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swannies1983
05-12-2012, 11:02 PM
Given my lack of imaging for the last 6 months, I thought it would be good to really spend some time processing my old data. I've spent probably about 6 hours on this one after reading through various tutorials and trying out different techniques. I'm pretty pleased with the result and have to say, it's probably right up there with my best image so far. Still need more data to reduce the noise. As you can see in my raw sub, not a lot to work with as this region of the sky is the most light polluted region of my sky.

Details
Scope: 8" Newt
Mount: EQ6
Guide scope: 60mm f/11 tasco refractor
Guide camera: unmodded Toucam
Guiding software: PhD
Imaging camera: unmodded Canon 400D
Settings: about 6hrs of data made up for 480 and 600sec subs @ ISO800 and ISO1600
Stacked in DSS and processed in CS3.

First image shows final result and second image shows a raw sub (600secs @ ISO1600).

tilbrook@rbe.ne
05-12-2012, 11:17 PM
Oustanding Dan!!

Detail is remarkable, I'll have to lift my game after looking at this.

Cheers,

Justin.

swannies1983
05-12-2012, 11:23 PM
Thanks Justin. I've come along way with my processing....still have a lot to learn though.

Scorpius51
05-12-2012, 11:46 PM
That's rather impressive, Dan. Nice detail in there.

Cheers
John

ourkind
05-12-2012, 11:53 PM
That's awesome, very nice! It's reasuring to see that a DSLR can pull of such detailed images, thanks for sharing your work! :thumbsup:

jjjnettie
06-12-2012, 12:08 PM
beautifully processed Dan. :)

swannies1983
06-12-2012, 06:13 PM
Thanks for the comments everyone.



Yep, the humble dslr can produce some fantastic astro pictures. There's a yahoo group dedicated to dslr imaging and they compete well with CCD images. I have taken on board advice from Scott Rosen http://www.astronomersdoitinthedark.com/

ourkind
07-12-2012, 03:50 AM
Wow :eyepop: that's a great resource, I love the way he details how each image was taken. Bookmarked! Thank you :)

swannies1983
07-12-2012, 07:33 AM
Even better is that Scott has put up a long video (just over 2hrs) of his workflow of processing a M45 image. This is what I follow when I processed my Leo Triplet.
This is the link to his video

http://www.astronomersdoitinthedark.com/dslr_llrgb_tutorial.php

I particularly like the screen mask invert instructions which explains how to bring out the faint details without producing the noise.

You can also upload images to the Yahoo group and other members will have a crack at processing your images with most providing the steps.

troypiggo
07-12-2012, 08:20 AM
Lovely shot mate. Well done.

cfranks
07-12-2012, 09:03 AM
A lovely image and another fine example of how well PHD guides. The stars are really sharp.

Charles

hotspur
07-12-2012, 04:10 PM
Very nice image-well done on all your hard work.

Regulus
07-12-2012, 06:03 PM
Worth the hard work for that image. Well done.

swannies1983
07-12-2012, 08:12 PM
Cheers for the kind words :)

madbadgalaxyman
08-12-2012, 10:59 AM
Dan,

The scaling in your image is interesting, simply for the reason that it is not the "virtually standard" scaling that is often adopted to display galaxy images by amateur CCD imagers. As such, your image emphasizes features that are hard to see in other images..... for instance,the strong bar in M66 is much better seen than usual, and the semi-chaotic dust features in the outer parts of this galaxy are very well seen in your image.

All barred spiral galaxies are perturbed or asymmetrical, to a greater or lesser extent, for instance one strong arm and one weak arm is the normal thing in barred spiral galaxies. But the ability to see major structural features (rather than intricate details) in your image enables this astronomer to conclude that the level of dust asymmetry and the level of spiral-arm asymmetry in M66 are somewhat outside the normal range that is seen in those barred spiral galaxies that are not perturbed by another galaxy.
(I have done a lot of thinking over the years about the degree to which M66 is perturbed by other members of the triplet!!)

Also, I might add, relatively low angular resolution (such as in your shot) can actually be helpful in discerning large scale structural features in galaxies.
As an example, the overall dust lane in N3628 looks very chaotic in a high resolution image of it, so it is easier to see its overall structure in your image. (Sometimes, artificially degrading the resolution of a high-res image can actually reveal the overall shape of a feature much better!)

The galaxy M65 is actually a real puzzle, in terms of its overall morphology, as it is too close to edge-on to really get a clear idea of what it would look like if it were seen in a face-on orientation.
One serious and difficult question is: does M65 contain a bar structure that is seen in a highly foreshortened orientation?
What is particularly well emphasized in your image of M65 is a box or "X" structure in the central regions of this galaxy.....and this is often the signature of a bar that is seen in a relatively edge-on orientation.

Regards,
from Bad Galaxy Man

Ross G
08-12-2012, 10:33 PM
A great looking galaxy photo Dan.

Ross.

swannies1983
09-12-2012, 02:00 PM
Thanks Robert and Ross. Robert: I'm not going to pretend that I know what you are talking about but it all sounds really interesting. Thanks for the comments though.

madbadgalaxyman
09-12-2012, 04:49 PM
OK, Dan,
Sorry about the technical language in my post!!
So here is the deciphered/decoded/de-jargonized version of my post about the structure of M66 and M65 and N3628:

(1) M66 has one long spiral arm and one stub, which is not unusual for barred spiral galaxies, but the difference between the two principal spiral arms of M66 is greater than what we usually find in those barred spiral galaxies which are not influenced by gravity from nearby galaxies. Some spiral galaxies which are very strongly perturbed by nearby galaxies end up being virtually one armed galaxies, e.g. the LMC, NGC 2442, NGC 4027
{{ M66 had a previous gravitational interaction with NGC 3628, as can be shown by a bridge of cold (neutral atomic) gas that links M66 and NGC 3628 }}

(2) The dark nebulae in the outer parts of M66 are not distributed in a regular manner; the distribution of dark nebulae is somewhat abnormal in appearance. ( I have been just looking at the far ultraviolet (GALEX satellite) image of M66....and one of the two main spiral arms looks highly unusual!! )

(3) The overall heavy dust distribution within M66 makes it hard to clearly see the bar structure existing within this galaxy; but the existing long bar is easier to see at relatively low resolution and at the scaling adopted in your image of this galaxy.

(3) The "equatorial" dust lane in NGC 3628 looks split or bifurcated or tilted in high resolution images of it, but it looks relatively normal in your image of it. High-resolution imaging is not always more informative!!

(4) M65 may have a ring of Star Forming Regions (In other words: prominent nebulae, very luminous stars, etc.), within which a bar structure stretches from one side of the ring to the other side of the ring, but it is hard to see what is really going on in M65, because this galaxy is oriented (from our viewing point!) like a coin that is seen nearly edge-on.

cheers, Robert

Find out More about M66 at various wavelengths in my recent post in the science forum!!

Here is the Far ultraviolet plus near ultraviolet image of M65 from the Galex satellite. This is most instructive:

128040

The hot young stars of the spiral arms are clearly outlined in blue and white!!

David Fitz-Henr
11-12-2012, 09:02 AM
That's a terrific image Dan; you've brought out some great details! Good to see from a fellow Newtonian aficionado! That link looks like a great resource too - I'll have to go through those tutorials when I get a chance.

swannies1983
12-12-2012, 11:56 AM
Robert: Thanks again for taking the time to further explain your previous post.

Just out of curiosity, what do you mean by this:



What's the standard scaling?

In regards to the structures with the galaxies, I'm just happy I could make them out given what my subs were like. Also, my processing skills have come a long way but I still have a lot to learn. The differences you suggest from CCD images might be true or an artifact of my processing? Nevertheless, I appreciate the positive feedback because it means I'm on the right track :thumbsup:



Thanks David. The Newt is probably going to be put on ice for a while as I play with my new toy (RC8) :D

ew
05-01-2013, 07:54 PM
Very impressive and nice to know a DSLR can produce such a great image, your processing was worth the time spent it makes all the difference, I have a long way to go :thumbsup:

Jen
06-01-2013, 11:43 AM
Nice one Dan these are my fav galaxies to observe through my dobbie I just love how they all fit in the eyepieces together just nicely :)

swannies1983
06-01-2013, 05:47 PM
I appreciate the comments. Yes, processing is another ball game...which can be very frustrating at times :lol: