Solar Spectrum RG 0,4x Telecompressor 2".
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Solar Spectrum RG 0,4x Telecompressor 2".
I have a new Solar Spectrum Research Grade 0,4x Telecompressor 2" that I never used because I don't know what it does in the imaging train ...
Before my Solar Spectrum Ha filter I use a 5x Telecentric that I need to have a good F30+ value.
So my question, is the RG 0,4x Telecompressor redundant or can I use it with my 5x Telecentric and what is than te result on my image?
If I can't use it properly than I will sell it and move it to the "Solar Astronomy Shop and Swap".
Before my Solar Spectrum Ha filter I use a 5x Telecentric that I need to have a good F30+ value.
So my question, is the RG 0,4x Telecompressor redundant or can I use it with my 5x Telecentric and what is than te result on my image?
If I can't use it properly than I will sell it and move it to the "Solar Astronomy Shop and Swap".
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Re: Solar Spectrum RG 0,4x Telecompressor 2".
I think I would say try it Maurits and see if you ae happy with the results, if not, sell it.
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Re: Solar Spectrum RG 0,4x Telecompressor 2".
I think I have the 0.4x and the 0.7x telecompressor. I have tried to use both but I don't understand the maths about how to work out the length, all I know is that it shortens the distance at the back end. Also, when I use it, it shows that the TZ4 is so not straight that the round circle that the image is in is so far over to the left it doesn't include the on band region of the SolarSpectrum. The whole lot seems a bit useless to me but then I can't get the SolarSpectrum on band anyway. I have all the information of how to use the 0.4x and the measurements with a TZ3 at home and I am not at home right now so I am no help at all but I guess it doesn't help with a 5x either.
The telecompressor screws into the SS directly on the camera side, you will then have to shorten the distance drastically between SS and the camera chip. You will get vignetting but the image scale will be 0.4x smaller (better for bad seeing). Valery always tells me to increase the f number to at least f40-50, then use the telecompressor to bring you back to f25-30.
Alexandra
The telecompressor screws into the SS directly on the camera side, you will then have to shorten the distance drastically between SS and the camera chip. You will get vignetting but the image scale will be 0.4x smaller (better for bad seeing). Valery always tells me to increase the f number to at least f40-50, then use the telecompressor to bring you back to f25-30.
Alexandra
Re: Solar Spectrum RG 0,4x Telecompressor 2".
Hi Alexandra,
The 5X telecentric, I hope it was designed for you scope. If your using a 5X PowerMate with anything narrower than .6Angs you will see wavelength shift from the edges to the center. If you are using a TZ4 which has a back focus of 200-225mm( when you have it at the correct distance from prime focus) then I would think that the filter sitting about 100-150mm from the back of the telecentric would be a good distance. With the .4X telecompressor on the back side(red) . The focus to the camera should be 74mm. You should have some play with the focuser to reach the 74mm focus of the .4X telecompressor.\
Let us know how it works out for you.
Mark W.
The 5X telecentric, I hope it was designed for you scope. If your using a 5X PowerMate with anything narrower than .6Angs you will see wavelength shift from the edges to the center. If you are using a TZ4 which has a back focus of 200-225mm( when you have it at the correct distance from prime focus) then I would think that the filter sitting about 100-150mm from the back of the telecentric would be a good distance. With the .4X telecompressor on the back side(red) . The focus to the camera should be 74mm. You should have some play with the focuser to reach the 74mm focus of the .4X telecompressor.\
Let us know how it works out for you.
Mark W.
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Re: Solar Spectrum RG 0,4x Telecompressor 2".
Thanks Mark for these distances, this is very useful for me I need to try this as I only had the distances needed for the TZ3 + TC on the C11. The TZ4 and TC on the tec140 was a mystery. I do not have a 5x telecentric from Beloptik yet, I am still trying to fathom the TZ4. The TZ4 is so off centre it is useless. My main problem at the moment is that the etalon won't heat up whatever temperature I put it at. First I set it at 24 degrees and the heater stopped at 22.5 degrees. After unplugging several times it started heating up but all I got was a white light view. Sadly, I am not sure I will be able to do any more testing before February now. Usually it is something I have done by mistake
Alexandra
Alexandra
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Re: Solar Spectrum RG 0,4x Telecompressor 2".
My two below images on 06/10/22:mdwmark wrote: ↑Thu Oct 06, 2022 6:19 am Hi Alexandra,
The 5X telecentric, I hope it was designed for you scope. If your using a 5X PowerMate with anything narrower than .6Angs you will see wavelength shift from the edges to the center. If you are using a TZ4 which has a back focus of 200-225mm( when you have it at the correct distance from prime focus) then I would think that the filter sitting about 100-150mm from the back of the telecentric would be a good distance. With the .4X telecompressor on the back side(red) . The focus to the camera should be 74mm. You should have some play with the focuser to reach the 74mm focus of the .4X telecompressor.\
Let us know how it works out for you.
Mark W.
SolarSpectrum, RG 0.4x tele compressor than 2" adapter with inside Daystar 0.5x reducer and after that the camera.
The 74 mm distance was respected.
The images were sharp in the center, but not good uniform and bad on the edges...
In the above 4 images I used only the 0.5x Daystar reducer, not the RG tele compressor, the images were okay.
I think that I need to remove the Daystar 0.5x reducer instead of using both (tele compressor and reducer) and test with only the RG tele compressor.
I will try that as soon as possible and let the results know.
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Re: Solar Spectrum RG 0,4x Telecompressor 2".
I'm following this thread closely as I have place a deposit on a Solar Spectrum 0.3A Ha filter through Alpine Astronomical back back in July and I'm awaiting for it's arrival once it's built. I have the TZ3 and the 0.4x reducer for my iStar Optical 150mm f/10 scope which I'm currently building the OTA.
I'm a bit concerned that your field of view is offset Alexandra, I do know that the field of view decreases with the focal reducer but with a smaller camera chip that should not be a problem.
George
I'm a bit concerned that your field of view is offset Alexandra, I do know that the field of view decreases with the focal reducer but with a smaller camera chip that should not be a problem.
George
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Re: Solar Spectrum RG 0,4x Telecompressor 2".
I did a test with just the RG 0.4x Tele Compressor on the SolarSpectrum.
The result is not as good as I thought, namely quite a bit of vignetting to the corners of the shot.
Then I only used my Daystar 0.5x reducer again with very nice results.
In my setup I get on better with the Daystar 0.5x reducer and it is easier to get into focus.
The result is not as good as I thought, namely quite a bit of vignetting to the corners of the shot.
Then I only used my Daystar 0.5x reducer again with very nice results.
In my setup I get on better with the Daystar 0.5x reducer and it is easier to get into focus.
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Re: Solar Spectrum RG 0,4x Telecompressor 2".
Hi Maurits,
Which camera are you using? With the 0.4x Tele Compressor you will get 46mm x 0.4 = 18.4mm field of view without vignetting at the corners. With the Daystar 0.5x reducer assuming that it too has a clear aperture of 46mm then your unvignetted field of view should be 23mm.
George
Which camera are you using? With the 0.4x Tele Compressor you will get 46mm x 0.4 = 18.4mm field of view without vignetting at the corners. With the Daystar 0.5x reducer assuming that it too has a clear aperture of 46mm then your unvignetted field of view should be 23mm.
George
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Re: Solar Spectrum RG 0,4x Telecompressor 2".
George, I use the ASI174MM camera.GeorgeIonas wrote: ↑Sun Oct 09, 2022 6:45 pm Hi Maurits,
Which camera are you using? With the 0.4x Tele Compressor you will get 46mm x 0.4 = 18.4mm field of view without vignetting at the corners. With the Daystar 0.5x reducer assuming that it too has a clear aperture of 46mm then your unvignetted field of view should be 23mm.
George
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Re: Solar Spectrum RG 0,4x Telecompressor 2".
Maurits, the ASI174mm camera is about 13.3mm across the diagonal, so theoretically you should have no vignetting.
I wonder what Baader response is since they recommend the 0.4x Tele compressor for solar Ha use.
George
I wonder what Baader response is since they recommend the 0.4x Tele compressor for solar Ha use.
George
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Re: Solar Spectrum RG 0,4x Telecompressor 2".
George, if I had the chance I will test it again and measure the exact dimensions, I let it know.
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Re: Solar Spectrum RG 0,4x Telecompressor 2".
Is it not the free aperture of the etalon that is the key here, not the telecompressor?GeorgeIonas wrote: ↑Sun Oct 09, 2022 6:45 pm Hi Maurits,
Which camera are you using? With the 0.4x Tele Compressor you will get 46mm x 0.4 = 18.4mm field of view without vignetting at the corners. With the Daystar 0.5x reducer assuming that it too has a clear aperture of 46mm then your unvignetted field of view should be 23mm.
George
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Re: Solar Spectrum RG 0,4x Telecompressor 2".
I have today the SolarSpectrum prepared for the RG 0.4x tele compressor, according to Baader's instructions for optimal working (see picture).
As soon as possible I will to test but today it's cloudy with some rain.
As soon as possible I will to test but today it's cloudy with some rain.
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Re: Solar Spectrum RG 0,4x Telecompressor 2".
I get terrible vignetting with the ASI174 with the TC, so I am very interested to hear about the Daystar 0.5x
Alexandra
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Re: Solar Spectrum RG 0,4x Telecompressor 2".
I have very good results with the Daystar 0.5x reducer and the SS, uniform, no vignetting in the field.
If I need the Daystar 20 mm corresponding extension then I have a 0.33x reduction.
The images on SolarChat 09/10/22 Region... I used here the Daystar 0.5x reducer.
Here are pictures from my setup:
First one: Daystar without 20 mm extension
Second one: Daystar with 20 mm extension.
Last edited by MAURITS on Tue Oct 11, 2022 11:24 am, edited 2 times in total.
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Re: Solar Spectrum RG 0,4x Telecompressor 2".
This morning I was able to test the RG 0.4x TC with the correct settings according to Baader.
The result is very sad, can't get focus, lots of vignetting, unwanted light scatter, blurry light blob ... I think worthless in use with my SolarSpectrum filter and ASI174MM camera.
That stated what Alexandra ment.
For my setup it's lost of money.
Than I switch back to the "Daystar 0.5x reducer setup" and I saw a beautiful view of the autumn sun.
I am satisfied that I have taken this test seriously.
Thanks again for the feedback and comments.
The result is very sad, can't get focus, lots of vignetting, unwanted light scatter, blurry light blob ... I think worthless in use with my SolarSpectrum filter and ASI174MM camera.
That stated what Alexandra ment.
For my setup it's lost of money.
Than I switch back to the "Daystar 0.5x reducer setup" and I saw a beautiful view of the autumn sun.
I am satisfied that I have taken this test seriously.
Thanks again for the feedback and comments.
Last edited by MAURITS on Sat Jan 28, 2023 8:58 am, edited 1 time in total.
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Re: Solar Spectrum RG 0,4x Telecompressor 2".
I also have the Daystar reducer, but rarely use it. If the seeing doesnt support the aperture on a day then its kind of not really satisfying to get results of a way smaller aperture. I think the reducer idea is mostly meant to be for visual use, so that you would get a contrasty and stable image with a low power eyepiece. For this the etalon has to have a certain diameter, the larger the better.
Another application is on cameras with very small chips unlike the asi 174.
Another application is on cameras with very small chips unlike the asi 174.
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Re: Solar Spectrum RG 0,4x Telecompressor 2".
Finally Finally Finally ...
It was hard for me to believe that a relatively expensive filter would not be useful...
After a long search and a lot of think it, I found the solution for a PERFECT working filter with the SolarSpectrum Ha filter.
The distance from the side 0.4x tele-compressor is NOT 74mm BUT 43mm.
The result is a very clear image because I now get everything in focus very well.
Between the camera and the tele-compressor I have a tilter to remove the NR's.
This makes me happy because I now know that the tele-compressor is finally not wasted money, but a very efficient part in the imaging train.
In Solarchat forum under 19/10/22 are some solar pictures taken with this combination.
It was hard for me to believe that a relatively expensive filter would not be useful...
After a long search and a lot of think it, I found the solution for a PERFECT working filter with the SolarSpectrum Ha filter.
The distance from the side 0.4x tele-compressor is NOT 74mm BUT 43mm.
The result is a very clear image because I now get everything in focus very well.
Between the camera and the tele-compressor I have a tilter to remove the NR's.
This makes me happy because I now know that the tele-compressor is finally not wasted money, but a very efficient part in the imaging train.
In Solarchat forum under 19/10/22 are some solar pictures taken with this combination.
Last edited by MAURITS on Wed Oct 19, 2022 4:59 pm, edited 1 time in total.
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Re: Solar Spectrum RG 0,4x Telecompressor 2".
That's interesting!
Is the 43mm from the SolarSpectrum to the camera chip, or from the 0.4xTC to the camera chip?
Alexandra
Is the 43mm from the SolarSpectrum to the camera chip, or from the 0.4xTC to the camera chip?
Alexandra
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Re: Solar Spectrum RG 0,4x Telecompressor 2".
The 43 mm is from the 0.4x side to the camera chip, when you look above to the dimension image than you swith the 74 mm to the 43 mm.
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Re: Solar Spectrum RG 0,4x Telecompressor 2".
I measured the focal length of the 0.4x Tele-compressor to be about 150mm so calculating its reduction was easy. I used 45mm distance from the tele-compressor to chip and found that the compression factor was 0.7x.
I did a few more calculations below to get the relevant reductions.
150mm-45mm/150mm=0.7x reduction and 0.7x46mm(tele-compressor lens diameter)=32.2mm FOV
150mm-75mm/150mm=0.5x reduction and 0.5x46mm=23mm FOV
150mm-90mm/150mm=0.4x reduction and 0.4x46mm=18.4mm FOV
So I get different results from Maurits and Solar Spectrum, maybe the Telecentric Barlow contributes to this discrepancy?
It would be interesting if Maurits take two images, one native and the other with the tele-compressor to confirm the reduction value.
George
I did a few more calculations below to get the relevant reductions.
150mm-45mm/150mm=0.7x reduction and 0.7x46mm(tele-compressor lens diameter)=32.2mm FOV
150mm-75mm/150mm=0.5x reduction and 0.5x46mm=23mm FOV
150mm-90mm/150mm=0.4x reduction and 0.4x46mm=18.4mm FOV
So I get different results from Maurits and Solar Spectrum, maybe the Telecentric Barlow contributes to this discrepancy?
It would be interesting if Maurits take two images, one native and the other with the tele-compressor to confirm the reduction value.
George
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Re: Solar Spectrum RG 0,4x Telecompressor 2".
George,GeorgeIonas wrote: ↑Thu Oct 20, 2022 4:04 am
It would be interesting if Maurits take two images, one native and the other with the tele-compressor to confirm the reduction value.
George
I have for the moment only one image with te tele- compressor from yesterday.
We have now lots of rain for a few days, but when I have the chance I take one native and one image with that reducer.
So the images from yesterday with the tele- compressor.
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Re: Solar Spectrum RG 0,4x Telecompressor 2".
That sound great Maurits. It would be interesting to see if 43mm does provide a 0.4x reduction in the focal length. Your images look very good with the tele-compressor.
George
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Re: Solar Spectrum RG 0,4x Telecompressor 2".
I have done a little fine tuning, so I removed the previous adaper between the SolarSpectrum and the tele-compressor.
The tele-compressor is now straight away on the 2" SolarSpectrum, (maybe 1 or 2 mm toward the SS).
After the T-C I have the Baader adapter 2"/T2a (#2958244) to connect with the tilter or other T2 equipment.
I did that because Arne noted that the left side on the image was less sharp, and I think the direct connection to the SolarSpectrum will give some improvement, at least I hope ...
The tele-compressor is now straight away on the 2" SolarSpectrum, (maybe 1 or 2 mm toward the SS).
After the T-C I have the Baader adapter 2"/T2a (#2958244) to connect with the tilter or other T2 equipment.
I did that because Arne noted that the left side on the image was less sharp, and I think the direct connection to the SolarSpectrum will give some improvement, at least I hope ...
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Re: Solar Spectrum RG 0,4x Telecompressor 2".
I did a last change in the 0.4x TeleCompressor setup.
I use a 2" adapter on the SS filter with inside the 2" 0.4x TeleCompressor.
The advantage is that I can quick change the TeleCompressor and use a 2" noisepiece instead, depends on the seeing.
After the TeleCompressor I have the Interference Eliminator and the ASI 174MM camera.
The whole combination works just PERFECT, with no signs of vignetting.
I use a 2" adapter on the SS filter with inside the 2" 0.4x TeleCompressor.
The advantage is that I can quick change the TeleCompressor and use a 2" noisepiece instead, depends on the seeing.
After the TeleCompressor I have the Interference Eliminator and the ASI 174MM camera.
The whole combination works just PERFECT, with no signs of vignetting.
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Re: Solar Spectrum RG 0,4x Telecompressor 2".
In your case it makes really sense to use the 0.4 telecompressor that you have. Since you need high f-ratios with the 0.3A filter (f/50?).GeorgeIonas wrote: ↑Sun Oct 09, 2022 2:46 am I'm following this thread closely as I have place a deposit on a Solar Spectrum 0.3A Ha filter through Alpine Astronomical back back in July and I'm awaiting for it's arrival once it's built. I have the TZ3 and the 0.4x reducer for my iStar Optical 150mm f/10 scope which I'm currently building the OTA.
I'm a bit concerned that your field of view is offset Alexandra, I do know that the field of view decreases with the focal reducer but with a smaller camera chip that should not be a problem.
George
The field of view offset of Alexandra sounds like a out of collimation telecentric.
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Re: Solar Spectrum RG 0,4x Telecompressor 2".
Note,
Off the record, but with the SS double stack 0.7A/0.65A I have now a SS ~ 0.48 Angs.
Off the record, but with the SS double stack 0.7A/0.65A I have now a SS ~ 0.48 Angs.
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Re: Solar Spectrum RG 0,4x Telecompressor 2".
This has been a great thread.
My first take away is that Baader’s listed working distance of the .4 X tele-compressor might not be correct.
That perhaps 43mm works better than the stated 74mm. It sounds like it remains to be seen whether this gives .4 X .
I am confused as to how the .4 X tele-compressor affects the original specified distance (220mm) from the back of the 4X telecentric to the camera chip.
My first take away is that Baader’s listed working distance of the .4 X tele-compressor might not be correct.
That perhaps 43mm works better than the stated 74mm. It sounds like it remains to be seen whether this gives .4 X .
I am confused as to how the .4 X tele-compressor affects the original specified distance (220mm) from the back of the 4X telecentric to the camera chip.
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Re: Solar Spectrum RG 0,4x Telecompressor 2".
I’m also confused as to which side of the .4 X goes to the telescope, and which to the sensor? One side is strongly concave, the other is mildly convex. I don’t trust it being referenced by the lettering on the label, as my 4x telecentric label was backwards.
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Re: Solar Spectrum RG 0,4x Telecompressor 2".
David, I think the short side faces the telescope end and the long side goes toward the camera.
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Re: Solar Spectrum RG 0,4x Telecompressor 2".
Thanks. Y’all are the best.
As to the change in spacing between the sensor and the telecentric, I am wondering if this distance is shortened when using the telecompressor
As to the change in spacing between the sensor and the telecentric, I am wondering if this distance is shortened when using the telecompressor