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My First Ever Galaxy Images/Awful!


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1 hour ago, Clarkey said:

Well done - that looks much better. At the end of the day, the data capture is the 'easy' bit - the processing is the thing that takes time to master. I am only 3 years into my AP journey, and I still consider myself a novice when compared to many others.  With longer integration times there is no reason why you shouldn't get some excellent results. Keep it up!

@Clarkey Thanks mate. Yes the processing part is definitely much more difficult than the acquisition, which itself is pretty darn difficult in the beginning! LOL.

Yes next time, because I only used my small 66mm aperture 400mm FL refractor to image the Leo Triplet, next time I'm going to use my big 200mm Aperture 1000mm FL Newt. Reflector, which actually has a faster FR than the little refractor, F5 compared to the small ones F6, respectively. So with the much larger aperture, more than double FL and faster optics, I'm hoping to get much more zoomed in, much better resolution and faster optics, and I'm also I'm aiming for double the total exposure time, so I should manage a really good image of it. Can't wait! 

Thanks again! Wes.

Edited by wesdon1
spelling mistake! I hate them! LOL
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@wesdon1 I still haven't gone down the rabbit hole of photography yet but I certainly would like to. If I could get photos like that I would be very happy. They look great to me! 

And I love the work the gang here have done on the images too. Great stuff!

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On 27/03/2023 at 09:16, alacant said:

Any type of dark frame on an eos is bad news.

I'd be delighted to help you out with more contributions if necessary.

I'm interested to know why you say any type of darks are bad news on an eos? Up to now they have been a regular part of my routune

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Well done Wesdon, I am glad our advice helped, and you'll go on to bigger and better things.  Guiding will make a heap of difference if you can get to that stage.  

As some-ne humerously said before some of us did far worse images when we started out, I'd be ashamed to show any of mine, or even if I still have them lol.

Carole 

Edited by carastro
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2 hours ago, Sarek said:

bad news

Hi

If it's working for you, stay with it.

The Digic circuitry introduces artefacts which makes it more difficult to process, especially the background. Link that with the impossibility of producing temperature matched darks to introduce yet more noise and well...

If all that's needed is to lose the offset, then yeah... I'm all for keeping it simple.

Cheers and HTH.

 

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3 hours ago, carastro said:

Well done Wesdon, I am glad our advice helped, and you'll go on to bigger and better things.  Guiding will make a heap of difference if you can get to that stage.  

As some-ne humerously said before some of us did far worse images when we started out, I'd be ashamed to show any of mine, or even if I still have them lol.

Carole 

Aww thanks @carastro. As I said, I was/am eternally grateful for your and others advice/help. 😊

yes funny you should ask about guiding because that’s now my next target ( no pun intended! ) I received the adapter I need to fit my ASI 120MM to my SW 50mm Finder yesterday, and I already own a good Laptop, so I’m going to start learning to do multiple minute guided subs as soon as weather permits. 

LOL I should have qualified my title “My First Ever Galaxy Image” because although it’s my first Galaxy image, it’s not my first Astrophotography image! I’ve done about 7-8 DSO’s so far, and a couple of planetary, so I hope my title didn’t come across as dishonest!? 🤦‍♂️😂 But yes it was/is my very first ever Galaxy attempt! 

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7 hours ago, Bogmonster said:

@wesdon1 I still haven't gone down the rabbit hole of photography yet but I certainly would like to. If I could get photos like that I would be very happy. They look great to me! 

And I love the work the gang here have done on the images too. Great stuff!

@Bogmonster please don’t let my dramatics put you off though mate! 😂 Aside from some very stressful problems along the way ( I’m about 4 months into Astrophotography ) this new hobby has been an incredible experience and the highs far far outweigh the lows! So I’d say have a go when you’re ready, and just try keep it super simple and basic in the beginning. Don’t get carried away wanting all kinds of special cameras, mounts etc, like I did. Just use a cheap second hand DSLR camera, and just start taking pictures and see where it takes you. It’s an incredibly rewarding experience. Best of luck, and obviously if I can help in any way, let me know. I’m a new guy still, but I have learned a lot so far, so I can be helpful for beginners. 👍

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On 30/03/2023 at 17:53, wesdon1 said:

@Bogmonster please don’t let my dramatics put you off though mate! 😂 Aside from some very stressful problems along the way ( I’m about 4 months into Astrophotography ) this new hobby has been an incredible experience and the highs far far outweigh the lows! So I’d say have a go when you’re ready, and just try keep it super simple and basic in the beginning. Don’t get carried away wanting all kinds of special cameras, mounts etc, like I did. Just use a cheap second hand DSLR camera, and just start taking pictures and see where it takes you. It’s an incredibly rewarding experience. Best of luck, and obviously if I can help in any way, let me know. I’m a new guy still, but I have learned a lot so far, so I can be helpful for beginners. 👍

Thank you! I may be back to you on that. I'll be starting out with the moon and planets before I get into the DSO stuff. Just figuring my way around right now and getting used to my scope. The only pictures I have right now are from my phone using one of them adapters.

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@Bogmonster Oh definitely, just start out with big bright targets like the Moon and brighter planets such as Jupiter, Saturn, Mars ( Jupiter and Saturn aren't currently available, but in a couple of months they'll start being available in the early morning skies, and then as time passes they'll rise at more favourable hours i.e. night time after sunset and so on. And yes I think you'd be wise to keep just learning your way with visual astronomy, and with time you'll be much better prepared for imaging. The Moon is an incredibly rewarding object to image, and best of all, it can be as simple as "point and shoot" and you're pretty much finished! There's no need for long exposures, or recording videos of it and then processing the video frames etc. 

Thank You again for such kind words! I'm here if you ever need any help! 

Clear Skies!

Wes.

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On 27/03/2023 at 03:16, alacant said:

Any type of dark frame on an eos is bad news.

But aren't they required for the math for flats? Or are you saying that bias is OK and darks/dark-flats don't work? Not an EOS guy, so I am asking for info, NOT arguing.

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57 minutes ago, rickwayne said:

aren't they required for the math

In the real world, perhaps best to lose the theory. Hands on tells us to simply remove the offset.

57 minutes ago, rickwayne said:

darks/dark-flats don't work

For DSLRs, no. One of the main reasons is the impossibility of temperature matching.

Cheers and HTH

 

 

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2 hours ago, rickwayne said:

But aren't they required for the math for flats? Or are you saying that bias is OK and darks/dark-flats don't work? Not an EOS guy, so I am asking for info, NOT arguing.

With most modern DSLR models - firmware does "internal" dark subtraction.

Each row of pixels on sensor has first 16-20 pixels masked. Those pixels are also exposed with main exposure but they are effectively in "dark" mode as they are masked and don't get any light.

Firmware then takes average value for each row (for some reason due to manufacturing process - rows have similar level of dark current and it is best treated per row) - and then subtracts that from the rest of the row.

It is not ideal dark calibration - but works good enough and makes regular dark calibration redundant (it won't cause issues but will add noise back in the image which you don't want). In fact - given that one does not have control of temperature - this is actually better solution. Masked pixels are at the same ambient temperature as the rest - and internal dark subtraction is not temperature sensitive as normal dark calibration is with DSLR.

For sensors that have distinct bias pattern in the image - I'd recommend to remove bias manually (in fact - I'd do that for any sensor) - but you can get away with using numeric offset value - usually 2048 ADU or 1024 ADU depending on sensor and its ADC.

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