Anyone care to enlighten me on focussing screens?

[vfilby]

I saw one mentioned here ( http://photography-on-the.net/forum/showthread.php?t=49612 ). I think the model was EC-B. Os this anything like the old split prism? Do they put split prisms on cameras anymore? I would really love a manual focussing aid.

My apologies if this should be obvious, my google search turned up only offers to sell.

[vfilby]

Also, I did notice that these gadgets seem to be for EOS 1 series cameras. For the time being I only have a rebel (which suits my needs really), Do they make any of these gadgets for the rebel?

Cheers,

[Scottes]

Sorry, not for the Rebel, 10D, or 20D even. :cry:

[vfilby]

Bah!

Can't we trim the edges to make it fit on the rebel? ;-)

[IanD]

Bah!

Can't we trim the edges to make it fit on the rebel? ;-)
Vince,
If you take a real sharp pointy object, say something along the lines of a scrawl (www.leevalley/markingtools.com) you can make your own custom screen! Just remember to use a rocket blower to get rid of the plastic you will remove.
:lol: :lol: :lol: :lol: :lol: :lol: :lol: :lol: :lol: :lol: :lol: :lol:

[vfilby]

Now these focussing screens are basically just square pieces or plastic or glass right? How do you put them into the 1 series cameras.

My understanding is that they sit on the upper part of the CMS chamber, right about the primary mirror? Is this correct?

Maybe I'll have a DIY project soon! ;-)

[PacAce]

Just realize that the micro-prism viewfinder, if that's what you're going to DIY into the DRebel, will mess up your exposure meter readings in evaluative mode and to a lesser degree in center-weighted average mode.

[vfilby]

Just realize that the micro-prism viewfinder, if that's what you're going to DIY into the DRebel, will mess up your exposure meter readings in evaluative mode and to a lesser degree in center-weighted average mode.

Can you be more specific or provide a source for details?

Thanks,

[steven]

For a 1Ds there is a catch above the mirror that you press. Then a tray like aperatus comes down and the focus screen is there. There is a little tab that you use a special tool (comes with the replacment screen) to grab the tab and lift it out. Then just place the new one and push the tray back in place.

As to messing up your metering.
I thought that the sensors were located behind the mirror and the mirror was a partial mirror letting some light through for the meter.
Guess I have that wrong :?: :?

[Ogrt48]

Actually I think it's this Yahoo group but theres a group of people making custom focusing screens for the Rebel on their own.

http://groups.msn.com/TheCanonDigitalRebelPartisansGroup/general.msnw

[PacAce]

Just realize that the micro-prism viewfinder, if that's what you're going to DIY into the DRebel, will mess up your exposure meter readings in evaluative mode and to a lesser degree in center-weighted average mode.

Can you be more specific or provide a source for details?

Thanks,

The following is a quote from the 1DmarkII user's manual:


The Ec-A, Ec-B, Ec-I and Ec-L focusing screens have prism at the center. A correct exposure reading cannot be obtained with evaluative metering or spot metering based on the center area where there is a prism. Use centerweighted averaged metering or off-center spot metering with such focusing screens.

[vfilby]

Thanks Pac, I'll have to think more about this.

Cheers,