星河科研社獲邀出任 Daystar Filters 代理

[社長]

特別關注新產品 Quark Ha Eyepiece

http://www.daystarfilters.com/

稍後公佈更多詳情。

[mwtse]

Refractors only?

[David]

Refractors only?

I suggest you buy a big refractor (>9 inch) as an accessory to this eyepiece. Then you can beat this beast:
viewtopic.php?f=14&t=3813&p=24510#p24510

[社長]

Refractors only?

反射／折射射因為光線要在望遠鏡管內來回反射，又貼近管壁，的確很受氣流干擾，影響影像質量。

另外也要考慮ERF的問題。

[社長]

Refractors only?

I suggest you buy a big refractor (>9 inch) as an accessory to this eyepiece. Then you can beat this beast:
viewtopic.php?f=14&t=3813&p=24510#p24510

your beast standard is too low

12" is cute beast.

viewtopic.php?f=12&t=2148&start=20#p22410

40" is real beast.

viewtopic.php?f=13&t=97

[mwtse]

Refractors only?

反射／折射射因為光線要在望遠鏡管內來回反射，又貼近管壁，的確很受氣流干擾，影響影像質量。

另外也要考慮ERF的問題。

還以為是不同波長的光折射後聚焦在不同位置、不會出現散熱問題。

[社長]

還以為是不同波長的光折射後聚焦在不同位置、不會出現散熱問題。

這是從另一個我個人沒考慮過的角度去看散熱問題，不如再詳細分析?

我的理解是這樣的，因為空氣温度並不均勻，便會造成密度變化，影響折射率或光線路徑，干擾了成像。所以就算我們做室內星點測試，測試時只用單色如紅、綠、藍光測試，埃利盤及衍射環的穏定度仍會受各式各樣的散熱源影響，包括走廊是否或過份通風、門口的射燈、鏡筒從辦公室拿出來時待的時間夠不夠，光源及望遠鏡間是否有人走過等等等等。

viewtopic.php?f=14&t=763

viewtopic.php?f=22&t=890

viewtopic.php?f=14&t=744

viewtopic.php?f=22&t=3730

所以若鏡筒內聚焦了明顯高温的光錐(觀測太陽時的入射光線)，那鏡筒內的不同部份空氣密度便會激烈變化，大大干擾了影像的穏定度，其中因為折射鏡的光路不用像反射或折射鏡來回跑兩三次，而光錐離開物鏡後便收窄至焦平面聚焦，開始跟鏡筒管壁保持越來越遠的距離，不像反射或折反射有一個平行光束貼著管壁而行，那受的影響力少一些，因為管壁是管內及管外氣温的介面，很多問題也在那裡發生，而折射鏡不像反射鏡，用大一點的鏡筒並沒有成本問題（副鏡要用大一點，影像對比度）。

[David]

特別關注新產品 Quark Ha Eyepiece

http://www.daystarfilters.com/

稍後公佈更多詳情。

平得有原因，因為要用電加熱去調頻，要等好耐
http://www.cloudynights.com/ubbthreads/ ... ost6464390

---------------
Now a little more about the Quark by Daystar. First off, they tell me it'll be good for imaging. You may have to use a focal reducer to get a full desk and you may have to back up the camera slightly. They had mounted on the 80 mm short refractor that had the dirtiest main objective ever seen in my life. It still had great views. Very even across the entire field. Because of the built-in 4x barlow it fills the eyepiece just about to the edge. Has a heating element in it. That heats it to operating temperature of around 140°. It has an adjuster that dead center is on band and you have five clicks in each direction of adjustment to take a total of .5 Å off band. All etalons operate at slightly different temperatures. Their preset at the factory, so the center position, keeps each etalon on band . Takes 10 min. to warm up. Adjustments take less than 3 min. to take effect after initial warm-up.

[Raymond TSE]

Is it possible to stack Quark Ha eyepiece to existing Lunt 152 and what would be the result ?

Raymond Tse

[社長]

Is it possible to stack Quark Ha eyepiece to existing Lunt 152 and what would be the result ?

Raymond Tse

viewtopic.php?f=22&t=3887

[Raymond TSE]

Any information whether the the heating circuit inside the Quark is :-

1. a single stage (ie just heating up and let it cool down naturally/passively. This process is slow); or
2. dual phase temperature control (ie heating up and then use electric TEC to cool it down. This would be faster).

When it takes 5-10 min such a long tme to heat the etalon to reach on-band/variation of each 0.1A, I guess it may just be single stage heating/passive cooling. But Savio might check with Daystar.

Further, when handphone 5V 1A is not to be used for Quark, why not change to 12V for faster on-band heating/each adjustment of 0.1A.

Expecting Quark II version with faster heating/cooling and may be 3x (instead of 4.2x) teleconcentric.

Raymond

[社長]

Any information whether the the heating circuit inside the Quark is :-

1. a single stage (ie just heating up and let it cool down naturally/passively. This process is slow); or
2. dual phase temperature control (ie heating up and then use electric TEC to cool it down. This would be faster).

When it takes 5-10 min such a long tme to heat the etalon to reach on-band/variation of each 0.1A, I guess it may just be single stage heating/passive cooling. But Savio might check with Daystar.

Further, when handphone 5V 1A is not to be used for Quark, why not change to 12V for faster on-band heating/each adjustment of 0.1A.

Expecting Quark II version with faster heating/cooling and may be 3x (instead of 4.2x) teleconcentric.

Raymond

thanks for your question.

這是新產品，有很多尚要學習，稍後回覆你。

[社長]

Any information whether the the heating circuit inside the Quark is :-

1. a single stage (ie just heating up and let it cool down naturally/passively. This process is slow); or
2. dual phase temperature control (ie heating up and then use electric TEC to cool it down. This would be faster).

When it takes 5-10 min such a long tme to heat the etalon to reach on-band/variation of each 0.1A, I guess it may just be single stage heating/passive cooling. But Savio might check with Daystar.

Further, when handphone 5V 1A is not to be used for Quark, why not change to 12V for faster on-band heating/each adjustment of 0.1A.

Expecting Quark II version with faster heating/cooling and may be 3x (instead of 4.2x) teleconcentric.

Raymond

The Quark only has active heating. The cooling is passive. The Ion filter we make actively cools and heats and is much faster to come on band. The Quark usually takes about 7-8 minutes to warm up. When you change the wavelength up or down it can take a minute or so to adjust.

The Quark was designed for amateur and convenience, hence the 5V USB port and small battery pack. Our Ion and Quantum are designed for professional use with more power (12-20V).

[Raymond TSE]

Thanks Savio for clarifying the inner working of Quark Ha EP with Daystar. My initial guessing is pretty close.

[社長]

The little Quark is not a typical kind of fit for a large SCT telescope. Usually, clients who have these big SCT telescopes use a stop-down aperture reduction instead of full aperture.
This is because the daytime solar radiation degrades the seeing so that usually one can only achieve about 125-150mm aperture seeing.
We usually only see full 10" aperture at professional observatories such as at Canary Islands where there is a big body of water around the observing location to settle the seeing.

Also, the heat that comes from full aperture observing will cause heat gain inside the dark, closed OTA of a telescope even when an energy rejection filter is used.
We can make a full aperture 10" ERF, but it is very expensive.

The Quark is designed for use on a refractor telescope of F/4-F/9.
If it is to be used on the big SCT, then the magnification can result in almost 10,000mm EFL.

Most of our Mewlon 250 clients use our Quantum filters instead of the little Quark style filter.
Also, most SCT owners use an aperture reduction stop-down.
http://www.daystarfilters.com/Configurations/SCT.shtml
Here is our page about Energy Rejection filters for SCT applications.
The Mewlon 250 would use a 90mm clear aperture.
As I recal, the Mewlon 250 is slower focal ratio than other SCT telescopes but the 90mm is all that fits between the secondary and the OD of the OTA.
So if the client prefers larger aperture, it would be possible to increase the clear aperture with a hole that exceeds the 90mm spot.
It would just be shaped strangely with the central obstruction blocked somewhat.

In full aperture energy rejection filters, we always use yellow colored glass (Long pass cut filter) prepared to 1/4 wave.
We have only done one ERF in 10" before in the past. It was for the Vatican Observatory and they had a special mountain top location.
That ERF was $2500 USD.

The Quark has a 4X telecentric barlow inside to bring the light to ~F/30.
With a stop down on the aperture, the client will not need the barlow of the Quark.
It is then better to use an ION or Quantum.
Again, most Mewlon 250 owners use Quantum filters.
The ION will only pass a full disk on telescopes of about 80mm.
Above 80mm, a client would need a Quantum filter to pass full disk at once.

If the client prefers an inexpensive option to try Hydrogen Alpha, the Quark is a good choice, but will work best on a refractor.
If the client is looking for high resolution, large aperture viewing and imaging, then a Quantum may be better suited for their needs.

Here, we can use a UV/IR cut filter mounted to the rear:
http://www.daystarfilters.com/inout_art ... Refractors
A good picture of how the ERF is applied can be seen here:
http://www.daystarfilters.com/inout_art ... -refractor

We plan to have a small SCT telescope version of the Quark available in the fall, but we are not ready to release another yet.

[Raymond TSE]

Dear Savio,

Thanks again for clarifying with Daystar.

The Quark (or even modified PST) will be useful for attaching to large aperture OTA such as :
1. 4 inch ST102 refractor in http://solarchat.natca.net/viewtopic.ph ... 652aaa7633, or
2. up to 9 inch (230mm) F9 refractor in http://solarchat.natca.net/viewtopic.php?f=4&t=11689. The scope owner lives in Southern France and has very good seeing to support the 9 inch refractor.

As Daystar has pointed out in its manual, an ERF is a must on EQ mount for long duration imaging.
As I have a LS152mm Ha/T, it is natural to upgrade a larger aperture OTA instead of getting a 135/160mm D-ERF to my TEC140. Thus Baader's maximun D-ERF 180mm is just 1 inch aperture over 152mm and thus not worth considering.

Daystar has made a good point on seeing which means most of the time the seeing may not support larger aperture beyond 150mm.

But the trend is for Lunt and now Daystar to consider a small SCT Ha scope. In Lunt's case a C8. Not sure the aperture of Daystar but I presume it will also be C6 to C8 range. The telecentric for F10 SCT should be around 3x instead of the present 4.2x

Savio, pls check with Daystar their prices for 8 inch and 9 inch front filter. 1/4 wavefront error is acceptable though not as high as Baader 1/10 wavefront.
Can you also get a transmission curve from Daystar ? Why Daystar use yellow heat absorption glass instead of using IR/UV reflecting coating ?

Raymond Tse

[社長]

Daystar has made a good point on seeing which means most of the time the seeing may not support larger aperture beyond 150mm.

but we see gain of LS230T over LS152T even under suboptimal condition.

of course it worth to setup such a big solar scope to seaside, on a big piece of grassland...etc to enjoy the full power of such aperture.

depending on how much you want to spend, it's possible to custom build a reflector type solar scope, which should be more "affortable" and manageable than 9" or 10" APO, or even a singlet refractor instead of doublet or triplet? See the explanation of LS60T design in 2008.

[Raymond TSE]

I agree that after seeing LS230Ha/T, it is worthwhile to try building a large aperture (bigger than 6 inch plus) solar scope,
especially since the east side of my observatory is a large country park, and about 300 feet from seashore in the west.

If SCT Ha scope is the new trend, I wish to build a front filter on top of C9.25 F10. Either a modified PST or Ha EP at the rear of the scope
would be good match.

But the hurdle is to wait for large ERFs in the range of 8.0 inch to 9.5 inch aperture.

Raymond

[Raymond TSE]

A white mouse has appeared to test LS80 and LS152 trying to double-stacking Quark :-
http://solarchat.natca.net/viewtopic.ph ... 18397cae34

Not a good match.

May have to consider double stacking LS152 with modified PST.

Raymond

[社長]

David 已為他的LS152T 訂了DSII