Which etalon is better? Please, look, think and vote.

this is the main message area for anything solar :)
Post Reply
User avatar
Valery
Way More Fun to Share It!!
Way More Fun to Share It!!
Posts: 4059
Joined: Sun Nov 18, 2012 3:13 pm
Has thanked: 156 times
Been thanked: 893 times

Which etalon is better? Please, look, think and vote.

Post by Valery »

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
Attachments
1 vs 2.png
1 vs 2.png (1.11 MiB) Viewed 2474 times
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.
User avatar
Montana
Librarian
Librarian
Posts: 34563
Joined: Mon Oct 17, 2011 5:25 pm
Location: Cheshire, UK
Has thanked: 17672 times
Been thanked: 8791 times

Re: Which etalon is better? Please, see, think and vote.

Post by Montana »

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


User avatar
Martin_S
Way More Fun to Share It!!
Way More Fun to Share It!!
Posts: 1839
Joined: Sat Mar 16, 2019 12:34 am
Location: Brisbane , Australia
Has thanked: 979 times
Been thanked: 2992 times

Re: Which etalon is better? Please, see, think and vote.

Post by Martin_S »

I agree with Alexandra, number 2 shows better contrast and more detail.

Martin


H alpha : ,Skywatcher 120mm F8 open frame refractor, a tilted 2" 7nm H-alpha filter as a sub energy rejection filter, Baader TZ4 telecentric focal extender, Player One energy rejection filter, Combo Quark Chromosphere, Naked PST etalon for double stacking, ASI74mm camera
User avatar
MalVeauX
Way More Fun to Share It!!
Way More Fun to Share It!!
Posts: 1858
Joined: Tue May 09, 2017 7:58 pm
Location: Florida
Has thanked: 1171 times
Been thanked: 1360 times

Re: Which etalon is better? Please, look, think and vote.

Post by MalVeauX »

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,


User avatar
eroel
Way More Fun to Share It!!
Way More Fun to Share It!!
Posts: 9408
Joined: Mon Dec 19, 2011 10:45 pm
Location: México D.F.
Been thanked: 4904 times

Re: Which etalon is better? Please, look, think and vote.

Post by eroel »

Valery:
I like better the first one. (F/30)
I agree with Marty.
Best regards,
Eric.


User avatar
MAURITS
Way More Fun to Share It!!
Way More Fun to Share It!!
Posts: 8507
Joined: Tue Nov 27, 2018 4:37 pm
Location: Belgium
Has thanked: 2412 times
Been thanked: 4787 times
Contact:

Re: Which etalon is better? Please, look, think and vote.

Post by MAURITS »

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.


Regards,
Maurits

Vista del Cielo Observatory

www.vistadelcielo.be
Sungazer
Ohhhhhh My!
Ohhhhhh My!
Posts: 58
Joined: Wed Apr 02, 2014 1:59 pm
Location: N.Hants
Been thanked: 3 times

Re: Which etalon is better? Please, look, think and vote.

Post by Sungazer »

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. :bow


User avatar
pedro
Way More Fun to Share It!!
Way More Fun to Share It!!
Posts: 12256
Joined: Sun May 01, 2016 8:26 pm
Location: Portugal
Has thanked: 14 times
Been thanked: 6577 times
Contact:

Re: Which etalon is better? Please, look, think and vote.

Post by pedro »

I also prefer the first (left) image, better contrast and more detail can be seen


User avatar
marktownley
Librarian
Librarian
Posts: 42274
Joined: Tue Oct 18, 2011 5:27 pm
Location: Brierley Hills, UK
Has thanked: 20442 times
Been thanked: 10246 times
Contact:

Re: Which etalon is better? Please, look, think and vote.

Post by marktownley »

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.


Image
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!
bart1805
Almost There...
Almost There...
Posts: 636
Joined: Mon Feb 06, 2017 9:04 pm
Location: The Netherlands
Been thanked: 1 time

Re: Which etalon is better? Please, look, think and vote.

Post by bart1805 »

I agree with Mark. Both excellent.


User avatar
Valery
Way More Fun to Share It!!
Way More Fun to Share It!!
Posts: 4059
Joined: Sun Nov 18, 2012 3:13 pm
Has thanked: 156 times
Been thanked: 893 times

Re: Which etalon is better? Please, look, think and vote.

Post by Valery »

Thanks to all who expressed his opinion.

Valery


"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.
User avatar
marktownley
Librarian
Librarian
Posts: 42274
Joined: Tue Oct 18, 2011 5:27 pm
Location: Brierley Hills, UK
Has thanked: 20442 times
Been thanked: 10246 times
Contact:

Re: Which etalon is better? Please, look, think and vote.

Post by marktownley »

How do you rate the etalons Valery?


Image
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!
User avatar
Valery
Way More Fun to Share It!!
Way More Fun to Share It!!
Posts: 4059
Joined: Sun Nov 18, 2012 3:13 pm
Has thanked: 156 times
Been thanked: 893 times

Re: Which etalon is better? Please, look, think and vote.

Post by Valery »

marktownley wrote: Tue Nov 05, 2019 6:53 pm How do you rate the etalons Valery?
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.
Post Reply