Ruined

EOS R
Aug 22, 2013
930
59
I agree completely, although to be fair to the current group of users, back then you had split prisms etc. that made focusing pretty equal to the electronic focus aides of today. It's frustrating that you can no longer change focusing screens on modern DSLRs
I have a 6D with a Eg-S high precision screen . It is great when needing to manual focus fast lenses, but when using autofocus it doesn't offer too much advantage over a typical focusing screen. Yeah you can get a better idea of what wide open looks like on a fast lens, but experience will generally inform you what aperture to set anyway in a given situation. As I don't believe Canon has any manual EF lenses in production faster than f/2.8 they probably considered it a safe bet to eliminate the swapping feature. They don't want you to buy competitor manual only lenses anyway.
 

CanonFanBoy

Purple
CR Pro
Jan 28, 2015
5,628
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I have a 6D with a Eg-S high precision screen . It is great when needing to manual focus, but when using autofocus it doesn't offer too much advantage over a typical focusing screen. Yeah you can get a better idea of what wide open looks like on a fast lens, but experience will generally inform you what aperture to set anyway in a given situation. As I don't believe Canon has any manual EF lenses faster than f/2.8 they probably considered it a safe bet to eliminate the swapping feature.
Would any focusing screen offer any advantage when in AF?
 

Ruined

EOS R
Aug 22, 2013
930
59
Would any focusing screen offer any advantage when in AF?
Sure. The stock focusing screens minimum DOF displayed is in the ballpark of f/2.8. so if you use an f/1.2 lens and lock AF through the viewfinder you won't see the true DOF wide open on the stock screen, instead you will see more in focus than actually is. With high precision screen you will see closer to the real f/1.2 DOF, but the tradeoff is that it is significantly dimmer - which is why they use the brighter but less accurate screen in the first place.

So the advantage is the high precision screens are more WYSIWYG with fast lenses wide open once focus is attained (AF or otherwise). But that advantage is not a huge one with autofocus if you have experience knowing what to expect with the lens wide open in terms of DOF
 
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Ruined

EOS R
Aug 22, 2013
930
59
The AF module is independent and has no connection to the focusing screen.
The AF module acquires focus.

The focus screen displays what is focused

The stock focusing screen is only accurate in the viewfinder to a minimum DOF of around f/2.8

The EG-S high precision screen on the other hand can display the thin DOF of lenses faster than f/2.8 in the viewfinder unlike the stock screen - at the expense of brightness.

Therefore, while the focus screen does not affect the AF acquiring targets, it does affect the accuracy of what you see in the viewfinder as being in focus - and it does not matter if that focus was attained via AF or manual. Thus, it is a big advantage for MF and a small advantage for AF with fast lenses. Because even if you acquired focus with AF, if using f/1.2 lens you will get a surprise when less is in focus than you thought with the actual picture vs what you saw in the viewfinder w/ stock screen.
 
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Sporgon

5% of gear used 95% of the time
CR Pro
The AF module acquires focus.

The focus screen displays what is focused

The stock focusing screen is only accurate in the viewfinder to a minimum DOF of around f/2.8

The EG-S high precision screen on the other hand can display the thin DOF of lenses faster than f/2.8 in the viewfinder unlike the stock screen - at the expense of brightness.

Therefore, while the focus screen does not affect the AF acquiring targets, it does affect the accuracy of what you see in the viewfinder as being in focus - and it does not matter if that focus was attained via AF or manual. Thus, it is a big advantage for MF and a small advantage for AF with fast lenses. Because even if you acquired focus with AF, if using f/1.2 lens you will get a surprise when less is in focus than you thought with the actual picture vs what you saw in the viewfinder w/ stock screen.
No. Being able to see the difference in the critical point of focus between say f/1.2 and f/1.8 is impossible with the naked eye when viewed on a small ground glass screen, let alone a cheap plastic one. To do this you’d have to magnify - just as we do now with EVF or live view to get critically accurate focus. Also adding translucent lcd and diopter adjustment that you are looking through all add to the loss of accuracy.
 

Ruined

EOS R
Aug 22, 2013
930
59
No. Being able to see the difference in the critical point of focus between say f/1.2 and f/1.8 is impossible with the naked eye when viewed on a small ground glass screen, let alone a cheap plastic one. To do this you’d have to magnify - just as we do now with EVF or live view to get critically accurate focus. Also adding translucent lcd and diopter adjustment that you are looking through all add to the loss of accuracy.
I didn't say "the critical point of focus." I said being able to see the difference of what is in focus in the slim DOF of a fast lens. In fact, that is why the Eg-S screen exists in the first place, and being able to more accurately determine the DOF of fast lenses is exactly how it makes manual focusing easier. But this advantage does not end at manual focus, because that aid also helps reveal what is in focus in the DOF from something you AF'd in a fast lens.
 

Sporgon

5% of gear used 95% of the time
CR Pro
I didn't say "the critical point of focus." I said being able to see the difference of what is in focus in the slim DOF of a fast lens. In fact, that is why the Eg-S screen exists in the first place, and being able to more accurately determine the DOF of fast lenses is exactly how it makes manual focusing easier. But this advantage does not end at manual focus, because that aid also helps reveal what is in focus in the DOF from something you AF'd in a fast lens.
Yes I appreciate what you are saying, but from my experience with the Eg-S screens I disagree. As I always used relatively fast lenses, or I suppose more correctly don't use slow lenses, in my days of using the original 5D and then 5DII and 6D I always had the Eg-S screens fitted as there wasn't the downside of having a darker than usual viewfinder with f/4 and slower lenses. As you say, seeing more of a true rendering of the actual dof was beneficial, but in terms of assessing whether the AF had hit the mark with a f/1.2 or f/2 lens it doesn't help one jot. The margin of error is just too small to see in this way. So for assistance in manual focusing fast lenses, and seeing a truer representation of the real dof, yes the Eg-S screens are great, but in terms of helping the photographer see if the AF has hit the mark 100% with a fast lens, not so much.

I'm guessing that after Canon introduced the 5DIII with its much more sophisticated AF system, they thought there wasn't much call for manually focusing as an override. One of the decisions I find strange though is that while the 7D didn't have an interchangeable screen the 7DII did. I wouldn't have thought that this was a camera that people would be clamouring to change the screens.
 

Ruined

EOS R
Aug 22, 2013
930
59
Yes I appreciate what you are saying, but from my experience with the Eg-S screens I disagree. As I always used relatively fast lenses, or I suppose more correctly don't use slow lenses, in my days of using the original 5D and then 5DII and 6D I always had the Eg-S screens fitted as there wasn't the downside of having a darker than usual viewfinder with f/4 and slower lenses. As you say, seeing more of a true rendering of the actual dof was beneficial, but in terms of assessing whether the AF had hit the mark with a f/1.2 or f/2 lens it doesn't help one jot. The margin of error is just too small to see in this way. So for assistance in manual focusing fast lenses, and seeing a truer representation of the real dof, yes the Eg-S screens are great, but in terms of helping the photographer see if the AF has hit the mark 100% with a fast lens, not so much.

I'm guessing that after Canon introduced the 5DIII with its much more sophisticated AF system, they thought there wasn't much call for manually focusing as an override.
I basically agree with you, if you note way above I originally stated that the Eg-S screen isn't so useful for AF and that is likely why they stopped offering the interchangeable screens. But in select cases it does have *some* small advantage in that you get more of a WYSIWYG experience with DOF on fast lenses (both MF&AF), not so much if you definitely nailed focus but a better idea of how slim the DOF is. And that is what I was trying to communicate to the poster who asked if it had *any* advantages over a stock screen.

i believe the fastest MF-only lens in the Canon lineup is f/2.8 so they probably felt the disadvantages outweighed the advantages
 
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Michael Clark

Now we see through a glass, darkly...
Apr 5, 2016
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I agree completely, although to be fair to the current group of users, back then you had split prisms etc. that made focusing pretty equal to the electronic focus aides of today. It's frustrating that you can no longer change focusing screens on modern DSLRs

We also had much longer throws of the focus ring for the same amount of focus movement that made fine focusing movements easier. I probably had better fine motor skills back then, too. and I KNOW I had better closeup vision to see the rear LCD with than even half a decade ago. Now, if I even breath while touching the focusing ring of modern AF lenses I'll totally lose precise focus for astro work.
 
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Del Paso

M3 Singlestroke
Aug 9, 2018
1,238
1,312
I agree completely, although to be fair to the current group of users, back then you had split prisms etc. that made focusing pretty equal to the electronic focus aides of today. It's frustrating that you can no longer change focusing screens on modern DSLRs
Even though I agree on the subject of interchangeability of focusing screens, I never understood how one could achieve a precise focus with microprisms or split prisms. They were pretty useless (for me !) since darkening with tele or macro lenses, also with less luminous ones. But a full-matte screen was my choice.I even went so far as to replace myself the microprism screen on my Leicaflexes, which meant removing the top-cover, the prism etc... Much easier on the R4, 5, 6 and 7...
I also replaced the screen on the 5D III, but replaced it afterwards with the original one since wasn't convinced of any advantage.
 

GMCPhotographics

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CR Pro
Aug 22, 2010
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www.GMCPhotographics.co.uk
Even though I agree on the subject of interchangeability of focusing screens, I never understood how one could achieve a precise focus with microprisms or split prisms. They were pretty useless (for me !) since darkening with tele or macro lenses, also with less luminous ones. But a full-matte screen was my choice.I even went so far as to replace myself the microprism screen on my Leicaflexes, which meant removing the top-cover, the prism etc... Much easier on the R4, 5, 6 and 7...
I also replaced the screen on the 5D III, but replaced it afterwards with the original one since wasn't convinced of any advantage.
It really depends on light levels and the brightness of the lens, As a wedding photographer using a pair of 5DmkII's (back in the day) with the fine focus screen was a blessing. I could actually see my 85mm f1.2 focus very precisely. I could also focus the lens and recompose while checking the point of focus was spot on. The default / stock "brighter" view finder is Depth of Field limited to f4 with the optical view finder. For a 70-200 f2.8 that's not too much of a stretch....however My typical pairing was a 35mm f1.4L and 85mm f1.2 and the stock view finder was pretty hopeless. Thankfully on the 5DmkIII, the single point AF is very accurate. It was a bit of a skills transition to trust that the 5DmkIII's AF nailed the point of focus with out the visual check. Sometimes, I would use the live view focus...just to make sure.

I think the transition to Mirrorless cameras is going to be a slow process. The technology is getting better and better with each generation and this path sort of started with the introduction of live view, way back. Mirrorless has to be able to offer clear and distinct advantages over the DSLR and it's optical view finder. Power usage is a serious concern. Mirrorless cameras use a lot more power and are more power reliant. Canon have also been holding back innovation and tech on their DSLR range for some time...waiting for their drop on the RF bodies. Focussing down to -8 ev is a massive boon for some photographers. Seeing what you get in the view finder is another. However the View finder flicker, delay and heavy viewfinder contrast can be off putting. Low light EVF noise is an issue too. I didn't like the Eos R's handling or user interface, it felt too much like a digi cam and I didn't feel like I was fully in control of the camera. I think the EF to EF converter that allows a filter to existing legacy unfilterable wide lenses is a massive benefit. There's the cost too, a pair of R5's are eye wateringly expensive and the R3 is just rich boys play thing. I can't image that it will be popular with the working class pro photographer who has to actually fund their own gear. The RF lenses look amazing, but their pricing is just nuts. The lens portfolio seems swollen with stunt / bragging head line lenses, I'm sure the 28-70mm f2 is an amazing optic, but it's huge, heavy and very expensive. It also doesn't deliver quite enough to fully replace a pair of fast primes.

When I look at the benefits of a pair of 5D mk 4's offer and a bag of excellent lenses...the cost of ownership is a major consideration. Sure it's nice to play with the latest state of the art gear, but to provide a regular photography income in a post covid market...the gear I have is still king.
 

cayenne

EOS R6
CR Pro
Mar 28, 2012
2,626
585
The ironic thing is...I'm finding with mirrorless, I'm actually shooting older fully manual lenses MORE and more.....

I'm spending less on new glass for the most part, and more on adapters and fun vintage lenses.
 
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Ruined

EOS R
Aug 22, 2013
930
59
When I look at the benefits of a pair of 5D mk 4's offer and a bag of excellent lenses...the cost of ownership is a major consideration. Sure it's nice to play with the latest state of the art gear, but to provide a regular photography income in a post covid market...the gear I have is still king.
I still can't believe I just snagged a pair of brand new, fully canon USA warranty-covered 5DsR cameras for $3000. A couple of years ago it would be a clip more than that for one! IMO you can do a lot more with a 5DsR on each hip than a single R5 ;)
 
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chik0240

EOS M50
Dec 31, 2016
48
17
The ironic thing is...I'm finding with mirrorless, I'm actually shooting older fully manual lenses MORE and more.....

I'm spending less on new glass for the most part, and more on adapters and fun vintage lenses.
Can be when you will be able to nail focus with zoomed in EVF, but somehow I still feels odd when using mirrorless, as the colour tonality changed too much from actual scene for once a while when I selected say landscape profile, and up till now with the Sony A9 and R5 I can still basically see a flashing screen with the barely discernable pixels which takes away that mechanical feel
 

Del Paso

M3 Singlestroke
Aug 9, 2018
1,238
1,312
The ironic thing is...I'm finding with mirrorless, I'm actually shooting older fully manual lenses MORE and more.....

I'm spending less on new glass for the most part, and more on adapters and fun vintage lenses.
That's exactly what I bought my EOS R for, being able to consistently focus Leica R lenses, otherwise, I by far prefer using the 5D IV.
What I particularly dislike about the R is the EVF in high contrast situations, like forests in spring. The viewfinder picture you get is totally unnatural, too contrasty, even manual focusing becomes uneasy. I still am hoping for a radical improvement of the EVF, Sony's A1 and Leica SL 2 have become "quite" convincing. Maybe the R3's EVF will be the one?
 

cayenne

EOS R6
CR Pro
Mar 28, 2012
2,626
585
Can be when you will be able to nail focus with zoomed in EVF, but somehow I still feels odd when using mirrorless, as the colour tonality changed too much from actual scene for once a while when I selected say landscape profile, and up till now with the Sony A9 and R5 I can still basically see a flashing screen with the barely discernable pixels which takes away that mechanical feel
Interesting....

I guess I never really look at the colors or tonality, etc in the viewfinder...I look there purely for focus and composition.

I figure if a color is off, etc...I'll tweak that in post, but when looking through the viewfinder is it pretty much purely composition for me.

I've visualized the color (or monochrome) and tonalities before I raise the camera to my eye....

cayenne