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8472

My first attempt at imaging - M31

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Doc

Dobs are never easy to image with so with the equipment you used I think it's turned out great. An itch well scratched I would say :D

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8472

Thanks Mick.

 

Something tells me my camera setup isn't optimal (not to mention my f5.9 ota and lack of neq6 as well!) . I think I maybe need to tinker with the iso and exposure length, maybe?

 

All the terrestrial amateur photographers I've spoken to tell me I need a lower iso level, but I'm not sure they're all too familiar with deep sky imaging. I think a bit more experimentation is on the cards.

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newtyng5

Hey that's pretty good Kev. Hope the guys (caretakers?) on the field didn't ruin any images (when they drove off pointing the car headlights at us). Look forward to next time.

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Graham

For a first attempt that is one to be proud of. 

You will be better off next time to knock the iso down to 800. This will produce less noise in your images. 

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8472

Thanks for the feedback guys.

 

I have just ordered a copy of "Making every photon count" so hopefully that will give me a better understanding of what's involved in all of this. 

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BAZ

I would be well chuffed with that as a first image and from a Dob it is impressive. Well done Kev. :thumbsup:

 

 

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Orion
For a first attempt that is one to be proud of. 
You will be better off next time to knock the iso down to 800. This will produce less noise in your images. 
Even 400 if the drive can manage it but suspect without guiding, it may not allow the longer exp without trails?

Sent from my GT-I9300 using Tapatalk

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Orion
Bought my 200p Dob, diy equatorial platform, a newly aquired dslr (an unmodded Canon 450d) and various other gubbins along to the Belper meet on 21/09/17, to attempt some rough and ready imaging.
 
I'm well aware these are far from the ideal tools for the job, but regardless, I had a major itch i needed to scratch!
 
First things first was to take some "flats" near the horizon before the sun set. As a photographic luddite  (photography is largely a mystery to me) I set iso to 1600 and exposure length to 6 seconds for the night (not sure my eq platform will permit subs >20 seconds).
 
Next was to polar align and level my platform and Dob. Then connect the dslr and focus setup with my diy Bahtinov mask.
 
Next came the "darks". All taken with the same settings as above, but with the scope cover on. 
 
My main subject of the night, was M31.
So all in all I took 40 flats, 40 darks and 189(?) lights. All at 6s exp, Iso 1600.
Thanks to the dew heater batteries in my telrad going flat, finding my subjects were trickier than they should have been. As a consequence, my other dso images (m51, m57 and m13) never materialized. Better learn to walk before I run, as they say.
 
So after some post processing with deep sky stacker (again with my prior experience of this stuff being virtually non-existent) i came up with this ropey effort.
 
Any opinions on how I can improve much appreciated!
 
20170922_130107_800x450.jpg.4e19c4882404b002efcb7140d6d99197.jpg
M31(2).TIF-800x533.jpg.86c62e2d34856af18d1a7ddd1825d401.jpg
Nice image. I admire your technical approach covering a lot of things. If you keep consistent like this, those great images will come running in. You'll get a great M42 for sure.

Sent from my GT-I9300 using Tapatalk

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8472

Thanks all again for the helpful tips.

 

I've recently invested in an Intervalometer for my dslr and just figured out how to utilise Live View on my lappy.

 

Far easier than trying to peer at my dslr's tiny display and viewfinder with my middle-aged eyes!

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Sunny Phil

For a first attempt, it's <expletive> good. I would tidy up a little bit after stacking using GIMP, like Photoshop only free.

 

You'll never get it quite right and you spend years getting that little bit closer.

 

I do a lot with a DSLR on its own.

On ‎01‎/‎10‎/‎2017 at 16:04, 8472 said:

Thanks all again for the helpful tips.

 

I've recently invested in an Intervalometer for my dslr and just figured out how to utilise Live View on my lappy.

 

Far easier than trying to peer at my dslr's tiny display and viewfinder with my middle-aged eyes!

Intervalometers are great.

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8472
12 hours ago, Sunny Phil said:

For a first attempt, it's <expletive> good. I would tidy up a little bit after stacking using GIMP, like Photoshop only free.

 

You'll never get it quite right and you spend years getting that little bit closer.

 

I do a lot with a DSLR on its own.

Intervalometers are great.

I've had a go with Gimp and a 7-day trial with Photoshop. To say the learning curve is steep for my feeble brain is an understatement! I don't suppose my colour blindness helps any, either. Gonna persevere with Gimp, though.

 

Fortunately having read my copy of "Making every photon count", there are some useful guides I can refer to.

 

I had no idea the post-processing stage was so involved and time consuming!

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philjay

Nice one. The 450d handles noise reasonably well but sticking to 800 max is will give you a good speed to noise ratio.

For an image of this depth with short subs darks and flats weren't really essential unless your sensor is very mucky and has a lot of dead / hot pixels and you suffer from vignetting but it's good practice for when you go for longer subs.

Try stretching the subs out to a minute if your platform can track for that long, you will really see the difference in the subs then.

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8472
1 hour ago, philjay said:

Nice one. The 450d handles noise reasonably well but sticking to 800 max is will give you a good speed to noise ratio.

For an image of this depth with short subs darks and flats weren't really essential unless your sensor is very mucky and has a lot of dead / hot pixels and you suffer from vignetting but it's good practice for when you go for longer subs.

Try stretching the subs out to a minute if your platform can track for that long, you will really see the difference in the subs then.

Welcome advice, philjay. I have since made the switch to iso 800, with a wide field milky way image I took a few days ago. No time to process it as yet but initial impressions point to less sensor noise.

 

I didn't know flats weren't a must have for short exposures. I'm only half way through an led light box build too! I may as well complete it, as I'm sure I'll find use.

 

I can confidently say 1 minute subs are somewhere between unlikely and never gonna happen with my current homebrew eq platform. I could be wrong, but i believe that is even beyond the (very expensive) commercially available dual axis units, if you can find one. They are really only meant for visual use and any rudimentary imaging is a bonus.

 

Cheers

 

Kev

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Bottletopburly

Worth trying startools for developing and it's free to try for as long as you want , I will be honest I don't get photoshop it's too involved for me personally,  I haven't the time it takes so startools for me simplified things and give me results I'm happy with , I will post links to it later , well done with your first go 👍

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8472

Wonderful, I'll delve into that when I get the opportunity.

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Sunny Phil
On ‎16‎/‎10‎/‎2017 at 08:39, 8472 said:

I've had a go with Gimp and a 7-day trial with Photoshop. To say the learning curve is steep for my feeble brain is an understatement! I don't suppose my colour blindness helps any, either. Gonna persevere with Gimp, though.

 

Fortunately having read my copy of "Making every photon count", there are some useful guides I can refer to.

 

I had no idea the post-processing stage was so involved and time consuming!

Yes, it can be. I've had some processing runs that have taken hours. I think Deep Sky Stacker gets really slow after about 50 images and I do really long stacks.

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