Bubble Nebula Ha

[Rodd]

2 hours ago, ollypenrice said:

It's very good, no doubt at all. Even with the data you have the image could stand a good bit of extended processing, I think. (Well, I'm sure.) It has even more to give - but processing is always a long story!!

Olly

Thanks Olly--I was able to shoot some darks last night due to clouds and I calibrated the data and was amazed at how much better it is--Just a full calibration with 21 darks, 33 flats and 400 biases makes a noticeable difference.  Provides a much better starting point.   I find processing to be a series of negotiations with the data.... every positive effect seems to have some degree of an unwanted side effect(s).  I guess the skill is getting the benefits without the deleterious effects.  

[johnrt]

9 hours ago, Rodd said:

I find processing to be a series of negotiations with the data.... every positive effect seems to have some degree of an unwanted side effect(s).  I guess the skill is getting the benefits without the deleterious effects.  

Yes, you should look to think of your data as a set of zones, each require processing in a different way - low / medium / high signal. The trick to success is applying the appropriate processing to only the zone that requires it, selective processing!

Unfortunately in Pixinsight this means wresting with and mastering the autistic world of masks & pixelmath as you do not have all the benefits of layers and blending.

[Rodd]

3 hours ago, johnrt said:

Yes, you should look to think of your data as a set of zones, each require processing in a different way - low / medium / high signal. The trick to success is applying the appropriate processing to only the zone that requires it, selective processing!

Unfortunately in Pixinsight this means wresting with and mastering the autistic world of masks & pixelmath as you do not have all the benefits of layers and blending.

I hear the Gimp2 is supposed to be Photoshopesque--I have the Gimp2.  Haven't played with it yet.  

[Rodd]

On ‎7‎/‎24‎/‎2016 at 13:00, Barry-Wilson said:

A great start and beautiful Ha image in its own right Rodd.

This looks well processed and shows you are beginning to familiarise yourslef with the multitude of techniques from capture to processing.

Good stuff and I look forward to seeing this image develop.

 

18 hours ago, ollypenrice said:

It's very good, no doubt at all. Even with the data you have the image could stand a good bit of extended processing, I think. (Well, I'm sure.) It has even more to give - but processing is always a long story!!

Olly

 

On ‎7‎/‎25‎/‎2016 at 09:39, swag72 said:

This target works nicely in NB...... go for it Rodd

 

On ‎7‎/‎25‎/‎2016 at 09:32, PatrickGilliland said:

Hi Rodd

That's looking excellent with that detail and focal length crying out for more NB data - i think RGB would soften all that lovely detail back out which would be a shame to lose.

Paddy

 

On ‎7‎/‎22‎/‎2016 at 14:57, johnrt said:

Make sure you have the chrominance noise reduction checked in the LRGB combine tool, I don't shoot any SII but yes essentially it's correct.

Process both your colour combined image (be quite aggressive here) and your mono Ha image (be nice and gentle with it) and then add the Ha over the colour as Luminance. I generally remove the stars from the colour image, this gives really tight small stars, but the cost of any colour (which I don't really care about).

 

 

On ‎7‎/‎22‎/‎2016 at 12:28, Maximidius said:

Thanks for the Reply Rodd

I'm no expert, but I can see the logic and rationale for the case of more data. It will definitely help the snr but as i understand it, with diminishing noticeable results as the number of frames increase. However, more frames most certainly help with the dynamic range. Besides, having the ability to select only the best for FWHM, Median and eccentricity is certainly a luxury i'd like to have, but i seldom have the time to make that many images. I remember reading the Garbage in garbage out experiment, it was interesting and quite cool for the likes of me who get very little quality imaging time. Sara certainly produces some fantastic images, i think her results speak for themselves. Which in a way kinda helps with the dilemma . From that point of view it can't do any harm to keep plugging away, especially if you want to chase those subtle details. 

I guess the limitations are more to do with personal investment, if you don't mind and you're not losing sleep, then it's no problem, if you're staying out all night and having to set up each time, there has to be a cut-off point. That being said - I know we can always do with more data; i'm not sure, but i suspect we can never have too much.

Whatever you do you have 10hrs now, combined with the other data (once collected) you'll be knocking on the door of 20hrs+(?). You certainly can't sniff at that! And as it stands it is a fantastic image. 

Thanks everyone for the input and support.  Here is the Ha image I will be proceeding with--40 20min subs (I added 10), fully calibrated (21 darks, 33 flats 400 bias), drizzle integrated.  I was amazed at the impact calibration had on the stack (and each sub of course).  No processing has been done to this stack after integration.  The difference between the 30 sub stack and 40 sub stack is not really visible, but there is a higher SNR and less noise in the 40 sub stack (according to the sub frame selector). I hope I don't ruin it!!!

[ollypenrice]

The advantage of a deep stack over a shallow one really emerges when you start to process. Contrasts can be enhanced and details sharpened. (In fact these are very similar operations but carried out over different scales.

Olly

[swag72]

I remember some time ago making a post of things not to underestimate in imaging..... One of the things was amassing lots of data... it really DOES make a difference and also decent calibration frames. From there it's much planer sailing

[ollypenrice]

It certainly is. I am also convinced that long subs beat short ones. There are some kinds of noise, like slight large scale banding, that long subs alone will take care of.

Olly