AR 2822 May 12 2021

[Solsearcher]

My sky was clear but it was a bit windy . First one was my 90mm double stack with 1.6x and the second image is with my 150mm Istar mod . Both shot with vintage DMK 31 camera and processed using out dated methods lol . 50 frames stacked in registax out of 1000 and a quick run through PS Elements

[Lady Fraktor]

Very nice Sol, Sol

[Graeme1858]

That's a very fine AR 2822 Sol.

Regards

Graeme

[Thefatkitty]

Nicely done Mike; nice detail and the colour version is great!

All the best,

[messier 111]

wow nice capture , thx .

[FRAZ]

Hi Mike,

You have a fantastic image there (evidenced by appearance in smaller format) and are suffering due to limited good frames due to your conditions I think. I've been there, you cant get an APOD every day

How does this look with more images stacked for SNR? I get bad SNR with bad seeing unless I go for 3 or 4000 frames and stack 10% of them. On days of good seeing i can stack 25% but that is rare and need great seeing. I would be interested in your findings on this score.

Related to outdated methods, the biggest gain I got on restart was using IMPPG for Lucy and would recommend trying it. I used to go all smart sharpen in photoshop but IMPPG is pretty instant too. I never really got it right with registax although others love it.

I feel a bit like teaching grandma to suck eggs but we always were straight with each other and I hope that still counts for something.

Best
Fraz.

[Ylem]

Very nice Mike
Lots of details.

[Solsearcher]

Hi Mike,

You have a fantastic image there (evidenced by appearance in smaller format) and are suffering due to limited good frames due to your conditions I think. I've been there, you cant get an APOD every day

How does this look with more images stacked for SNR? I get bad SNR with bad seeing unless I go for 3 or 4000 frames and stack 10% of them. On days of good seeing i can stack 25% but that is rare and need great seeing. I would be interested in your findings on this score.

Hi Fraz , Thank you for your comments
First you are looking at 2 different images shot with very different scopes , the first or smaller format as you referred was shot with my 90 x 900mm double stack at 1.6X and the last image was shot with my 150x 1500mm single stack at native F/L . My smaller 900mm scope was more forgiving in the wind so I had better frames to stack from this scope and that is why the first image looks better . My 150 is a monster and was not at all forgiving of the wind so one issue with the second image was more the scope not being steady than the sky conditions .
What you are saying about capturing more frames on poor condition days makes sense if you are lucky enough to catch enough steady sky to grab enough frames to make an image , the odds are more in your favor if you have more frames to work with . This is a good tip but for myself I will rarely struggle with poor conditions anymore , now I will not set up unless I know my sky will support good captures . When my video is good I will usually go the other way and reduce my stack to 50 to get rid of any iffy frames that can hinder the stack .
My referral to out dated processing methods is accurate , I have not kept up with the ever evolving programs or methods . My approach has been to concentrate the majority of my effort into the capture , if my video has lots of crisp and clear frames it will take little processing to make a decent image . I also lean towards the less sharpened and softer look when I process my images .
I certainly don't post images expecting to win an AOPD , there are many amazing images posted here every day and besides solar is easy compared to the data gathering and processing that the deep sky guys and gals do . It has always been a pleasant and unexpected surprise to have my images selected .

[FRAZ]

An interesting approach to stack less frames I must admit but you will get butchered by noise. Having said that I remember one post elsewhere in which an imager specifically chose a few select shots on a prominence and stacked only 3 images so that might be worth investigating further. He too chose specific times and targets only.

From personal experience I always get grain in my images the less I stack. I guess you know your process better than I do.

[Solsearcher]

Hi Fraz
As you know I have been doing this for a while now , my processing is very basic and I have become complacent in my routine . I will only set up when my sky conditions are good or better and will shoot 1000 frames , out of these I want a minimum of 50 to stack . I could be wrong but believe that 50 is enough if the frames are very good . My reasoning is if I increase the stack size it will start including some of the not so good frames and I find that can hinder the stack and end result . I try to keep my stack to around 50 but no less to try to eliminate the "close but no cigar" frames .
I am still capturing with my old DMK's and running everything through my Win 7 laptop , just like me my equipment is getting out dated lol !
Best regards
Mike

[TheButcher]

Excellent Capture Sol!

[FRAZ]

Hi Mike,

I found a really interesting thread on this subject that supports your numbers very strongly, particularly at high scale.

https://www.cloudynights.com/topic/6100 ... ominences/

[Solsearcher]

That is a good post Fraz , I am sure that I had seen something similar to lead me in that direction , we learn our methods from what is shared . I believe the number of "stackable" frames you can use will be highly dependent on the quality of the video and the video quality will depend on sky conditions . My 50 frame average relates to the quality of the video I am able to capture in my average conditions . When we watch our videos we look for that best frame to use as the "master" . As I watch my videos I see lots of distorted frames but also some clear and stable frames blended through out . The video I am able to capture in my average conditions would never have 25% clear non distorted frames , it would be closer to 5 or maybe 10% on a very good day . My approach has been to try to only use only the best frames in the video for the stack , by keeping the stack size down I am directing the stacking program to be more critical of it's frame selections .
There are no set numbers for this , if I lived in Hawaii I would likely have no trouble fattening up my stack size !!
Good post Fraz nice to see the direct comparisons .

[FRAZ]

One last minor point to support the stacking of a number of subs that I took from night time images.

If you want to halve the noise in an image you will stack 4 subs, to halve this again you stack 16 and halve again would be 64 then 256 and so on. This is why I try to take video of 2560 frames and stack 10%. For medium format shots of surface detail this should still be a consideration for a good noise control parameter. (Prominence data will always suffer more from noise control issues and needs a subtle hand due to the software registiring data as noise in some cases, particularly as prominences tend to be faster moving).

There are many parameters (as you indicate) that all play together, such as seeing and sharpening for example. Most denoise routines especially the one in registax if tweaked incessantly can help with noise too if you have the patience.

[FRAZ]

So this is the smoothest image I have shot for a while. I took it a few weeks ago but it is a good example of what we are talking about. If viewed at maximum size it is really smooth. Shot at 4000 frames I looked at the quality of the frames as it was stacked and chose to stack 25% because seeing was good in the image and in the quality in AS3. I just moved the slider down after analysis to guage a good level. This isn't always straight forward like it was on this clear occasion.

1000 frames doesn't fit into my nice snr quantities but it will pick out the best frames anyway and becomes another bonus parameter in the overall equation. There are many ways to build the perfect picture, we just need to make incremental changes that give us the best opportunity.

[Solsearcher]

I hear everything you are saying Fraz and intend to at least double my usual frame count next time I set up so I can have something to work with .
I still had the video from the first image so increased the stack to 65 and tightened things up a bit . I only had 1000 frames and the wind was against me so I couldn't get too greedy with my stack or the detail would suffer , this is the result .

[Makuser]

Hi Mike. A superb solar AR 2822 image. Nice granularity and the plages are quite visible. I like both the b&W and color versions. Thanks for sharing these with us Mike, and keep up the great work.