Approve the Cookies
This website uses cookies to improve your user experience. By using this site, you agree to our use of cookies and our Privacy Policy.
OK
Index  •   • New posts  •   • RTAT  •   • 'Best of'  •   • Gallery  •   • Gear  •   • Reviews
Guest
New posts  •   • RTAT  •   • 'Best of'  •   • Gallery  •   • Gear  •   • Reviews
Register to forums    Log in

 
FORUMS Canon Cameras, Lenses & Accessories Canon EF and EF-S Lenses 
Thread started 10 Aug 2014 (Sunday) 17:11
Search threadPrev/next
sponsored links
(this ad will go away when you log in as a registered member)

Sigma 70 mm f2.8 EX DG -vs- Canon 85mm f1.8

 
Ralph ­ III
Goldmember
1,345 posts
Likes: 16
Joined Mar 2009
Location: Alabama
     
Aug 10, 2014 17:11 |  #1

Hello,
Does or has anyone ever used the Sigma for portrait work? I have a Canon 85mm f1.8 for portraits but wondered how the Sigma would compare given it also has 1:1 Macro ability? I think the 70mm might suit me better for indoors as well.

I realize the focus speed of the Canon is superior but I'm more interested in the background blur and bokeh comparison.

Thanks,
Ralph


"SOUTHERN and SAVED!"
POTN FEEDBACK...............ITEMS FOR SALE

  
  LOG IN TO REPLY
sponsored links
(this ad will go away when you log in as a registered member)
pulsar123
Goldmember
2,140 posts
Gallery: 67 photos
Best ofs: 1
Likes: 475
Joined Apr 2010
Location: Canada
     
Aug 10, 2014 19:52 |  #2

The background blur of the 70mm lens is 85mm/1.8/(70mm/2.8)=1.​9x smaller than for the 85mm lens, because of the smaller aperture. It is even smaller than for nifty-fifty, so don't expect much of a blur.


6D, Tamron 24-70 f2.8 VC, 135L, 70-200 f4L, Laowa 15mm 1:1 macro, 50mm f1.8 STM, Samyang 8mm fisheye, home studio

  
  LOG IN TO REPLY
runninmann
what the heck do I know?
Avatar
8,156 posts
Gallery: 47 photos
Likes: 150
Joined Feb 2006
Location: Michigan-U.S.A.
     
Aug 10, 2014 20:02 |  #3

Do you plan to shoot your portraits at f/1.8 or f/2.8? Will you position the portrait subject the same distance from the camera and background?

If you shoot at, let's say 5.6, or at any aperture common to both lenses, you can affect the DOF by adjusting distances.


My Gear

  
  LOG IN TO REPLY
Reservoir ­ Dog
A Band Apart
Avatar
3,279 posts
Gallery: 469 photos
Best ofs: 9
Likes: 435
Joined Jan 2013
Location: Out of the pack
     
Aug 10, 2014 20:43 |  #4

Ralph III wrote in post #17087931 (external link)
I realize the focus speed of the Canon is superior but I'm more interested in the background blur and bokeh comparison.

Thanks,
Ralph

If you are more interested in the background blur and bokeh comparison go for the Sigma 85mm f/1.4 EX
it's a tack sharp lens already at f/1.4 (no need to stop down to get sharp), very accurate and fast AF and a very nice Bokeh


150 Free online photos editing application (external link) / 100 Free Desktop Photo Editor Software (external link) / Free Photography eBooks (external link) / My photography blog (external link)

  
  LOG IN TO REPLY
Ralph ­ III
THREAD ­ STARTER
Goldmember
1,345 posts
Likes: 16
Joined Mar 2009
Location: Alabama
     
Aug 10, 2014 21:26 as a reply to  @ Reservoir Dog's post |  #5

Thanks for the replies.

The Sigma 85mm f1.8 is a $700.00 lens so I'm not considering that. I was really curious as to how the Sigma 70mm f2.8 performs as a Portrait lens? I'm assuming some f2.8 lenses will perform better with background blur and bokeh than others having had the Tamron 28-75mm f2.8?

As it is, I will most likely shoot at f2.0 or f2.2 with the Canon 85mm f1.8 because color fringing is less pronounced (versus f1.8) and yet you still maintain excellent background blur (separation). I just got the lens so that is my initial findings. I'm not looking to shoot individual portraits at anything higher than f2.8.

Thanks,
Ralph


"SOUTHERN and SAVED!"
POTN FEEDBACK...............ITEMS FOR SALE

  
  LOG IN TO REPLY
MalVeauX
"Looks rough and well used"
Avatar
13,339 posts
Gallery: 1716 photos
Best ofs: 4
Likes: 10793
Joined Feb 2013
Location: Florida
     
Aug 11, 2014 00:35 |  #6

Ralph III wrote in post #17087931 (external link)
Hello,
Does or has anyone ever used the Sigma for portrait work? I have a Canon 85mm f1.8 for portraits but wondered how the Sigma would compare given it also has 1:1 Macro ability? I think the 70mm might suit me better for indoors as well.

I realize the focus speed of the Canon is superior but I'm more interested in the background blur and bokeh comparison.

Thanks,
Ralph

Heya,

You're comparing F1.8 and F2.8 and saying you want more background blur? You're going to get less.

Do you need macro ability for this?

If you're doing it indoors and you don't have enough space and 85mm is too long, just look at a good copy of a Sigma 50mm F1.4, or even a Canon 35 F2 IS.

Very best,


My Flickr (external link) :: My Astrobin (external link)

  
  LOG IN TO REPLY
GeoKras1989
Goldmember
Avatar
4,038 posts
Gallery: 2 photos
Likes: 261
Joined Jun 2014
     
Aug 11, 2014 07:38 |  #7
bannedPermanent ban

pulsar123 wrote in post #17088148 (external link)
The background blur of the 70mm lens is 85mm/1.8/(70mm/2.8)=1.​9x smaller than for the 85mm lens, because of the smaller aperture. It is even smaller than for nifty-fifty, so don't expect much of a blur.

I am struggling with the math here. If something is one-times smaller than something else, it has ceased to exist. How is it even possible to be 1.9x smaller?

A dinner plate may be 10" in diameter. One times 10" = 10". If the second plate is one times (10") smaller (10"-10" - 0"), it already doesn't exist. How can it possibly get to 1.9x smaller?

Seems like weird multi-dimensional Star Trek math to me.


WARNING: I often dispense advice in fields I know little about!

  
  LOG IN TO REPLY
raptor3x
Senior Member
Avatar
728 posts
Gallery: 5 photos
Likes: 78
Joined Aug 2011
Location: Rutland, VT
     
Aug 11, 2014 08:55 |  #8

GeoKras1989 wrote in post #17088860 (external link)
I am struggling with the math here. If something is one-times smaller than something else, it has ceased to exist. How is it even possible to be 1.9x smaller?

A dinner plate may be 10" in diameter. One times 10" = 10". If the second plate is one times (10") smaller (10"-10" - 0"), it already doesn't exist. How can it possibly get to 1.9x smaller?

Seems like weird multi-dimensional Star Trek math to me.

1.9x smaller denotes a multiplier of 1/1.9. If something is one times smaller then it is the same size.


Bodies: X-T1, E-M1ii, G9 Lenses: µ.Z 7-14 2.8, µ.Z 12-40 2.8, µ.Z 25 1.2, X 18-55 2.8-4, µ.Z 40-150 2.8, µ.Z 45 1.2, µ.Z 60 2.8, µ.Z 75 1.8, PL 200 2.8

  
  LOG IN TO REPLY
GeoKras1989
Goldmember
Avatar
4,038 posts
Gallery: 2 photos
Likes: 261
Joined Jun 2014
     
Aug 11, 2014 09:21 |  #9
bannedPermanent ban

raptor3x wrote in post #17088938 (external link)
1.9x smaller denotes a multiplier of 1/1.9. If something is one times smaller then it is the same size.

That makes no sense. If I give you one times $10, I have given you $10. If I give you 2 times $10 I have give you $20. If I give you 0.5 times $10, I have given you $5.

The entire point of communication is understanding. Your math indicates that you mean 0.526x. Calling it 1.9X smaller is just weird.


WARNING: I often dispense advice in fields I know little about!

  
  LOG IN TO REPLY
pulsar123
Goldmember
2,140 posts
Gallery: 67 photos
Best ofs: 1
Likes: 475
Joined Apr 2010
Location: Canada
     
Aug 11, 2014 10:20 |  #10

0.526x larger or 1.9x smaller - same thing.

I should have expressed myself as "the Canon will produce background blur 1.9x stronger than the Sigma".


6D, Tamron 24-70 f2.8 VC, 135L, 70-200 f4L, Laowa 15mm 1:1 macro, 50mm f1.8 STM, Samyang 8mm fisheye, home studio

  
  LOG IN TO REPLY
GeoKras1989
Goldmember
Avatar
4,038 posts
Gallery: 2 photos
Likes: 261
Joined Jun 2014
     
Aug 11, 2014 10:22 |  #11
bannedPermanent ban

pulsar123 wrote in post #17089080 (external link)
0.526x larger or 1.9x smaller - same thing.

I should have expressed myself as "the Canon will produce background blur 1.9x stronger than the Sigma".

Not if you are trying to communicate with someone reasonably literate with numbers.

At least that would be true. Your original statement isn't even physically possible.


WARNING: I often dispense advice in fields I know little about!

  
  LOG IN TO REPLY
agedbriar
Goldmember
Avatar
2,622 posts
Likes: 352
Joined Jan 2007
Location: Slovenia
     
Aug 11, 2014 15:39 |  #12

VWDOF has all the answers. Downloadable and free.

http://toothwalker.org​/optics/vwdof.html (external link)

.


HOSTED PHOTO
please log in to view hosted photos in full size.




  
  LOG IN TO REPLY
FEChariot
Goldmember
Avatar
4,423 posts
Gallery: 13 photos
Likes: 345
Joined Sep 2011
     
Aug 11, 2014 16:46 as a reply to  @ agedbriar's post |  #13

Wow Reciprocals 101


Canon 7D/350D, Σ17-50/2.8 OS, 18-55IS, 24-105/4 L IS, Σ30/1.4 EX, 50/1.8, C50/1.4, 55-250IS, 60/2.8, 70-200/4 L IS, 85/1.8, 100/2.8 IS L, 135/2 L 580EX II, 430EX II * 2, 270EX II.

  
  LOG IN TO REPLY
Reservoir ­ Dog
A Band Apart
Avatar
3,279 posts
Gallery: 469 photos
Best ofs: 9
Likes: 435
Joined Jan 2013
Location: Out of the pack
     
Aug 11, 2014 18:56 |  #14

agedbriar wrote in post #17089659 (external link)
VWDOF has all the answers. Downloadable and free.

http://toothwalker.org​/optics/vwdof.html (external link)

.

do they have for Mac ? (didn't find it)


150 Free online photos editing application (external link) / 100 Free Desktop Photo Editor Software (external link) / Free Photography eBooks (external link) / My photography blog (external link)

  
  LOG IN TO REPLY
agedbriar
Goldmember
Avatar
2,622 posts
Likes: 352
Joined Jan 2007
Location: Slovenia
     
Aug 12, 2014 02:53 |  #15

Seems not, unfortunately...




  
  LOG IN TO REPLY
sponsored links
(this ad will go away when you log in as a registered member)

1,660 views & 0 likes for this thread
Sigma 70 mm f2.8 EX DG -vs- Canon 85mm f1.8
FORUMS Canon Cameras, Lenses & Accessories Canon EF and EF-S Lenses 
AAA
x 1600
y 1600

Jump to forum...   •  Rules   •  Index   •  New posts   •  RTAT   •  'Best of'   •  Gallery   •  Gear   •  Reviews   •  Member list   •  Polls   •  Image rules   •  Search   •  Password reset

Not a member yet?
Register to forums
Registered members may log in to forums and access all the features: full search, image upload, follow forums, own gear list and ratings, likes, more forums, private messaging, thread follow, notifications, own gallery, all settings, view hosted photos, own reviews, see more and do more... and all is free. Don't be a stranger - register now and start posting!


COOKIES DISCLAIMER: This website uses cookies to improve your user experience. By using this site, you agree to our use of cookies and to our privacy policy.
Privacy policy and cookie usage info.


POWERED BY AMASS forum software 2.1forum software
version 2.1 /
code and design
by Pekka Saarinen ©
for photography-on-the.net

Latest registered member is heflerbj
876 guests, 294 members online
Simultaneous users record so far is 15144, that happened on Nov 22, 2018

Photography-on-the.net Digital Photography Forums is the website for photographers and all who love great photos, camera and post processing techniques, gear talk, discussion and sharing. Professionals, hobbyists, newbies and those who don't even own a camera -- all are welcome regardless of skill, favourite brand, gear, gender or age. Registering and usage is free.