First M42 with 250p

[yelsac]

Finally managed to get guiding sorted on the 250p

This is just 6x300 lights

& 5x30 for the core all taken at iso 400 with no calibration frames (completely forgot!) stacked in DSS, processed in CS3 & Gimp2

Its a bit to Magenta, I'm struggling with processing in CS3 still learning

Any advice/tips greatly welcomed

thanks for looking

[graemlourens]

Hi

I think the detail is very nice for that exposure time, the core has an interesting touch to it!. The colors are rather shifted but i'm sure somebody here can tell you how to color calibrate it in photoshop (i'm a pixinsight user myself)

The color calibration should be done right as one of the first steps before other processing. It seems your starcolor disappeared - did this happen while processing or already in the raws you don't have any color left in the stars (blown out?)

Kind regards, Graem

[yelsac]

25 minutes ago, graemlourens said:

Hi

I think the detail is very nice for that exposure time, the core has an interesting touch to it!. The colors are rather shifted but i'm sure somebody here can tell you how to color calibrate it in photoshop (i'm a pixinsight user myself)

The color calibration should be done right as one of the first steps before other processing. It seems your starcolor disappeared - did this happen while processing or already in the raws you don't have any color left in the stars (blown out?)

Kind regards, Graem

Thanks Graem for the comments

Yes I think the color went in processing I think I oversharpened in sharpmask (still not to sure how/what process is best!) Not sure what you mean when you say colors are shifted, do you mean the colors are to different from the core to the outer? 

So is it better to do the colors before the levels/curves?

Regards

 

[laudropb]

Very nice image.

[graemlourens]

Hi.

With shifted i meant that maybe (its difficult to say without analyzing the raw image you have) the general levels of red / green / blue have not been 'equalized' yet. With OSC DSLR pics i always had a heavy red inside (due to light pollution) that you correct at the beginning before you continue processing, or else you've got one color that will bias your whole image. If you take mono images separately, you also have to 'balance' them before (or after) you combine them as red will mostly be more dominant (at least in my case with light pollution)

If you can share a Tiff (or fits) file, i am happy to quickly have a look at it, preferrably the original stacked one (before stretching) and the one you presented at the top.

Olly can probably say more here about the true colors of M42, he nearly ripped me apart for having wrong color in my last image (still trying to correct it!) :))))

Kind regards, Graem

[MARS1960]

Well done, better than my effort.

Here's some great tips by Jerry Lodriguss, just click next or back for more tutorials.

http://www.astropix.com/HTML/J_DIGIT/DIGTECHS.HTM

[yelsac]

6 hours ago, graemlourens said:

Hi.

With shifted i meant that maybe (its difficult to say without analyzing the raw image you have) the general levels of red / green / blue have not been 'equalized' yet. With OSC DSLR pics i always had a heavy red inside (due to light pollution) that you correct at the beginning before you continue processing, or else you've got one color that will bias your whole image. If you take mono images separately, you also have to 'balance' them before (or after) you combine them as red will mostly be more dominant (at least in my case with light pollution)

If you can share a Tiff (or fits) file, i am happy to quickly have a look at it, preferrably the original stacked one (before stretching) and the one you presented at the top.

Olly can probably say more here about the true colors of M42, he nearly ripped me apart for having wrong color in my last image (still trying to correct it!) :))))

Kind regards, Graem

Hi thanks again for your imput heres the original Tiff

m42 250p.TIF

I think going back to your original thought that I might have lost the stars color after stacking in DSS I tweaked it a bit in DSS before saving. I never know with the final histogram in DSS after it has stacked the images if I should align the red/green/blue lines at the base of the curve (that probably makes no sense at all) or just save it.

 

 

[yelsac]

2 hours ago, MARS1960 said:

Well done, better than my effort.

Here's some great tips by Jerry Lodriguss, just click next or back for more tutorials.

http://www.astropix.com/HTML/J_DIGIT/DIGTECHS.HTM

Wow brilliant I will certainly have a read of that, thats just the sort of basic intro I need

thanks

[MartinB]

Lots of lovely nebulosity.  In CS3 go into colour balance (ctrl ), check highlights and preserve luminosity buttons and move the magenta/green slider over to the right until nicely cooked

[graemlourens]

Hey.

Thx for the TIF, could you still send me the File that came out without adjustments directly from DSS? Looking at the image you posted ( i'm still wondering about the star color), it is difficult to see if and how the color channels are balanced, as nowhere in the image you can get a piece of true 'background' (as around M42 there is still a lot of nebulosity). But as Martin suggested you can just do it manually, and compare maybe to images you can find on astrobin.com or google to compare.

I only used DSS in the early beginnings and then rather fast switched to Pixinsight. But in DSS i read a lot that you should just export the unstretched unmodified stacked image (that will look totally black) and then stretch and manipulate it directly in Photoshop (lots of tutorials around)

The possibilities in DSS are very basic and i wouldn't get use to only using those, rather do it from scratch in a program like photoshop or Pixinsight. Its worth the learning curve, but obviously will take some time. I guess i watched around a million hours of youtube tutorials until i finally had it sorted out with levels, curves and histograms  

I guess if you still make flats (more important in my opinion that darks & bias on this target as its very bright) and you make maybe another 6 pictures you will have very nice data to process. Stacking algorithms tend to have an exponential effect as soon as you get to around 6-15 (good) frames based on my experience and literature.

Kind regards, Graem

[yelsac]

9 hours ago, graemlourens said:

Hey.

Thx for the TIF, could you still send me the File that came out without adjustments directly from DSS? Looking at the image you posted ( i'm still wondering about the star color), it is difficult to see if and how the color channels are balanced, as nowhere in the image you can get a piece of true 'background' (as around M42 there is still a lot of nebulosity). But as Martin suggested you can just do it manually, and compare maybe to images you can find on astrobin.com or google to compare.

I only used DSS in the early beginnings and then rather fast switched to Pixinsight. But in DSS i read a lot that you should just export the unstretched unmodified stacked image (that will look totally black) and then stretch and manipulate it directly in Photoshop (lots of tutorials around)

The possibilities in DSS are very basic and i wouldn't get use to only using those, rather do it from scratch in a program like photoshop or Pixinsight. Its worth the learning curve, but obviously will take some time. I guess i watched around a million hours of youtube tutorials until i finally had it sorted out with levels, curves and histograms  

I guess if you still make flats (more important in my opinion that darks & bias on this target as its very bright) and you make maybe another 6 pictures you will have very nice data to process. Stacking algorithms tend to have an exponential effect as soon as you get to around 6-15 (good) frames based on my experience and literature.

Kind regards, Graem

Graem really appreciate you taking the time to reply

unfortunately it won't seem to let me upload any more files as it states I can only upload a maximum of 20MB (not to sure how long that lasts until it resets!)

The sort of screen I see after DSS has finished, its very bright without moving the Histogram around to see the picture get clearer & darker. Sometimes like you stated before one of the colors lines is way off the other two so I try to move it so they are roughly together at the base of the curve & then save it

I will keep trying though

 

[graemlourens]

In DSS that image is a pre-streched image, but when you saving you can save (i'm not sure exactly how the option is called) without 'applying any changes' (but integration them i think it sais) something like that it sais.

I would select this option. When you look at what was saved, it will look pretty much totally black (as its not been stretched yet). That would be the interesting 'raw' to look at for me to see few things. In processing there are lots of things you (should, but not have to) do before you 'stretch' it. Stretching is taking the image from a linear (for our eye, not really usable) image to the stretched state where you are making the dark subtle differences more visible to our eye.

Stretching though is an non-reversable process and as soon as you have done that you have changed the picture so that you do not know the real values anymore of certain pixels. You will see in processing a lot the notion that you are doing this 'in a linear state' so you're relying on that you're image contains the 'real' values taken from your camera.

Btw if i'm stating the obvious for you please tell me so, i don't know how much you have already found out by yourself. I just remember that this stage for me was the most important so i'm glad to help and give back what others gave me a while ago.

If you have Dropbox or smth similar just upload it there and share the link with me. We can also happily continue this via private MSG if you wish to not clog up the thread.

Kind regards, Graem

[yelsac]

57 minutes ago, graemlourens said:

In DSS that image is a pre-streched image, but when you saving you can save (i'm not sure exactly how the option is called) without 'applying any changes' (but integration them i think it sais) something like that it sais.

I would select this option. When you look at what was saved, it will look pretty much totally black (as its not been stretched yet). That would be the interesting 'raw' to look at for me to see few things. In processing there are lots of things you (should, but not have to) do before you 'stretch' it. Stretching is taking the image from a linear (for our eye, not really usable) image to the stretched state where you are making the dark subtle differences more visible to our eye.

Stretching though is an non-reversable process and as soon as you have done that you have changed the picture so that you do not know the real values anymore of certain pixels. You will see in processing a lot the notion that you are doing this 'in a linear state' so you're relying on that you're image contains the 'real' values taken from your camera.

Btw if i'm stating the obvious for you please tell me so, i don't know how much you have already found out by yourself. I just remember that this stage for me was the most important so i'm glad to help and give back what others gave me a while ago.

If you have Dropbox or smth similar just upload it there and share the link with me. We can also happily continue this via private MSG if you wish to not clog up the thread.

Kind regards, Graem

Graem

Thanks, that really makes sense, I will save it without any changes & have another go.

I've never tried it that way. I've uploaded it to dropbox, I didn't change a thing on it the color wasn't all lined up, its not entirely black but not white as I've been used to heres the link  https://www.dropbox.com/s/72udid6g0qi2h1q/2.TIF?dl=0

 

[yelsac]

1 hour ago, graemlourens said:

In DSS that image is a pre-streched image, but when you saving you can save (i'm not sure exactly how the option is called) without 'applying any changes' (but integration them i think it sais) something like that it sais.

I would select this option. When you look at what was saved, it will look pretty much totally black (as its not been stretched yet). That would be the interesting 'raw' to look at for me to see few things. In processing there are lots of things you (should, but not have to) do before you 'stretch' it. Stretching is taking the image from a linear (for our eye, not really usable) image to the stretched state where you are making the dark subtle differences more visible to our eye.

Stretching though is an non-reversable process and as soon as you have done that you have changed the picture so that you do not know the real values anymore of certain pixels. You will see in processing a lot the notion that you are doing this 'in a linear state' so you're relying on that you're image contains the 'real' values taken from your camera.

Btw if i'm stating the obvious for you please tell me so, i don't know how much you have already found out by yourself. I just remember that this stage for me was the most important so i'm glad to help and give back what others gave me a while ago.

If you have Dropbox or smth similar just upload it there and share the link with me. We can also happily continue this via private MSG if you wish to not clog up the thread.

Kind regards, Graem

Sorry me again, here's a link to a small (very small) jpg of what the histogram looks like after DSS has finished without me doing anything just before I save it

https://www.dropbox.com/s/5l6s5leduk5bcys/DSS.jpg?dl=0

[graemlourens]

Hi.

Thx, i looked at the file and its as usual - the red channel is overwhelming the image due to light pollution (normal). But i can nearly not believe that that is the unstretched image. When you click 'Save' in DSS, which of the 2 options did you select 'Embed but don't apply' ?

In the attached screenshot i marked the setting with blue.

If the histogram in your screenshot is unmodified, then i guess you're exposing a little too long. With DSLR you should expose until the big 'walls' are around 1/3 until max half of your histogram. Those big 'walls' are the background. But btw: what you got ouf of that tif you attached is already very good, don't get me wrong. I'd just try to get to that stage without using DSS image manipulation in future. Or else you're 'stuck' with DSS forever.

Kind regards, Graem

[yelsac]

2 hours ago, graemlourens said:

Hi.

Thx, i looked at the file and its as usual - the red channel is overwhelming the image due to light pollution (normal). But i can nearly not believe that that is the unstretched image. When you click 'Save' in DSS, which of the 2 options did you select 'Embed but don't apply' ?

In the attached screenshot i marked the setting with blue.

If the histogram in your screenshot is unmodified, then i guess you're exposing a little too long. With DSLR you should expose until the big 'walls' are around 1/3 until max half of your histogram. Those big 'walls' are the background. But btw: what you got ouf of that tif you attached is already very good, don't get me wrong. I'd just try to get to that stage without using DSS image manipulation in future. Or else you're 'stuck' with DSS forever.

Kind regards, Graem

Graem

Yes thats the box I checked for the file in dropbox after your advice although I didn't with the original image, I changed the red line & a few other things in DSS & clicked apply adjustments.

With regards to the red line(light pollution) I take it you wouldn't move it in DSS rather just sort it in Photoshop

Its all good advice I will keep learning

thanks Yelsac

[graemlourens]

Hi Yelsac.

Ok, if i understand correctly, you loaded that image back into dss and then saved it again, but that already 'too late' as it has been stretched. (But maybe i understood you wrongly)

You would have to re-stack (do the whole process again in DSS) and then save it according to what i said, without doing any changes to it, thats the point when you transfer to another program (like Photoshop or Pixinsight) and process things still in the linear state, and then go 'non-linear' with stretching.

Kind regards, Graem

[yelsac]

3 hours ago, graemlourens said:

Hi Yelsac.

Ok, if i understand correctly, you loaded that image back into dss and then saved it again, but that already 'too late' as it has been stretched. (But maybe i understood you wrongly)

You would have to re-stack (do the whole process again in DSS) and then save it according to what i said, without doing any changes to it, thats the point when you transfer to another program (like Photoshop or Pixinsight) and process things still in the linear state, and then go 'non-linear' with stretching.

Kind regards, Graem

Graem

No I did do a complete restack from the begining, saved it without changes & then put it on dropbox. Mind you this is the first attempt at guiding & taking lights with the 10" scope so I may not have done it all correctly. I think I'm wanting to learn the stack process- what to do & more importantly what not to do! Followed but getting others advice on what process(order of doing things) to take within Photoshop

regards

Yelsac

[graemlourens]

Hi Yelsac.

Ok great, then you did everything correctly and thats the starting point in photoshop to continue. I would now just google around for a few good photoshop tutorials.

I'm jealous of your 10", enjoy it!