IBIS with non-native zoom question

[olsonbock623]

Hi folks. I've got a GH5 on preorder, and would like to pair it with a Nikon speedbooster and Sigma 18-35.

As I understand it, the Nikon speedbooster is non-electronic so the camera won't automatically adjust the IBIS focal length setting (whereas the Canon EF version may do so?).

So my question is, does anyone have firsthand experience with how the IBIS on a G85 or GX85 works with a Nikon mount Sigma 18-35 lens? If you set the IBIS halfway, say at 25mm, how well does it stabilize? I'd rather not shell out for a Canon EF speedbooster since I have no other Canon EF lenses, but if it works much better with IBIS on the GH5 I may have to do so. 

Thoughts?

[fuzzynormal]

1 hour ago, olsonbock623 said:

how the IBIS on a G85 or GX85 works with a Nikon mount Sigma 18-35 lens?

As you know, you have to manually set IBIS to the focal length for "dumb" adapters.  The IBIS will work give or take a few mm, so you have a bit of a mm "window" to work with, but not a lot.  It gets wobbly the farther from the accurate mm tandem-setting.  That said, setting your focal length and then manually adjusting the IBIS to match take about 3-5 seconds, so you can always just do that.

[olsonbock623]

Thanks for sharing your observations. I'm looking to use this setup for run-n-gun documentary and wedding work, so those 3-5 seconds to adjust the setting could mean missing the moment. Sounds like I might be better off with the Canon EF version.

[fuzzynormal]

Or get a M43 native lens.  Or, better yet, just shoot with a fast prime?  

Lots of folks seem to think that a variable is the only way to go with video shooting.  However, there's a quality that leans "cinematic" when the focal length stay consistent through a shoot/footage.  On a lot of my work I often favor one lens and that's it.  Something around a 50mm FF equivalent would be perfect for weddings.  Not too long, not too short.  Great for shallow DOF.

Of course, that's not the advice you're interested in!  Good luck, regardless.

[olsonbock623]

Thanks. I've been shooting weddings on hacked GH2s with fast primes for a few years. I really like the look of shooting with primes, but would like the convenience to be able to quickly zoom out and grab a wider shot of the action or get an establishing shot without switching lenses. I'd prefer something faster than the native f2.8 lenses for filming dark receptions and having the option of shallower DOF.

[noone]

Canon IS lens with a smart adapter is good too. 

You can use the lens with IS and a non focal reducer smart adapter or with IS and a focal reducer/speed booster.

One thing though is that EF-S lenses might not play well with a Speed Booster (so a cheap Canon APSC IS kit lens maybe not a choice for a Speed Booster but ok with the non focal reducer).