lens advice

Mike Cash · 03-28-2009, 05:28 AM

S-M-C Takumar 28/3.5 from around forty years ago:

at f3.5

at f16

Similar vintage S-M-C Takumar 35/2:

at f2

at f5.6

Offered in response to the question about used lenses. The first pair offered to show that a lens needn't be blisteringly fast in order to enjoy the effect to some degree.

Marc Sabatella · 03-28-2009, 12:02 PM

Originally posted by Mike Cash

Offered in response to the question about used lenses. The first pair offered to show that a lens needn't be blisteringly fast in order to enjoy the effect to some degree.

Good demo! Sometime one gets the impression from reading about DOF that wide angle lenses have so much more of it that you wouldn't be able get that shallow look from a 28/3.5, but this shows otherwise. I find the same with my M28/2.8. Part of what happens, I think, is that in order to fill the frame with the main subject with a 28mm lens, you need to be closer to it than with a 50mm lens, thus changing the DOF equation.

alohadave · 03-28-2009, 12:39 PM

This is a pretty good explanation of how DoF and focal length work together.

DOF

DOF2

The first is a bit technical, but explains how DoF works. The second is a practical exercise that you can do yourself.

His Understanding Series and Essays are very good and cover a wide range of photographic subjects and techniques.

bsod · 06-05-2009, 12:18 AM

well lucky for me a friend had a 50 1.7 that he gave me it was a m42 so i had to buy an adapter no biggie, the camera store guy told me that i would have to do everything manually because of the adapter, fine but when i take photos it seems to take forever for the pic to take ? im guessing the shutter is very slow im not sure what i need to do any ideas ? i have the ring on the lens setting to 1.7

pentax ist dl yashica 50 mm 1.7 with adapter for this m42 lens

Marc Sabatella · 06-05-2009, 09:08 AM

Are you changing from AF to MF mode? If you are in AF mode, the camera won't shoot at all until it thinks you are in focus.

Otherwise, there should be no discernible difference in shooting speed between manual and other lenses.

06-05-2009, 12:18 AM	#19
bsod New Member Join Date: Mar 2009 Location: Taylorsville, Utah Photos: Gallery \| Albums Posts: 4 Original Poster	finally got a fast 50 well lucky for me a friend had a 50 1.7 that he gave me it was a m42 so i had to buy an adapter no biggie, the camera store guy told me that i would have to do everything manually because of the adapter, fine but when i take photos it seems to take forever for the pic to take ? im guessing the shutter is very slow im not sure what i need to do any ideas ? i have the ring on the lens setting to 1.7 pentax ist dl yashica 50 mm 1.7 with adapter for this m42 lens

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03-28-2009, 05:28 AM	#16
Mike Cash Veteran Member Join Date: Jan 2007 Location: Japan Photos: Gallery Posts: 6,950	S-M-C Takumar 28/3.5 from around forty years ago: at f3.5 at f16 Similar vintage S-M-C Takumar 35/2: at f2 at f5.6 Offered in response to the question about used lenses. The first pair offered to show that a lens needn't be blisteringly fast in order to enjoy the effect to some degree.

03-28-2009, 12:02 PM	#17
Marc Sabatella Veteran Member Join Date: Sep 2006 Location: Denver, CO Photos: Gallery Posts: 10,685	Originally posted by Mike Cash Offered in response to the question about used lenses. The first pair offered to show that a lens needn't be blisteringly fast in order to enjoy the effect to some degree. Good demo! Sometime one gets the impression from reading about DOF that wide angle lenses have so much more of it that you wouldn't be able get that shallow look from a 28/3.5, but this shows otherwise. I find the same with my M28/2.8. Part of what happens, I think, is that in order to fill the frame with the main subject with a 28mm lens, you need to be closer to it than with a 50mm lens, thus changing the DOF equation.

03-28-2009, 12:39 PM	#18
alohadave Veteran Member Join Date: Jan 2008 Location: Quincy, MA Photos: Gallery \| Albums Posts: 2,024	This is a pretty good explanation of how DoF and focal length work together. DOF DOF2 The first is a bit technical, but explains how DoF works. The second is a practical exercise that you can do yourself. His Understanding Series and Essays are very good and cover a wide range of photographic subjects and techniques.

06-05-2009, 09:08 AM	#20
Marc Sabatella Veteran Member Join Date: Sep 2006 Location: Denver, CO Photos: Gallery Posts: 10,685	Are you changing from AF to MF mode? If you are in AF mode, the camera won't shoot at all until it thinks you are in focus. Otherwise, there should be no discernible difference in shooting speed between manual and other lenses.