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Luna-tic

M13 last night

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Okay, the setup: I stayed out all night last night, set up the Edge 8 just before dark and viewed for a couple of hours before the Moon could come over the trees and fully wash out my sky, which was absolutely cloudless, with the best seeing since......probably last Spring. Unfortunately, the Full Moon rose about 8pm, so it wasn't a dark sky. I just looked at thing toward the north and west as much as possible. I took a break about 10pm, went in to get a cup of coffee, and Blade Runner-Director's Cut  was just starting, so I had to get my sci-fi fix for the day. Went back out about 1:30am, the Moon was high by then and you could easily read a book by the light. Undeterred, I restarted my scope (AVX, used "last alignment" and it was dead-on). I was limiting myself to stars, looked at a bunch of doubles, and then I thought....clusters. M13 being rather far removed from where the Moon was, I skewed over to it and, expectedly, saw a dim blob, which would have been much better in a dark sky. So, I wondered if taking a picture would work. I had a 13mm Ultima Duo eyepiece in, it's threaded for a T-ring, so I attached my D3400, set it to bulb and ISO 6400, and commenced shooting some EPP, starting at 10 seconds and working up to 30 seconds at 5 second intervals. I had to shoot quite a few, checking focus and adjusting as I went, but finally got something you could identify. I looked at M42 for quite a while, managed to split Rigel, looked for a while at Alnitak. I considered looking for "attack ships burning off the shoulder of Orion" (movie quote from replicant Roy Batty). I saved my eyes for the last, looked at the Moon, unfiltered, then broke everything down and went inside about 4:30 am.

Nothing fabulous, but for a bright night and early AP effort, I'm happy with the outcome. This is a single-exposure at 27.5 seconds, ISO 6400.

M13 Hercules Cluster 10-17.JPG

Edited by Luna-tic
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Sounds like you had a very rewarding night of astro... great stuff.... 

Not a bad single frame... Imagine how good the stacked version of the single sub would be if you stacked 20 or 30 of them, stretched the curves and ran a slight unsharp mask through it.

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35 minutes ago, MarsG76 said:

 

Not a bad single frame... Imagine how good the stacked version of the single sub would be if you stacked 20 or 30 of them, stretched the curves and ran a slight unsharp mask through it.

Yeah, I looked M13 up on Wikipedia and they have a picture of the cluster made through a C8, most likely as you describe. I can only hope that one day.......

 

I don't figure to get really good shots for a while, I haven't downloaded any stacking software yet, and it will be a while until I get really serious. For now, just some quickies to see what I'm up against, since the prevailing winds on the forums say that learning AP with a SCT is  doing it the hard way. So far, it's not much different from learning basic photography skills. It's all about exposure and steadiness and patience.

I found last night that after 30 seconds exposure, the background light became an issue, as the image began to resolve more, the entire frame started washing out. I'm sure a very dark sky would have given me at least a minute or two before the noise overwhelmed the rest of the image. I tried shooting longer at a lower ISO (3200), but the results were much the same. Just can't do DSO's when the Moon is full.

Edited by Luna-tic

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25 minutes ago, Luna-tic said:

Yeah, I looked M13 up on Wikipedia and they have a picture of the cluster made through a C8, most likely as you describe. I can only hope that one day.......

 

I don't figure to get really good shots for a while, I haven't downloaded any stacking software yet, and it will be a while until I get really serious. For now, just some quickies to see what I'm up against, since the prevailing winds on the forums say that learning AP with a SCT is  doing it the hard way. So far, it's not much different from learning basic photography skills. It's all about exposure and steadiness and patience.

I found last night that after 30 seconds exposure, the background light became an issue, as the image began to resolve more, the entire frame started washing out. I'm sure a very dark sky would have given me at least a minute or two before the noise overwhelmed the rest of the image. I tried shooting longer at a lower ISO (3200), but the results were much the same. Just can't do DSO's when the Moon is full.

You'll get there, even exceed what is displayed on wikipedia, but like you said.. it is a learning curve. Once you start imaging using your SCT, it's not that bad or hard... really you will only be limited by the sky condition at such a high focal length. 

Imaging anything other than planets and the moon during a full, or near full moon will be difficult, no matter what scope you use, unless you use a HAlpha/SII narrowband and a bit of distance from the moon. I did image the horsehead nebula during a nearly full moon and it turned out OK, but Narrowband imaging is not something I would recommend until you have long exposure, guiding etc sorted out, first either grey scale or RGB/OSC.

Even a lot of 30 second exposures on a lot of objects stacked renders amazing results. Don't worry too much about pushing the ISO up very high, when you stack 20, 30 or 40 30 sec exposures, the noise will be all but canceled out. try it (on, for example, the Orion Nebula M42), you will be surprised.

You'll get there, just keep practicing and do not give up.

Good luck

 

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Good job. Sounds like a rewarding night, even under the light of a silvery full Harvest moon! I've taken some shots of M13 in the past and stacked up to 6-30-second subs at 1600 ISO (my camera's limit at the time) in DSS to get results like this:

gallery_39922_3892_771190.jpg

I'm not deep into imaging but like to have fun capturing a few shots here and there. It's ok if it's not Hubble, lol!

Reggie

 

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20 hours ago, MarsG76 said:

 Once you start imaging using your SCT, it's not that bad or hard... really you will only be limited by the sky condition at such a high focal length. 

 

 

With the f/7 reducer, imaging with it won't be much different than many refractors. I've also got the option of Fastar (financially down the road a piece) that will allow me to image at f/2.  But I'll certainly take a dark sky any time I can find one.

19 hours ago, orion25 said:

Good job. Sounds like a rewarding night, even under the light of a silvery full Harvest moon! I've taken some shots of M13 in the past and stacked up to 6-30-second subs at 1600 ISO (my camera's limit at the time) in DSS to get results like this:

gallery_39922_3892_771190.jpg

I'm not deep into imaging but like to have fun capturing a few shots here and there. It's ok if it's not Hubble, lol!

Reggie

 

I like that. Nice, dark background, which I realize stacking allows, since you can better control and eliminate noise.

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