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Any way to speed up focus when vintage primes are on a7II?


Dian
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Sony a7II with a 200mm prime mounted.

Camera settings: A mode, ISO 200, multi metering, and auto shutter speed.

Aperture is set at f4.

Hand hold camera shooting Blue Magpies in mountains. Shooting distance is around 3 meters .  Very difficult to focus.

 

Any way to speed up focus in situations like this?

 

Thanks.

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Smaller aperture (higher f number) to increase depth of field, and to keep the shutter speed high enough, increase the ISO ... etc.

 

At F4 it can be more effective to prefocus and wait for subject to move into the right place.

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Smaller aperture (higher f number) to increase depth of field, and to keep the shutter speed high enough, increase the ISO ... etc.

 

At F4 it can be more effective to prefocus and wait for subject to move into the right place.

Thanks.

 

For 2 reasons that I use f4, to blur the background and to speed up the shutter.

Keep ISO at 100 or 200 to avoid noise.

 

Yes.  I have tried prefocus many, many times.  It works if I spend a whole morning for getting one shot in focus or not even one.  The depth of field of f4 of a 200mm lens focusing at around 3 meters is probably only 2 inches  or so (guessing).

 

I have seen friends do their tricks.  Prefocus the spot and fix the camera on tripod, and lure the birds to the spot by birds feed.

Yes.  They do get pretty good shots.  But I simply do not like the whole thing.

 

I am hoping maybe someone has thought of a method to speed up the focusing for the combination of mirrorless and vintage since there are so many of them out there.

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An A7II does not need to be throttled down to ISO 200.

That is self defeating. It's a given that you have set the

IBIS to match the FL, but a modern lens will also inform

the IBIS system of focus distance. Since you are shooting

at 3m instead of the typical 15 to 30m that the uninformed

IBIS system presumes to be typical for 200mm, you may

wanna jack the IBIS setting up to somewhere approaching

250mm +/-. 

  

Learn to see the difference in handheld shots where the

IBIS is set too high vs too low. Then you can find the best

IBIS setting for a 200mm at 3m distance by bracketed IBIS

testing. Too little IBIS will appear, as expected, somewhat

like any handheld shot at too low a shutter speed. With too

much IBIS specular highlights go streaky but not "soft". As

you back off the excess IBIS, the streaks get shorter.

 

You ask about focus but I tell you about IBIS ? Well, it you

haven't optimized your IBIS then you're forced to trade off

DOF to gain shutter speed. More DOF benefits focus, so

thaz why the talk about IBIS.

  

Or you could use a tripod. And practice your handholding.

It IS a motor skill, so practice will pay off. 

  

You'll need to raise your ISO. Raise it enuf to accomplish

two interrelated things. Primarily you gain shutter speed

or DOF. But you wanna "sacrifice" about 1/2 EV worth of

speed or DOF toward moving the histogram 1/2 EV to the

right. A left-leaning histogram results in increased noise. 

   

`

  

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Assuming you're shooting raw and that you have good eyesight, there is a neat trick that works especially well if the subject has enough micro-contrast, even in low-ish light.

 

Use "Vivid" as "Creative style" (it might work with other creative styles as well, but I find Vivid especially convenient for this trick), increasing contrast, saturation and sharpness to the max.

 

Now when an object is in focus it will show in the viewfinder with a noticeable "shivering pattern / moire" (it is the best I can define it, but it is fairly easy to see for yourself).

 

Take it like a sort of focus peaking, but while peaking at least with the A7r is pretty much always way off, even at its lowest setting, this gets you spot on focus or in the worst case almost spot on, but it is never way off. Compared to what used to be focusing on a ground glass, even on DSLRs, this is kid play ;)

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