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 EOS Digital Cameras 
Thread started 07 Sep 2011 (Wednesday) 16:25
Search threadPrev/next
sponsored links
(this ad will go away when you log in as a registered member)

Why don't modern DSLRs have split-screen or microprism areas?

 
paulkaye
Senior Member
Avatar
559 posts
Likes: 2
Joined Nov 2010
Location: Leamington, UK
     
Sep 07, 2011 16:25 |  #1

I appreciate that most lenses these days are auto-focus, but there are a good number of high quality manual focus specimens out there (including some from Canon themselves - such as the TS-E lenses). So, why is it that split focusing screens are available only as 3rd-party accessories?; and why have Canon arranged it so that if we use these things, we're likely to find that the metering system stops working properly?

Anyone who's used a split-screen or microprism on an old 35mm SLR will know how quick and easy they make manual focusing - it seems odd that it's so hard to get this facility on a modern DSLR - or am I just too old-fashioned?


Paul
_______________
5DII, 50mm 1.4, 17-40L, 85mm 1.8, 24-105L IS, 70-200L f4 IS, 100-400L, 100 f2.8 Macro
flickr (external link)

  
  LOG IN TO REPLY
sponsored links
(this ad will go away when you log in as a registered member)
picturecrazy
soft-hearted weenie-boy
Avatar
8,562 posts
Likes: 495
Joined Jan 2006
Location: Alberta, CANADA
     
Sep 07, 2011 16:38 |  #2

It's mostly because the AF system steals a LOT of the light coming in through the lens. The reflex mirror only partially reflects the image up into the viewfinder. The rest of the light goes downward to the AF sensors. Split prisms require a lot of light to work and steal a lot of light themselves too. Given that most of the light is already robbed, this makes the viewfinders too dark for general use, making split prisms only suitable with specialty lenses that are faster (i.e. F/2.8 or faster). Canon is not going to use a default screen that will NOT work well with many of their EF lens lineup.

Also, modern viewfinder sizes are painfully small compared to their manual focus predecessors, making the split prism centre themselves a lot smaller, and therefore, much harder to use.

Canon's priority is to make the viewfinders as bright as possible with the little amount of light that is left over.


-Lloyd
The BOUDOIR - Edmonton Intimate Boudoir Photography (external link)
Night and Day Photography - Edmonton Studio Family Baby Child Maternity Wedding Photographers (external link)
Night and Day Photography - Edmonton Headshot Photographers (external link)
Facebook (external link) | Twitter (external link) |Instagram (external link) | Gear

  
  LOG IN TO REPLY
Saint728
Goldmember
Avatar
2,892 posts
Likes: 1
Joined Jun 2009
Location: Honolulu Hawaii
     
Sep 07, 2011 16:40 |  #3

Canon does make split focus screens. I'm know they make one for the 1Ds Mark III and other bodies as well. www.google.com/url?sa=​t&source=web&cd=1&sqi=​2&ved=0CBYQFjAA&url=ht​tp%3A%2F%2Fwww.learn.u​sa.canon.com%2Fapp%2Fp​dfs%2Fquickguides%2FCD​LC_FocusingScreens_Qui​ckGuide.pdf&rct=j&q=ca​non%201ds%20mark%20III​%20split%20screen%20fo​cusing%20screens&ei=QO​RnTr6FHKTXiALKtJmUDQ&u​sg=AFQjCNEpa0e1bpA6D0W​zGlha-bTEVLV6fQ&cad=rja (external link)

Take Care,
Cheers, Patrick


Canon EOS 1Ds Mark III | 17-40mm f/4.0L | 70-200mm f/2.8L USM | 100mm f/2.8L IS Macro | 300mm f/4.0L IS
Click Here To See My Gear
Click here to see my Flickr (external link)
http://www.runryder.co​m/helicopter/gallery/9​019/ (external link)

  
  LOG IN TO REPLY
paulkaye
THREAD ­ STARTER
Senior Member
Avatar
559 posts
Likes: 2
Joined Nov 2010
Location: Leamington, UK
     
Sep 07, 2011 16:52 |  #4

picturecrazy wrote in post #13066009 (external link)
It's mostly because the AF system steals a LOT of the light coming in through the lens. The reflex mirror only partially reflects the image up into the viewfinder. The rest of the light goes downward to the AF sensors. Split prisms require a lot of light to work and steal a lot of light themselves too. Given that most of the light is already robbed, this makes the viewfinders too dark for general use, making split prisms only suitable with specialty lenses that are faster (i.e. F/2.8 or faster). Canon is not going to use a default screen that will NOT work well with many of their EF lens lineup.

Also, modern viewfinder sizes are painfully small compared to their manual focus predecessors, making the split prism centre themselves a lot smaller, and therefore, much harder to use.

Canon's priority is to make the viewfinders as bright as possible with the little amount of light that is left over.

Thanks for the insight. I knew the AF stole some light, but hadn't realised it was so much as to compromise the operation of a prism on the focusing screen.

I agree on the viewfinder size issue - I picked up an old OM-1 recently and was bowled over at the size of image in the finder (and the brightness now I think of it). Beautiful - if only my 5dii was that good.


Paul
_______________
5DII, 50mm 1.4, 17-40L, 85mm 1.8, 24-105L IS, 70-200L f4 IS, 100-400L, 100 f2.8 Macro
flickr (external link)

  
  LOG IN TO REPLY
Snafoo
Goldmember
Avatar
1,431 posts
Gallery: 92 photos
Best ofs: 2
Likes: 710
Joined Feb 2011
Location: Peculiar
     
Sep 07, 2011 18:56 |  #5

This thread is very Illuminating, if you'll pardon the pun. I love everything about digital over film, EXCEPT for the lack of a decent manual focus screen (on my 7D). I guess I was spoiled by my now ancient FTb, which despite its simplicity was a joy to look through.


http://www.jonstot.com​/ (external link)

  
  LOG IN TO REPLY
ZoneV
Goldmember
1,644 posts
Gallery: 5 photos
Best ofs: 1
Likes: 234
Joined Dec 2010
Location: Germany
     
Sep 08, 2011 01:51 |  #6

It is not that much light that goes away for the AF.
Seems to be 40% for the AF and 60% for the viewfinder with the EOS 5D classic.

I am working to get a 100% silver mirror into a EOS 5D, that will bring me some two thirds of an f-stop more light into the viewfinder.
The mirror is inside the camera at the moment, but only with tape. I need to test the EE-S focussing screen calibration, and have to shave the mirror frame (for the use with some manual lenses). And after that I suppose I will glue the mirror.

But it would be great, to have the split screen option, without paying high prices for it.
Will try this way to make a cheap split / microprism screen for my 5D (external link).


DIY-Homepage (external link) - Image Gallery (external link) - Gear List

  
  LOG IN TO REPLY
Keyan
Cream of the Crop
Avatar
5,319 posts
Gallery: 4 photos
Likes: 78
Joined Mar 2011
     
Sep 08, 2011 09:11 |  #7

Why not just use live view with the zoom on for manual focus (runs and hides from the incoming projectiles flung by the purists).


Cameras: 7D2, S100
Lenses: 17-55 f/2.8 IS USM, 18-135 STM, 24-70 f/4L IS USM, 50 f/1.4 USM,70-300L IS USM
Other Stuff: 430 EX II, Luma Labs Loop 3, CamRanger

  
  LOG IN TO REPLY
ToddR
Senior Member
Avatar
766 posts
Joined Feb 2009
Location: central Iowa
     
Sep 08, 2011 09:24 |  #8

I do occasionally miss the elegance of focusing my old AE-1 Program. Bringing a vertical line together in those two semicircles in the center of the viewfinder was pretty solid in its simplicity.


Gear List

  
  LOG IN TO REPLY
ZoneV
Goldmember
1,644 posts
Gallery: 5 photos
Best ofs: 1
Likes: 234
Joined Dec 2010
Location: Germany
     
Sep 08, 2011 10:10 |  #9

Keyan wrote in post #13069702 (external link)
Why not just use live view with the zoom on for manual focus ...

Liveview operation is much to slow for photographing my moving child with a fast lens.
Furthermore I do only have a 1000D as liveview camera, but like my two 5D much more.
With the optimized viewfinder I could see the hole image at once, and could focus my f/1.2 lenses wherever I want.
And such without problems with th sun shining on my back.


DIY-Homepage (external link) - Image Gallery (external link) - Gear List

  
  LOG IN TO REPLY
TeamSpeed
01010100 01010011
Avatar
36,162 posts
Gallery: 105 photos
Best ofs: 2
Likes: 5368
Joined May 2002
Location: Midwest
     
Sep 08, 2011 13:17 |  #10

picturecrazy wrote in post #13066009 (external link)
It's mostly because the AF system steals a LOT of the light coming in through the lens. The reflex mirror only partially reflects the image up into the viewfinder. The rest of the light goes downward to the AF sensors. Split prisms require a lot of light to work and steal a lot of light themselves too. Given that most of the light is already robbed, this makes the viewfinders too dark for general use, making split prisms only suitable with specialty lenses that are faster (i.e. F/2.8 or faster). Canon is not going to use a default screen that will NOT work well with many of their EF lens lineup.

Also, modern viewfinder sizes are painfully small compared to their manual focus predecessors, making the split prism centre themselves a lot smaller, and therefore, much harder to use.

Canon's priority is to make the viewfinders as bright as possible with the little amount of light that is left over.

I am not sure how split prism focusing screens relates to your reply, and I believe that there is now some confusion on the part of the OP. ???


Past Equipment | My Personal Gallery (external link) My Business Gallery (external link)
For Sale: Sigma USB Dock
For Sale: Ladies Thirty-One Camera Sling

  
  LOG IN TO REPLY
picturecrazy
soft-hearted weenie-boy
Avatar
8,562 posts
Likes: 495
Joined Jan 2006
Location: Alberta, CANADA
     
Sep 08, 2011 13:34 |  #11

TeamSpeed wrote in post #13070871 (external link)
I am not sure how split prism focusing screens relates to your reply, and I believe that there is now some confusion on the part of the OP. ???

I think your statement is the most confusing one in this thread?? He asked why modern dslrs don't have split prisms by default. I told them it all requires lots of light and good size to be effective. Installing a split prism will darken the viewfinder. Canon's priority is to make the viewfinder as bright as possible to work well with ALL EF lenses. Hence, no split prisms by default in modern dslrs. How does that not have anything to do with the original question? The OP's response was "thanks for the insight". What part of that says the OP is confused? You're the one who has ME confused??


-Lloyd
The BOUDOIR - Edmonton Intimate Boudoir Photography (external link)
Night and Day Photography - Edmonton Studio Family Baby Child Maternity Wedding Photographers (external link)
Night and Day Photography - Edmonton Headshot Photographers (external link)
Facebook (external link) | Twitter (external link) |Instagram (external link) | Gear

  
  LOG IN TO REPLY
Bruce ­ Foreman
Senior Member
Avatar
279 posts
Likes: 2
Joined Jul 2004
Location: San Angelo, Texas
     
Sep 08, 2011 13:34 as a reply to  @ TeamSpeed's post |  #12

Split prism and microprism focusing aids require a lot of light to work with. Even with the older cameras with bright viewfinders if you stopped your lens down with the DOF prevue button pressed, one side of the little "prism" would go dark. Some longer lenses with a maximum aperture of f5.6 or smaller would cause that to happen without the DOF prevue button pressed.

With one side of the split image focusing aid or one side of each microprism going dark, the "aid" could not be used and focus had to be judged on the screen itself.

The current generation of first time DSLR purchasers, dependent on autofocus, could not deal with darkening microprism "grid" or split image with half of it going dark.




  
  LOG IN TO REPLY
paulkaye
THREAD ­ STARTER
Senior Member
Avatar
559 posts
Likes: 2
Joined Nov 2010
Location: Leamington, UK
     
Sep 08, 2011 13:44 |  #13

TeamSpeed wrote in post #13070871 (external link)
I am not sure how split prism focusing screens relates to your reply, and I believe that there is now some confusion on the part of the OP. ???

No - not too confused really!! I've learnt that the AF steals about 40% of the light going to the viewfinder and that means that split-screen focusing aids don't work too well with slower lenses. That's probably a good reason why Canon has ditched them - except as an option on the 1D line.

It's also true though that the finders on modern DSLRs are small compared to those on old 35mm SLRs - I can only assume that Canon (and other manufacturers) believe that we don't need such luxury in the age of AF - which is a shame :cry: If anyone has an OM-1 hanging around - go take a look in the finder. It's quite an experience if you've been using an xxxD/Rebel or xxD - or even an xD.


Paul
_______________
5DII, 50mm 1.4, 17-40L, 85mm 1.8, 24-105L IS, 70-200L f4 IS, 100-400L, 100 f2.8 Macro
flickr (external link)

  
  LOG IN TO REPLY
Kevan
Goldmember
Avatar
3,123 posts
Likes: 13
Joined Dec 2007
Location: Easton, MD
     
Sep 08, 2011 13:49 |  #14

New to the dslr scene, I'm a bit surprised how often I've taken my lens off AF for better tweaking. Boy, do I miss the ol' split screen daze.


kevan's lens (external link)

  
  LOG IN TO REPLY
a1ex
Member
177 posts
Joined Aug 2011
     
Sep 08, 2011 14:15 |  #15

They have split screen, with Magic Lantern in LiveView :)

(digital split screen, not optical)


[auto ettr] (external link) [raw video] (external link) [holy grail] (external link) [changelog] (external link)

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

12,025 views & 0 likes for this thread
Why don't modern DSLRs have split-screen or microprism areas?
FORUMS Canon Cameras, Lenses & Accessories Canon EOS Digital Cameras 
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 Rooster7
989 guests, 315 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.