A clear winner in my opinion! Great review as always. I agree with stopping down to f2, quite the dramatic improvement. Now for the price is it that much better than the cheaper 135s?
Whether it’s worth the price depends on the person holding the credit card, hah! I wouldn’t buy it new strictly for astrophotography personally (I’m sure other, more flush buyers would), but it’s an amazing portrait lens that performs well in both arenas. Comparing it to the AF Samyang (which I think is a swing and a miss attempt to clone it) the Sony outperforms on every metric except price. For astro the Samyang has pretty noticeable coma and worse astigmatism. For conventional use the Sony has dual electromagnetically actuated rail-mounted focus groups which in addition to be lightning quick also help cut down on aberrations when focused at different distances. The Samyang features a single lens element for focus that’s “linearly” actuated via a worm gear driven by a humble stepper motor. That said, since coma doesn’t typically cause much issue close to the optical axis and would contribute to the blurriness of out of focus areas I think the Samyang is a good value for portrait use for those on a budget. When it comes to astrophotography the old, manual Samyang 135mm F2 is ironically better than the Samyang 135mm F1.8 if you win the Samyang QC lottery, but you have to stop it down a bit more. The older manual lens obviously isn’t suitable for genres where you need AF, but it’s fairly inexpensive and a good value for astro use. I just wouldn’t show up to the studio to do professional headshots with it. I’ll do an round-up comparing them now that the individual reviews are out. But to summarize my reply: as in all things, it depends!
I think the wedgie shapes on stars are an indication of a little pinching of the optics somewhere in the train. It's my understanding that that particular issue would likely be copy to copy dependent. I don't see that shape in my copy. I shoot this lens at 2.5 and it's outstanding. The only better lens I've tried is the Plena, which produces the same results as the GM@2.5 when it's at 1.8.
Thanks for the suggestion! Someone else suggested pinching as well, so it could be. But the pinching that I’m familiar with happens in a lens cell that has over-tightened set screws, and thus has a 3-lobed triangular shape geometrically tied to the location of the set screws. This issue seems to be radially oriented relative to the optical axis, and it’s something that I’ve seen in a few lenses at this point. Given the amount of time I’ve spent inside various lenses I’m at a loss for what could be doing the pinching since they don’t use the same element mounting structure as a telescope, outside of maybe an over-tight retaining ring. I’m not thrilled about the prospect of diving inside this lens, lol, but I might experiment with the issue using a cheaper lens.
Hi Would you say a tracker is a must to use the plena? Sorry if it's a stupid question, but I own the plena but not a tracker so just curious if it's enough to get me started 😊
There’s no stupid questions! Just answers you don’t have yet. A tracker is a non-negotiable for deep sky work, even with a moderate telephoto like a 135mm. Otherwise you’re limited to extremely short exposures that are insufficient for most things on the sky. There are a small handful of objects that are bright enough that you might be able to stack out a decent image from a few hundred super short exposures, but you’ll never be able to capture the dimmer portions or dimmer objects. When you see a really crispy image of a galaxy or nebula you’re often looking at minutes or more likely hours of combined exposure. And for that you need a tracker.
@@FerventAstronomy thank you very much for taking the time to give such a good reply 🙏 Well I guess there's no way around it - I need to look into a tracker. Seems like there's a lot of options out there.
@@H4VG44RD My experience is that if you're using a Plena, your going to want to get the best image quality out of that tracker. The smallest tracker I would recommend would be a Star Adventurer (not the mini) for 135mm. Even then, at 135mm, you are going to have some poor quality exposures here and there.The Star Adventurer GTI would be even better (it's on sale for $539 on BH right now) as it has Goto and you could grow into that and add guiding. Once you add guiding on that mount it's going to excel at 135mm. At 135mm, I wouldn't go smaller than the SA 2 trackers though. A SA mini, move shoot move, or MSM nomad will work okish, but you are going to be throwing away a lot of exposures due to imprecise tracking.
Bien cet objectif pour le deepsky surtout examiné en full frame 61 mpx à 400%. Pour le défaut constaté sur les étoiles brillantes , je pense à un pincement d'une ou plusieurs lentilles. Nous connaissons celà sur les réfracteurs lors d'une collimation et d'un serrage un peu fort. On dit optique trop serré dans son barillet. C'est une hypothèse pour cet objectif Encore merci
Wow! I already was in love with this lens for portraiture, but it's nuts to see it's this good for astro too 🤯
It really is!
i was looking up for some info about the Sony 135 GM and found your video, that was awesome and so full of details, thanks alot, cheers from austria!
That's great to hear! It helps validate the effort put into these, knowing that they're helping folks!
A clear winner in my opinion! Great review as always. I agree with stopping down to f2, quite the dramatic improvement. Now for the price is it that much better than the cheaper 135s?
Whether it’s worth the price depends on the person holding the credit card, hah! I wouldn’t buy it new strictly for astrophotography personally (I’m sure other, more flush buyers would), but it’s an amazing portrait lens that performs well in both arenas. Comparing it to the AF Samyang (which I think is a swing and a miss attempt to clone it) the Sony outperforms on every metric except price. For astro the Samyang has pretty noticeable coma and worse astigmatism. For conventional use the Sony has dual electromagnetically actuated rail-mounted focus groups which in addition to be lightning quick also help cut down on aberrations when focused at different distances. The Samyang features a single lens element for focus that’s “linearly” actuated via a worm gear driven by a humble stepper motor. That said, since coma doesn’t typically cause much issue close to the optical axis and would contribute to the blurriness of out of focus areas I think the Samyang is a good value for portrait use for those on a budget. When it comes to astrophotography the old, manual Samyang 135mm F2 is ironically better than the Samyang 135mm F1.8 if you win the Samyang QC lottery, but you have to stop it down a bit more. The older manual lens obviously isn’t suitable for genres where you need AF, but it’s fairly inexpensive and a good value for astro use. I just wouldn’t show up to the studio to do professional headshots with it.
I’ll do an round-up comparing them now that the individual reviews are out. But to summarize my reply: as in all things, it depends!
I think the wedgie shapes on stars are an indication of a little pinching of the optics somewhere in the train. It's my understanding that that particular issue would likely be copy to copy dependent. I don't see that shape in my copy. I shoot this lens at 2.5 and it's outstanding. The only better lens I've tried is the Plena, which produces the same results as the GM@2.5 when it's at 1.8.
Thanks for the suggestion! Someone else suggested pinching as well, so it could be. But the pinching that I’m familiar with happens in a lens cell that has over-tightened set screws, and thus has a 3-lobed triangular shape geometrically tied to the location of the set screws. This issue seems to be radially oriented relative to the optical axis, and it’s something that I’ve seen in a few lenses at this point. Given the amount of time I’ve spent inside various lenses I’m at a loss for what could be doing the pinching since they don’t use the same element mounting structure as a telescope, outside of maybe an over-tight retaining ring. I’m not thrilled about the prospect of diving inside this lens, lol, but I might experiment with the issue using a cheaper lens.
Hi
Would you say a tracker is a must to use the plena? Sorry if it's a stupid question, but I own the plena but not a tracker so just curious if it's enough to get me started 😊
There’s no stupid questions! Just answers you don’t have yet. A tracker is a non-negotiable for deep sky work, even with a moderate telephoto like a 135mm. Otherwise you’re limited to extremely short exposures that are insufficient for most things on the sky. There are a small handful of objects that are bright enough that you might be able to stack out a decent image from a few hundred super short exposures, but you’ll never be able to capture the dimmer portions or dimmer objects. When you see a really crispy image of a galaxy or nebula you’re often looking at minutes or more likely hours of combined exposure. And for that you need a tracker.
@@FerventAstronomy thank you very much for taking the time to give such a good reply 🙏
Well I guess there's no way around it - I need to look into a tracker. Seems like there's a lot of options out there.
@@H4VG44RD My experience is that if you're using a Plena, your going to want to get the best image quality out of that tracker. The smallest tracker I would recommend would be a Star Adventurer (not the mini) for 135mm. Even then, at 135mm, you are going to have some poor quality exposures here and there.The Star Adventurer GTI would be even better (it's on sale for $539 on BH right now) as it has Goto and you could grow into that and add guiding. Once you add guiding on that mount it's going to excel at 135mm. At 135mm, I wouldn't go smaller than the SA 2 trackers though. A SA mini, move shoot move, or MSM nomad will work okish, but you are going to be throwing away a lot of exposures due to imprecise tracking.
Bien cet objectif pour le deepsky surtout examiné en full frame 61 mpx à 400%.
Pour le défaut constaté sur les étoiles brillantes , je pense à un pincement d'une ou plusieurs lentilles.
Nous connaissons celà sur les réfracteurs lors d'une collimation et d'un serrage un peu fort.
On dit optique trop serré dans son barillet.
C'est une hypothèse pour cet objectif
Encore merci
Quelle que soit la cause, je suis très curieux de le savoir