Help Needed Understanding Exposure

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krishnandu

krishnandu

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Hello, I just got D5200 with default 18-55mm kit lens. I have gone through various tutorials for understanding Exposure Triangle. Today I was out for some testing same pic on various settings so that later I can review and get a practical idea. Now I'm stuck with very odd scenario.

Please look at the pics below with EXIF Data.

E2hUVse.jpg


1st : f22 1/60

oCrgzoa.jpg


2nd : f14 1/200

GbXEx6B.jpg


3rd : f9 1/500

PxC4CkS.jpg


4th : f3.5 1/3200

All the pics I have clicked on Aperture Priority Mode. So I set the aperture and camera decides Shutter Speed and ISO.

The problem is, small aperture (large f no) have high exposure and large aperture (small f no) have low exposure. Isn't it should be opposite? Large aperture means it's taking more light then how come it got low exposure instead of high exposure?

I do understand that the shutter speed have been changed by camera. But isn't that to maintain the balanced exposure? If so, then all the pics should have same exposure or with minor details.

But here the scenario is totally opposite. Large aperture images have low exposure and small aperture images have high exposure. How can this be possible?
 
I will tell you from the basic understanding of photography that I have.
Every camera has its own algorithm to calculate various settings based on inputs from its photometric sensors. In the various clicks that you have posted above, the aperture is gradually increasing thus decreasing the depth of field i.e. smaller area will remain in focus. As you can see in last image, the background is quite blurred compared to foreground. So based on the camera algorithm it has set the overall balance by exposing the foreground object (the guy in pic) a little more so that it looks clear while in earlier pics the exposure were decided based on the overall frame focus where in you have comparatively brighter things in background thus keeping the shutter speed high and balancing the exposure but in the last pics the focus is closer hence shutter has slowed down to get the required balance in frame.
 
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Channu said:
I will tell you from the basic understanding of photography that I have.
Every camera has its own algorithm to calculate various settings based on inputs from its photometric sensors. In the various clicks that you have posted above, the aperture is gradually increasing thus decreasing the depth of field i.e. smaller area will remain in focus. As you can see in last image, the background is quite blurred compared to foreground. So based on the camera algorithm it has set the overall balance by exposing the foreground object (the guy in pic) a little more so that it looks clear while in earlier pics the exposure were decided based on the overall frame focus where in you have comparatively brighter things in background thus keeping the shutter speed high and balancing the exposure but in the last pics the focus is closer hence shutter has slowed down to get the required balance in frame.
Click to expand...

Thanks a lot :)

Though I got more technical explanation here : http://photo.stackexchange.com/questions/70747/basic-exposure-query

Just thought of sharing the same, if someone wants to know the details.
 
Download the pdf version of "Understanding Exposure" by Bryan Peterson and thank me later.

If you need more book suggestions let me know.

U can find some really useful guides on digitalcameraworld.com highly recommended.
 
soumyajit92 said:
Download the pdf version of "Understanding Exposure" by Bryan Peterson and thank me later.

If you need more book suggestions let me know.

U can find some really useful guides on digitalcameraworld.com highly recommended.
Click to expand...

Thanks. I'd go through both of them. In the mean time, I think I'll shift to Manual Mode, so that I can control both looking at the EV Monitor. Need to play a lot :)
 
My suggestion would be to go through the theoritical before diving into any mode. Just study a bit, know more, for a few weeks. Then start with the camera that too not in manual mode. Start with semi manual modes i.e aperature priority and shutter priority modes and observe their relation to the kind of creativity you want out of ur photos. Then study aome more know different techniques, study composition post processing. My point is you need to know your shit before you get creative with your shit.
 
soumyajit92 said:
My suggestion would be to go through the theoritical before diving into any mode. Just study a bit, know more, for a few weeks. Then start with the camera that too not in manual mode. Start with semi manual modes i.e aperature priority and shutter priority modes and observe their relation to the kind of creativity you want out of ur photos. Then study aome more know different techniques, study composition post processing. My point is you need to know your shit before you get creative with your shit.
Click to expand...

Yeah. I understand. I didn't started using Manual Mode yet. Just playing with Aperture Priority.
 
Thanks to your query krishnandu , I fiddled a lot with my prosumer yesterday and brushed on all that was long forgotten ;)
 
krishnandu said:
That's great. I'm still playing with it to understand various concepts!!
Click to expand...
dude like i said you earlier on the group chat, check out the Foundations of Photography courses on Lynda.com by Ben Long.
This course got you covered on all the basic and intermediate stuffs about photography.
 
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@krishnandu To add to what @Channu said, you could try setting the metering to spot metering & then aim for the same spot to get more consistency vis-a-vis changes in the f-stop & resultant exposure. That's my noobish view of what's probably giving the weird results. If that is indeed the case, you are better off changing the metering mode & practicing with aperture or shutter priority before jumping to full manual. Hth.
 
@kidrow I clicked all the above in Aperture Priority mode only. That's why I thought Camera algo will take care of setting other parameters to achieve correct exposure. That's why I posted it here because it failed miserably.
 
krishnandu said:
@kidrow I clicked all the above in Aperture Priority mode only. That's why I thought Camera algo will take care of setting other parameters to achieve correct exposure. That's why I posted it here because it failed miserably.
Click to expand...
What was the metering mode set to? Try spot metering & then re-click with aperture priority.
 
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In your scenario, you are totally missing out on ISO. bigger the iso brighter the image. and you can see that the camera is increasing the iso to balance the shutter and aperture. Since your camera is in evaluative mode, the camera is bumping up iso. you should start using spot metering with Auto exposure lock button.

at the same time watch
and also download https://play.google.com/store/apps/details?id=com.dq.fotometro&hl=en to your android phone.
 
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