Stacking

[djs44]

Not sure if am posting in correct place.I have tried  stacking for the first time using registax,after 3 hours i am getting no where.First of all i find it hard to get more then one  image  up,and more often then not there is no set alignment on screen,ok on the odd occasion it has popped up so mo idea what i am doing wrong there.I have followed or tried to from some instructions on You Tube.The other problem i have has is when i click stack nothing happens at all.

                                                                                                                        The order i have been trying to stack is Select image usually just the one is all i can  get up,then assuming it is on the screen i click set alignment points,ithen bring the slider down to say 25,then i click limit stack wavelet do all save image i get nothing at all,and more often the stack does nothing on the percentage bar.Finding this a tad frustrating    DEREK

[Cornelius Varley]

What type of image format are you trying to stack ?

[djs44]

Moon images Cornelius

[Cornelius Varley]

4 minutes ago, djs44 said:

Moon images Cornelius

Jpg, tiff , bmp, avi ?

[djs44]

4 minutes ago, Cornelius Varley said:

Jpg, tiff , bmp, avi ?

Jpeg

4 minutes ago, Cornelius Varley said:

Jpg, tiff , bmp, avi ?

 

[Freddie]

JPEG is not the best to stack, you would be better off with an AVI, but you have what you have.  When you say you “get one image up” does that mean you are only loading one image? If so, you need to load multiple images to allow Regi to stack these multiple images together.

[djs44]

i can convert photos to AVi i tried loading several image but it only takes one for some reason

[JamesF]

What did you use to create these images?  Are they from a DSLR?

James

[djs44]

12 minutes ago, JamesF said:

What did you use to create these images?  Are they from a DSLR?

James

Yes from a dslr but i have no movie function on camera canon 40D

 

[don4l]

How many images are you trying to stack?

[djs44]

6 minutes ago, don4l said:

How many images are you trying to stack?

was trying to stack 4 but can only get one onto rgistax for some reason been told jpeg is no god for stacking

 

[JamesF]

In my experience Registax often struggles with DSLR images, though I've never tried it with JPEGs (I always work from RAW files when using a DSLR).  I would be inclined to give AutoStakkert! a try instead for the stacking and then use Registax just for the wavelet processing though again I have no idea what it will do with JPEG images.

Something else to keep in mind for next time is PIPP, which can pre-process image files into various formats and crop frames down where the target doesn't fill the entire frame to make processing faster.

In general though there's no need to use AVI files.  They're just a convenient container for lots of frames.  Registax will work with lots of separate image frames, but it may not be entirely reliable once the frame sizes get large.

JPEG isn't very good for imaging because the creation of a JPEG image throws data away on the grounds that it can be approximated when the image is recreated, but approximation really isn't what you're after when you're trying to stack images to improve the quality of the data.

I wrote a full disc lunar imaging "how to" years ago that might be of help.  I'll see if I can find it again.

James

[JamesF]

Here you go: 

I do use Registax in that example, but it can still be the case that it struggles with DSLR images and that using AutoStakkert! for stacking and then Registax for post-processing may be the best way forward.

James

[Cornelius Varley]

7 hours ago, djs44 said:

was trying to stack 4 but can only get one onto rgistax for some reason been told jpeg is no god for stacking

 

Can you bundle them together as zip file and maybe someone can take a closer look at them.

[don4l]

8 hours ago, djs44 said:

was trying to stack 4 but can only get one onto rgistax for some reason been told jpeg is no god for stacking

 

The only reason that jpeg is no good for stacking is that jpegs have already lost some of the data, so you could get a better result using a different format.  However, this is irrelevant if you cannot get stacking to work at all.

I wonder if you wouldn't be better off using something like Deepskystacker to stack these images?

 

[djs44]

12 minutes ago, don4l said:

The only reason that jpeg is no good for stacking is that jpegs have already lost some of the data, so you could get a better result using a different format.  However, this is irrelevant if you cannot get stacking to work at all.

I wonder if you wouldn't be better off using something like Deepskystacker to stack these images?

 

I am new to all this from what i see on my canon there is 2 quality raw and jpeg or am i wrong ?.I have only took a few shots of the moon liked what i saw but wanted to enhance the photos.Is there a min limit to amout of images to stack ?

[carastro]

I find Registax doesn't like too many DSLR images uploaded at a time or it crashes.  But I have stacked Moon images in the past.  

I found the best way was to stack 2 lots of 2 frames, then stack the resulting two stacks.

Are you highlighting more than one image when you try to import, if you only do one at a time it will discard the first one and replace with the second one. 

As stated, Autostakkert might do the job better, I often found Registar would misalign images even when the alignment points were marked. 

Carole

 

 

Edited November 10, 2019 by carastro

[don4l]

3 minutes ago, djs44 said:

I am new to all this from what i see on my canon there is 2 quality raw and jpeg or am i wrong ?.I have only took a few shots of the moon liked what i saw but wanted to enhance the photos.Is there a min limit to amout of images to stack ?

The minimum is two.  It depends on what you are trying to do.

I've also got a Canon, and you are correct.  It produces either jpeg, or raw.  Raw files are much bigger because they contain all the information that was collected by the CCD chip.  Jpegs have already had some processing done, and are also compressed, so they contain a lot less information.  This will become important as your imaging improves, but it is extremely unlikely that it would matter at all for your first images.

Once you start to process RAW images, then you will probably have to convert them into a format that your image processing software understands.  This might be FITS or TIFF.

 

I've used Registax in the past to process a AVI files which contained many hundreds, or even thousands of relatively small images.  It would automatically select the best images, and combine them.  In this instance, most images are rubbish, but it is too much hard work to go through them all yourself.  Registax would pick out the best 10, 20, 30 or 40% and use them.

However, when using images from a Canon, you probably want to use all of them - or you can manually choose which ones you will use.

 

 

 

[Freddie]

2 hours ago, don4l said:

The only reason that jpeg is no good for stacking is that jpegs have already lost some of the data, so you could get a better result using a different format.  However, this is irrelevant if you cannot get stacking to work at all.

I wonder if you wouldn't be better off using something like Deepskystacker to stack these images?

 

You can’t use DSS to stack images of the moon.

[JamesF]

25 minutes ago, don4l said:

Jpegs have already had some processing done, and are also compressed, so they contain a lot less information.

To expand on this, the JPEG is created from the RAW data by combining colour information from adjacent pixels to come up with a final colour for each pixel, because RAW images only have one colour per pixel (because the camera sensor only handles one colour per pixel).  White balance correction and other image transformations (perhaps black point manipulation etc.) may also be done, and the colour depth of the image is reduced (because most JPEG implementations don't support the full number of bits coming out of the camera ADC).  Finally, the code that creates the JPEG format throws away some of the data that can be reasonably approximated when the image is recreated.  Not all compression algorithms work that way -- some reduce file size without throwing data away at all -- but it's the way the JPEG format works.

From an imager's point of view, it's this twofold discarding of data that is particularly undesirable.  During the processing steps you really want the best quality data you can get, even if once processing is complete you choose to turn an image into a JPEG for display on a website (though my personal preference there is still to avoid JPEG and use PNG instead).

James

[JamesF]

1 minute ago, Freddie said:

You can’t use DSS to stack images of the moon.

Quite.  DSS needs to find stars in the image to perform alignment of the frames.

James

[don4l]

25 minutes ago, JamesF said:

Quite.  DSS needs to find stars in the image to perform alignment of the frames.

James

Ahhhh...  

I use CCDStack, and it has a very good manual alignment mode.  You just drag, rotate and scale until you can see that the frames are aligned.

Is there nothing that is freely available that will do the same?

[djs44]

15 minutes ago, don4l said:

Ahhhh...  

I use CCDStack, and it has a very good manual alignment mode.  You just drag, rotate and scale until you can see that the frames are aligned.

Is there nothing that is freely available that will do the same?

My main prob is understanding it all am very new to all this,i really thought stacking was a simple thing to.CCD stack is new one to me is it free or do you have to pay,i need some real easy  untill i get more experiance

[don4l]

1 hour ago, djs44 said:

My main prob is understanding it all am very new to all this,i really thought stacking was a simple thing to.CCD stack is new one to me is it free or do you have to pay,i need some real easy  untill i get more experiance

CCDStack isn't free and you are absolutely right to look for something easy.  That's why I didn't mention it before.

A couple of people have mentioned Autostakkert.  It is available here:-  https://www.autostakkert.com/

Why don't you put up one or two of your jpegs and people can give their opinion?

[djs44]

12 minutes ago, don4l said:

CCDStack isn't free and you are absolutely right to look for something easy.  That's why I didn't mention it before.

A couple of people have mentioned Autostakkert.  It is available here:-  https://www.autostakkert.com/

Why don't you put up one or two of your jpegs and people can give their opinion?

I did try to download autostakkert it seems you need to donate first,i am not mean but 75 years of age i have watch the pennies.I will attach a couple jpegs to this post