Pat F 4119 Loc: Branford, CT

Hi all, you have always been so helpful in the past, and I’m hoping you might be able to point me in the right direction to resolve my current dilemma. Recently, and this has been happening intermittently for a while, I was shooting in the studio with my a 7R3 and the Sony 50mm f1.4, set to f5.6, using flexible spot focusing, with Godox strobes, in a fairly dimly lit studio, and at least 50% of the time, the auto focus would hunt and hunt and not able to lock onto the subject. The issue was so pronounced that I was forced to switch to manual focus just to get through the shoot. When I switched to my Sony 85mm f1.4, the issue seems to be resolved, so I’m guessing there’s some thing going on with that lens, but I would need to do more testing.

So, my question is, has anyone had a similar experience, or if I could be pointed in the right direction regarding my next steps in resolving this issue, it would be greatly appreciated. Perhaps it’s a lens firmware issue? As always, any help would be tremendously appreciated, thanks!

UTMike Loc: South Jordan, UT

I have not had this problem with my 7R3, but my outside AF shooting improved when I downloaded the latest firmware update. Have you done that?

Pat F 4119 Loc: Branford, CT

Thanks for responding, but yes, I have the latest firmware.

User ID

There should be a menu choice between CDAD and PDAF. In general, CD is more likely to hunt but you have two special cases, the dim room and the 1.4 lens. So the general rule may not apply. Can only guess why the 85 is no problem ... there are crazy Sony variables.

IIRC the menu line will say “AF Mode”. Whichever mode you’re in try the other. You’re in studio, so BBAF is assumed.

If there’s a menu line for AF Speed, slow it down. The fuzzy mess of a defocused 1.4 lens offers too little data for the sensors to latch onto if the lens focuses rapidly.

Now the tricky part :-( The lens might do its AF at 1.4 or 5.6. This varies with lens model, body model, type of AF in use, etc etc. Sonys are really insane on that score. Hopefully you know a whole lot about cameras as devices, cuz there’s no real advice except to try many combinations of AF-C, AF-S, CDAF, PDAF, zone, pinpoint, etc etc etc etc and watch the iris. Despite the dim room, you want it to do AF at 5.6 so the defocused image makes more sense to the sensors.

Other solutions would be a flash or trigger with an AF Assist beam, or ditch the fast lens, or just use MF. If you have a kit zoom, it’s prolly about f/4 at 50mm and should AF well by your modeling lights. Makes no sense to use a 1.4 with strobes.

gwilliams6

Newer Sony and third party E-mount lens will open up to their max aperture briefly to help focus and then stop down to the selected f-stop. That 50mm f1.4 lens is excellent but has been around since July 2016. My bet is that lens was trying to focus in dim light at f5.6. You still can see it bright in the EVF because of the automatic gain features. In that situation it makes a huge difference the focus settings and zones you choose in the camera menu to help that lens focus on your subject at f5.6 in dim light. Your 85mm f1.4 probably focuses at f1.4 in dim light and then stops down to its chosen f-stop.

Do some tests to confirm this or not. And do check if there have been any firmware updates for that lens. Go to the Sony site and go to support for that lens. I see you say the A7R3 is up to date in updates. Not only is focusing at 5.6 difficult in dim light, but also if the subject has low contrast or dark tones.

You just might need to use modeling lights or brighter overall ambient lighting in your studio. I have 10 Godox/Flashpoint strobes and some do have modeling lights and focus assist beams which you can set to operate from some of the wireless triggers.

FYI I have owned A6500, A7RII, A7III, A7RIII and now own both A7RIV and A9, plus have pre-ordered the A7SIII. I have 13 E-mount lenses from 10mm to 600mm from Sony, Sigma, and Tamron. I am a professional of over 40+ years in the business. Formerly a Nikon and Canon user for decades and moved to Sony mirrorless back in January 2017 and have never regretted the move. Cheers

Wasabi

Have read (Friedman manuals) the the camera focuses poorly when the target is either horizontal lines or vertical, can't remember which. Don't know what your studio work is but you might consider it.

Frederick Weinald

BS

JJJLSN1 Loc: North Carolina

Thanks for your very good response to the Sony A7RIII question. Since you clearly know Sony, I would very much appreciate any help you might suggest re setup on my new Sony A7R4 for Birds in Flight Photography. My old Sony A7RII recently failed and I purchased my new A7R4 with the hope that my "hit rate" would be improved when photographing Osprey in flight. I use a Sony 100-400mm plus a 1.4 extender and have recently purchased a 2.0 extender but have not tried that yet. I also enjoy photographing other wildlife including bears and other birds. (I understand that the Sony A9 would be good for BIF but will not be purchasing that camera.

Toment Loc: FL, IL

You hijacking the OP’s thread. Please start your own thread. BTW welcome to a very helpful forum😄

gwilliams6

I will answer it anyway for those that might need some help.

Mark Smith's guide to setting up the A7RIV for BIF and other wildlife shooting

https://msmithphotos.com/index.php/2020/02/19/sony-a7riv-setup-guide-for-bird-in-flight-wildlife-photography/