[ducdao]

On my K5 I did it with my finger nail. It's easy. Not tools are really needed. Just be careful and don't touch the screen or the mirror.

using the tip of a tweezer would have been easier no?

[DogLover]

using the tip of a tweezer would have been easier no?

Definitely. You must have tiny fingers to be able to get your fingernail in such a tight space. If you don't have metal tweezers (and some plastic, specially-made ones for screens come with every screen), then a tiny eyeglass screwdriver would also work. Just be careful that you don't slip off and hit the screen.

[lammie200]

Does anyone have any good ideas about something common to use to protect the mirror while making screen changes. I am thinking about cutting up a dust mask.

[EVO]

Well I've read through this whole thread and what I'm wondering is whether the ee-s changes the visual characteristics of the viewfinder or merely the brightness and DOF resolution?

I come from a Canon 5D, which has a fsr better vf than the K-5: brighter, less contrast, bigger, clearer etc. The K-5, while being an actual prism instead of mirror, still suffers from the same kinds of strange distortions and blurry edges as you move your eyes around the vf. Does the Canon screen mitigate this behaviour, or is it inherent in the prism?

[DogLover]

Does anyone have any good ideas about something common to use to protect the mirror while making screen changes. I am thinking about cutting up a dust mask.

The only thing I know of that's for-sure safe is a pec-pad. I've never used anything. As long as you're using tweezers or the actual screen-handling tool, you're not likely to drop anything.

[ducdao]

I have a pretty beat up Canon AT-1 laying around and I like the focusing screen a lot. It has the split prism. Does any know which focusing screen (model number) is it and would I be able fit in in my K20D? I guess I would have to cut it though.

[DogLover]

Well I've read through this whole thread and what I'm wondering is whether the ee-s changes the visual characteristics of the viewfinder or merely the brightness and DOF resolution?

I come from a Canon 5D, which has a fsr better vf than the K-5: brighter, less contrast, bigger, clearer etc. The K-5, while being an actual prism instead of mirror, still suffers from the same kinds of strange distortions and blurry edges as you move your eyes around the vf. Does the Canon screen mitigate this behaviour, or is it inherent in the prism?

Never used a 5D but I accept that the VF is considerably better than the K5. I wouldn't think the screen would make that big of a difference, though. I just don't think it could overcome the kinds of things that you are talking about. It is just a screen, after all, not a whole new VF. Those of us that have tried the EE-S are pretty delighted with what it does do, but it ain't a miracle.

[Turtle]

I've read the suggestions for how to cut the screen and don't think this will be an issue, but was wondering if the ee-S screen has a designated center area that is different than the rest of the screen. If so, I understand that when using the original screen as a template it would need to be centered. But if the Canon screen has no real center (like those screens that have crop marks, split prism, etc.), it seems as though the the original K20D screen can be aligned with the lower corner of the Canon screen so that only 2 sides need to be cut. Any thoughts?

Also wondering what can be used to unclip the original screen. I see on the focusingscreens website they include a couple of plastic tools with a little hook. I'm sure I can fins something, but if someone has a suggestion I'd appreciate it!

Thanks to everyone who contributed to this thread, I really learned alot!

See post number 43 and esp. the diagonal lines (used to find dead centre). The screen has a parabolic profile so yes, it is important to keep centres aligned.

T

[sakle2k]

See post number 43 and esp. the diagonal lines (used to find dead centre). The screen has a parabolic profile so yes, it is important to keep centres aligned.

T

Thanks Turtle, I had read that. I asked though because of something dlacouture said in post number 47 which made me think it could be done:

"BTW, I almost cut it "sideways" into the EE-S so as to only cut two stripes instead of four, but the K5's screen width is slightly bigger than the EE-S height... But maybe it could work? Especially for smaller screens such as for the K10/20..."

I guess it will be easier to see once it arrives here today.

My only other concern regards shimming. I see dlacouture described making shims from scotch tape in post #104.

In the end, I used thin stripes of scotch tape... You need 0.15mm less than what your stock screen uses, so if your stock screen was properly adjusted with a 0.40mm shim, then you need a 0.25mm shim for the EE-S...

Superpose several layers of Scotch tape until you reach the needed thickness (I needed 5 layers to reach 0.25mm, so that's 0.05mm by layer), then cut two thin stripes (say, 20mm x 1mm) and position them on the screen's ground side, right against the edge.

If I understand correctly, the tape was layered on 2 parallel edges on the ground side, cut to fit, as opposed to all 4 sides like the factory shim. My guess is to use the factory shim as a guide to how wide the shims can be so as not to obstruct the view. Does this sound right?

Thanks again for your insight.


++++++++++++++++++++++++++
++++++++ UPDATE +++++++++++

I received the screen today and covered both the original and the new ee-s screen with scotch tape, marking an "X" on each with fine point Sharpie.
Using the x's, I centered the original screen on the new one and traced the original.

I then followed what drougge described (post #72) by taping the screen to a piece of wood and carefully cutting the trace lines with a Dremel fit with a cut-off disk at a pretty low RPM. It cut fine with no real melting...any "debris" left could easily be rubbed off with my finger. I found that it was tricky getting the tape off. I used the corner of a razor blade (very carefully) to lift up a corner of the tape which I could then pull back with tweezers.

Since I intentionally cut on the outside of the lines, the tedious part was using sandpaper to "creep up" on the line after removing the tape and carefully holding the screen by the edges. This was a gradual process so as not to sand too deep. I'd sand a little and then tcheck to see if it would fit in the camera. If not, remove it and repeat. Once the new screen finally fit, I removed the Pentax shim from the camera and made shims out of scotch tape. After doing that the focus & DOF preview seems to be spot on.

This whole thing took me about 4 1/2 hours which I didn't expect and why I'm writing this. And in the process I managed to get what looks like a dull spot or smudge on a very small portion of the screen, despite being protected by tape for most of the time, wearing latex gloves and cleaning the screen with Ivory soap and water, then CFC spray and finally wiping with a microfiber cloth. The spot has no effect on performance.

The new screen has given me a new camera. I really can't believe how easy it is to focus at f1.4. I'll play around some more tomorrow, but I'm sold on this. As someone previously said, had I known it would be this involved, I probably would have bought it from focusingscreens rather than doing it myself, but in the end this cost me less than half of what they charge. I guess you have to weigh the options and decide for yourself. I took some pics of the process with my cell phone which I'll try to post tomorrow, maybe they'll help someone else.

[sakle2k]

Here's a few photos I took while cutting a Canon Ee-s focusing screen to fit a K20D. I realize this is the K-5 forum, but it's still relevant. See my previous post for additional info.


Canon Ee-s focusing screen


Alignment Marks - Both the Canon (left) and the original Pentax screens have been covered with Scotch tape and diagonal lines drawn from corner to corner.



Centering the Screens - The lines are aligned.



Template Traced - The outline of the original screen is traced onto the new Ee-s screen.


Cutting with a Dremel Cut-off Disk - I clamped a board to my workbench and used clear packing tape to hold the screen in place. In this picture, the right side has already been cut.



Rough Cut - I intentionally tried to cut outside the lines so that I wouldn't over-cut the screen. The rest has to be sanded by hand using 120 grit sandpaper which took quite a while, but ensured I wouldn't cut the screen too small.



Finished Screen - Once the screen would fit properly in the camera, I removed the factory shim which would be too thick, as the Canon screen is thicker than the Pentax screen. 5 strips of Scotch tape were layered and cut to fit on the left and right sides of the "dull" side of the screen.



Installing the New Screen - Here's the new screen positioned in the mounting bracket in the camera. Notice the scotch tape shims are facing up (away from the mirror).

[vanyagor]

sakle2k, I can not see the pictures. "Content Protected by Owner" is being displayed instead of the image. Is it just me or everyone else has this problem too?

Thanks for the write up.

[excanonfd]

Does anyone have any good ideas about something common to use to protect the mirror while making screen changes. I am thinking about cutting up a dust mask.

I fold a couple of sheets of lens tissue to cover the mirror before dropping the focus screen retainer down to change the screens. If you are careful you probably don't need to do this but better safe than sorry.

[sakle2k]

sakle2k, I can not see the pictures. "Content Protected by Owner" is being displayed instead of the image. Is it just me or everyone else has this problem too?

Thanks for the write up.

Sorry about that vanyagor, should be good to go now.

[lammie200]

I fold a couple of sheets of lens tissue to cover the mirror before dropping the focus screen retainer down to change the screens. If you are careful you probably don't need to do this but better safe than sorry.

...I got some lens tissue yesterday - the supply shop didn't have any pec pads. I hope to try the installation sometime today.

[vonBaloney]

sakle2k -- how's that dremel work for cutting? Did it create heat and melt it a bit or it was a clean cut? (i.e. how close to the actual line can you get safely?)