New lens

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Duncan Holmes
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New lens

Post by Duncan Holmes »

After waiting an age for a decent deal on a Sony e mount prime, I took the plunge at the weekend and purchased A new 28mm f2, which I am told on my Sony aps-c sensor will give me around 42mm focal length.

Played around at the weekend in the garden and then woods, am am delighted in the reduction in dof that I can get, but stopping it down all the way seams like it will be too shallow for fish portraits.

At say iso400, with a prime lens, what is people's go to stop number for portraits?
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davelumb
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Re: New lens

Post by davelumb »

I don't understand why stopping it down will not give you enough depth of field. The more you stop a lens down the greater the DoF becomes. :scratch: Prime or zoom makes no odds, it's aperture, focal length and distance from subject which affects DoF. (And if being pedantic image size and distance when looking at the picture too!)

I'd have thought f5.6 would be adequate with that set up for trophy shots.
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Re: New lens

Post by Duncan Holmes »

davelumb wrote: Mon Aug 06 2018 21:19 -
I don't understand why stopping it down will not give you enough depth of field. The more you stop a lens down the greater the DoF becomes. :scratch: Prime or zoom makes no odds, it's aperture, focal length and distance from subject which affects DoF. (And if being pedantic image size and distance when looking at the picture too!)

I'd have thought f5.6 would be adequate with that set up for trophy shots.
Maybe I got my up and down mixed up :red:

I meant lower number when I said down.

I love the blurred background look that makes the subject pop out of the photo. My package lens didn't really give me the level of background blur that I wanted. This lens does, but I thought I was going to need to go low numbers to get the effect, but it looks like I don't need to go as low as I thought.

6 ft seams about right with framing for trophy shot,
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Re: New lens

Post by davelumb »

Stopping down means making the aperture smaller. The the smaller the f number the bigger the aperture and the more the DoF. So you would stop down from f4 to f8.

The smaller the f number the larger the aperture and the less the DoF.

It can be confusing.

Camera to subject distance should really be defined by how you want to frame the shot. With a fixed focal length you're a bit limited in that respect.
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Re: New lens

Post by davelumb »

Rethink. I forgot it's an APS sensor, so f2.8 to f4 might be a better bet to get fish and angler oth reasonably sharp and the background blurred. But as I said, how far the background is behind the angler makes a difference.
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Re: New lens

Post by Duncan Holmes »

davelumb wrote: Mon Aug 06 2018 21:46 -
Stopping down means making the aperture smaller. The the smaller the f number the bigger the aperture and the more the DoF. So you would stop down from f4 to f8.

The smaller the f number the larger the aperture and the less the DoF.

It can be confusing.

Camera to subject distance should really be defined by how you want to frame the shot. With a fixed focal length you're a bit limited in that respect.
Thanks, knew the smaller number was bigger hole, but know know the up and down terminology :thumbs:

Certainly noticed the difference framing over the zoom, can't remember the last time I had a fixed lens, probably on an old ae1 program 30 years ago.

Also learned how to manual focus the camera at the weekend, using the focus zoom.

Tbh the camera has always taken nice photos, but it was quite fun learning how to make the camera do what you want rather than rely on P or I settings.
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Re: New lens

Post by davelumb »

:thumbs:

Just to show that a small aperture isn't all there is to shallow DoF this was taken with a 50mm on full frame at f4. And there isn't much in focus. :grin:

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Re: New lens

Post by cookiesdaughtersdad »

:grin: :wink:

Cheeers Alan
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