Wide Field Orion (plus possible dust on camera sensor?)

[Adam1234]

I decided to take a wide(-ish)field shot of the area around Orions Belt the other night using my Canon 2000D at f/5.6 and ISO-800 using the stock 18-55mm lens at 55mm. I took 35 subs at 60s each and stacked in DSS. I'm quite happy with the result, I can clearly see the Great Orion Nebula and if you zoom in a bit can also see NGCs 1973/1975/1977 just above Orion Nebula. If you look close, it looks like I've also captured a tiny bit of light from the Flame Nebula NGC 2024 by Alnitak.

The only things I'm not happy about in this image:

•  These black blobs that have been appearing in my images lately, I think these are probably bits of dust on my sensor. Any idea how to check if is indeed dust on the sensor and how I can clean it, or should I take the camera into the shop and get a professional to do it? In the meantime, is there any trick I can do in photoshop to hide/remove these from an otherwise nice image? 
•  Stars aren't perfect if you zoom in. Probably due to focusing (really difficult with getting good focus when using the camera lens pointed at a dark sky!) and less than optimal tracking/polar alignment. But not bad if you don't zoom in though, if you ignore the dark blobs caused by the dust!

 

Thanks for looking.

Edited March 4, 2020 by Adam1234

[celestron8g8]

Looks like dust bunnies to me . Try a little hand dust blower to blow off sensor or mirror and see if those still show up . 
 

 

[geeklee]

Nice image Adam with good framing of Orion too.  You're right, you can definitely recognise the flame nebula by Alnitak.

Anything in my imaging train usually gets a treatment from a "Giottos GTAA1900 Rocket Air Blower" before going together.  I've found this brilliant for clearing unwanted dust and light debris.  Not sure if that could still work on a DSLR body and lens (with care!)

I've found focus with a DSLR (by itself) very tedious as you mention.  Live view helps but I've found continually taking shots as you go up to infinity focus, inspect on camera for best star shape then work back slightly until you're happy.  Not exactly a bullet proof approach, sorry!.

[TerryMcK]

Normally get rid of dust bunnies by taking flats and putting them in the stacking software. You can clean the sensor yourself with a blower brush or better still a can of compressed air specifically for cleaning photographic equipment. Set the camera to bulb mode, remove the lens and depress the shutter release. The shutter blades will open. While holding the release button down carefully spray the air onto the sensor. Try to hold the front of the camera oriented down so any dust or hairs fall by gravity away from the sensor.

Let go of the shutter release, spray once again to clear the cavity and it should be good. Repeat if you can still see dust in the sensor. It takes only a few minutes to carefully do this yourself.

[discardedastro]

Flats are definitely the correct answer for dust. This calculator can help you find which surface the dust is on, too: http://www.wilmslowastro.com/software/formulae.htm#Dust

[Adam1234]

Thanks, I'll have a look for some compressed air and give that a try to remove the dust.

[alacant]

On 04/03/2020 at 22:45, Adam1234 said:

focusing (really difficult

Hi

Nice shot.

To focus, choose your focal length, set the lens to auto and focus on the moon. Now set the lens to manual and tape the focus ring to prevent it moving. That's it.

HTH

Edited March 6, 2020 by alacant

[Spaced Out]

On 04/03/2020 at 21:45, Adam1234 said:

•  Any idea how to check if is indeed dust on the sensor and how I can clean it, or should I take the camera into the shop and get a professional to do it?

Many Canon cameras have a manual sensor clean option in the menu, I always try this first off. If that doesn't work then as others have said, mirror lock up (to expose the sensor), hold the camera upside down and use a rocket blower or compressed air. This helps to clear loose stuff.

For more stubborn dust stuck on the sensor I use sensor swabs and sensor cleaning fluid. I try to keep swab cleaning to a minimum and only do it if the dust is a real problem. It’s easy enough to do you just need the right tools and it works well to remove dust. There are plenty of tutorials on youtube to help with this method.

[Adam1234]

13 hours ago, Spaced Out said:

Many Canon cameras have a manual sensor clean option in the menu, I always try this first off. If that doesn't work then as others have said, mirror lock up (to expose the sensor), hold the camera upside down and use a rocket blower or compressed air. This helps to clear loose stuff.

For more stubborn dust stuck on the sensor I use sensor swabs and sensor cleaning fluid. I try to keep swab cleaning to a minimum and only do it if the dust is a real problem. It’s easy enough to do you just need the right tools and it works well to remove dust. There are plenty of tutorials on youtube to help with this method.

Thanks, I'll have a look in the manual to see if there's anything about manual sensor clean, I think I did see something in there.

[happy-kat]

On 04/03/2020 at 22:24, TerryMcK said:

Normally get rid of dust bunnies by taking flats and putting them in the stacking software. You can clean the sensor yourself with a blower brush or better still a can of compressed air specifically for cleaning photographic equipment. 

Everything I've read on here they are anything but just air and I wouldn't touch my camera sensor with one. A plain rubber bulb air blower works.

It's a modern camera in the menu will likely be a sensor mirror up option so the user can access to clean the sensor.

For focusing at OP I use an Android phone/tablet and the app DSLR Controller.

[assouptro]

Definitely dust bunnies. 
flats will help but I would get rid of them by the use of a blower or if that fails single use cleaning swabs like these.....

https://www.amazon.co.uk/dp/B00NIA545U/ref=cm_sw_r_cp_api_i_uP3yEb6K3GX8N

Don’t be scared to swab your Sensor, you aren’t actually touching the sensor, they have protective filtered glass over them so it’s that that gets dirty, I have stripped quite a few canon cameras down for modification and trust me, you won’t damage the sensor unless you get a screwdriver out and strip the camera down to get to the sensor first! 
Cheers 

Bryan 

[Starflyer]

On 04/03/2020 at 23:04, Adam1234 said:

Thanks, I'll have a look for some compressed air and give that a try to remove the dust.

I wouldn't use a can of compressed 'air' to clean a camera sensor. These are often a liquified gas of some sort, not air, and may contain other stuff that will mark your sensor if it comes out as liquid, which it often does.

Use a rocket type bulb blower.