Which Ultra Wide Fast lens for night sky?

Samyang/Rokinon 14mm

HKFEVER wrote in post #17128982
Tried the Samyang... but it is too soft, don't like it at all, the image away from the center is

I'd consider trying another copy. I picked up one a couple of weeks ago and it's nice and sharp wide open on my 6D:

IMAGE LINK: https://flic.kr/p/oFTR​uD

Hermelin wrote in post #17128992
Isn't IS a big big benefit for this type of photography. If so, I recommend 10-18 IS STM.
I think you will get lower ISO than the Tokina.

No,

IS whirling while on a tripod during a 20 second exposure is bad news.

Also, F4 and more narrow is too slow for this kind of stuff without the use of a tracker.

Very best,

HKFEVER wrote in post #17128982
Sorry guys, I forgot to mention that it is for FF body.
And I am looking for f/1.4

Currently checking on Canon 14/f2.8 II, Leica R 15/2.8 II, Zeiss 15 f/2.8, Nikon 12-14 is great but it is f/4.0 & can't use on EOS

Tried the Samyang... but it is too soft, don't like it at all, the image away from the center is

Heya,

F1.4 is going to be soft, even on a nice lens, for infinity focused night sky long exposure. There's a reason you don't see the people in the astro forum all using that speed aperture. They're not. If you need that level of speed, instead of wasting your money on a super fast aperture that will not net you anymore than 1 stop of light, you should instead be focusing on a tracker that will let you expand into MINUTES rather than seconds of exposure. You'll get exponentially better astro from this, than a 1 stop faster lens.

If the 14 F2.8 Rokinon was soft to you, then you had a bad copy or a severe problem before using MFA. Try it again, different copy. The Rok 14 is very sharp wide open, it's one of the most used astro lenses out there for a reason, even over the 14L by Canon. Also, the Samyang 24 F1.4 is another serious astro lens on full frame.

But ultimately, seriously, look into a tracker. Trackers will do better with any lens, than trying to constantly seek wider, faster, prime options for this. You gain one stop, ever. You're not going faster than F1.4 on this. F2 is ok. F2.8 is common. So, two stops? But you're still limited by TIME. Take away the time restriction, via a tracker, and suddenly your world opens up.

Here's an example of how a tracker takes away that time restriction. I did this setup in the astro forum to show people interested in astro that chasing the best ISO camera and fastest lenses will spend thousands and still only work within the confined 20~30 seconds that they can expose for. A tracker takes away that time limit. Then you are no longer gear dependent. And then you can use absolutely JUNK equipment and get more light than the fancy expensive stuff.

Here's a junk example, of what trash-gear can do, on a lowly entry level tracker:

Rebel XSi ($180 junk ISO 1600 performance) with an old adaptall2 Tamron 28mm F2.8 lens (old, slow, $9!). On an iOptron skytracker ($350 entry tracker).

IMAGE LINK: https://flic.kr/p/nS8k​WM

IMAGE LINK: https://flic.kr/p/nTUK​5c

IMAGE LINK: https://flic.kr/p/nzCy​TM

IMAGE LINK: https://flic.kr/p/nS8k​eV

IMAGE LINK: https://flic.kr/p/kRz9​wv

tracker is a great option. Unless you want to have trees or other landscape features in the image. Longer exposures don't work great for auroras either. But for deep sky objects and the milky way, hard to beat.

Nice images BTW

MalVeauX wrote in post #17129607
No,

IS whirling while on a tripod during a 20 second exposure is bad news.

Also, F4 and more narrow is too slow for this kind of stuff without the use of a tracker.

Very best,

All recent Canon lenses will detect the tripod and go into "tripod mode". I've never tried it for astro, though, and 20 sec might be too long. Switching off and doing ML and timer works fine too, of course.

FromCanon Europe ...
The early model lenses which do not have this automatic function and which should have IS turned off (ie lock the IS correction lens group in place) when mounted on a tripod include the following lenses:

EF28-135mm f/3.5-5.6 IS USM
EF75-300mm f/4-5.6 IS USM
EF100-400mm f/4.5-5.6L IS USM
EF300mm f/4L IS USM

Canon addressed the ‘feedback loop’ in later model IS lenses by introducing an algorithm to the IS detection system to automatically recognise when the lens is mounted to a tripod. When these lenses are mounted on a tripod and the shutter button is pressed halfway, the IS system kicks in and the image in the viewfinder can be seen to go through a very slow vertical shift for about one second.

If the shutter button remains depressed halfway the IS system detects the lack of motion and automatically switches into a special mode. In this mode IS detects and corrects for mirror slap and shutter movement at slow speeds, but not for ‘normal’ lens shake. There is no advantage to be gained in turning off the IS function or locking the mirror prior to exposure.

The Rokinon or Samyang 14mm is the go to lens fir widescape astrophotography. Look through the astro pictures section on this site and you'll find plenty of examples pictures.

The rokinon is good but with the lens corrections in LR you end up with about a 16mm FoV because of the distortion correction. Not saying its a bad lens, if you get a good copy it's incredibly sharp. I have been much happier with the Tokina 16-28 though.

Also, as far as 1.4 being soft wide open, although its not an UWA, my buddy uses the sigma 35mm 1.4 for milky way work, at 1.4, and its very sharp wide open. I'm guessing the 24mm they are supposed to release will perform similarly.

MalVeauX wrote in post #17129631
Heya,

F1.4 is going to be soft, even on a nice lens, for infinity focused night sky long exposure. There's a reason you don't see the people in the astro forum all using that speed aperture. They're not. If you need that level of speed, instead of wasting your money on a super fast aperture that will not net you anymore than 1 stop of light, you should instead be focusing on a tracker that will let you expand into MINUTES rather than seconds of exposure. You'll get exponentially better astro from this, than a 1 stop faster lens.

If the 14 F2.8 Rokinon was soft to you, then you had a bad copy or a severe problem before using MFA. Try it again, different copy. The Rok 14 is very sharp wide open, it's one of the most used astro lenses out there for a reason, even over the 14L by Canon. Also, the Samyang 24 F1.4 is another serious astro lens on full frame.

But ultimately, seriously, look into a tracker. Trackers will do better with any lens, than trying to constantly seek wider, faster, prime options for this. You gain one stop, ever. You're not going faster than F1.4 on this. F2 is ok. F2.8 is common. So, two stops? But you're still limited by TIME. Take away the time restriction, via a tracker, and suddenly your world opens up.

Here's an example of how a tracker takes away that time restriction. I did this setup in the astro forum to show people interested in astro that chasing the best ISO camera and fastest lenses will spend thousands and still only work within the confined 20~30 seconds that they can expose for. A tracker takes away that time limit. Then you are no longer gear dependent. And then you can use absolutely JUNK equipment and get more light than the fancy expensive stuff.

Here's a junk example, of what trash-gear can do, on a lowly entry level tracker:

Rebel XSi ($180 junk ISO 1600 performance) with an old adaptall2 Tamron 28mm F2.8 lens (old, slow, $9!). On an iOptron skytracker ($350 entry tracker).

IMAGE LINK: https://flic.kr/p/nS8k​WM IMG_5167 by Mwise1023, on Flickr

That junk pile collected this light over 2 minutes and 15 seconds (one exposure, no stacks, 2m15s exposure):

IMG_0788 by Mwise1023, on Flickr

Same thing, but with a cheap EF 40 F2.8 STM lens, again, 2m15s exposure, no stacking. This lens is a $115 prime new?

IMG_5171 by Mwise1023, on Flickr

Anyhow, again, I can't stress enough that a tracker, even a cheap one, is better than buying the fastest ultrawide and using a 6D. You'll get so much more from a tracker when you don't limit yourself to time. Your options open up tremendously.

16mm for 2m15s:

IMG_5174 by Mwise1023, on Flickr

35mm for 4 minutes at only ISO 400:

DPP_0791 by Mwise1023, on Flickr

Just examples, you can go longer.

I even did a long exposure with a 180mm prime for Andromeda. With junk.

Very best,

Thx, dude.

I will look into this seriously.
But I just bought Canon14/2.8II

jsecordphoto wrote in post #17129915
The rokinon is good but with the lens corrections in LR you end up with about a 16mm FoV because of the distortion correction. Not saying its a bad lens, if you get a good copy it's incredibly sharp. I have been much happier with the Tokina 16-28 though.

Also, as far as 1.4 being soft wide open, although its not an UWA, my buddy uses the sigma 35mm 1.4 for milky way work, at 1.4, and its very sharp wide open. I'm guessing the 24mm they are supposed to release will perform similarly.

Why would you bother correcting the Samyang 14/2.8's distortion for astro shots? You waste IQ and FOV

This is what I have with 16-35 II in 24mm with 30s at Lake Lousie

HKFEVER wrote in post #17132619
Thx, dude.

I will look into this seriously.
But I just bought Canon14/2.8II

Too late ...
But i use the EF 15mm f/2.8 fisheye, it's tack sharp corner to corner (for sky no need to "defish" and you can even manage to have straight lines from the land without defishing when you understood the fisheye )

Reservoir Dog wrote in post #17132646
Too late ...
But i use the EF 15mm f/2.8 fisheye, it's tack sharp corner to corner (for sky no need to "defish" and you can even manage to have straight lines from the land without defishing when you understood the fisheye )

I have 15 f/2.8 too

Please show some picture.

2 minutes, single exposure, only ISO 400, at F2.

85mm.

IMAGE LINK: https://flic.kr/p/kPpD​Si

MalVeaux^beautiful and very smart work.
Can we tell them the other good part---that if you're using a super wide...e.g. 14mm or wider...then you don't have to be religious about polar alignment either when using the SkyTracker! Yes point to north as best as possible, def. get your azimuth in close too, then image away