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Physioz
30-08-2016, 4:17pm
I sometimes struggle to get manual focus, even with LiveView, on my 70D primarily because of my not-so-good-anymore eyesight. I read an article on macro photography where the author mentioned how useful a focusing screen (FS) was for macro and /or fast lenses. I presume these focusing screens replace the default camera one? Canon makes a FS for the 50D and 60D which apparently is also compatible with the 70D. Does anybody know if these screens impact on autofocus? Also, comments on a FS vs LiveView focusing or related would be greatly appreciated.

raysul
30-08-2016, 5:21pm
Hello Physioz,

Ok I nothing about focusing screens, but of recent have be doing a lot of macro photo's with my 60D, and what has helped me a lot with that is a 3rd party program called Magic Lantern, it has feature's similar to focus peaking which helps a lot. There is a lot of info about it and it's free. Just check it out

Ray

piczzilla
30-08-2016, 5:58pm
During out recent meetup, an APeep (Cage) suggested getting a Focusing Rail. Perhaps it's something you want to consider? i.e. tripod + focusing rail + live view (zoom in/out for precision). I think this will be a lot more helpful than a focusing screen, especially since you mentioned deteriorating eyesight.

On another note, I had Katz Eye split screen installed on my D90. While it didn't impact the AF, I found it almost useless for macro shooting (other users might have different experience)

I hope this helps.

- - - Updated - - -


Hello Physioz,

Ok I nothing about focusing screens, but of recent have be doing a lot of macro photo's with my 60D, and what has helped me a lot with that is a 3rd party program called Magic Lantern, it has feature's similar to focus peaking which helps a lot. There is a lot of info about it and it's free. Just check it out

Ray

Never knew there's such a thing. Looks extremely handy :eek:

raysul
30-08-2016, 6:35pm
Also as an added information, Magic Lantern is only for Canon and Nikon cameras. As my eyesight is failing, one of the features I find very handy is you can set it up for once the subject is in focus the camera will automatically take the picture, and it never misses

 

Ray

piczzilla
30-08-2016, 6:49pm
Also as an added information, Magic Lantern is only for Canon and Nikon cameras. As my eyesight is failing, one of the features I find very handy is you can set it up for once the subject is in focus the camera will automatically take the picture, and it never misses

I've been researching it extensively since I read your comment, I don't think it works for Nikon :(

raysul
30-08-2016, 7:21pm
Your right it's only for canon and it doesn't support all camera's either which is a bummer really, I find it extremely handy.

Ray

Physioz
30-08-2016, 7:48pm
Piczzilla - I don't know much about focusing rails, other than what they are. Typically, do they enable finer movement(s) than that obtained with the focusing ring on a lens. In particular, I rented a Canon EF 100mm 2.8L IS USM (a fantastic lens) but really struggled. Had it on the tripod and live view (10x) but found that getting exact (manual) focus was difficult 'cos even a small shift of the focusing ring made a "big" change to the focal plane i.e. I would invariably overshoot the 'correct focus' then overcorrect ...

Mark L
30-08-2016, 8:45pm
Did you have you reading glasses on and what f/stop are you using?

piczzilla
30-08-2016, 9:32pm
Piczzilla - I don't know much about focusing rails, other than what they are. Typically, do they enable finer movement(s) than that obtained with the focusing ring on a lens. In particular, I rented a Canon EF 100mm 2.8L IS USM (a fantastic lens) but really struggled. Had it on the tripod and live view (10x) but found that getting exact (manual) focus was difficult 'cos even a small shift of the focusing ring made a "big" change to the focal plane i.e. I would invariably overshoot the 'correct focus' then overcorrect ...

I have to admit I never use one myself (I'm a handheld shooter). I have however heard good reports about them - this video should explain better than I do.
https://www.youtube.com/watch?v=tTu0KNxeO38

Some of the best macro shooters I'm following use them too.

Before you resort to that though, I'd say give Raysul's idea a try first. It looks like a very effective solution (simpler & cheaper too) if your camera is compatible with the software that is.

arthurking83
30-08-2016, 11:58pm
Focusing screens are good. But note that they are only good! .. not excellent or fantastic or a must have.
For macro photography, I doubt you'll see any benefit.

ps. my two main cameras(D800E and D300 .. Nikons) both have thirdparty focusing screens.

The maina advantage of alternate focusing screens is for when you use manual focus(only) lenses and if they are fast(aperture) lenses .. ie. f/2 or faster.
At f/2.8 you can generally get just as good focus from the standard focus screen as you can via using a better focusing screen.
The difference at f/2.8 is that you'd consistently get (more)accurate focusing from the better focusing screen, than you would with the standard focusing screen.

But, there's a BUT!.
The better focusing screen comes with a major disadvantage in that with slower lenses you will get darker images(through the viewfinder!)
This vf darkening varies tho and depends on the type of screen you decide to change too.

The two types of screens I have are: one from focusscreensdotcom(D800E) and one from Katzeye(D300).
The Katzeeye is just brilliant(in every aspect).
This is how focus screens should be made, but I suspect that the manufacturer is more concerned about costs than quality!
.. anyhow, enough grumbling .. Katzeye is just brilliant, but(I told you there's always a BUT!!! :D) .. they shut up shop. For all intents and purposes, you can't get them any more.

.. so, focusscreendotcom it is then.
They have many types of screens, and a very popular type is the so called S-type(it's a Canon type screen).
The grain of the screen is structured so it's inherently dark with any lens up to about f/4.
It's great if you use an f/2.8 lens(where it's just a wee bit darker) and better if the lens is f/2 or faster :th3:
You can see the image coming into sharp focus with this S-type screen.
(again another but coming) .. this is only for normal shooting situations.
I assumed that it may help with some manual focusing closer-up shooting too, but it kind'a doesn't.
Actually a more accurate way to describe it is the inherent darkness of the screen type offsets the fine grained accuracy.

The lens you use can effect the (manual) focusing ability too.
I can't think(off the top of my head) of any modern macro lens that doesn't lose aperture as you focus closer.
While the Canon 100 macro lens doesn't indicate this lost aperture value in the vf info, it does happen.
It's called working aperture.
Basically, as you focus closer, the f/2.8 fast-ness of the Canon lens will almost certainly be more like about f/5(even tho you have it set to f/2.8, and it's telling you it's at f/2.8!!) .. f/5 real aperture via a more accurate(and inherently dark) focisng screen is really dark(unless you're using a Katzeye type screen)

The Katzeye only really darkens(perceptibly) at about f/8(ie. with an f/8 lens or a proper manual lens set to f/8).
By comparison, the S-type screen with a lens set to f/4 is about equal brightness to the Katzeye at f/8.
Use a lens at f/8(proper) with the S-Type screen, and it turns day into night! ;)

The above description of the camera taking the exposure when focus is achieved is called focus trap.
(as above) works well for general photography situations, maybe some close up work ... but not so good for macro.
Reason is basic .. focus has two meanings.
1/ focus has only one plane. It's a very thin line and is very hard to get absolutely perfect.
2/ focus zone. There is a zone of acceptably sharp focus. The lens(type) and aperture used as well as shooting distance and viewing size all make a difference to how well this works.

Focus trap replies more on #2, than #1.
Macro .. ie. literally 1:1 macro, not just closeups! .. it's a lot more difficult to get focus spot on using zone focusing.

OH! and if you ever see any inference to focusing aides like split prisms and micro prism collars... again for macro, not quite useful(as you'd hope they'd be).
Again Katzeye did a brilliant job of their focusing aides, but all the others are crap. Crap in that once the aperture is stopped down to about f/5.6ish .. they black out to the point that they are crap! :D
I've had the Katzeye working at about f/11 :th3:

As for if these alternate focus screens impacting AF(or metering, as has been suggested by some folks) .. to be honest I've never seen massive metering issues ... maybe some inconsistent metering .. possibly :confused013 .. but never any AF issues.

I tell folks that should try them(at least). If you can afford the $100-ish odd .. then worth a try. As long as it's an easy to fit solution.
On a Nikon body, it's a 5 min job to install a new screen .. so if you don't like it, it's a simple matter of going back .. or you can swap them out as you see fit for a specific occasion in the middle of nowhere if you have too!

Only because I have one, if you do want an alternate focus screen, I'd recommend the focusscreendotcom types.
Good company to deal with, prompt, prices are OK-ish ..
I remember paying about $90 for the D800E from them, but (due to exchange rates) paid more like $160 for the smaller D300 Katzeye screen .. the Katzeye screen was the better value for money.
Where the D800E screen change made (say) a 10% improvement overall .. the D300 Katzeye screen is more like a 100% improvement overall.

summary:
if you want a better focus screen for macro only .. I'd say you won't really see any significant benefit. (that's just a theory, of course I have no idea on your style, likes/dislikes/etc)
BUT!(see!! again :D) .. if you want it for general photography, and you have fast enough lenses .. for sure.
if you don't have f/2 and faster lenses ... forget it. it'll be a backward step for 'ya.

Physioz
31-08-2016, 11:43am
Focusing screens are good. But note that they are only good! .. not excellent or fantastic or a must have.
For macro photography, I doubt you'll see any benefit.

summary:
if you want a better focus screen for macro only .. I'd say you won't really see any significant benefit. (that's just a theory, of course I have no idea on your style, likes/dislikes/etc)
BUT!(see!! again :D) .. if you want it for general photography, and you have fast enough lenses .. for sure.
if you don't have f/2 and faster lenses ... forget it. it'll be a backward step for 'ya.

Arthurking83, thank you for that detailed reply. This would be for macro only, so based on your comments (and a bit more research which agrees with you), I'll not be looking any further at focusing screens.



However Piczzilla's link to a Youtube video on a focusing rail has got me looking in that direction


I have to admit I never use one myself (I'm a handheld shooter). I have however heard good reports about them - this video should explain better than I do.

https://www.youtube.com/watch?v=tTu0KNxeO38

Some of the best macro shooters I'm following use them too.

Before you resort to that though, I'd say give Raysul's idea a try first. It looks like a very effective solution (simpler & cheaper too) if your camera is compatible with the software that is.

I'm not sure about Magic Lantern (thanks Raysul!).


Mark L
Did you have you reading glasses on and what f/stop are you using?



Yes I did for live view. I tried F2.8 to F22 and back many times ..

arthurking83
01-09-2016, 3:48pm
A point I want to be clear on:
don't be discouraged by my remarks about the limitations of focusing screens.
if you have any interest in manual focusing in any way, eg. you like to have more/better control over your lens .. or that you want to delve in old, unique, lenses for the fun of it.

In that situation, the focusing screen will help!
I just don't think it will for macro work.


....

Yes I did for live view. I tried F2.8 to F22 and back many times ..

Note that some cameras work differently to others when using liveview mode. Check to see how your particular models operates:

1/ some cameras working in Lv mode is that the lens diaphragm operates in real time.
That is, as you set the aperture value, during Lv mode, the aperture may actually be set to that value as you make the change.
2/ some cameras work differently in that they maintain the same method of diaphragm operation as they do in normal vf operation.
The advantage in this is that you get a brighter image. BUT! .. the disadvantage is that you don't see the DOF nor as much contrast as you do in real time aperture operation.

The ideal camera would allow switching between each method of operation.
That is, one mode for wide open Lv mode and auto stopping down when the image is to be exposed, and real time mode so that you can see in real time the DOF, contrast, focal plane .. etc.

Note that it's not uncommon for a lens to have what's known as focus shift.
That is, in normal operation the aperture is held wide open.
When you expose for the image, the aperture is stopped down only for that moment.
Lenses with focus shift result in the problem that at wide open aperture setting, the focus is along one plane, but when stopped down the plane of focus moves(and usually backwards .. that I've ever read of and seen).
The DOF usually masks the issue for normal imagery, but at macro level, it may not mask the issue enough.

I doubt that the Canon 100/2.8 is affected by focus shift, but you may want to do some research on it.

Physioz
10-09-2016, 3:57pm
Solution - remove major technique error(s). Great light (windows), tripod, remote release, immovable object etc BUT even subtle weight shifts on the wooden floor, post-focusing, were causing a small amount of camera movement. It was blinding obvious as soon as I tried outside - the manual focusing in live view was great. Lesson - just because it's on a tripod, doesn't make it stable. Thanks for advice esp arthurking83

arthurking83
14-09-2016, 8:08am
Solution - remove major technique error(s). Great light (windows) .....

Ah! I see you're doing proper macro(not the more usual close focus and crop).

Wooden floors! .. the macro photographers nightmare. BTW! .. don't have you're washing machine going at the same time either! ;)

For 'better light' get yourself a pair of strong LED lights that can be anchored in multiple and various ways.
Check ebay .. I've seen some nice right angled torches on there for decent money.
I just don't have the cranial capacity to remember to get a pair myself .. but this thread just reminded me again .. before I forget again after I get back from work :p

For better critical focusing, it's best to have harsh light, so the main way you'd use those torches is to come in from the side of the subject to create strong shadowing. Strong shadowing from the side will create better contrast.

by definition, contrast is the apparent differences between different tones, and bright tones (ie. white) set against dark tones(black! .. or shadows) is better.
You don't necessarily need to shoot with this light, so it's really only to help in achieving focus .. especially in Lv mode where you can see more detail.

OH! and back on the topic of dodgy wooden floors.
What I do is to set the camera up in my little room where I do this stuff, and use a wireless remote. Camera is set to mirror lockup mode. I walk into the next room and stand in the doorway(strongest part of any wooden floor system).
This is just to eliminate the vibrations that I'm causing in not being able to stand still for 1/30s! :D