Looking for feedback and advice re: initial attempts at Astrophotography

Hi everyone,

I'm on holiday outside of London and the stars are out in force. I was inspired by Marco's helpful tips here: https://www.dpreview.com/forums/thread/4326605 to have a go myself at some shots of the stars - a couple of my efforts below.

Would love some advice on whether there are things I can do to improve the editing, and/or the actual shooting method.

The milky way - not sure how I can make it clearer?

Taken in the back garden of the holiday home, similar question about improving the clarity/colour of the milky way

Thanks

ahodder wrote:

Hi everyone,

I'm on holiday outside of London and the stars are out in force. I was inspired by Marco's helpful tips here: https://www.dpreview.com/forums/thread/4326605 to have a go myself at some shots of the stars - a couple of my efforts below.

Would love some advice on whether there are things I can do to improve the editing, and/or the actual shooting method.

I am no expert on astro, but some thoughts;

• Your 30 second shutter speed is too long for APS-C & 22mm. Start with Rule of 200 - meaning 200 / 22mm = ±9 seconds (you could probably get away with 10 seconds). This will significantly reduce the star elongation.
• You stars are blurry, especially in the first photo. Possibly due to camera movement during the long exposure, but more likely due inaccurate manual focus. I generally use a FF, but I did try the M5 + 22mm once and found that the 22mm was challenging to accurately focus-by-wire. I am sure it can be done, but needs care and a number of test shots using 10x magnification during focusing, and maximum magnification when checking the test shots. You need a sturdy tripod for long shutter speed astro shooting, so if you are using a cheaper lightweight "travel" tripod, that may be contributing to the blurriness as well.
• Your stars are fairly blown out (no colour - all white, especially in the first shot) which is probably due to over-exposure due to long shutter speeds and high ISO. It is often better to expose less and "stretch" in PP - have a look at Roger Clark's clarkvision.com for tips on PP. IMO anything more than ISO 1600 on APS-C tends to result in a more-than-desirable level of noise, but everyone has their own level of tolerance for noise.
• It looks like the darker patch in the first shot may be the core of the MW, but it completely lacks any colour. This may be due to using the "wrong" WB. The general thought is that using the "Daylight" WB setting produces a more natural and colourful result. This is more obvious with the "blue" image in the second shot.

The milky way - not sure how I can make it clearer?

Taken in the back garden of the holiday home, similar question about improving the clarity/colour of the milky way

Thanks

This is a fairly down and dirty single shot exposure with some basic light PP - I just haven't got around to putting more effort into it yet.

It was taken at Mt Cook in New Zealand - Canon 6D ii, Samyang 14mm f2.4 XP, Sirui CF tripod, basic editing in Canon's DPP, single shot. Shutter speed 20 seconds, f2.8, ISO 6400 (which was probably too high - should have used maybe 1600 & boosted more in PP) & Datlight WB. On FF Rule of 300 is recommended, and this is 20 x 14mm = 280 and the stars are reasonably round. My focus wasn't perfect (maybe because it was around 0°C at the time).

It is certainly not a great shot but it does show what kind of colours could/should be showing in the MW, even with a basic un-tracked single exposure  - a much "warmer" image.

Canon 6D ii, Samyang 14mm f2.4 XP

Colin

Use sequator. It is a very useful freeware (no ads) software.

It allows you to stack multiple shots, compensating the movement of the stars.

Take a lot of pictures, and the last photo take with caps on (completely dark). This will be your noise photo.

You can input CR3 files, that helps a lot in details.

So, at the end, your final picture will be 10min or 15 min exposure picture.

Sequator can be found here: https://www.softpedia.com/get/Multimedia/Graphic/Graphic-Others/Sequator.shtml

Advi wrote:

Use sequator. It is a very useful freeware (no ads) software.

It allows you to stack multiple shots, compensating the movement of the stars.

Only if you get the basics right and use an appropriate shutter speed. It doesn't compensate for star movement at all, but if you take a bunch of shorter exposure shots that don't show trailing, you can stack them together to reduce noise.

Take a lot of pictures, and the last photo take with caps on (completely dark). This will be your noise photo.

Most modern cameras have smarts that mostly negates the need for darks (at least according to Roger Clark).

You can input CR3 files, that helps a lot in details.

Good point - shooting in RAW for astro is very important if you want to stretch the exposure.

So, at the end, your final picture will be 10min or 15 min exposure picture.

I am not sure that this is true really. The astro gurus (I am not one) do speak of a "combined" exposure time after stacking, but AFAIK it is more of a reference to noise reduction due to stacking multiple shots rather than a true extended exposure time.

I think with DSS (another stacking programme) there is a reference to a noise reduction of the square root of the number of shots stacked - for example, 4 shots gives 1/2 the noise, 9 shots gives 1/3 the noise, 25 shots gives 1/5 the noise etc.

Sequator can be found here: https://www.softpedia.com/get/Multimedia/Graphic/Graphic-Others/Sequator.shtml

Colin

Andy01 wrote:

Advi wrote:

Use sequator. It is a very useful freeware (no ads) software.

It allows you to stack multiple shots, compensating the movement of the stars.

Only if you get the basics right and use an appropriate shutter speed. It doesn't compensate for star movement at all, but if you take a bunch of shorter exposure shots that don't show trailing, you can stack them together to reduce noise.

This program stacks photos. And you can select which part of the picture is ground and which part is sky.

Each picture will be divided in 2. Ground does not move, sky does. Sky needs to compensate for being moving, ground does not.

Take a lot of pictures, and the last photo take with caps on (completely dark). This will be your noise photo.

Most modern cameras have smarts that mostly negates the need for darks (at least according to Roger Clark).

This software requires a noise picture.

Hello - Excellent Photograph.  

ahodder wrote:

Hi everyone,

I'm on holiday outside of London and the stars are out in force. I was inspired by Marco's helpful tips here: https://www.dpreview.com/forums/thread/4326605 to have a go myself at some shots of the stars - a couple of my efforts below.

Would love some advice on whether there are things I can do to improve the editing, and/or the actual shooting method.

The milky way - not sure how I can make it clearer?

Taken in the back garden of the holiday home, similar question about improving the clarity/colour of the milky way

Thanks