Johan Borg
Senior Member
Somewhat inspired by this thread: https://www.dpreview.com/forums/thread/4765185
While considering buying Sigma 50mm F2 DG DN, I wasn't able to find a single user report or review that compares it directly to the 45mm F2.8 DG DN, so I thought I should write a few words now that I have both.
Before buying the Sigma fp with its 45mm F2.8 bundle in 2020, I came from a sequence of 41-45mm fixed lens cameras: Sigma DP2, DP2 Merrill and dp2 Quattro. All of them have spectacularly sharp lenses, corner to corner.
The 45mm F2.8 was a change, as it has two deliberate personalities: Wide open and up close it has a slightly softer, dreamy rendering, which makes it a lot more suitable for portraits than shooting test charts. Give it more distance or stop it down a bit and it sharpens up nicely.
One of the presumably good things about the 45mm is that the transition from in-focus to out-of-focus at F2.8 is super smooth, resulting in very natural looking photos. From the DP2 cameras I was used to - and appreciated - a more defined transition, so I often stop down to F4 for portraits with the 45mm to emulate that. This made me curious about the 50mm F2, with a hope that I could use it wide open more of the time.
First impression with the 50mm F2 is that it's very contrasty compared to the 45mm. So much so, that I may have to adjust down contrast even in the Sigma fp's Portrait Mode. It's also very sharp wide open, similar to the feeling from the Sigma dp2 Quattro.
One of the benefits of that sharpness is that I sometimes set my fp to APS-C mode, getting a 75mm equivalent focal length from the 50mm. For even more range, I have a Sigma FT-1201 1.2x teleconverter, giving the equivalent of 90mm F2.8 without changing the main lens. Then you *really* want the center to be truly sharp, and this is where I feel the 45mm was slightly lacking, wide open at portrait distance. The 50mm F2 on the other hand, is super sharp when combined with the FT-1201 and the TC is perfectly usable both in FF and APS-C modes, just adding a bit of vignetting in FF.
I have a Canon 250D (the close-up lens, not the camera) which I've rarely used with the 45mm, since it has a useful magnification for near-macro, but I'm going to need it a lot more often with the 50mm F2, since it has a longer minimum focus distance. The combination with the close-up filter works well, though. What - you may ask - are you using the 45mm for macro, isn't it soft at close range?! No, it's actually really sharp, you just have to stop it down, which you want anyway for macro.
I expected the 50mm F2 to have busier bokeh than the 45mm F2.8, and that seems to be the case, but of course you get a shallower depth of field at F2 than F2.8, so that compensates somewhat. With both cameras at F4, the 45mm wins.
It's hard to pick a winner between the two, as they have different strengths. For travel, the 45mm is a bit lighter and the wider angle is more versatile for city scenes. On the other hand, the tighter perspective of the 50mm (and sharper crops wide open) is better for people shots, which I do a lot of since I became father.
My engineer brain would choose the 50mm F2 DG DN for its overall quality, but my heart is with the one of a kind 45mm F2.8 DG DN. So no, I don't regret buying both, despite the obvious overlap.
While considering buying Sigma 50mm F2 DG DN, I wasn't able to find a single user report or review that compares it directly to the 45mm F2.8 DG DN, so I thought I should write a few words now that I have both.
Before buying the Sigma fp with its 45mm F2.8 bundle in 2020, I came from a sequence of 41-45mm fixed lens cameras: Sigma DP2, DP2 Merrill and dp2 Quattro. All of them have spectacularly sharp lenses, corner to corner.
The 45mm F2.8 was a change, as it has two deliberate personalities: Wide open and up close it has a slightly softer, dreamy rendering, which makes it a lot more suitable for portraits than shooting test charts. Give it more distance or stop it down a bit and it sharpens up nicely.
One of the presumably good things about the 45mm is that the transition from in-focus to out-of-focus at F2.8 is super smooth, resulting in very natural looking photos. From the DP2 cameras I was used to - and appreciated - a more defined transition, so I often stop down to F4 for portraits with the 45mm to emulate that. This made me curious about the 50mm F2, with a hope that I could use it wide open more of the time.
First impression with the 50mm F2 is that it's very contrasty compared to the 45mm. So much so, that I may have to adjust down contrast even in the Sigma fp's Portrait Mode. It's also very sharp wide open, similar to the feeling from the Sigma dp2 Quattro.
One of the benefits of that sharpness is that I sometimes set my fp to APS-C mode, getting a 75mm equivalent focal length from the 50mm. For even more range, I have a Sigma FT-1201 1.2x teleconverter, giving the equivalent of 90mm F2.8 without changing the main lens. Then you *really* want the center to be truly sharp, and this is where I feel the 45mm was slightly lacking, wide open at portrait distance. The 50mm F2 on the other hand, is super sharp when combined with the FT-1201 and the TC is perfectly usable both in FF and APS-C modes, just adding a bit of vignetting in FF.
I have a Canon 250D (the close-up lens, not the camera) which I've rarely used with the 45mm, since it has a useful magnification for near-macro, but I'm going to need it a lot more often with the 50mm F2, since it has a longer minimum focus distance. The combination with the close-up filter works well, though. What - you may ask - are you using the 45mm for macro, isn't it soft at close range?! No, it's actually really sharp, you just have to stop it down, which you want anyway for macro.
I expected the 50mm F2 to have busier bokeh than the 45mm F2.8, and that seems to be the case, but of course you get a shallower depth of field at F2 than F2.8, so that compensates somewhat. With both cameras at F4, the 45mm wins.
It's hard to pick a winner between the two, as they have different strengths. For travel, the 45mm is a bit lighter and the wider angle is more versatile for city scenes. On the other hand, the tighter perspective of the 50mm (and sharper crops wide open) is better for people shots, which I do a lot of since I became father.
My engineer brain would choose the 50mm F2 DG DN for its overall quality, but my heart is with the one of a kind 45mm F2.8 DG DN. So no, I don't regret buying both, despite the obvious overlap.
