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Sol Ha 22 Nov - powermate or no power mate?


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The sun has been lovely the last few days & I have managed to get some data that I will process & post.

On one of the mornings, I had enough time to try w and w/o a 2.5x PM.  Which ones are better?

The kit is TV76 w SF50 (ie effectively f9.6) w ASI290MM (2.9um pixel size).  So w/o PM that's a ratio of about 3.3.  With the PM that rises to 8.3.  I think the ideal ratio is mean to be about 4-5x right?  So would it be better to not use a PM and just use ROI?

I think the w/o PM images are better (& file sizes a lot smaller for some strange reason)?



No PM:1520135116_Sun_114424_l3_P25_ap223_imppg(211123)_nopm_gimp.png.bdcf530f7ccf176986b30f5e550aba74.png




No PM: 



PM: Sun_120334_l4_P5_ap1763_imppg(211122t2)_gimp.thumb.png.aa1b88cf72cd44730690f82b69fc108e.png

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Thanks @Highburymark - yes v happy w the SF50.  I actually dread to think what a DS version would show.

You're right about the last image being soft - if I remember correctly, I was wary of doing too much in ImPPG.  I think I still have the original footage so I may see if something more can be done with it, or if that's just the original footage limiting it.

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  • 2 weeks later...

Very nice. I don't know about ratios but I prefer the powermate shots. I used to prefer keeping image sizes smaller and sharper before, but since moving to a larger monitor, I think I prefer the larger images, even if they aren't as sharp.

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  • 1 month later...

Image No2 is by far the best IMO.
Both smaller images show over-sharpening. IMO.
The "surface texture" is unrealistically uniform. IMO.
It is an easy mistake to make and I used to do it a lot.
You keep pushing because it looks more "exciting."

The step up in scale between the pairs of images is too much. IMO.
Here I am judging your images as harshly as I would my own.
Flattery will not bring you the progress you desire.

I made the same mistakes when I first imaged in H-a.
Somebody on a forum told me I was overcooking the sharpening. It hurt!
So I learned to be far more subtle in ImPPG. To aim only for realism.

I use inexpensive T-S binoviewer GPCs [singly] as Barlows on the nose of my ASI174.
Now I match the GPC/Barlow power to the seeing conditions.
They act as much weaker Barlows on the camera nose than they would on a binoviewer.
Simply because they are much closer to focus.
I have only extremely rarely been able to use a 2x Shorty Barlow.

In ImPPG I use 1.3 [default] L-R Deconvolution. With 2.6 Sigma and 1.3 Amount when I can.
It is extremely rare that I can go any higher. In winter, with a low sun, I sometimes reduce L-R-C to only 1.
These settings are only intended as guide. A starting point based on my own system. 150/10 PST mod.

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Thanks @Rusted this is exactly the type of constructive feedback that I welcome & that is so helpful.  Yes you're right about the sharpening "journey" - when I look back at my earliest images, I sometimes wince - but that's how one learns :)

I've noticed w my lunar images as well that less is definitely more - I need to continue that on the solar side.  Luckily am sitting on lots of data from the last week or so that I have not yet looked at 😂

That's pretty neat on fitting the GPC into the camera nose itself.  I have yet to get my head around when to (or when not to) try upping the scale based on seeing & my chip sizes.  Something to work on over 2022 hopefully!

Thanks again - hope the skies have been as kind to you as they have been here lately!

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I'm glad you saw my comments as constructive. :thumbsup:
When ImPPG was recommended I was completely lost.
No idea where to start. Horrendous results! Tears of anguish!  :icon_rolleyes:

ImPPG works well even with default settings. Just drag the wiggly line in the box.
I usually keep the first cursor on the bottom line. "Brightness" cursor on the top line.
Less is indeed more. I process "live" while I capture using a 27" monitor in the shade of the dome.

They say that practice makes perfect. I badly needed the practice to gain enough experience.
So I capture and process continuously. Usually at less than half minute intervals.
Often from early morning to sunset if the sun is out and the seeing is worthwhile.
SharpCap, AS!3, ImPPG, PhotoFiltre. Then post the better results on my blog.
Or on the solar forums if they aren't too awful. :blush:

Most solar imagers don't get as many active hours in a month as I do in a day.
It was really the only way I was ever going to progress to any degree of proficiency at my age.

The GPCs on the nose I owe to Sir Peter Drew.
Some Barlow nose-pieces can be used the same way. Screw thread permitting.
Skywatcher Barlow noses work according to Peter. I never had one to play with.

I mostly use a 2x WO Barlow nose piece. Or a 1.6x TS GPC if the seeing is poor. 2.6x only if the seeing is great.
150mm f/10 iStar H-a refractor. With a 1.25x Baader GPC permanently on the back of the PST etalon.

Peter is also responsible for sending me down the H-alpha [PST modification] rabbit hole. :icon_scratch:

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