Noob processing help

[Zakalwe]

Really sorry for the whole noob-ishness of this....

35 images of the Orion Nebula, all taken with a DSLR in prime focus. I have varying exposures, a batch at 10 seconds, some at 1 min and some at 2 mins. I also have about 35 darks- all taken with the lens cap on, again varying exposures from 10 seconds to 2 mins.

Am I best using DeepSky Stacker or Registax? I have tried both, with rubbish results (DSS keep reporting an Out of Memory error at the end of processing......dunno why as there is plenty of resources left).

I am sure that I can make a decent image out of what I have...just need a primer to get me started.

Anyone want to help a noob?

Sample image:

[rowan46]

hello I am not an imager but I read that deep sky stacker was the best for dslr pics. there is a sub forum for imaging help. if you publish there with all the details you will certainly get help and advice ( by the way I liked your pic and would certainly have been proudto have taken it) sorry I can't be more help

[ollypenrice]

You do need to take varying exposure lengths for this object when you are aiming for an advanced workflow and final product. Most of the time just stick to a single exposure length. (That applies to 95 percent of the images I take.)

Firstly, then, you need to sort out the right darks for the right image. I don't know if you can just throw the lot into DSS but you certainly can't in the stacking software I use.

So,

1) make a stack from the short exposures with the short darks.

2) ditto for the middle subs and

3) ditto for the long subs.

Now the fancy way to combine them involves Layer Masking in Photoshop, so you use the shortest for the Trapezium stars, the middle exposures a bit further out and the faint edges come from the longest exposures. To do this, though, you will first have to coregister (align) the three stacks. Can DSS do this without combining them? I don't know. You can read about this technique here and on the same object, to boot!

Compositing 2 Different Exposures via Layer Masks

Failing that you can just ask DSS to combine your three stacks (no further darks needed of course) and see how that comes out.

There is a good Ps trick for fixing star trails, too. It is a bodge but, hey...

Rotate the image so the trails are either vertical or horizontal.

Make a copy layer.

In Layers choose Blend Mode Darken.

In FIlters go to Other - Offset

Apply the offset in the right axis for the trails, x or y, and try different values. If you are between values (1 pixel not enough, 2 pixels too much) then choose too much and then go into Edit Fade and slide it back till your stars are round. Flatten Image and you are done.

Naughty but nice!

Olly

[Zakalwe]

Thanks ollypenrice...I'll have a play and try that.

[blinky]

Use Deep Sky Stacker and you can just bung everything into the mix. It would be better to stack the different lengths individually then you can do the layer masking as Olly Says.

[carastro]

I would say DSS is the best for stacking DS objects. However it seems as though your first problem is to sort out why DSS gets out of memory (does it stop you getting a final image?) Must be very annoying after all that hard work. If you have access to more than one computer it might be worth trying DSS on a different one for the time being.

I have just done the same object with different length subs as you have (my second attempt which i shall be posting in a minute). I stacked the longer subs with the darks, flats and Bias and then separately did the shorter versions each with their own darks flats and Bias and then combined in Photoshop as described above.

I have never tried throwing the whole lot into DSS so don't know if that will work, although someeone earlier says it does. I haven't yet mastered layer and masking but have found my own way of doing the combination in layers.

Looking forward to see what you have produced once you get over these hurdles.

Carole

[swag72]

I am new to all of this and have myself taken my first Orion nebula image this week. I had a mixture of subs, lights and darks and bunged it all in DSS the worked on the results in CS3 afterwards. Produced an OK result for a first time as well.

[Zakalwe]

The pooter is a quad core Intel jobbie with 4 gig of RAM, so it should have the horsepower.

It could be because I am processing the RAW files (over 16Mb each) and selecting the 2x2 drizzle option which drastically increases the final image size?? Whatever it is, it is brassing me right off. I was chuffed to have got it all set up (used the eBay remote camera timer to control the exposures- a great bit of kit for £15).

I'll have to have a proper play with it over XMas.

Gawd I hate being dumb!

[Bizibilder]

Turn off the drizzle and then stack - that should sort out the image size. Once you have managed to process you can work on the niceties of DSS.

[Zakalwe]

Turn off the drizzle and then stack - that should sort out the image size. Once you have managed to process you can work on the niceties of DSS.