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Guest

Hi All,



There was a mini trade show in shop in Berlin yesterday, and one of the representatives there was from Zeiss. We got talking about focus screens for DSLRs and he then let me try out a Canon 5D (with Zeiss 100/2 mounted) fitted with a Brightscreen split prism screen.

Here's a rundown of my experiences with focus screens so far:



BRIGHTSCREEN

Features a split prism in the centre, surrounded by a microprism collar.

I found the Brightscreen view rather 'busy' compared to regular screens, so it does distract from the image somewhat. The image is also a bit darker than regular (Canon) focus screens.

If you're used to plain focus screen you'll need time to get used to the Brightscreen. In terms of focussing, it does a very good job and makes manual focussing much easier and quicker - except in very critical situations it would probably be unnecessary to switch to live view for checking the focus.

On the downside, these little bits of plastic cost around 180 euros (in Germany), so you'll need to be a dedicated manual user to splash out so much money.



CANON STANDARD SCREEN

Nice and bright, but you need eagle eyes to focus at wide apertures with this unit. With wide-angles lenses it's certainly useable, but once you start using 85mm or 100mm lenses at f2, you're probably going to get sharp ears and blurred eyes.



CANON GRID SCREEN

In terms of manual focussing, this is basically the same as the standard screen except that it features guide lines in the view. It's quite useful for very precise work (such as architecture), but Canon rather stupidly put the guide lines in quarters, rather than thirds.



CANON EG-S ('manual' focus screen)

This is Canon's best offer at a manual focus screen, and it's quite pitiful compared to dedicated screens sold by Katz Eye, Haoda or Brightview. On the other hand, it's much cheaper, at around 40 euros.

This screen is slightly darker than the standard screen, though not much, and it certainly is an improvement in terms of manual focussing. However, with long telephoto lenses I would think most people will be struggling to focus accurately.



Having used this screen for some time now, I'd say it's a fairly good compromise in terms of price and function, and it works a treat with lenses up to 50mm. However, for longer lenses and very distant subjects (especially at wide apertures), it doesn't

give the sureness one would like, so it's often necessary to switch to live view to confirm the focus.





Does onyone have any other experiences with focus screens - including Nikon, Pentax etc.?

genotypewriter

[quote name='Pinhole' date='19 June 2010 - 09:46 PM' timestamp='1276947981' post='607']

BRIGHTSCREEN

Features a split prism in the centre, surrounded by a microprism collar.

I found the Brightscreen view rather 'busy' compared to regular screens, so it does distract from the image somewhat. The image is also a bit darker than regular (Canon) focus screens.

If you're used to plain focus screen you'll need time to get used to the Brightscreen. In terms of focussing, it does a very good job and makes manual focussing much easier and quicker - except in very critical situations it would probably be unnecessary to switch to live view for checking the focus.

On the downside, these little bits of plastic cost around 180 euros (in Germany), so you'll need to be a dedicated manual user to splash out so much money.

[/quote]



Interesting... how does this compare to the EG-S for off-center focusing?
My experience with non-Canon focusing screens is that although they are a good investment for APS-C bodies, they are much less so for FF. The EE-S for 5D and Eg-S for 5D II are more than adequate for MF, and they do not disturb the AF points either. Furthermore, no adjustments for metering are required either other than selecting the correct focusing screen in the Custom Functions menu. Also, all metering modes work correctly, unlike with any of the add-on screens with micro-prism collar and/or split prism(s).



An added advantage of the -S screens is that they allow one to see DoF more or less as it is, unlike any of the other screens. They also work well with lenses with slower apertures than F/2.8, even though they are specifically made for lenses with an F/2.8 or wider aperture. Another advantage is that these screens are clutter free, and that helps tremendously, IMO, for composition and framing.



Since it is easy to focus manually with these screens, I reckon they are the best investment you can do, focusing screen wise, on a FF Canon body.



I found that with the 5D before, and the 5D II now, I never even need to exchange the focusing screen. The -S type stays put, even with the 100-400L. With the 40D I did change occasionally between Ef-S and Katz-Eye split prism with OptiBright coating.



Are these split prism screens better than the Canon -S screens for MF? IMO, no. You still have the problem with center focus, like we had in the old days. The advantage of the -S type screen is sthat you can actually use it fo rfocusing anywhere within the view the VF gives you.



Regarding sureness for MF with difficult subjects: we have LiveView now, and in the past we used Angle Finders which allowed magnification of the image. I still use my Angle Finder for critical focus and macro work. No focusing screen I know actually allows for perfect focus of difficult subjects anyway, although Eg-S on a 5D II does come close - from my experience, this combo works even better than the 5D Classic with EE-S.



Kind regards, Wim
I only tried the S types screens on 50D and 5D (mk1). With the 50D, it was a "wow" moment when I stuck on the 50mm f/1.8 and could see the region of focus much more easily than with the standard screen. I didn't use it much though, as at the time I didn't have much by way of fast lenses to use it with.



When I picked up a used 5D, I also got the S screen for it. Unfortunately this was more of a disappointment. The difference over the standard screen didn't seem so noticeable. I'm guessing because the view was bigger, even the regular screen was "improved" over the 50D.



In both cases, I didn't like leaving the S type screen in. I found regular zooms (to f/5.6) to be rather dim even in direct sunlight, forget it in darker areas. As I use zooms most of the time (100-400L over 50% of the time), I left the standard screen in. I'd just rather switch to live view if I need to get critical MF accuracy.

PuxaVida

I find MF really enjoying in some cases (macro & still life shots). Therefore I bought Zeiss Planar 50mm 1.4* to use with my D90. The very bright focus screen of D90 makes it very hard and tricky to focus. I thought to order one of those KatzEye but then realized that D3 and D700, (the latter I'm planning to buy in near future) have BrightView Matte focus screens. Can anyone make a comparison between the standart focus screen of FX bodies with the KatzEye products?



Regards,



Serkan

Guest

[quote name='genotypewriter' date='19 June 2010 - 01:34 PM' timestamp='1276950870' post='609']

Interesting... how does this compare to the EG-S for off-center focusing?

[/quote]





Hmm ... the Brightview I tested wasn't that great, but I admit I was mainly testing for the centre focus, which I found very good indeed (better than the Canon by far). I've been using rangefinders for years, so I can live with that limitation - but yes, the Canon S is better for across-the-frame focussing. That said, I still have problems in the far corners with a Canon S, but I don't know if this is a general problem with focus screens.



I believe there are thrid-party high scatter screens like the Canon S, but the Brightscreen I tested was not one of them.

Guest

[quote name='PuxaVida' date='19 June 2010 - 06:20 PM' timestamp='1276968037' post='615']

I find MF really enjoying in some cases (macro & still life shots). Therefore I bought Zeiss Planar 50mm 1.4* to use with my D90. The very bright focus screen of D90 makes it very hard and tricky to focus. I thought to order one of those KatzEye but then realized that D3 and D700, (the latter I'm planning to buy in near future) have BrightView Matte focus screens. Can anyone make a comparison between the standart focus screen of FX bodies with the KatzEye products?



Regards,



Serkan

[/quote]



Hi Serkan, I'm using the 85/1.4 and in most cases the focus is pretty accurate with subjects within a few metres, even at 1.4. It gets trickier in low light situations and when the subject is far away, in my opinion. A matte focus screen should certainly help you to get much more accurate focus, but I don't have much knowledge about the new Nikon equipment I'm afraid.

Comte

When I bought the Zeiss 2/35 for my Pentax K10D, I decided to get a new focusing screen. Because of the totally overpriced Katzeye screens, I finally bought a focusing screen on ebay for 20 Euro, directly from China. It features a micro-prism ring and a split-image. I can hardly see a difference in brightness between the Chinese focusing screen and the genuine one.

It's grain is fine enough to see all details, by far better than the focusing screen on my old Pentax K2.

Focusing is still accurate.

I definitely recommend you to try it out. If you're not satisfied, you won't loose a lot of money anyway.

Btw. I have remarked that the Pentax K10D has no possibility to adjust the focus on the focusing screen. In former times, especially on medium format cameras, it was a tricky thing and you could not exchange the focusing just like that.

PuxaVida

What brand was the one from China?

genotypewriter

[quote name='Pinhole' date='20 June 2010 - 05:15 AM' timestamp='1276974934' post='616']

That said, I still have problems in the far corners with a Canon S, but I don't know if this is a general problem with focus screens.

[/quote]



There are rare times when either the sensor or the focusing screen is not shimmed equally/correctly. These will cause differences in focus between the captured image (sensor) and what's on the VF. And I've heard that misalignment (i.e. focus on one side, etc.) can also be caused by incorrect shimming. I don't think there are multiple shims for the focusing screen, so it has to be your sensor mount then (if there is such a problem at all). Just thinking out loud...



GTW
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