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My first M51


Shiinsuh

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I've only got into astrophotography in the past month or so. This is my first real deep sky object I have photographed. I had taken 8, 4 minute exposures at ISO 800 plus 2 darks.
Let me know what you guys think and any tips for post processing and for further photographs.

post-36381-0-70850300-1397862535_thumb.j
M51 Whirlpool Galaxy.

Taken with an unmodified canon T3i, through a Celestron c130 Mak on a CG-5 GT mount.

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Better than any of my m51's

I'm sure that's not true.

well done on the first capture,

can`t say i`ve ever seen an orange glow in the image before, is there alot of light pollution in your area, if so a good anti light pollution filter should help.

I live in a suburb so there is a bit of light pollution. The problem is that my camera mount does not have a filter thread, else I would have used a light pollution filter.

It could however be to do with the settings on my camera.

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Nice capture, thank you for sharing it with us.

I was looking for this one the other night but couldn't find it anywhere, even tried down the back of the sofa...

Thank you.

I could not actually see this with the naked eye through the telescope. I just set the Goto up and hoped for the best that it was on target, then did a 30 second exposure to see if it was there. Luckily it was.

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I'm just thinking, your polar alignment is off as your stars have trailed. And it is better than mine. Galaxies aren't my imaging cup of tea. Clusters and planetaries are my area

Yeah, I didn't spend much time aligning maybe 30 seconds or so. I was only intending to do some 'browsing' of the sky. But thought id give this ago.

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That's  a very nice first attempt! :)

You seem to either have tracking issues, or very poor seeing conditions. Therefor your stars have a distorted shape.

Your color balance is off, that's why your image is so orange. The color channels can easily be aligned when stacking is completed in for example deep sky stacker.

I'm guessing you have some street lights causing this, as well as washing out the sky a bit.

There still is data in there though. And with a quick go in photoshop, correct the colors a thiny bit, and adjusting teh curves and levels a bit for teh contrast, it looks like this.

Hope you don't mind? :)

post-9520-0-90883900-1397867297_thumb.jp

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That's  a very nice first attempt! :)

You seem to either have tracking issues, or very poor seeing conditions. Therefor your stars have a distorted shape.

Your color balance is off, that's why your image is so orange. The color channels can easily be aligned when stacking is completed in for example deep sky stacker.

I'm guessing you have some street lights causing this, as well as washing out the sky a bit.

There still is data in there though. And with a quick go in photoshop, correct the colors a thiny bit, and adjusting teh curves and levels a bit for teh contrast, it looks like this.

Hope you don't mind? :)

Oh wow. I obviously have a lot to learn if you can get this out of the fuzzy orange hue photo. 

I did not actually use DSS, I Stacked the pictures manually in photoshop as there was only 10. DSS may have done a better job or not but I have not learnt how to use it correctly yet.

As you suggest tho, I do have tracking issue as i only spent a short while set. I do also have a lot of street lights about (this was done in my back garden)

I will have a further play about with the image see if i can get more detail out of it.

But thank you for showing what I can get from such an image.

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I recommend to give DSS a try. Basically, the standard settings are ok.

What you shuold adjust is this:

Star detection treshold: adjust until about 20-200 stars are detected. If you're using shourt exposures, use median filter when detecting.

Stacking method: I usually use average when i have less then 10 images. Anything higher then this, and i use cappa sigma-clipping.

when stacking is complete: drag the middle slider on each color until they're aligned and the image looks OK illuminated (as in light gray background, NOT black). Set the saturation slider to +16 to +20. I usually use +18, and do final adjustments later.

That's mainly all you need to know to get started with DSS as far as i remember. :)

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it can be a very difficult little thing to find, if you have goto and not a polar aligned very well then i slew to the last star in the polough handle, sync the scope finder on that to aglin it then it`s just a little hop to M51 from there.

also i find when using dss, that the autosave image sometimes comes out better than the actual one you save, so have a play with both versions in photoshop, the autosave version is usually saved in the folder where you get your light frames from.

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I recommend to give DSS a try. Basically, the standard settings are ok.

What you shuold adjust is this:

Star detection treshold: adjust until about 20-200 stars are detected. If you're using shourt exposures, use median filter when detecting.

Stacking method: I usually use average when i have less then 10 images. Anything higher then this, and i use cappa sigma-clipping.

when stacking is complete: drag the middle slider on each color until they're aligned and the image looks OK illuminated (as in light gray background, NOT black). Set the saturation slider to +16 to +20. I usually use +18, and do final adjustments later.

That's mainly all you need to know to get started with DSS as far as i remember. :)

I have had a little go with DSS but with this image it will only use one of the 8 photos I had taken. I don't know how to make it use all 8 or at least a few more. This has been my problem i've had in the past using the program. I still need to learn how to use it But thank you for the settings I will give them a try once I figure it out.

Nice capture, I like it as its what a beginner sees, I have spent 3 nights trying to see it, managed a faint sighting of it earlier. waiting till the viewing is better without that moon annoying me.

Thank you. I guess I got lucky on finding it.

it can be a very difficult little thing to find, if you have goto and not a polar aligned very well then i slew to the last star in the polough handle, sync the scope finder on that to aglin it then it`s just a little hop to M51 from there.

also i find when using dss, that the autosave image sometimes comes out better than the actual one you save, so have a play with both versions in photoshop, the autosave version is usually saved in the folder where you get your light frames from.

My polar alignment was out but I used a lot of calibration stars to tune the goto as best I could. I will also keep in mind what you said about DSS :)

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You either have too distorted stars for dss to detect (it's very picky, and expect stars to be only a few pixels accross) - or you have set the star detection treshold % too low so it detect noise as stars. Its one of those two, 99.9% sure. :-)
If you upload a single feame and we can tell you whats wrong and/or what settings to adjust in DSS.

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Thank you.

I could not actually see this with the naked eye through the telescope. I just set the Goto up and hoped for the best that it was on target, then did a 30 second exposure to see if it was there. Luckily it was.

great start! now do 100 30sec subs and see the difference, and maybe try a different white balance that may be down to the orange glow and/or LP

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You either have too distorted stars for dss to detecy - or youve set star detect treshold % too low so it detect noise as stars. Its one of those two, 99.9% sure. :-)

upload a single feame and we can tell you whats wrong and/or what settings to adjust

Here are 4 of the photos:

http://i.minus.com/ib2qMVEQSkxr3x.JPG

http://i.minus.com/iKeMOhqTf9qs4.JPG

http://i.minus.com/iQjz6PZkOxx4O.JPG

http://i.minus.com/ibi4SJ67PSXKPp.JPG

Obviously the pictures aren't the best due to the tracking being off.

I set DSS to detect around 25 stars although each photo only has about 15 so maybe I should increase it further? 

great start! now do 100 30sec subs and see the difference, and maybe try a different white balance that may be down to the orange glow and/or LP

I will try changing the white balance, see what that gives me. And on the next clear night I think I will have to spend longer setting up the mount and give a try of a lot of shots and see what happens :).

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That's  a very nice first attempt! :)

You seem to either have tracking issues, or very poor seeing conditions. Therefor your stars have a distorted shape.

Your color balance is off, that's why your image is so orange. The color channels can easily be aligned when stacking is completed in for example deep sky stacker.

I'm guessing you have some street lights causing this, as well as washing out the sky a bit.

There still is data in there though. And with a quick go in photoshop, correct the colors a thiny bit, and adjusting teh curves and levels a bit for teh contrast, it looks like this.

Hope you don't mind? :)

By the way. Could you give me some details on the processing you did on this image. I have played about a bit and got some blue out of it but nowhere near as much as you have. I'm just wondering what exactly you have done.

This is what i came up with.

inkXtBDdNv6IT.jpg

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Here are 4 of the photos:

I set DSS to detect around 25 stars although each photo only has about 15 so maybe I should increase it further? 

I'm sorry to dissapoint you here, but there's no way DSS is going to be able to stack your images.

Your stars are not just "distorted" to some level, but actually more like small lines, so DSS will never detect them as stars. What DSS detects as stars in your images are not the stars, but random noise. As random noise is never in the same spot in two frames, DSS can't align the frames and will only stack one out of *insert whatever number here* frames.

Manual stacking is probably the only way in this case.

If i were you, i'd practice on polar aligning. It's critical to get this quite spot on when you don't have a guide system to compensate for it.

First polar align as well as you can, then star align as well as you can. Then go to a star close to the target you want to image, and see how long exposure you can get befor stars are no longer pinpoint. When you've found maximum exposure time (i'd say the absolute limit is when the stars are twice as long as wide), adjust the ISO so the histogram "starts" about 1/4 to 1/3 of the wat from the left.

Like this you're sure that DSS will stack your frames, and you'll get a much more clear picture. It's much better to have 60x 1min exposures with pinpoint stars then 15x 4min exposures where the stars are lines instead of pinpont - even though both of these two are 1 hour total exposure. :)

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I'm sorry to dissapoint you here, but there's no way DSS is going to be able to stack your images.

Your stars are not just "distorted" to some level, but actually more like small lines, so DSS will never detect them as stars. What DSS detects as stars in your images are not the stars, but random noise. As random noise is never in the same spot in two frames, DSS can't align the frames and will only stack one out of *insert whatever number here* frames.

Manual stacking is probably the only way in this case.

If i were you, i'd practice on polar aligning. It's critical to get this quite spot on when you don't have a guide system to compensate for it.

First polar align as well as you can, then star align as well as you can. Then go to a star close to the target you want to image, and see how long exposure you can get befor stars are no longer pinpoint. When you've found maximum exposure time (i'd say the absolute limit is when the stars are twice as long as wide), adjust the ISO so the histogram "starts" about 1/4 to 1/3 of the wat from the left.

Like this you're sure that DSS will stack your frames, and you'll get a much more clear picture. It's much better to have 60x 1min exposures with pinpoint stars then 15x 4min exposures where the stars are lines instead of pinpont - even though both of these two are 1 hour total exposure. :)

I can fully understand that DSS would not like my images due to just being blurry lines. I have only recently started with astrophotography, so i haven't polar aligned before now. So its something i need to practice doing some more. 

But next time I am out I will try more, shorter exposures along with spending more time aligning and I'll see how that goes.

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I can fully understand that DSS would not like my images due to just being blurry lines. I have only recently started with astrophotography, so i haven't polar aligned before now. So its something i need to practice doing some more.

But next time I am out I will try more, shorter exposures along with spending more time aligning and I'll see how that goes.

Don't worry,I'm just staring out as well,funny thing I did m51 last night,20 subs but dss won't stack them,just got to get better at polar aligning

Ciro

Sent from my iPhone using Tapatalk

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Its great to see these first images I remember my first shots of m51 you will soon learn how to improve on things like focus processing and polar alignment, take a look at my blog just search for m51 you will find several attempts in there the main thing is to enjoy doing it nothing beats the thrill of doing these thing for the first time though.

Sent from my Nexus 7 using Tapatalk

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