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Old Sep 3, 2008, 2:36 PM   #11
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and why manual focus?
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Old Sep 4, 2008, 4:19 AM   #12
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bernabeu wrote:
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the 1.4 is NOT worth 2-4 times the price of the 1.7

the 1.7 will be 70mm equivalent - perfect for indoor use

just remember - at f1.7 you have little to no DOF

try shooting iso 400 - f2.8-4 - 1/60s

MANUAL FOCUS !
The DOF will depend on the distance from the subject but yes it will be pretty narrow but unless you are only shooting someones head it will be deep enough. At f1.7 and 10' then you have a dof of almost 1' which will give nice isolation but more than enough in focus. Obviously this is not so good for group shots, but then neither is using a 50mm lens on a 1.5x crop unless you have a lot of space.

As for shooting at ISO 400, f2.8-4 and 1/60s there are not a lot of indoor, non flash situations where you have this much light. In the attached photo taken with a Canon 5D, 50mm f1.8 at f2, ISO 1250, 1/100s. So in the same lighting conditions if you were at f2.8 and ISO 400 you are going to be at about 1/15s. There were other parts of the room that day where the shutter was down to 1/30s at ISO 1250, f2.

Another thing you will notice and a reason for selecting this shotis the shadow under the eyes, this will depend on the lighting but can create some nasty results.

I have to ask, why MF?
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Old Sep 4, 2008, 7:32 AM   #13
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'...why MF?'

so you can get good focus on the eyes ... not the high contrast collar ... DOF

Last edited by bernabeu; Jun 27, 2015 at 4:25 PM.
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Old Sep 4, 2008, 7:56 AM   #14
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bernabeu wrote:
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'...why MF?'

so you can get good focus on the eyes ... not the high contrast collar ... DOF
I'm impressed if you can get a good focus without a focus screen, how do you ensure with a narrow aperture that you get it spot on? I've never managed so stick with AF.

What are you wanting to share in the photo as we are at f5.6, 35mm and flash was fired?

It does show how shadows under the eyes are removed, is this on-board or external flash, did you bounce it?
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Old Sep 4, 2008, 9:16 AM   #15
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I've seen optical experts comment on this issue before (use of manual focus on a camera without a better focus screen to assist), and the general consensus is that you're limited to around f/5.6 for consistent results with most entry level dSLR models like yours.

IOW, you just can't see enough difference in your subject's focus through the type of viewfinders you find in a camera model like yours to judge how an image is going to look at a larger viewing/print size when using wider apertures.

That's the same kind of thing you often run into reviewing photos on a camera's LCD. It may look nice and sharp at a smaller viewing size. Yet, when you look at a larger size on your PC's screen, you may go "oops... those were not in focus, or blurry").

Sure, if you carefully try to find the "mid point" using an AF ring at wider apertures, you may get it close enough to get some good shots, depending on the Depth of Field you have from your current focus distance. But, it tends to be a "hit and miss" kind of thing when DOF is very shallow.

Your camera model does have the ability to let you know when a subject is in focus using Manual Focus (still using the camera's AF sensors to judge it, versus what you see in your viewfinder) via a steady light if you rotate the focus ring while half pressing the shutter button). So, that may be useful so you can easily find the most accurate focus point if your subject is at the same distance from you. But, I wouldn't assume that because you see a sharp image in your viewfinder that's it's going to be sharp at a larger viewing size if you're using the image in the viewfinder to judge focus accuracy.

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Old Sep 17, 2008, 4:44 PM   #16
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'......................shadows under the eyes removed'

nope - no PS - the lady always wears sunglasses - that's tan lines



MF @ f1.7 - then shoot at desired settings

(turn command dial between A and P by touch/memory)



lol...how did AA ever manage to focus using only ground glass?

Last edited by bernabeu; Jun 27, 2015 at 4:25 PM.
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Old Sep 18, 2008, 12:00 AM   #17
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1. What model are you using?

2. If you cannot judge the focus of a shot or how it will appear 4x6..., then why ever use manual focus?

3. When in manual mode, what 'auto focus' feature would I use when half depressing the shutter button? I am using the Alpha 300.



Thanks
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