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First DSO, M31 with bad color balance


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Great first attempt :) I think you may be able to extract more data from that in the post processing. The background has a slight magenta cast which you could correct. There's a lot to learn in this pasttime.

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Thanks for your kind words. Needless to say I am extremely pleased with the initial result and I'm very eager to really spend some time on it, and I've been looking at some processing tutorials I'll try and bite down on when I get home. My raw's were taken with the tungsten blueish white balance out of habit, but I think that DSS can neutralize the temperature in raw. Also the first result was a Lovecraftian greenish hue, but I probably overcompensated by a mile ;).

Oh, about 15 minutes of data was usd, divided in 20 second subs @ ISO 3200, 12 darks.

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Good effort .. I just imported the higher res image into photoshop and did an auto colour and immediately got a more natural look.. then use image-adjustments-colour balance for better results..

There is loads of data here un stretched..

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Amazing how much of M31 you've captured with only 20s subs, great job! Flats will help a lot with the processing.

In-camera white balance settings are ignored unless you tell DSS to apply them in the "RAW Settings"

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Thanks. Had another go at it. I really have no idea how long I could try to coax out information that might not be there. But after reading on the forums, I don't think I should overwork myself with 20 second subs. Anyway, I think this version is a bit more delicate. Maybe I overdid the color in the stars, but I like it better this way. Feels like I have a lot to do in the future like enhancing the capacity of my setup, take more and longer subs and learn how to work them. What fun would a hobby be if you mastered it right away? ;)

Reprocessed first DSO M31

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Hi Carl,

That is brilliant, much clearer than my first attempt. I used 120 seconds at ISO800 , but over exposed. Translating from your pic 20 secs at ISO 3200, I suppose I should have used 80 seconds.

Did you use a filter?

I am guessing you didn't use a guidscope?

One last question, how dark are your skies?

Thanks

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Robin, there is no filter, just a 6" newt and my unmodded DSLR. Unguided. That's the reason for the short exposures, I could probably have gone up to atleast 30sec or more, but I settled for 20, just to see what was doable.

The conditions for the night were good, but the skies arent really dark, if you look at this map, find the yellow zone between Uppsala and Stockholm labeled Märsta, thats roughly where I took my pictures:

http://www.aquilastronomy.com/images/vlmag_central_sweden.jpg

Luckily I have two good sites about 1 hour of driving thats situated on the edge between cyan and light blue areas. I guess that's where I'm heading when I want to get real serious.

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Hey that is great Carl, I can see you getting some great pictures. My first attempt was was 80 sec unguided, just tracked on an eq6. In about an hour and a half M31 hardly moved so guiding wouldn't have made too much difference.

Unless the object is in a fast moving part of the sky, unguided I find that at 60 secs you throw away about 10%, at 90 secs about 20% and at 120 secs around 30-40% of the frames get thrown away. Of course it helps if it is not windy.

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Thanks, its good to know. I'm getting a cheap timer remote for my Nikon soon, then I'll try some longer shots than 30secs, can't be bothered with manual timing at this point, since I'm just learning the basics.

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