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ElectricImages
28-04-2011, 12:58pm
Hiya Ausphotographites,

I'm interested in getting a new focusing screen form my 5DmkII as I've heard that the S-type screen can significantly improve the accuracy of manual focus through the viewfinder, and I prefer to focus using the viewfinder rather than having to use Live View if possible.

Has anyone had any experience with the Super-Precision (S-type) screen? Is it worth the $100 or so to upgrade?

Thanks,
L. :)

andylo
28-04-2011, 2:03pm
On top of that, if anyone has any article about the difference between different focus screens, please let me know. I had done 3 hours worth of google the other day and I couldn't consolidate anything that is useful :(

arthurking83
28-04-2011, 9:40pm
I don't know about any Canon specific focusing screens, but I do have two experiences with thirdparty focusing screens.

First of all the type of screen is important for what purpose you are using it for.

That is, if you want more accurate manual focusing say for macro, then of your camera is live view capable, you won't get a better focusing aide than Lv mode(in usable light tho!!).

If(like me) you want it more for easier and more accurate focusing with manual lenses, or for overriding AF as you please, then a focusing screen will be of help.

Initially I purchased a generic no name focusing screen from Ebay for about $30.
The only focusing aide it had was a split prism, which works great with the majority of decent manual lenses, but once you get a lens down to f/5.6 the blackout was more of an annoyance than anything else. Still helped a little, but mostly annoying.

Note that a 'screen matte' is defined as the opaque screen in it's entirety, and that 'focusing aides'(such as microprisms and split prisms and any others) are referred to separately from the screen matte(or focusing matte).
And also bear in mind again that I have zero experience and knowledge on Canon gear(and in this case focusing screens) there are some things that you should to be aware of.
If this S type screen has a more precise screen matte that allows you to focus more accurately with faster lenses, you may find that even with these faster lenses(f/2.8) the viewfinder may become slightly darker than it used to be.
As you mount lenses with faster max apertures, the difference becomes less significant, but at f/2.8 is where you may notice it(in a side by side comparison).
Once the new screen is fitter, I doubt you will be bothered by the very slight darkening with an f/2.8 lens. BUT if you mount a lens that is any slower(say f/4) then the darkening becomes more apparent.
Fit any f/5.6 max aperture lens and the darkness(of the viewfinder) makes using that lens much less usable(or enjoyable), even in acceptably low light. Where your f/5.6 lens looked quite ok, it will now look more like a f/16 lens with an restrictive hood fitted!

That's simply the way focusing mattes work, and changing it may have an impact on metering.

With my D70s(which desperately needed anything as the viewfinder was woeful!) I fitted this ebay screen. I thought for $30 it can't really hurt, and it was interesting.
Help somewhat with a few manual lenses I had and I could use my 500/8 in some instances, but again the split prism blackout used to be more annoying than helpful.
Screen matte was still an f/5.6 type, and I can't really say I found any significant differences in vf brightness between the two.
(note it is extremely difficult to visualise the difference without a side by side comparison).

I also got myself a KatzEye fpr the D300, which didn't really need a 'better' matte screen, other than for manual focusing fast lenses.
Screen brightness and 'accuracy' of the D300 was rather good(for a DSLR) but not good enough to manually focus an f/1.2- f/2 lens accurately with consistency.
KatzEye's matte screen is definitely more accurate for focusing, and brightness hasn't been affected for lenses up to f/4 or so.
The f/5.6 lens I do have is most certainly darker now with the Katzeye screen even though I went with the brightness enhancement option too(Optibright) which helps to minimise the darkening effect on slower lenses of the higher contrast matte screen.
Problem is that Optibrite adds a considerable amount(50%) to the screen cost, but I reckon one worth taking up.

KatzEye is highly recommended, and even tho it is pricey!... (cost me $200 or so, where I could have got a decent alternative for $70-80) but, after reading a few favourable reports on other sites, I though ... better to get it once and be done with it.

If you want assistance with manually nailing critical focus, then a focusing screen is not the answer.
It'll simply help you get a consistently higher hit ratio, but not 100%. AF is certainly more reliable.
LiveView is dead on perfect, as long as the contrast ratio of the scene doesn't overwhelm the LCD's ability, or there is enough light.

There are a few sites that help to answer SOME questions about the various screen types available, but none of them may actually answer any specific needs that you may want dealt with.

For me it was very simple:

I wanted a (screen matte) that allowed me to manually focus my f/1.2 lens more consistently, but didn't want the associated darkening that this brings for an f/8 lens .. I think the KatzEye works as advertised.
For me the split prism and micro prism collar were more of a bonus. They work well, and the micro prism collar is large enough in the centre of the screen, and around the split prism, to be useful.

joffa
28-04-2011, 11:08pm
I bought the Eg-S for my f/1.2 lenses and it made a BIG difference. It made manual focusing so much easier... It does get a bit darker with a f/4 lens but not so much so that it's un-usable. I haven't tried it at night though, but then again I wouldn't really use an f/4 lens at night unless I was doing a landscape or a cityscape or something, even then I'd just use liveview for that anyway.

Definately worth the money!

ElectricImages
29-04-2011, 7:32am
Thank you arthurking83 and joffa. That's REALLY insightful and helpful. My slowest lens is f/4, my other lenses are f/2.8 or better, so a precision matte screen may well be a workable option without many drawbacks.

If only there was a "most helpful post award" this month, I would nominate you for sure ArthurKing83 - that is an awesomely detailed and informative reply. :)

Thanks again! :)

carrg1954
01-05-2011, 10:36pm
this may be helpful
http://atinyblip.com/articles/photography/eos-focusing-screens/

arthurking83
02-05-2011, 7:36am
In terms of pre visualising what the screen will look like, Focusing Screen.com (http://www.focusingscreen.com/index.php) has the best laid out site.

In the link, look on the left hand bar under Information, and go to the Screen Comparison tab.
In there you will see this chaps comparative images of his screens.

Great way to see what it is you get before you commit to purchase off his site.
His screens look to be very well priced(but as I said.. I went with a KatzEye based on other feedback I enquired about).