Hi all,

My current setup is Sony A7M4 and Sony 90mm marco (Tarmon 90mm can be borrowed from my friend), since my favorite is macro to super marco then normally I will put the focal range switch on 0.28-0.5m, which can reduce a lots of uncessary focusing move. Now my MFO-3 is on the way, I have already checked the review videos and discussion threads in the forum, but still not so sure what would be the best option for the focal range switch setting. Especially the new Sony 100 marco is also in my wishlist🤣

Let me try to list all the possibilites and please share your experience and suggestions

• Daylight diving without mfo-3, focal range 0.28-0.5

• Daylight diviing with mfo-3, focal range 0.5-infinity or full range?

• Blackwater diving with mfo-3, focal range 0.5-infinity?

Thanks~

You want the full focus range on the lens in all circumstances with the MFO3. Infinity focus on the lens corresponds with an object about 1.5m away so if you engage the focus limiter you will be restricted to a few cm from the lens. You could use 0.5 to infinity quite likely but you can't get 1:1 if you take the MFO3 off.

If you are diving and taking the MFO3 on and off you want to be in full range (unless you are able to change focus limiter while UW ) .

1 hour ago, Chris Ross said:

You want the full focus range on the lens in all circumstances with the MFO3. Infinity focus on the lens corresponds with an object about 1.5m away so if you engage the focus limiter you will be restricted to a few cm from the lens. You could use 0.5 to infinity quite likely but you can't get 1:1 if you take the MFO3 off.

If you are diving and taking the MFO3 on and off you want to be in full range (unless you are able to change focus limiter while UW ) .

Thanks Chris,

As my typical shooting objects are all tiny critters no larger than 5cm on daylight diving. I have tried full range focus but it took me more time to find and foucs on the certain object, especially for the fast moving ones.

So maybe I can still use my previous setup on daylight diving, use SMC-1 instead of MFO-3, but keep MFO-3 attached all the way during the blackwater, and set focus range as infinity?

2 hours ago, flowdesign said:

Thanks Chris,

As my typical shooting objects are all tiny critters no larger than 5cm on daylight diving. I have tried full range focus but it took me more time to find and foucs on the certain object, especially for the fast moving ones.

So maybe I can still use my previous setup on daylight diving, use SMC-1 instead of MFO-3, but keep MFO-3 attached all the way during the blackwater, and set focus range as infinity?

it's up to you, the main point is you need full range for the MFO3 to work properly. I typically set my macro lens for full range and mount the MFO3 whenever I want to shoot something larger. I'm not sure how the SMC-1 would be used instead of the MFO3 as they have completely different purposes. Have you tried pre-setting the lens for close operation before approaching your subjects? I'm not familiar with the 90mm/A7RIV combination, I've heard the new bodies have better AF with the 90mm lens.

As you generally don't have access to macro range switches during a dive it needs to be set to allow infinity focus, I don't see much point in setting the switch to 0.5m to infinity on a dive where you are wanting to do macro and use the MFO3 - you lose the ability to get close for small things and potentially limit what you can do with the MFO3.

As for blackwater, max magnification with MFO3 is 0.8x and the subject would be touching the front element So I think you'll need the full range to shoot small things? For subjects as greater distances the macro lens is operating at 2m to infinity range where most macro lenses will AF better.

Thanks Chris! Will check the the setting combination with MFO-3 in my next dive trip