M42 First Attempt with DSLR

[SnakeyJ]

First night out imaging with DSLR (EOS1100D unmodded):

I'm using the SW CC so shooting at 900mm fl on the Exp 200P - I took bracketed exposures of 15s, 30 sec and 60 sec @ ISO800.   The image is composed in three layers with a stack of 20 exposures for the core and ineer area of the nebula and a stack of only 8 frames for the rest of the image, as the battery ran out on the last run!   I've calibrated with Darks and Bias, though my first experiment with using the laptop monitor for flats proved too uneven and these were discarded.

Captured with APT, stacked in DSS, quick stretch and tidy in Neb3 and the HDR done (roughly) using Gimp 2.8.8.   I need some more time to play with the levels and feathering to get a less obvious merge - but otherwise very pleased with the response and level of detail comming through on these short subs.    Also pleased with the guiding, which was done with the QHY5L-IIM in PHD2 beta.   The coma corrector also seems to be doing its work and the star shapes look pretty good for a night of fair seeing - though would like some longer subs to bring in some detail on the running man nebula.

I also got a fair amount of data on M33, though 2min x ISO800 wasn't long enough on this target - another attempt to follow as soon as the skies permit.

[Space Ranger]

Very nice!

[Zuben Elgenubi]

Lovely image. I imaged M42 for the first time on Friday and I'm reasonably pleased with the result but as I was using 120 second subs the core is totally over-exposed.

If you don't mind me asking, how do you process your image when using subs of different lengths? Do you stack all your lights together or do you do each exposure length separately? Presumably you also take darks for each sub length? Thanks.

Gareth

[Stargazer33]

Very nice image Jake!

You could try layering just one of your shorter subs and then do a layer mask to just reveal the area around the central four stars of the trapezium. That would stop them from being burnt out.

I was hoping to get out tonight as the sky here is clear now, but looking at the Met radar images there is a whole heap of cloud moving in for tonight again!

[SnakeyJ]

Lovely image. I imaged M42 for the first time on Friday and I'm reasonably pleased with the result but as I was using 120 second subs the core is totally over-exposed.

If you don't mind me asking, how do you process your image when using subs of different lengths? Do you stack all your lights together or do you do each exposure length separately? Presumably you also take darks for each sub length? Thanks.

Gareth

Gareth - thanks, have to have a look and see if your image is posted up here.     The core responds well around 10-15 sec exposure @ ISO 800 on my 1100D - a very bright object as DSO's go!     Re the processing, I did different darks for each exposure stacking about 20 to create the master dark.   However you can use the same bias and flat frames against different exposure lengths.    Using APT I set up a lan to do all of my darks at the end of the night, just parked the scope and left the camera/laptop running which saved wasting valuable imaging time.

Re processing for this Ollypenrice recently posted a great tutorial link recently in JohnC64's M42 and Running Man thread

Although this is specifically about photoshop the concepts are directly transferable to Gimp.

I'm only just starting out on the processing side, but worth searching back through historic threads as you come to try these targets - lots of excellent tips and advice from some really experienced imagers.

[SnakeyJ]

Very nice image Jake!

You could try layering just one of your shorter subs and then do a layer mask to just reveal the area around the central four stars of the trapezium. That would stop them from being burnt out.

I was hoping to get out tonight as the sky here is clear now, but looking at the Met radar images there is a whole heap of cloud moving in for tonight again!

OK - I have a confession at this point, although I've heard frequent mention of the trapezium I wasn't entirely sure and had to look it up.

These are quite burned out on my stretched and processed 15 sec sub, so will have to produce a less stretched one as another layer - I shall add this to my mission tonight of improving the layer masks and gradients.

[SnakeyJ]

I was hoping to get out tonight as the sky here is clear now, but looking at the Met radar images there is a whole heap of cloud moving in for tonight again!

Same here, looks to be clouding up after 22:00hrs - looking ahead Tuesday night looks ok currently according to the Met and 7Timer.    It is a work night, but might might leave a plan running in APT and see if it will park my scope at the end of the session

[Zuben Elgenubi]

Gareth - thanks, have to have a look and see if your image is posted up here.     The core responds well around 10-15 sec exposure @ ISO 800 on my 1100D - a very bright object as DSO's go!     Re the processing, I did different darks for each exposure stacking about 20 to create the master dark.   However you can use the same bias and flat frames against different exposure lengths.    Using APT I set up a lan to do all of my darks at the end of the night, just parked the scope and left the camera/laptop running which saved wasting valuable imaging time.

Re processing for this Ollypenrice recently posted a great tutorial link recently in JohnC64's M42 and Running Man thread

Although this is specifically about photoshop the concepts are directly transferable to Gimp.

I'm only just starting out on the processing side, but worth searching back through historic threads as you come to try these targets - lots of excellent tips and advice from some really experienced imagers.

Thank you for the info Jake, I shall have a read.

I've just uploaded my M42 to my gallery. I only started imaging this summer and while I feel that I am beginning to get my head around actually acquiring the images, I am finding the learning curve of processing to be a challenge as my knowledge of computers and software is rather limited. I'm sure I can only get better! Next challenge: guiding...

[SnakeyJ]

You could try layering just one of your shorter subs and then do a layer mask to just reveal the area around the central four stars of the trapezium. That would stop them from being burnt out.

Bryan - I had a look at this, but in the single subs (15sec/ISO800), the trapezium stars are burnt out/bloated.

 (Straight debayer of RAW sub with no calibration or post process - PIPP used to do the Debayer)

I'm very keen to improve on the image, so hope to have another go at this tomorrow night and will do some 10 sec ISO400 subs to see how this goes.    I also want to get some more 60 sec and some 120 sec subs to reduce noise and bring out some more of the running man and the extended nebula.    Keen to see what I can get before plucking up the courage for the first mod - removal of the WB filter.

[Daniel-K]

Jake good job i bet if you do a selective colour  red  and move the cyan slider all the way to left you will get some more detail. give it  a go

[SnakeyJ]

Jake good job i bet if you do a selective colour  red  and move the cyan slider all the way to left you will get some more detail. give it  a go

Cheers Daniel,

I had redone the composition to improve the core merge and was about to upload before catching this post.   I've now modded the image to include the boost to red saturation with the colour select tool (which was a new discovery for me - thanks for the tip).    I have overdone this a little to draw out the nebula detail, bringing a red gradient to the whole image.    Though I think some more practice on selection and subtle use could really help.

Looking at the other M42 dslr images within the forum I have some way to go, and the filter removal will really help with the red capture.     Very pleased though with the resolution, sensitivity and pleasantly surprised by the noise levels on these exposures (especially as the main image area is from a stack of only 8 exposures).   The coma corrector also seems to be doing a good job, so hope to get some more widefield shots and practice/develop my processing skills.

[Quatermass]

Very Nice and a joy to image this one.

[SnakeyJ]

Very Nice and a joy to image this one.

Thanks Mark - definitely enjoying imaging with the DSLR and it's bigger fov than the QHY.   Hopefully next year my revisits will show as much improvement as the M81 on your blogg.   Really nice to see these comparisons.

[robbie c]

That's a cracking image well done Jake 

[Quatermass]

Get that red filter out and it will be even better when I modded my cannon 350d it made a big difference.

Sent from my Nexus 7 using Tapatalk

[WaveSoarer]

Great image and very nice colours.

[Sandancer10]

Great image and I like the second posting with the increased red.  I photographed M42 over a week ago and have been struggling with DeepSky Stacker as my DSLR was not compatible. Finally sorted it out today thanks to very good advice from the guys at the local Astro club and I'm quite overawed with seeing the result of my work on the laptop.  It's wonderful to be doing all this, but I'm still working on the images so can't post anything yet.

Good luck with your imaging.

[Big_Daz]

Great image capture.

[wxsatuser]

Well done Jake.

[SnakeyJ]

Get that red filter out and it will be even better when I modded my cannon 350d it made a big difference.

Sent from my Nexus 7 using Tapatalk

I'm trying to man up for the mod this weekend - though might take the camera in to work for some peace and quiet away from the chidlets  

Great image and very nice colours.

Thanks - I'm working on it, though plenty more practice required.   The processing side is far more technical and difficult than capturing the photons!

Great image and I like the second posting with the increased red.  I photographed M42 over a week ago and have been struggling with DeepSky Stacker as my DSLR was not compatible. Finally sorted it out today thanks to very good advice from the guys at the local Astro club and I'm quite overawed with seeing the result of my work on the laptop.  It's wonderful to be doing all this, but I'm still working on the images so can't post anything yet.

Good luck with your imaging.

Thanks - that was all down to Daniel's help!   My 1100D RAW files wouldn't work in the release version of DSS, though the forums soon provided the link to the newer Beta which properly supports the RAW/CR2 format.    If you do have conversion issues like this in future I can strongly recommend Chris Garry's PIPP and Irfanview, which both offer excellent batch conversion routines.

Great image capture.

Cheers Daz - first of many, provided the weather gods permit.

Well done Jake.

Thanks Mike - you stayed up for the early morning shift, hope conditions were favourable