What am i doing wrong?

[MARS1960]

Here is a png of M51,  5 x 600s subs taken with my new 100ED DS and a canon 70D stacked in DSS, am i just not capturing enough data?

TIA.

 

[cuivenion]

Looks like you need to align the three colour channels at the point the curve starts to go up.

[Steve Ward]

Would love to help , but am not going to download files unnecessarily just to view an image , attach as a PNG and it will automatically display in the post ...

You will undoubtedly get a better response this way.

[MARS1960]

1 minute ago, Steve Ward said:

Would love to help , but am not going to download files unnecessarily just to view an image , attach as a PNG and it will automatically display in the post ...

You will undoubtedly get a better response this way.

ok thanks.

[MARS1960]

[MARS1960]

13 minutes ago, cuivenion said:

Looks like you need to align the three colour channels at the point the curve starts to go up.

Thanks,

Thats exactly what i did so i cant understand what iv'e done wrong

[cuivenion]

Here's some screenshots. Please note that a lot of people don't do any editing in DSS and save without adjustments. They do their processing in different software. It's a good way to get a quick look at the data though.

 

[wornish]

Just done a quick FTS Autostretch on your TIF.

 

Good news -  the stars are in focus as is M51.

Not so good - You have some serious dust spots on your lens.

and there is an amazing amount of noise in the image.

What ISO did you use ?

 

 

[cuivenion]

just to add you'll need to boost saturation about 15-18% to get the colour.

[MARS1960]

Thanks wornish, ISO 400

Thanks cuivenion.

[spillage]

Hi,

I would suggest at least iso800 but find my 1100d better at iso1600 depending on conditions. But I would take more lights at least 15-30 at around 90 second exposure.

cheers

spill.

 

[wornish]

Apart from the comments above about colour channel alignment after stacking I think the problem is you need more data.

I would up the iso to 800  

take some Darks as well as more lights.

[MARS1960]

Ok, thanks guys, hopefully get another clear night soon and i'll have another go at it using your suggestions.

[RuralBill]

Make sure you tick the box that says "embed changes but do not apply them" and don't do any processing in DSS move the image to PS or Gimp or whatever you use, do a couple of runs of levels and curves and you will see the image coming out.

if you apply the changes that DSS makes you will loose a huge amount of data, don't ask me why but it will not work, and you end up with a grey image with lack of colour....

hope that helps

Bill

[almcl]

The dust bunnies and any vignetting might be reduced if you are able to take some flats to feed into DSS.  If not, centering the image (tricky, I know, with such a faint target) and then cropping it may help.

[MARS1960]

20 hours ago, RuralBill said:

Make sure you tick the box that says "embed changes but do not apply them" and don't do any processing in DSS move the image to PS or Gimp or whatever you use, do a couple of runs of levels and curves and you will see the image coming out.

if you apply the changes that DSS makes you will loose a huge amount of data, don't ask me why but it will not work, and you end up with a grey image with lack of colour....

hope that helps

Bill

Thanks Bill, i will give that a try.

[MARS1960]

21 hours ago, RuralBill said:

Make sure you tick the box that says "embed changes but do not apply them" and don't do any processing in DSS move the image to PS or Gimp or whatever you use, do a couple of runs of levels and curves and you will see the image coming out.

if you apply the changes that DSS makes you will loose a huge amount of data, don't ask me why but it will not work, and you end up with a grey image with lack of colour....

hope that helps

Bill

When you say no processing does that mean that i don't even align the color channels in DSS?

Thanks.

[RuralBill]

19 minutes ago, MARS1960 said:

When you say no processing does that mean that i don't even align the color channels in DSS?

Thanks.

No, there is no point and you won't be saving the changes anyway, as soon as you have a stacked image, get straight into your processing software of choice, all you want DSS to do is stack the images and NOTHING else, all the data manipulation should be done elsewhere.

regards

Bill

[MARS1960]

1 minute ago, RuralBill said:

No, there is no point and you won't be saving the changes anyway, as soon as you have a stacked image, get straight into your processing software of choice, all you want DSS to do is stack the images and NOTHING else, all the data manipulation should be done elsewhere.

regards

Bill

That's great Bill, thanks for your help.

[RuralBill]

One thing I forgot to mention is when saving the image in DSS you should save in 8 bit, I think I have that correct and someone please correct me if I am wrong there.....!!, 

Bill

[Steve Ward]

Save in 16 bit ....

[RuralBill]

38 minutes ago, Steve Ward said:

Save in 16 bit ....

Ok, I stand corrected, ignore my last post

Bill

[dph1nm]

On 20/08/2016 at 14:04, RuralBill said:

Make sure you tick the box that says "embed changes but do not apply them" and don't do any processing in DSS move the image to PS or Gimp or whatever you use, do a couple of runs of levels and curves and you will see the image coming out.

if you apply the changes that DSS makes you will loose a huge amount of data, don't ask me why but it will not work, and you end up with a grey image with lack of colour....

Don't understand this - if you are using 8-bit GIMP then I recommend you always process first in DSS and save that, otherwise you will lose most of the data (as GIMP tries to compress the full range of the linear data in the 16-bit DSS files down into 8-bits).

NigelM

[MARS1960]

3 minutes ago, dph1nm said:

Don't understand this - if you are using 8-bit GIMP then I recommend you always process first in DSS and save that, otherwise you will lose most of the data (as GIMP tries to compress the full range of the linear data in the 16-bit DSS files down into 8-bits).

NigelM

I don't understand it as such either but Ollypenrice  agrees with the statement so that's plenty good enough for me. 

I use PS in 16-bit mode for my processing.

[wimvb]

Gimp is for 8 bit/channel images, such as jpeg.

Gimp 2.9 can handle 16 bit/channel, but is an unofficial release.

PS can handle 16 bit/channel

Stack in DSS, don't apply changes if you have a program that can handle 16 bit images. If you only have the 8 bit standard version of Gimp (v 2.8 I believe), you will need to stretch in DSS before importing in Gimp.

Hope I have this right, because I don't do it this way anymore. If not, please correct me.