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First light on Saturn ... Drum Roll


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Hello

Please find my first attempt at Saturn. Advice needed on how I can improve capture and processing.

My adventure started at 6:00 am this morning taking on -2C ice and frost, to capture Saturn in the South before sunrise.

The transparency was good though and the stars looked really crisp against the still dark sky. (Exciting!)

I managed to capture two run of 39000 images at 65FPS at 15ms exposures, raw mono data.

Using my 127mm Mak (1500) with a 2x Barlow to get it up to 3000mm

Anyhow just finished processing, process followed was. (Was done in a bit of a rush.)

Dark Frame

10000 stack at -2C

Reference Frame

AS!2 - 25% using 4 quality setting, sharpening and mix in raw 50%, 

REGISTAX -  Wavelets and gamma adjusted, Histogram stretched.

Main Frame

AS!2 - 50% using 4 quality setting, sharpening and mix in raw 50%

REGISTAX -  Wavelets and gamma adjusted, Histogram stretched and increase size to 1.5

gallery_32740_2937_3132.jpg

I have been a bit aggressive with my wavelets and placed this on a black background, with a bit of mid-tone adjustment.

It feels a bit blurry and very yellow, not much in the blue channel, is this normal?

Do I need I need to up my FL to from 3000 to 4500? 

Lack detail for +-20000 images, should I up the exposure and reduce the images?

I am being overly critical for my equipment?

Thanks for the feedback, appreciate it guys.

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Thats a remarkable image Chris. For a 5" scope with Saturn so low and months off opposition.  I would stick with that fl maybe even reduce it slighlty. If you use auto rgb align and rgb balance in registax that will correct the colour issues.

Interesting you using dark frames which is not something one would normally do with planetary imaging.

This proves again how good the cmos cams are on Saturn.

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Thats a remarkable image Chris. For a 5" scope with Saturn so low and months off opposition.  I would stick with that fl maybe even reduce it slighlty. If you use auto rgb align and rgb balance in registax that will correct the colour issues.

Interesting you using dark frames which is not something one would normally do with planetary imaging.

This proves again how good the cmos cams are on Saturn.

Thanks for the words of encouragement.

Having been playing with the raw data and there is very little data in the blue channel.

Done some research and it could be due to Saturn lying low against the horizon, thus the atmosphere is acting likea orange filter and blocking the blue light. This happens when you get a blood moon.

I am going to try to create L channel to overlay and see if I can tease out more detail.

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This is the same stack of images, but with extract of the luminance with registax and the a blue filter applied in photo shop.

I had to up the exposure as the blue filter and luminance actually darked the image.

Not sure I am going to be able to do much better than this without more data / bigger scope. :) (getting ideas)

gallery_32740_2937_13136.jpg

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Nice to see Saturn returning this year, and this is a really early start at very low elevation.    Very nice capture indeed Chris and plenty of room for improvement as it nears opposition in May - let's hope for some good conditions.

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You did well with small scope and so low. Notice the ring angle this year guys Its opened a lot

Thanks Neil, it was really low, although because it is a bright object and day it only getting light so late I managed to gather data till just before 7am.

As we approach spring, I think it is going to become harder as it will be getting lighter with Saturn still lower.

I am tempted to get a bigger scope, but I have just got a 80ED for x-mas so will be doing some DSO work in the spring.

I think that's a damn fine effort given Saturn's distance and low elevation.

James

Thanks James, means a lot coming from you, I know you like to squeeze your equipment to get the most out of it.

Nice to see Saturn returning this year, and this is a really early start at very low elevation.    Very nice capture indeed Chris and plenty of room for improvement as it nears opposition in May - let's hope for some good conditions.

Thanks Jake, it is really low in elevation and has dramatically reduced my blue channel, although this is my first attempt at Saturn, so don't no what to expect.

I will post my stacked imaged data onto drop box for people to play with, may be I am trying to process it same as Jupiter and therefore missing a trick.

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Please feel free to download any of the streams and to play with them. Please provide feedback if you find that I missed something in the data.

(I can upload the raw data on request which is 3GB.)

39420 Raw images taken at 65FPS and 16ms exposure @ -2C with a 10000 Raw stacked dark frame

AS!2 Stacked Data:

Pre Normalise and Sharpen - Pure stack (0.4 mb)

25% with 4 Noise robust selection, pre-normalise & sharpen

50% with 4 Noise robust selection, pre-normalise & sharpen

50% with 4 Noise robust selection, post-normalise & sharpen

75% with 6 Noise robust selection, Post-normalise & sharpen

3x Drizzle Stack 75% with 6 Noise robust selection, Post-normalise / sharpen (4Mb)

If you get the drizzle data to work, please let me know what you did as it stumps me every time... muchas gracias

Have fun :)

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Just did a 3x drizzle image ... have to use very high wavelets did the auto balance and get a very blue image.

gallery_32740_2937_10608.jpg

Used Gamma setting to reduce the blue, but still have some blue fringes ... I will investigate colour noise reduction in image analyser.

Thanks for the tips so far all helps in the quest.

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You did well with small scope and so low. Notice the ring angle this year guys Its opened a lot

Hopefully get some more fine detail on the rings and even better North polar projection for the hexagon..(assuming the weather allows of course)

typed on my mobile with Tapatalk

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Just did a 3x drizzle image ... have to use very high wavelets did the auto balance and get a very blue image.

gallery_32740_2937_10608.jpg

Used Gamma setting to reduce the blue, but still have some blue fringes ... I will investigate colour noise reduction in image analyser.

Thanks for the tips so far all helps in the quest.

Colour noise reduction wont work unless you use auto rgb align first Chris. The problem with using such heavy wavelets on the 3x drizzle is you are narrowing the rings considerably and losing the round globe of the planet. The signal to noise ratio is too weak at 3x in my opinion resulting in the use of excessive sharpening and noise reduction.

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Thanks for the advice.

That makes sense, this is why I am struggling with drizzle on my Jupiter images where much better signal is needed to pull out the details on the planet. Other than better seeing and transparency. What else can I do to increase signal reduce noise.

Bigger scope?

More images?

Cooler camera?

Mono camera?

What is the best bang for buck?

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You did well to capture Saturn so early. The seeing is going to be the key to getting a good image this year.

Had a bit of a play with your image whilst waiting for my dinner to cook, only a few mins work in R6 etc but I think it helps to show the importance of using the RGB align as Stuart has commented on a couple of times. It really is a must with all colour cam images and is even more important when the target is so low.

post-7987-0-49893500-1389207622_thumb.pn

Hope you get some decent weather to get out again soon.

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