It's not distortion you see with ultra wide angles, it's just an extreme field of view as with any UWA. The effect isn't so noticeable when shooting the Milky Way.I had thought about a 14mm, but does that not distort the perspective as often is seen in daylight photography ?
I had thought about a 14mm, but does that not distort the perspective as often is seen in daylight photography ?
The moustache distortion on the Samyang is disappears with the LR preset, but even without it unless you're shooting a seascape or very straight lines half the time you don't see it.Theres a distortion pre set for the Samyang in LR CC.
As Nod said try them both. 28 may not give you the view that you want. Several images stacked works well to reduce noise.
Samyang seems to distort the horizon most noticeably
The moustache distortion on the Samyang is disappears with the LR preset, but even without it unless you're shooting a seascape or very straight lines half the time you don't see it.
I've seen many great captures using the Samyang 14mm f2.8
I'll shout up for the Samyang 24mm f1.4 -The COMA is minimal, and for full MW shots, you would need a wider FOV than 14mm would give you - Merging a pano from shots would be a lot easier with the 24mm
Plus f1.4
Stopped down its one of the sharpest UWAs I've used (no idea what aperture this was though as its non reporting on the Canon!)Samyang is a great lens but it does have a heavy moustache distortion as Jim pointed out. If you compare it with the Canon 14mm f2.8 there is a significant difference it but, as with a lot of things, the Canon is expensive. The Samyang does exhibit some coma in the corners at f2.8. I don't know how it performs stopped down as I have not tried it. Something to try on a clear night with a tracker to allow an exposure of a couple of minutes.
This is a very good point and touches on something that has not been mentioned yet which is largest clear aperture.
A 50mm 2.8 lets in more light than a 20mm 2.8.
The downside is without tracking your exposure time is limited more by the longer focal length.
As Matty has pointed out the sweet spot is 24mm 1.4.
I bought a sigma art 35mm 1.4 which is immense at gathering light from stars but to be honest it is too long. So far for Mac I have not found any software that stacks and or merges multi row panos to my satisfaction.
If you have deep pockets and don't want to merge then the canon 11-24 f4 is considered a beast for Milky Way shots, partly due to low coma at maximum apertures.
Look coma up by the way.
This guy shows the effect on stopping down for coma
http://intothenightphoto.blogspot.co.uk/2012/09/overcoming-coma-in-starry-night.html
I can't see 24mm being wide enough for me. Will plod along with what I've got between the 17-40 and the Samyang 14mm. I've got a tracker so not limited by exposure time on a wide angle really.
Your laughing then, a tracker and a wide angle is the best option in my opinion. You can always do an exposure without tracking and just overlay and paint through the non blurry foreground for the best of both (which I'm sure you know but for others benefit)
Which tracker have you got? I'm interested in one but so far j have been disappointed with light pollution to take Astro too seriously...