Looking for feedback and advice re: initial attempts at Astrophotography

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