M13 - My First Ever DSO Image

[steve2310]

Hi all,

Well, after what seems an age of research and study I have finally managed to take my first DSO pic.

I am extremely new to SGL and astronomy and was "one of them" that discovered astronomy and astrophotography as a result of the "Stargazing Live" programs back in November.

Since then I have trawled the internet for various types of information regarding telescopes, DSLRS, mounts, eyepieces, guiding, software, processing etc etc!!!

I have spent hours reading this forum as the learning curve for astronomy and especially astrophotography is very very steep. But many thanks to those who have offered the time and advice the last few months.

Anyway, here is my first DSO - M13!! Prior to imaging M13 I had spent many nights collecting subs of M101 but just had to give up as I just couldn't seem to get it right (but that's another story!)

Serves me right for trying to image possibly the faintest object out there

This is image was taken with a modded Canon 550d, Equinox 120ed with flattener/reducer, CLS EOD Clip, NEQ6 Pro, LVI Smartguider @ approx 4 hours of 3 min subs, stacked in ImagesPlus, and processed in AP CS3.

I spent a long time trying not to overprocess the image but not sure I have been completely successful. I will attempt another process later in the week as I am still unsure as to the amount of colour displayed around the core and to be honest, I am still learning!!

To be honest I had real difficulty trying to balance the colour correctly but I think this might be to do with correctly setting the white balance when imaging the object. Not sure, but I believe I need to set a custom wb in the modded 550d?

Enough of the rambling - here's the pic. Please be gentle with me but any advice or thoughts would be really welcome!

Regards,

Steve

[Thelonious]

Very nice picture, congratulations. There also seems to be a galaxy at the bottom left corner of the picture. Looking to Stellarium I would think that is NGC 6207. Have you looked into it trying to identify it?

[steve2310]

Hi Thelonious

Thank you for the kind words - really appreciated. With regard to the galaxy I believe it is NGC 6207. Also, there seems to be another extremely small galaxy just above and to the right of NGC 6207 but not sure what that is?

Thanks again,

Steve

[Thelonious]

I think I know which one you mean. There seems to be another "puff" which suggests it's a galaxy although there might be even more of them if you really study the picture and find more of them. That'd suggest your picture has more to it than you thought! Unfortunately Stellarium doesn't show anything more in that area. But M13 is well-documented, perhaps someone more advanced in photographing it could identify that.

Edit: http://server5.wikisky.org/?img_source=IMG_904343:all&ra=16.717722&de=36.83278&zoom=8&show_box=1&box_ra=16.717722&box_de=36.83278&box_width=12&box_height=12&box_var_size=1

Have a look at this picture: M13 obviously in the center, NGC 6207 the blue-white at the top left and the bright red star lower is also there in your picture. Pointing the mouse left oft the NGC 6207 shows some other objects, maybe the other galaxy is somewhere identified in this Wikisky picture.

[Revs]

Wow Steve, that's pretty bloomin' good! Great detail, exposure, framing, everything. If I had to knit-pick I'd say the colour balance might be slightly off, but that is knit-picking.

Superb!

[steve2310]

Thanks Paul

I have to say I was a little anxious posting the image as it was my first and having seen so many fantastic images on this site I was a bit apprehensive.

You are right re: the colour balance. I have tried to balance the image using a Macbeth colour checker but I seem to battling (I think) with the camera being modded and the CLS Clip. When I first tried to balance the colours in AP the green of the RGB was the highest and so I balanced the red and blue to this. However, having done this, I checked the colours using the colour sampler tool and the darker the colour the weaker the green figure became - I hope that makes sense?

I'm not sure where I went wrong but I think it is to do with setting the WB in the camera when I take the picture. I believe I need to set a custom WB in the 550d as it is modded but I'm sure the more experienced guys can put me right or show me the way with this?

It seems strange though that the green channel was the strongest when the camera is modded.........something else to learn and overcome!!

Steve

[Revs]

Not sure about this, but I suspect you could use an EL panel for WB as well as for flats. Maybe someone could confirm..?

[Adamski]

looks very good to me. i gotta get me a dslr.

[Cloudwatcher]

I must agree with others,a most excellent first image.

Re the colour balance aspect,each individual will see colour in a different way............ for instance I see the image as having a magenta cast......... a quick play with the Hue/Saturation controls in CS3 will change the colours to individual taste...... I would see it like this....... others differently but whatever the colour it is still an excellent image!

P.S. Lets have a look at your M101 image.

[steve2310]

Thanks CW for your input as well as your kind words. I have looked at several images of M13 and as you have stated, have seen several very different 'colour' versions!

I am going to have a second attempt at re-processing again later in the week in an attempt to capture the "natural" colour as best as I can (but we'll see!!)

Thanks again,

Steve

[26Left]

Steve,

Your research has paid off, because this is a terrific image. M13 is one of my favourites. It's difficult to show the fainter outer area without blowing out the centre. But, you've done it!

The colours are easy to correct. The important thing is that different stars are different colours rather than being burned out. So, you've still got information in the image to play with.

The other faint fuzzy is the galaxy IC4617.

Cheers,

Tom.

[steve2310]

Thanks Tom really appreciated, and thanks for solving the other galaxy "question".

I'm going to go back and have a "play" with the colours in the next few days as well as having an attempt with the tools in ImagesPlus for processing (as they are actually looking pretty useful).

Thanks again Tom,

Steve

[steve2310]

Cloudwatcher: Sorry meant to say - I'll have a go at processing the M101 data when I get a chance so you can a look but it's not great - such a tough object!

[ollypenrice]

So we have

-round stars

-smooth sky without gradients

-good focus

-significant depth

... all on the first night out! Hearty congratulations.

I, too, think the colour was out towards the magenta but processing can deal with that. I like Cloudwatcher's tweak. PixInsight has good routines for colour balance and artefact elimination in astro images.

You're a marked man. We expect nothing but the best!

Olly

[steve2310]

Thanks Olly but believe me it took A LOT to get me to that point (i.e, many nights of trial and error and countless hours watching video tutorials on the net and I now have a well thumbed copy of Steve's book!) and hey, I still didnt get it quite right.

However, that's what I love about this new hobby - the constant learning and tinkering!

With regard to being a marked man, well, if I'd have shown you guys the M101 you wouldn't be so impressed. I'll try and process it over the next few days and you can see my reasoning!

Thanks again though.

Steve

[steve2310]

For those guys that were interested in my failed M101 well here is a rough process of it. It's a little pink for some reason and have quickly tried to overcome this but again I'm still learning.........

I obviously didnt have enough matching darks hence the noise but this was part of my learning curve etc. It's a mixture of ISO's, 800 and 1600 and the majoirty of subs were 6 minutes but the noise comes from 10 x 15 min subs that I failed to get darks for.

To be honest I found M101 just too tough for a first object to image and I was a lot happier once I decided to have a go at M13.

Not sure what to have a go at next but the North American Nebula region is appealing.....especially as I have just bought a WO Megrez 72 APO. Happy days.

Any help with how to go about imaging the 101 for next time would be great.

Cheers guys,

Steve

[26Left]

I use a Nikon DSLR, so I cannot comment on your camera. But, on mine, 15 minute subs are out of the question. There's just too much noise. I generally take 3-5 minute subs, although I have pushed it to 8 minutes with some success, but I get better results by bringing the exposure time down to 4 minutes and doubling the ISO. As I say, Canon may be different.

The problem with long exposure times on a DSLR is that the sensor gets hot and generates more noise. A good tip I read is to leave a gap between exposures to allow the sensor to cool down. So, If I take a 4 minute sub, I wait a minute before taking the next one.

How about M27, the Dumbell Nebula as your next target?

Tom.

[steve2310]

Tom: The 15 min subs were more of an experiment really, plus, it certainly brought out the finer detail of the spiral arms of M101. The noise of course is a lot worse at this length of time and even more so as I had no matching darks to subtract.

The M13 image above is made up of 3 minute subs and I left about 1m30secs inbetween to let the chip cool etc. and having match darks meant the final image is quite smooth.

I'm just off to check out M27...sounds very interesting!

[shaunster]

failed M101? thats an great M101....

[Cloudwatcher]

I think your too modest,that's a good capture............ whats not to like?

[Coco]

Crikey, I've got my eye on your posts...

[steve2310]

Cheers guys but I'm still not happy with it. I'm actually spending the afternoon stacking the pictures WITHOUT the 15 min subs and see what I can get from 76 6 min images. I'll see how much of a difference this makes? Will post the result later.

[steve2310]

Ok, not sure if this is coming off subject now re: M13, but here is M101 minus the 15 min subs causing all the noise. However, having removed them there is less finer detail - smoother though.

[26Left]

Still plenty of detail. I think it's a great image.

[stolenfeather]

Amazing capture. You surely put those hours of research into good use! Yes, you did seem to have also cornered a galaxy on the far left! Congratulations!

Isabelle