Comparing 50mm 1:1.7 to 18-55mm kit lens?

mojoe_24 · 01-11-2011, 05:29 PM

So I decided to spend some time with my dad's old 50mm 1:1.7 lens. I took a shot and the same shot with my kit lens to compare. I know the 50mm is supposed to be soft around the focus point, but is this overly blurry?

50mm:

18-55mm:

I haven't spent time with either lens really. Most of my pictures have been taken with the 50-200mm lens that came with my kit so sorry if this is kinda common sense.

eddie1960 · 01-11-2011, 05:36 PM

it's not soft it's the DOF from a wider aperture from the looks of it. the same thing that lets in more light narrows the depth of field significantly. Nice if you want out of focus backgrounds and isolating a subject .
a truer test would be to go out into good light and shoot the same thing with both at the same f stop. try shooting at say f4.0 - 4.5 which is about where the kit falls at the same focal length. the kit is at about it's best at 35-50 and f8.0 so try that as well
you should find the 50 resolves fine details better edge to edge, and for my money has a nicer colour rendition

then try shooting a contrasty subject at noon on a sunny day. the differnces will become more apparent.
the m 50 1.7 is sharper and resolves better when compared apples to apples
the above looks like the 50 @1.7 and the kit at 4.0 or
so

mojoe_24 · 01-11-2011, 05:48 PM

Yeah, I figured I should ahve used the same aperture once I hda the images uploaded, lol. I just mostly wanted to make sure that is how the lens should be. It hasn't been used in a several years.

eddie1960 · 01-11-2011, 06:05 PM

looks like it's bang on to me
it's one of my favourite lenses, but nailing the focus wide open is tough (easier than the 1.4 or a 1.2 though)

**Ash** · 01-11-2011, 06:35 PM

Understanding what depth of field is and you'll appreciate how the fast fifty will work for you.
The 50/1.7 is leagues above the kit lens in image quality, plus has the 'speed' advantage of over 3 stops of light at 50mm above the kit lens. It is well worth having.

fourfivesix · 01-12-2011, 10:54 AM

Ive been having the same problem with my smc a 50mm

eddie1960 · 01-12-2011, 11:01 AM

Originally posted by fourfivesix

Ive been having the same problem with my smc a 50mm

Re Read the above it's not an issue with the lens but with an understanding of how aperture affects the in focus area
wide open you will have a very small in focus area on a f1.4-f2.0 lens, (2.8 is not much better)

do a search for DOF or depth of field for a detailed explanation (there are likely at least a dozen on the forum alone

wiki

Depth of field - Wikipedia, the free encyclopedia

timh · 01-12-2011, 12:07 PM

It's ever so slightly soft, but you'll find that with pretty much every lens at a very wide aperture. It's very good though!

Most of what you're seeing is the very small slice of scenery that's in focus at f1.7 - example here (also showing what sharpening can do). Maan, I'm procrastinating today.

fourfivesix · 01-12-2011, 01:04 PM

Originally posted by fourfivesix

Ive been having the same problem with my smc a 50mm

Maybe I should have said my 50mm lens is having the same problem with me

**Ash** · 01-12-2011, 01:26 PM

Originally posted by fourfivesix

Maybe I should have said my 50mm lens is having the same problem with me

Like being flat at the best of times and soft and fuzzy in the corners?

01-11-2011, 05:29 PM	#1
mojoe_24 Senior Member Join Date: Nov 2010 Posts: 241	Comparing 50mm 1:1.7 to 18-55mm kit lens? So I decided to spend some time with my dad's old 50mm 1:1.7 lens. I took a shot and the same shot with my kit lens to compare. I know the 50mm is supposed to be soft around the focus point, but is this overly blurry? 50mm: 18-55mm: I haven't spent time with either lens really. Most of my pictures have been taken with the 50-200mm lens that came with my kit so sorry if this is kinda common sense.

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01-11-2011, 05:36 PM	#2
eddie1960 Veteran Member Join Date: Aug 2010 Location: Toronto Photos: Gallery \| Albums Posts: 13,666	it's not soft it's the DOF from a wider aperture from the looks of it. the same thing that lets in more light narrows the depth of field significantly. Nice if you want out of focus backgrounds and isolating a subject . a truer test would be to go out into good light and shoot the same thing with both at the same f stop. try shooting at say f4.0 - 4.5 which is about where the kit falls at the same focal length. the kit is at about it's best at 35-50 and f8.0 so try that as well you should find the 50 resolves fine details better edge to edge, and for my money has a nicer colour rendition then try shooting a contrasty subject at noon on a sunny day. the differnces will become more apparent. the m 50 1.7 is sharper and resolves better when compared apples to apples the above looks like the 50 @1.7 and the kit at 4.0 or so

01-11-2011, 05:48 PM	#3
mojoe_24 Senior Member Join Date: Nov 2010 Posts: 241 Original Poster	Yeah, I figured I should ahve used the same aperture once I hda the images uploaded, lol. I just mostly wanted to make sure that is how the lens should be. It hasn't been used in a several years.

01-11-2011, 06:05 PM	#4
eddie1960 Veteran Member Join Date: Aug 2010 Location: Toronto Photos: Gallery \| Albums Posts: 13,666	looks like it's bang on to me it's one of my favourite lenses, but nailing the focus wide open is tough (easier than the 1.4 or a 1.2 though)

01-11-2011, 06:35 PM	#5
Ash Loyal Site Supporter Join Date: Mar 2007 Location: Toowoomba, Queensland Photos: Gallery \| Albums Posts: 23,920	Understanding what depth of field is and you'll appreciate how the fast fifty will work for you. The 50/1.7 is leagues above the kit lens in image quality, plus has the 'speed' advantage of over 3 stops of light at 50mm above the kit lens. It is well worth having.

01-12-2011, 10:54 AM	#6
fourfivesix Inactive Account Join Date: Dec 2010 Location: Sheffield UK Posts: 61	Ive been having the same problem with my smc a 50mm

01-12-2011, 11:01 AM	#7
eddie1960 Veteran Member Join Date: Aug 2010 Location: Toronto Photos: Gallery \| Albums Posts: 13,666	Originally posted by fourfivesix Ive been having the same problem with my smc a 50mm Re Read the above it's not an issue with the lens but with an understanding of how aperture affects the in focus area wide open you will have a very small in focus area on a f1.4-f2.0 lens, (2.8 is not much better) do a search for DOF or depth of field for a detailed explanation (there are likely at least a dozen on the forum alone wiki Depth of field - Wikipedia, the free encyclopedia

01-12-2011, 12:07 PM	#8
timh Veteran Member Join Date: May 2010 Location: Wales Photos: Gallery \| Albums Posts: 445	It's ever so slightly soft, but you'll find that with pretty much every lens at a very wide aperture. It's very good though! Most of what you're seeing is the very small slice of scenery that's in focus at f1.7 - example here (also showing what sharpening can do). Maan, I'm procrastinating today.

01-12-2011, 01:04 PM	#9
fourfivesix Inactive Account Join Date: Dec 2010 Location: Sheffield UK Posts: 61	Originally posted by fourfivesix Ive been having the same problem with my smc a 50mm Maybe I should have said my 50mm lens is having the same problem with me

01-12-2011, 01:26 PM	#10
Ash Loyal Site Supporter Join Date: Mar 2007 Location: Toowoomba, Queensland Photos: Gallery \| Albums Posts: 23,920	Originally posted by fourfivesix Maybe I should have said my 50mm lens is having the same problem with me Like being flat at the best of times and soft and fuzzy in the corners?