Time to blow your kid's college fund? - Sony FE 50mm F1.2 GM Astrophotography Review

[@vacciniumaugustifolium1420]

Ive been looking for months to find any serious review for Astro about the only GM at F1.2 we have so far. this is truly a golden video for me, thank you so much!

[@FerventAstronomy]

Y’know, someone’s gotta take on the onerous burden of -buying- trying out all these lenses, and gosh darn I guess that person’s me. 😂

[@flexplexico99]

That looks like an awesome lens! Great review.

[@FerventAstronomy]

Thanks! It’s not a cheap one, but definitely an interesting lens for Astro.

[@fotovylety]

I have bought 50/1.2gm specifically for astro landscapes and I am happy with the performance at f/2 🙂. All corners have similar PSF. It is also great for portraits. Before that I have had 50/1.8za in this focal range and that was good for portraits, but terrible for astro. I tried 35gm, but copy I got was bad for astro.

[@nat-lj8kt]

@@fotovylety i got 35mm twice. First one was sent back to amazon. Second one perfect, even better than 50mm 1.2 GM if you want that edge to edge sharp and clinical look :)

[@nat-lj8kt]

@@fotovylety dont get me wrong 60mm 1.2 GM is the magical lens for me but for astro 35mm GM if not defective is better I feel also because of frame length. 50mm too narrow for me anyway if it's an astro landscape and I hate to composite too much

[@FerventAstronomy]

Glad you found the right lens for you!

[@nat-lj8kt]

Do you have differences in the 4 corners on the nature of the astigmatism? Different shapes etc. Sony GM lenses can have weird brhaviour sometimes (not simple decentering or tilt, something due to all the aspherics probably)

[@FerventAstronomy]

All lenses will experience asymmetry to different degrees, fast lenses especially, and even within the same model no lens will have the exact same reproduction as any of its siblings. This seems to scale with more complicated optical formulas - when there’s 15 lens elements, for instance, there’s a ton of room for variation. Sadly, a perfect anastigmat with a fast aperture that can hold up to the combination of astrophotography and high resolution imaging isn’t something we’re currently blessed with. Maybe one day?

[@sixuanli8583]

Hi Fervent, great reviews. Just curious about the dark line around bottom one third of your frames which seems to be consistently seen in several of your lens test videos. Is that something to do with ur camera?

[@FerventAstronomy]

I have to admit, I’m not sure what you’re referring to, I’m not seeing it on this end

[@sixuanli8583]

@@FerventAstronomy Like the line in the images in 5:52, 6:19, 10:37 and 19:15. A line that pass through the whole frame from left to right in the bottom one third of the image I guess. Seems more obvious in the theater mode than full screen mode. Is that something you also see?

[@FerventAstronomy]

Nothing on my end. Might be something to do with the way your graphics processor is interacting with the data

[@sixuanli8583]

@@FerventAstronomy Thx!

[@MarkusGebhard]

thank you for your reviews, they are really helpful. Have you ever tested the Sigma 40mm f/1.4? I've heard only good things about it

[@fotovylety]

@@MarkusGebhard I heard from two photographers that use Sigma 40/1.4 both agreeing their's is shifting focus when tilting up (which they do for multi row panoramas) so they have to refocus which is annoying. Otherwise it is great for astro.

[@MarkusGebhard]

@@fotovylety That would my use case for it too. I'm reading this for the first time here. Lets hope thats not a design flaw

[@FerventAstronomy]

I bought the 40mm for testing a few weeks ago, just haven’t had a chance to get out with it yet. To touch on the comments about focus shifting: the focus mechanism is the traditional manually coupled type, using rollers and cams, and from the optical formula diagram the focus group looks massive. As such it’s not surprising to hear that shifting the position might cause focus to slip. It’s possible that taping the focus ring might help, however the manual focus ring is coupled via a friction clutch and that will allow slippage if the force is great enough.

[@MarkusGebhard]

@@FerventAstronomy Thank you for the explanation! Looking forward to hearing your opinion on this lens

[@terrylovejoy3147]

I guess you get what you pay for. Performance at 50/1.2 is impressive :)

[@FerventAstronomy]

It tends to work out like that, to the detriment of bank balances lol