characteristics given by Andover are very reliable. All Andover filters I measured are exactly as measured with Andover spectro. No bad surprise there.

You can find a better blocking filter at Alluxa (ref Alluxa 656.3-1_OD4_7018) : 3-cavity filter instead of 2-cavity, > 80% peak transmission instead of 45%, hard coated instead of soft coated. But of course it comes to a cost. There is no free lunch.

Hi,

Thanks for the reply.

I had a hard time on their site due to my many blocking apps.
Thanks for sharing the curve.

So I can remove the KG3 from my Quark set up internal ERF stack safely for visual use?

Is there a temperature on the blocking filter you should stay under to prolong its life? I have assumed 40C would be OK as the etalon is heated to about 40C.

So Dennis can get a brighter image at as you say a cost.

On my 90mm F6.7 working at F40 at the Combo Quark entrance is an ERF needed in terms of eye safety when observing for a session? I understand that may reduce the blocker life. I have tried a UV-IR, then that and a 40nm red and then the KG3 as well and visually no brightness difference.

Would a 100mm or 40mm red dichoric filter give safety blocking filter wise, give decent h-alpha brightness, and have a cool enough beam when no diagonal in for occasional flashes in the eye?

Player One I see do sell essentially a RED rgb filter as an ERF at 1.25". Interms of flatness are the Baader CCD rgb filters, or similar, the best?

Cheers. Andrew.

[marktownley]

You can find a better blocking filter at Alluxa (ref Alluxa 656.3-1_OD4_7018) : 3-cavity filter instead of 2-cavity, > 80% peak transmission instead of 45%, hard coated instead of soft coated. But of course it comes to a cost. There is no free lunch.

That's a nice filter Christian, and would work very well too. But, like you say, no free lunch!

[Dennis]

You can find a better blocking filter at Alluxa (ref Alluxa 656.3-1_OD4_7018) : 3-cavity filter instead of 2-cavity, > 80% peak transmission instead of 45%, hard coated instead of soft coated. But of course it comes to a cost. There is no free lunch.

That's a nice filter Christian, and would work very well too. But, like you say, no free lunch!

Yes.. that transmission curve is a beauty. A good bf for creating a ds setup.

[mdwmark]

Hi again,
There are somethings I would like to clear up on this discussion.
OK ,on the original Quark they used a standard 12.5 diameter, 1nm , 656.3nm from Andover. This filter the bandpass and the ITF/RG630 are cemented together and mounted in a ring. This should be a stocked part for them. There would be no reason to add an KG5 with this, the only thing it will do is drop the brightness of the system because it only transmits 60% at Ha. It would be like adding another ITF( they transmit 60% ). If they want to call the front blocker an ERF also that fine. But you can't just replace it with something much broader and not blocked to the far IR.

Christian is right about the Alluxa filter. But it is only blocked to 1200nm. This would need a KG5 filter somewhere before the eyepiece to block the IR light. So you will loose some more light but, this still has better transmission then the standard design. But then there the cost, you can replace the standard filter more then once for what the hard coated cost. In the pass a standard blocker had a 1 year warranty from the manufacturer. This was a standard regardless which company made it. I see that now Andover has increased there warranty to 5 years. This is a easy fix something you can do yourself. I have no idea what Daystar warrant the Quark blocker for, so I can't say they will replace it .
There was also something that the filter runs at 40C. This would not be what the front mounted blocker of an Quark would be at. I attached an white paper about that..
My concern is that people under estimate what will work and what will not work when it comes to the blocking needed for a solar Ha filter.
Mark W.

The effects of temperature on a standard blocker A1.pdf

(188.59 KiB) Downloaded 76 times

[marktownley]

Sage information as always, thanks Mark

[AndiesHandyHandies]

Hi

4.2X fronted Quark.
The 12.5mm blocker on the front is seperated from the Quark body. So we need to control the temprature with pre-ERF. And in warmer climates would need active cooling to keep it down to 20C?

Combo Quark.
The 21mm blocker is mounted directly on the Quark front, so I assumed a 40C limit as that is what my Quark etalon is heated to. But we still need to control extra heating with a pre-ERF if measurements of the blocker temperature in normal use goes over 20C.

Thanks for the paper on temperature sensitivity of the Quark etalon passband.


Now my question about the Quark bandwidth has been answered then we do not need a KG3/5 after the Quark, as the Quark blocker has protection into the far IR. For visual and imaging.

So you are saying the Quark does not need pre-blocking over 1200nm as the blocker will reflect that?

Also its often stated internal dielectric ERFs should go far up into the OTA. Minor point is that the reflected hot-spot is well out of the scope. For family or public use and extended guard should be used to stop access, 1" gavanised square mesh?

To benefit from the Quantum fruity-loopery of the workings of a dielectric filter it should not go up the tube further than it would allow the whole beam not to fall on the filter glass (es). Check by moving the image from side to side the maximum you use the image plane. In that case as I have shown the internal components are not much above ambient.

Thanks Andrew.