Narrowest 393.37 ever by Apollo Lasky

Frankenscope? Let's see it!***be advised that NOTHING in this forum has been safety tested and you are reading and using these posts at your own peril. blah, blah, blah... dont mess around with your eyesight when it comes to solar astronomy. Use appropriate filtration at all times...
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Re: 393.4 bp0.1 - yes it does exist.

Post by TheSkyBurner » Tue Sep 11, 2018 6:39 pm

tiny teaser - no tuning. no processing. I will only be showing animated frames without processing. This is the only real representation, single processed images are worthless.

Comparison will never be equal because not all filters are equal. processed images are a personal ability not a comparative, everyone will always have different results. That is life.

This is not a coronado filter. This is not a lunt filter. Comparing these two proves nothing; these are merely a controlled variable, it is not an industrial standard.

I captured this before the tree obscured the view. More will be posted later, please be patient because this is going to take many hours in regards to downloading, seperating frames / converting to .gif , uploading, and changing tuning from 0 degrees to maximum tilt.

90mm x 800mm F/8.8 meade. Basler 1300-30gm

aia1700 -sdo
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Re: 393.4 bp0.1 - yes it does exist.

Post by TheSkyBurner » Tue Sep 11, 2018 7:05 pm

preparing special curve to enhance limb brightness while maintaining surface contrast (gimp)
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Do you see the extremely long filament path carved to the bottom right?
do you see the filament coming out of the active region? zero processing, zero tuning.

Both filament as seen on aia071 sdo; Yes, it is there. Confirmed. Looks like the Chroma filter is doing something that the coronado filter and lunt filter cannot, and I havent even begun to get started! $25.00 telescope objective......

filament aia0171.jpg
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Re: 393.4 bp0.1 - yes it does exist.

Post by TheSkyBurner » Tue Sep 11, 2018 10:47 pm

alright, i have tons of data from today. But first, a little thought for everyone here and all the negative messages posted against me and for all those who banned me and tried to cut me out of my own project.

I just want to say, to anybody that has any problem with me. You can just keep being a lame troll your entire life.


This is my redemption in proving you all wrong, "the experts". You should all be ashamed of yourself's and being so stubborn. I WIN. YOU LOSE.

Stephen Ramsden had the right idea. Share everything, not for profit. Kill your ego, and place trust in others.

SKYBENDER. SKYBENDER. SKYBENDER. SKYBENDER. SKYBENDER. SKYBENDER. SKYBENDER. SKYBENDER.

:bow2
.




APOLLO LASKY www.393nm.com - I wanted teammates, I shared everything and all I got back was trash.

MARTIN WISE: You are a Pillar of the astronomical community. Stay positive! :movie

Chroma 402.15x Chroma 3933.7 1 angstrom filter. Garbage meade 90 x 800 telescope. standard focal reducer

Calcium prominences and spicule layer,
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Re: Narrowest 393.37 ever by Apollo Lasky

Post by Bob Yoesle » Wed Sep 12, 2018 1:38 am

Unfortunately I can no longer rely on Bob Yoesle to correctly use this filter if he is not going to install it in the Skybender.
I plan to do just that in the coming week or so. I will have the Baader Blue CCD filter, KG3, Badder K line, followed by the CT393.34 0.1 correctly oriented in my Skybender, followed by filters to knock down the brightness. I'm not so much interested in the f25 with a barlow, and a collimator system is frankly also a no go as one is not required for the CaK filters form Coronado or Lunt, but I will try f 25 it if the seeing allows. Weather is increasingly becoming an issue here in the Pacific Northwest.

I work full-time in a stressful career (I'm a paramedic) -- and this is what having a bad day means for me:
KIMA.jpg
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At times means I have to take a break from the rest of the world, so a little patience would be appreciated... but I will get to it.

Just getting off my second 48 hour shift in 5 days...
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Re: Narrowest 393.37 ever by Apollo Lasky

Post by TheSkyBurner » Wed Sep 12, 2018 3:13 am

I understand completely bob, I have not ruled you out of the picture and you are highly credible. I just have to get the ball rolling on my end,

Life is not easy for anybody!


On the bright side of things, the sun is always shining on us all whether we get to see it or not. Magnetically connecting to each and everyone of us equally.

Zero reflections!



Forgive the 14.1mb file size, I have no other way to do this.

Everything is there as it should be for a calcium filter, even the filament just above the active region is showing up at f6.5; which is just unheard of.
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Last edited by TheSkyBurner on Wed Sep 12, 2018 3:45 am, edited 1 time in total.

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Re: Narrowest 393.37 ever by Apollo Lasky

Post by TheSkyBurner » Wed Sep 12, 2018 3:38 am

crude Tuning demonstration.
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Re: Narrowest 393.37 ever by Apollo Lasky

Post by TheSkyBurner » Wed Sep 12, 2018 3:39 am

crude tuning demonstration continued
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Re: Narrowest 393.37 ever by Apollo Lasky

Post by TheSkyBurner » Wed Sep 12, 2018 3:40 am

crude tuning demonstration continued 3
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Re: Narrowest 393.37 ever by Apollo Lasky

Post by TheSkyBurner » Wed Sep 12, 2018 4:26 am

single frame tuning.
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Re: Narrowest 393.37 ever by Apollo Lasky

Post by MalVeauX » Wed Sep 12, 2018 12:22 pm

Very interesting! Limb proms are my favorite thing to image, so this is looking great for CaK proms!

Very best,

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Re: Narrowest 393.37 ever by Apollo Lasky

Post by krakatoa1883 » Wed Sep 12, 2018 5:16 pm

Nice to see these results. How does it perform behind a ND 3.8 astrosolar foil or a Herschel wedge ? Thanks.
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Re: Narrowest 393.37 ever by Apollo Lasky

Post by marktownley » Wed Sep 12, 2018 7:30 pm

Good results Apollo!
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Re: Narrowest 393.37 ever by Apollo Lasky

Post by TheSkyBurner » Fri Sep 14, 2018 8:53 pm

Okay guys i had to get this information out before i leave. I just increased prominence transmission by 25%. A fixed 6 degree tilt on the chroma et402.15x filter is absolutely the perfect compliment for this entire system to function. No baader planetarium erf was used, just a kg3 in front of everything.

This will work flawllessly with valerys aries full size derf filter, so have fun!

This is 90mm x 800mm native f8.3, no other optics! basler 1300-30gm ccd (a better camera = even brighter proms!) :hamster:
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And as seen overexposed from the paris meudon spectroheliograph!
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Last edited by TheSkyBurner on Fri Sep 14, 2018 10:49 pm, edited 1 time in total.

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Re: Narrowest 393.37 ever by Apollo Lasky

Post by Bob Yoesle » Fri Sep 14, 2018 10:30 pm

Had another chance to try some imaging before the weather deteriorated. The imaging train consisted of a Orion ED100/900, Baader Blue CCD and KG3 for ERF duties, Baader K line used as a blocker, a ND 0.6 for image brightness control, and finally either the PST CaK or CT 393.37 0.1 filter. All images taken with a PGR Chameleon with FireCapture at zero gain ("160"), gamma set at 1000, and Histogram min ~ 5 and max ~ 175. Aligned, stacked, and wavelet processed identically with RegiStax 6.

PST @ 1.258 ms:
140918 PST no tilt.jpg
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CT 393.37 w no tilt @ 0.871 ms:
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CT 393.37 with tilting that seemed to balance highlight detail with good contrast @ 1.037 ms:
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Not sure the exact amount of tilt which was applied, but this is what it looked like with the Skybender opened after the exposure:
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As Apollo has noted, tilt is required for this filter, and it seems to be approaching a performance level similar the the PST CaK filter. I will be doing some more imaging and evaluation of tilt angle performance changes as soon as the weather improves.
Last edited by Bob Yoesle on Fri Sep 14, 2018 10:42 pm, edited 1 time in total.
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Re: Narrowest 393.37 ever by Apollo Lasky

Post by TheSkyBurner » Fri Sep 14, 2018 10:42 pm

Its party time! Thank you bob! Now We all have to take into account that this is a completely new system design. Something that gets patents and science jounal publications.

Andy lunt didnt just fall backwards onto a compete optical system. I am sure trial and error was a factor for him like it is for us right now in the very beginning of his system building.

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Re: Narrowest 393.37 ever by Apollo Lasky

Post by TheSkyBurner » Sat Sep 15, 2018 4:23 am

sorry guys forgive the crudeness here, this is the first time ive ever tried merging two files, but here are a couple 334 image stacks.
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Re: Narrowest 393.37 ever by Apollo Lasky

Post by TheSkyBurner » Sat Sep 15, 2018 9:20 am

I pointed out these filaments in p_zetners topic on contrast.

Hearing about contrast is getting quite old to me, So if you are wanting to spend 3000$ that is all it takes to get "contrast".

Providing the filaments here at f8.3 should be enough to change the entire imaging scene, but hey what do i know! I didnt spend a single moment in college......
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Re: Narrowest 393.37 ever by Apollo Lasky

Post by marktownley » Sat Sep 15, 2018 5:39 pm

Very good bob and apollo, glad this is working out!
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Re: Narrowest 393.37 ever by Apollo Lasky

Post by Bob Yoesle » Wed Sep 19, 2018 3:58 am

A little better seeing today, so here are my latest test images for the CT 393.37 (used in Skybender tilt unit) - ED100/900, FireCapture set at minimum gain (160), gamma 700, histogram max ~ 190 +/- 10. All used a Baader B CCD and KG3 sub-aperture ERF's. All are 30 sec. captures @ 18 fps, aligned and stacked in Registax 6, best 10%, identical wavelet processing.

CT 393.37 single stack: Baader K line, CT CaK, 0.6 ND, exposure 0.982 ms.
CT.jpg
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PST single stack: Baader K line, PST CaK, 0.6 ND, exposure 1.037 ms.
PST.jpg
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The PST CaK seems to have a slight amount of more detail, but this could be seeing dependent for the particular capture run. Note I used a ND0.6 filter to keep the exposures reasonable for the single stack images, and removed it for the multiple stack images the follow. Once the CT393.37 was tilted for what I felt was the best overall contrast and detail single stacked, it was left that way for subsequent stacking images.

CT/PST double stack: Baader K line, CT/PST CaK, exposure 0.572 ms.
CT PST.jpg
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PST double stack: Baader K line, PST/PST CaK, exposure 0.605 ms.
PST PST.jpg
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There is considerable improvement of image contrast with double stacking, and more detail manifests itself near the solar limb.

CT/PST/PST triple stack: Baader K line, CT PST/PST CaK, exposure 2.217 ms.
CT PST PST.jpg
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A subtle improvement to my eye, and again most visible near the limb...

Apollo recommended trying no Baader K line, PST/CT/PST CaK; the resulting exposure was 1.701 ms. No real change in detail level. The law of diminishing returns appears to be set in for these filters. Double stacking makes an obvious improvement, triple stacking is more subtle, but there.

My overall conclusion from the above is that the CT393.37 is almost identical in contrast performance to the PST CaK filter, and slightly superior for transmission and shortening of exposure times when double and triple stacking (tilting the filter apparently reduced peak transmission). While triple stacking two PST CaK filters with a CT393.37 increases exposure time significantly over double stacking, it does appear to have a subtle increase in contrast. Removing the Baader K line improved (shortened) the triple stacking exposure. Whether or not triple stacking is worth the overall increase in exposure is up to the individual and their local seeing conditions. From Peter's very fine spectroheliograph images it seems it won't be until a narrower profile 0.3 A FWHM filter becomes available that these results might be improved upon.
Last edited by Bob Yoesle on Wed Sep 19, 2018 6:06 pm, edited 3 times in total.
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Re: Narrowest 393.37 ever by Apollo Lasky

Post by TheSkyBurner » Wed Sep 19, 2018 4:28 am

Well done Bob!

okay, the next obvious conclusion. People will rarely be able to buy a CaK PST filter unless someone sells their collection, used.

We can all most certainly conclude that nobody will be offering the pst cak filter new to market ever again and finding a used one, well, good luck! Once they are gone, it will be many moons before you find it again if you dont purchase it immediatley

So it looks like the ct393.37 is the powerful new kid on the block. (all tests were performed at less than F15, and with greater magnification; the higher transmission chroma filter will always win and will continue to improve results further in favor of the chroma.)

Bob:; Try for some prominences with the PST filter, then try with the chroma filter. You will have a difficult time with them using a pst filter, even double stacked... However, they come in every time with the chroma with great intensity!

So now, as concluded by me before even testing anything at all; The pst filter is not tunable and never will be tunable. The Chroma filter is entirely tunable, and achieves remarkable prominence images with a single erf.

Thanks for watching!

Stay tuned for the double pass chroma results, and the first ever amateur 854.2 images.

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Re: Narrowest 393.37 ever by Apollo Lasky

Post by marktownley » Wed Sep 19, 2018 6:35 am

Brilliant!
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Re: Narrowest 393.37 ever by Apollo Lasky

Post by Carbon60 » Wed Sep 19, 2018 11:33 am

Nice work, Bob. Was the seeing fairly consistent throughout the experiment? If at the end of the run you'd have gone back to the 'Lasky' filter as we could call it, would you have seen any difference between the first run with this filter and the last run with this same filter in the same configuration?

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Re: Narrowest 393.37 ever by Apollo Lasky

Post by Bob Yoesle » Wed Sep 19, 2018 5:30 pm

Hi Apollo,

Hoping to get out for another run for prominence imaging this coming Monday the 24th... hoping some prominences will cooperate !-)

Hi Mark,

Brilliant no - just results of being a bit obsessive compulsive ;-) As you know, one must reduce the variables as much as possible, and it's impossible to compare random images taken by others. You have to control for using the same equipment and processes in order to do valid and reliable comparisons and evaluations.

Hi Stu,

The seeing was pretty consistent, and I don't think another run would change the overall results. These results are also pretty consistent with my previous runs with the filters. Of course following double-blind testing methods and more data points - and others doing the evaluations - would help make it most definitive, but so far the direction is pretty clear.

As with any narrow band filter, the CT393.37 would likely do better with a longer f-ratio light cone, or in a collimated or optimized telecentric configuration. I tried ~ f25 with my Klee 2.8 x barlow, but couldn't get the system I kludged together to come to focus. That being said, my intention was to see what it would do in comparison to the PST filter(s) I use in the same configuration I usually employ (ED100 at f9), and how well a triple stack configuration would perform. As the PST filters are no longer available, it would be nice to do a comparison with the Lunt CaK filters instead.

From these results I now know that triple stacking filters - at least for me - offers some additional improvement for CaK, and if all can be optimized through tilt, spacing, ancillary filters, and exposure - may become my new standard for CaK imaging. Whether or not the CT 393.37 can hold its own with a Lunt CaK filter (or how well Lunt CaK filters perform in double or triple stacking) is going to be a question someone else may have to evaluate.

Yet to be evaluated is quad stacking (I may have an answer to this relatively soon), and if anyone would be able to do similar comparisons and stacking with the Lunt CaK filter(s).

Again, thanks to Apollo for making this filter available to the solar community for evaluation.
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Re: Narrowest 393.37 ever by Apollo Lasky

Post by TheSkyBurner » Wed Sep 19, 2018 6:58 pm

It sounds crazy but I could probably get a lunt calcium filter to evaluate with this if I mention that I have a product to enable double stacking and tuning ability to their market. They would be greatly interested in a new product that improves performance much like their anti-reflection filter added on to their DsII filters. I would absolutely love Lunt to endorse the skybender , and I am sure they would be super happy with adding tuning ability their bigger CaK elements.

I firmly believe the real world performance of the chroma filter is entirely dependent on energy rejection. Not sure precisely what Lunt is using but i know its super wide band. I think it is a 400nm full spectrum blocking filter with a pass band somewhere in the realm of 35nm to 50nm.

That being said, I have made available 1nm@pass 393.4; 1.25" and 2" filters ready for purchase. They are too pricey however($600 and $800) for most people to use with the 1 angstrom filters so I opted not to release them for purchase. It would strictly be pro use only. Perfect for energy rejection obviously, but are also +95% transmission. (way too much intensity for pretty much everybody)

The wide band filter's are however $300 cheaper and off the shelf with no custom order necessary, pretty much from any filter manufacturer.. The 402nm filter i use for example, is $350 off the shelf and is a single element solution for lowering the intensity without destroying the onband performance and without resorting to neutral density filters. Also the filter can be counter tilted/clocked to remove any astigmatism and reflective interference created by the tilted 393.37 filter.


I have kept this secret for quite some time, but I do have another calcium system I designed completely off the shelf. Nothing custom at all and you can get it in 50mm if you have disposable income!
It still requires a skybender to use however. Remember, Ive been doing this research for 6 years now...
.

https://www.semrock.com/FilterDetails.a ... 2-830RU-25
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Re: Narrowest 393.37 ever by Apollo Lasky

Post by bart1805 » Wed Sep 19, 2018 8:54 pm

Thanks Bob and Apollo!
So the Lasky CaK seems to behave almost the same as a PST CaK. With indeed the big difference that if I wanted to buy a PST CaK I would have to be very lucky to be really able to buy one. The Lasky CaK costs about 1.300 dollar and requires tilt. So a Skybender would be necessary. Are they for sale Apollo?
A Baader Blue and KG3 can be used instead of the 1NM Chroma filter as Erf. Or as Apollo pointed out you could use a 402 NM filter.
Am I correct?

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