Which etalon is better? Please, look, think and vote.
- Valery
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Which etalon is better? Please, look, think and vote.
Hi all,
I need your little but important help, friends.
Here are two images which were taken not too far apart (in time) from the same location but through two different telescopes and different etalons.
Left image was taken with F/30 (on the etalon) and right image was taken with F/42 (on the etalon).
So, the question: which etalon you rate more narrow and more uniform?
Thanks for reading and your votes.
Valery
I need your little but important help, friends.
Here are two images which were taken not too far apart (in time) from the same location but through two different telescopes and different etalons.
Left image was taken with F/30 (on the etalon) and right image was taken with F/42 (on the etalon).
So, the question: which etalon you rate more narrow and more uniform?
Thanks for reading and your votes.
Valery
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Last edited by Valery on Thu Oct 31, 2019 11:33 am, edited 1 time in total.
"Solar H alpha activity is the most dynamic and compelling thing you can see in a telescope, so spend accordingly." (c) Bob Yoesle.
Largest full size 185 - 356mm Dielectric Energy Rejection Filters (D-ERF) by ARIES Instruments.
Largest full size 185 - 356mm Dielectric Energy Rejection Filters (D-ERF) by ARIES Instruments.
- Montana
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Re: Which etalon is better? Please, see, think and vote.
Absolutely marginal Valery but I reckon number 2 is slightly better. It is overall marginally more 3D (less flat) and the key for me is the plage to the right of the filament, it is very slightly brighter and more fluffy on the right indicating a tighter bandpass. It is marginal, both are fabulous.
Alexandra
Alexandra
- Martin_S
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Re: Which etalon is better? Please, see, think and vote.
I agree with Alexandra, number 2 shows better contrast and more detail.
Martin
Martin
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- MalVeauX
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Re: Which etalon is better? Please, look, think and vote.
Hi Valery,
Would you kindly check out my PM to you on here?
I think the etalon on the left is probably better. My reasons: It's nearly the same as the one on the right, at F42, yet it's doing it at F30. So if they were both brought to F42, the one on the left would be superior and more narrow. I'm specifically looking at the contrast on the fibrils, they're darker, slightly, on the right side image, to me being a little more selective and narrow band, just like filaments will be darker in that sense. Yet the F30 image is doing nearly the same thing, just nearly, at only F30. So if it were brought up to F42, it would likely be better. Uniformity seems to be essentially equal, everything looks onband in the same locations. There's a little super granulation peaking through on both maybe, to be expected with a single etalon like this.
Very best,
Would you kindly check out my PM to you on here?
I think the etalon on the left is probably better. My reasons: It's nearly the same as the one on the right, at F42, yet it's doing it at F30. So if they were both brought to F42, the one on the left would be superior and more narrow. I'm specifically looking at the contrast on the fibrils, they're darker, slightly, on the right side image, to me being a little more selective and narrow band, just like filaments will be darker in that sense. Yet the F30 image is doing nearly the same thing, just nearly, at only F30. So if it were brought up to F42, it would likely be better. Uniformity seems to be essentially equal, everything looks onband in the same locations. There's a little super granulation peaking through on both maybe, to be expected with a single etalon like this.
Very best,
- eroel
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Re: Which etalon is better? Please, look, think and vote.
Valery:
I like better the first one. (F/30)
I agree with Marty.
Best regards,
Eric.
I like better the first one. (F/30)
I agree with Marty.
Best regards,
Eric.
- MAURITS
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Re: Which etalon is better? Please, look, think and vote.
Valery, I like the first,
It is indeed marginal between the two images, but in the first image I see some finer details in the middle field.
It is indeed marginal between the two images, but in the first image I see some finer details in the middle field.
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- Ohhhhhh My!
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Re: Which etalon is better? Please, look, think and vote.
Hi Valery, After looking carefully,in my opinion the first one is more appealing,and has very slightly better definition. Though there is not a lot to of difference, probably a personal choice. I just wish my scope would be that good !!!! John.
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Re: Which etalon is better? Please, look, think and vote.
I also prefer the first (left) image, better contrast and more detail can be seen
Pedro Re'
https://pedroreastrophotography.com/
https://pedroreastrophotography.com/
- marktownley
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Re: Which etalon is better? Please, look, think and vote.
Both look essentially identical to me Valery, there are small differences, but is not night or day. If one can do it at f30 then to me that is better than f42, just on the grounds of shorter exposure and better sampling.
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- Valery
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Re: Which etalon is better? Please, look, think and vote.
Thanks to all who expressed his opinion.
Valery
Valery
"Solar H alpha activity is the most dynamic and compelling thing you can see in a telescope, so spend accordingly." (c) Bob Yoesle.
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- marktownley
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Re: Which etalon is better? Please, look, think and vote.
How do you rate the etalons Valery?
http://brierleyhillsolar.blogspot.co.uk/
Solar images, a collection of all the most up to date live solar data on the web, imaging & processing tutorials - please take a look!
- Valery
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Re: Which etalon is better? Please, look, think and vote.
My conservative estimation is that they are better than some expensive and larger 0,3A etalons.
"Solar H alpha activity is the most dynamic and compelling thing you can see in a telescope, so spend accordingly." (c) Bob Yoesle.
Largest full size 185 - 356mm Dielectric Energy Rejection Filters (D-ERF) by ARIES Instruments.
Largest full size 185 - 356mm Dielectric Energy Rejection Filters (D-ERF) by ARIES Instruments.