20 or 24mm for astrophotography?

[DavidBrother]

I'm stuck in chosing between:

* Sigma 20mm f1.4

* Sigma 24mm f1.4

* Sony 24mm f 1.4.

The Sigmas cost about the same, and can easily be found secondhand for a rebate. The Sony is much more "perfect" (?), but cost the double, at least, and can't be found in the secondhand market that easily.

I've tried a 16 or 15mm, but found that just too wide, I think I'd rather go with a lens that occasionally can be used for other purposes.

That would lead me to the 20 mm 1.4 as the obvious choice... BUT. it's large and heavy. It would be left at home when I'd go camping.

Lower weight and price would inch me towards the sigma 24, but then again it's larger and not weathersealed like the Sony. And I wonder if 24mm would lead to too much stitching, eg. too narrow angle of view...

It will be used on a a7r2.

So...any input?
Cheers.

 

[Reefdiver]

Check out Allyn Wallace’s review of the Sony 24 f1.4. Best ever Astro lens? But priced as such.

 

[mattjp1]

If only for astro and the corners are really important to you, then the Sony 24GM. It has low coma.

If you prefer a 20mm, I would go with the new Voigtlander Nokton 21mm 1.4. For landscape/astro, there is no real need for autofocus; manual option could save you weight while keeping a large aperture and image quality (the Nokton was rated -slightly- better than the Zeiss Loxia).

 

[DavidBrother]

Thanks for the answers, guys!

That Nokton looks nice, but can't find it retailing in my country. And as for the Sony, well, it's on the top of my list, if only money was no subject...

No love for ths Sigmas?

(My headline is a bit inaccurate, I think everything from 18-24 would be nice. Also been considering the Samyang 18 f2.8, but would prefer more light. 18 f1.8 would have been nice....)

 

[SeanHew]

Sony 24 GM is the way to go for best performance. The sigma lenses have various issues such as coma, etc.

I've been using the Batis 18 and I'm pretty happy with it. Great technical qualities for astro, plus it is light for hiking/backpacking. Only issue is the the 2.8 aperture and a bit of vignetting wide open but it has been the best all around package for me.

 

[mattjp1]

Thanks for the answers, guys!

That Nokton looks nice, but can't find it retailing in my country. And as for the Sony, well, it's on the top of my list, if only money was no subject...

No love for ths Sigmas?

(My headline is a bit inaccurate, I think everything from 18-24 would be nice. Also been considering the Samyang 18 f2.8, but would prefer more light. 18 f1.8 would have been nice....)

Sigma does excellent lenses, if you can take the weight.

If you drive to your shooting location, then set-up your tripod etc.. then it should be OK. If you hike or just walk though, a 1kg lens isn't really fun to carry.

 

[Dominic Ryan]

I love my Sigma 20mm f1.4, it is my main astro lens on my a7S. I wanted wider than 24mm, but not so wide as edge distortion became an issue. It does show some coma in the far corners, but as I use it mainly to produce time-lapse.

As a hobbyist, no way I could justify the GM at twice what I paid for the Sigma. The Voigtlander might be worthy option, the cheap option I looked at for a while was the Viltrox 20mm f1.8. If I hadn't gotten onto a 20% off coupon on eBay for the Sigma, I likely would have gone that route.

 

[Kurgo]

Thanks for the answers, guys!

That Nokton looks nice, but can't find it retailing in my country. And as for the Sony, well, it's on the top of my list, if only money was no subject...

No love for ths Sigmas?

(My headline is a bit inaccurate, I think everything from 18-24 would be nice. Also been considering the Samyang 18 f2.8, but would prefer more light. 18 f1.8 would have been nice....)

Sigma wides have the nasty tendency to badly correct coma, which is why they're not usually the first option

A 20 1.4 coma https://www.lenstip.com/457.7-Lens_...f_1.4_DG_HSM_Coma__astigmatism_and_bokeh.html

A 24 1.4 coma https://www.lenstip.com/430.7-Lens_...f_1.4_DG_HSM_Coma__astigmatism_and_bokeh.html

It really depends on whether you're ok with that level of coma or not. I personally wouldn't but there are also plenty of people who use the Nikkor 20 f/1.8 wide open and I wouldn't do that either because even without going 100% I can see the coma smearing just fine. Again, it depends on what you deem acceptable.

A lens I've read some good things about (not seen any decent thorough tests of, though) is the Samyang 20 f/1.8. Its coma correction seems to be better than the Sigmas, it's much smaller/lighter and has decent enough corners for astro. Again, you'd have to look into it a bit more though.

If money was no object, the Sony 24 is just excellent all around, that goes without saying.

 

[IDoLikeCameras]

The 24mm is a tad narrow but the quality is worth it to me - and its still wide enough anyway, i don't really stitch anything

The other thing is that the lens is great for other use cases too, so sharp across the range..

 

[DavidBrother]

Been looking around dxomark. Excellent sharpness on the sigmas (Canon mount though). Noticably sharper than samyang wide open. I wonder if I can live with that coma (and instead crop in)...

https://www.dxomark.com/Lenses/Comp...-Canon-EOS-5DS-R__680_1009_1510_1009_473_1009

 

[mattjp1]

Been looking around dxomark. Excellent sharpness on the sigmas (Canon mount though). Noticably sharper than samyang wide open. I wonder if I can live with that coma (and instead crop in)...

https://www.dxomark.com/Lenses/Comp...-Canon-EOS-5DS-R__680_1009_1510_1009_473_1009

Dxo is a great technical source but you might want to check Flickr for actual examples. I looked at a few, it seems the lens has a bit of coma but you really need to look for it. If your goal is to avoid coma at all cost, you might want to get the 24GM and your problem is solved.

 

[moficera]

Been looking around dxomark. Excellent sharpness on the sigmas (Canon mount though). Noticably sharper than samyang wide open. I wonder if I can live with that coma (and instead crop in)...

https://www.dxomark.com/Lenses/Comp...-Canon-EOS-5DS-R__680_1009_1510_1009_473_1009

When I look at the coma test at lenstip.com it is really bad for the 24mm Art, worse than the 50mm or 35mm. I have the 35mm Art and 50 mm Art and while the 35mm is fine (not great) wide open, I wouln'd use the 50mm unless stopped sown to f/2.8 as bright stars can ruin the whole image by becoming a cross (or you have to retouch them).

Also look at this:

Sigma 24 F/1.4 Exhibits Significant Coma

I picked up one of these lenses a couple of days ago, hoping it would become my go-to lens for Landscape/Astrophotography. The results were not so good. Although the lens was exemplary for daylight casual shooting, there is significant COMA towards the edges, some of the worst I have...

www.dpreview.com

 

[Dan_168]

I'm stuck in chosing between:

* Sigma 20mm f1.4

* Sigma 24mm f1.4

* Sony 24mm f 1.4.

I've tried a 16 or 15mm, but found that just too wide, I think I'd rather go with a lens that occasionally can be used for other purposes.

That would lead me to the 20 mm 1.4 as the obvious choice... BUT. it's large and heavy. It would be left at home when I'd go camping.

Lower weight and price would inch me towards the sigma 24, but then again it's larger and not weathersealed like the Sony. And I wonder if 24mm would lead to too much stitching, eg. too narrow angle of view...

It will be used on a a7r2.

So...any input?
Cheers.

I do a quite a bit of Milky way stuffs and so far it seems like I use the Sigma 14 1.8 Art and Laowa 15 the most, but you already said 15 and 16 is already too wide, so those will not be the lens for you, but for me is totally opposite, sometime I have t do multiple shot and stitch together to get even wider than a 14mm, like when I need to get a full milky Way arch over Half Dome in Yosemite or something like that.

I personally have no love in the Sigma 20 and 24mm because of the Coma, I like my Nikon 20 1.8G a lot better, but after playing with the new Voigtlander 21 1.4, I decided to replace my Loxia 21 with the Voigtlander before next season, for general landscape the Loxia works jus great, but I still like the Voigtlander's 12 point sun star better than Loxia's 10 point, but I won't need any new Milky way lens until the next Milky Way season until March next year.

For the 24mm, again this FL is NEVER wide enough for me, but I am about to get the Sony 24GM, for what I have seen so far, this is one of the best Astro lens, low coma, sharp wide open, nice edge sharpness wide open, all the stuffs you want for a astro lens, again I will just do multi row stitching instead of one single shot, I got all the pano gears, so, easy enough. the only thing is I hate using AF lens for astro, the MF operation on all those Sony lens is just sucks big time, just for tat reason, I may go with the new Voigtlander 21 1.4, will see, I will have both next season for sure.

Besides Astro, the 24GM also offer very nice bokeh, well, nice for a 24mm lens so I can use it for environmental portrait as well.

 

[IDoLikeCameras]

Ive had the laowa and ive the sony 24gm, while i liked the wider angle, the IQ difference was night and day (i returned the laowa).

The build quality and everything else was also better on the sony. Then again the sony price is almost double ;-)

 

[DavidBrother]

Yeah I'd go for the Sony if I had the money...

Just found out that the excellent landsacpe-vlogger Mads Peter Iversen https://www.youtube.com/channel/UCrWU2BpF6zvRFnkYHDDYHDg

actually uses the sigma 20, and he says that some find the coma bad, but he doesn't. The pictures he took with it are awesome. He also made it clear that it's not a daily carry-around lens that only comes in the bag when certainly needed.

 

[Karafuru]

If you crop the 20mm Sigma / 21mm voigtlander to match the field of view of the 24mm Sony GM, they have the same levels of choma more or less ;-)

 

[Dan_168]

Ive had the laowa and ive the sony 24gm, while i liked the wider angle, the IQ difference was night and day (i returned the laowa).

The build quality and everything else was also better on the sony. Then again the sony price is almost double ;-)

Just received my Sony 24GM, have nt get the chance to do any Milky way shot yet. as for built quality, I actually think the Laowa feels much more solid, while the Sony feels like a cheap plastic lens, and as for image, I consider the Laowa very very good, here here is one shot I found on my Online Album from the Laowa 15. I think I probably i still will use the Sigma 14 1.8 and Laowa 15 more than this new 24GM for my Astro shot due to much narrower 24mm Focal length.

 

[Dan_168]

Ive had the laowa and ive the sony 24gm, while i liked the wider angle, the IQ difference was night and day (i returned the laowa).

The build quality and everything else was also better on the sony. Then again the sony price is almost double ;-)

Oppsss, Sorry I got this discussion mixed with the other one I just participated with the Laowa 15 vs Samyang vs Sony. yeah, I hav no love at all for the Sigma 20 when it comes to Astro.

 

[IDoLikeCameras]

• Dan_168 wrote:

Ive had the laowa and ive the sony 24gm, while i liked the wider angle, the IQ difference was night and day (i returned the laowa).

The build quality and everything else was also better on the sony. Then again the sony price is almost double ;-)

Just received my Sony 24GM, have nt get the chance to do any Milky way shot yet. as for built quality, I actually think the Laowa feels much more solid, while the Sony feels like a cheap plastic lens, and as for image, I consider the Laowa very very good, here here is one shot I found on my Online Album from the Laowa 15. I think I probably i still will use the Sigma 14 1.8 and Laowa 15 more than this new 24GM for my Astro shot due to much narrower 24mm Focal length

Well that's, like, your opinion man. Metal doesn't make the build quality for me. Tolerance does.

That said iq is where its at. Having the near same iq at f1.4 and f2.8 or basically no corner softness is pretty nice. The coma difference is also going to be hard to deny. I note that you say you received but haven't used the lens, yet prefer the other lenses. How about you go try it before you make up your mind!

 

[alma175w]

Tokina Firin 20 is supposed to be pretty stellar, especially for an astro only lens. There are two versions, MF verses AF, but they share the exact same optics. Both lenses have $100 discounts available right now. SO, you can get the MF for $599 and the AF for $849.

I haven't used them, but Stan Moniz owns the AF version AND the 24GM, and the Tokina produces some of his best images, IMO.

I also own the 24GM, and it is my go to astro lens. Wish it was a bit wider, I'm actually really tempted by that MF version of the Tokina, but holding out for rumored/fabled ultra-wide GM prime...