FAQ 24-105 with Speedbooster Opinions?

[hopkins802]

Has anyone used the Sigma 24-105 f/4 with a metabones speedbooster with the FS5, FS7, or hell even the a7s in crop mode? Since the speedbooster allows another stop of light, we're able to essentially raise the aperture to f/2.8, but is this a true f/2.8? Is the image really soft when stopped all the way down? I mean, who wouldn't want a 24-105 f/2.8 for event coverage?

-Dan

 

[LennyLevy]

This has been discussed in depth awhile back. As I recall the general consensus is that the Sigma is sharper and probably has less chromatic aberration than the Canon. There seems to be confusion over the extent to which its parfocal. Some people have claimed that there's were. I tried 2 of them and though I wasn't expecting them to be perfectly parfocal and I use both Canon and Tamron 24-70's often, the focus changed so radically with the zoom on the Sigma that i felt it would hamper my use. Buy one and try it you can always return to B&H .

 

[hopkins802]

Please re-read the post. It's not about whether or not the Sigma is better or not.. It's about how it perform when used with a Speedbooster at f/2.8..

 

[hopkins802]

Basically, I have an A7sii, and I'm wondering if I would benefit from buying a speedbooster adapter and shooting in aps-c crop mode. This would allow the 24-105 f/4 to still have the same zoom range, but essentially at 1 more stop of light wouldn't it, making it an f/2.8 lens?

 

[stokstad]

My sigma 24-105 with metabones cine speedbooster ultra works well and looks sharp to me wide open. One of the better performing lenses with the booster in my experience.

 

[hopkins802]

My sigma 24-105 with metabones cine speedbooster ultra works well and looks sharp to me wide open. One of the better performing lenses with the booster in my experience.

Cool, thanks man! Do you see a pretty big difference in DOF and the amount of light let in at "f/2.8" with the speedbooster?

 

[Bern Caughey]

Is the image really soft when stopped all the way down? I mean, who wouldn't want a 24-105 f/2.8 for event coverage?

Closing down most any lens to it’s minimum aperture will induce diffraction which softens the image, but is still often done to create a Starburst effect when shooting into the Sun.

As you are asking about filming Events I imagine you meant Opened Up instead of Stopped Down. Haven’t used Sigma’s 24-105mm so cannot comment.

I mean, who wouldn't want a 24-105 f/2.8 for event coverage?

A SpeedBooster is a Focal Reducer & adding a Ultra to this Sigma will result in a 17-75mm f/2.8.

 

[hopkins802]

Closing down most any lens to it’s minimum aperture will induce diffraction which softens the image, but is still often done to create a Starburst effect when shooting into the Sun.

As you are asking about filming Events I imagine you meant Opened Up instead of Stopped Down. Haven’t used Sigma’s 24-105mm so cannot comment.



A SpeedBooster is a Focal Reducer & adding a Ultra to this Sigma will result in a 17-75mm f/2.8.

Right but the 17-75mm used in crop mode will be equivalent to about 24-105mm. I'm referring to using it at a wedding. Where yes, I'd like it closed down for parts of the day where I'm following moving subjects (ceremony) but then opened up during the reception where I need more light.

I guess I'll just have to try!

-Dan