Ok, it may not be over yet. I received a quick email reply from Jim at Brightscreen and he's going to work on a solution.
Personally, I think it's the 5D. Canon has done something evil to it. I've had lesser quality screens that screwed up metering in the 20D and the 350D that worked. They were much, much more difficult to install and I never could get them to line up correctly. The Brightscreen lines up perfectly and the larger microprism and split make it a much less cluttered space.
I still have a little bit of hope. I love doing macro and the diagonal split would be...let's say...the cat's meow?
This 5D works perfectly, without a shim. It just may be that the 5D just does not have the Quality Assurance that the 1–Series seems to have, and hence the need for shims in some of them.
I can see how the shim will help a forward-focussing example, but cannot see what can be done with an example that looks in focus in the finder, and produces its actual focus behind that point, as some have shown here. And I still can't see how the standard finder can be MF accurately, and the Brightscreen not.
On another note, I find that the Proscreen (large microprism-only focussing aid) produces more consistent MF results than the diagonal split prism which, now that I have shot almost a thousand images with the prism-only screen. As well, I now find the diagonal prism–micro-prism version clutters the viewfinder. Here is a shot I took this morning, with the new target (thanks Tim!):
cheers, kl
(5D, Apo-90 @ ƒ2, focussed on the bottom edge of the "focus here" bar)
" This 5D works perfectly, without a shim. It just may be that the 5D just does not have the Quality Assurance that the 1–Series seems to have, and hence the need for shims in some of them"
I agree
Now I m thinking about the microprism only screen, did you have to get used to it ? Do you have very good eyes ?
Why would 2 separate Canon brand screens seem to work pefectly while my diagonal split Brightscreen backfocuses? My standard screen and the Ee screen work fine. The Brightscreen seems to seat down all the way and even has a little horizontal play so I don't think one of the edges is keeping it from seating. I installed the shim and it doesn't do anything.
" This 5D works perfectly, without a shim. It just may be that the 5D just does not have the Quality Assurance that the 1–Series seems to have, and hence the need for shims in some of them"
I agree
Now I m thinking about the microprism only screen, did you have to get used to it ? Do you have very good eyes ?
I do have good eyes, and 20+ years using them focus-wise (stills and pro-video). Nonetheless, it took a while to re-learn MF for all work; now I would not use AF, unless I was shooting sports. The microprism-only screen works much better for me.
tfloat/rathman
In the scenario tfloat cites, 100% agreement—what about the others? With the standard Canon screens (referring to the 5D) I will argue here that the user cannot see well enough to be able to say that MF works properly (or does not work properly), to the critical degree some posts here have shown. I have tried both Canon screens personally and feel that the Brightscreen/Proscreen allows closer/more accurate focussing than either of the Canon screens. Point is that AF does not depend on the screen... Of course, that's just one person's experience. Actually, that sounds a bit harsh. I am interested very much in finding out the answer to this conumdrum. It's late; more tomorrow.
I was really interested in one of these when it was first talked about, but I had reservations due to price/shipping to Europe. Having seen what's been happening I am really glad I held off. Seems as tho the canon screens are fine in the 5D, so you would conclude it's a Brightscreen issue.
Hopefully Brightscreen will be able to solve the problems, as there's not much point spending a large amount of dosh for a screen that doesn't perform accurately. Are there any working alternatives to the Brightscreen yet?
Until then, I'll wait to see how things progress before splashing any of my cash.
p.7 #10 · Microprism-only Brightscreen on Canon 5D
Kit,
I agree with you about the human side of this. That is why my Brightscreen p235D is sitting next to my computer still in the box. It has been too many years since I have used manual focus, and my eyes are a lot different now.
My 5D af has been pretty good, until I started using the 85 1.8 at 1.8 under 10 feet, and it is sometimes slightly off, probably in spec but still off a little, enough to bother me.
Gotta get off my rear end and test the screen/Harvey combination.
I have a feeling I will be negotiating a trade with Brightscreen guys for a microprism version only.
In this digital age it almost looks to me like we should invest in an optical test bench to verify camera performance. Think I will go out and take some pictures first.
p.7 #11 · Microprism-only Brightscreen on Canon 5D
MarkSaperstein wrote:
For 5 times the cost of a Canon screen, we shouldn't have to worry about shims and other fixes. Is it really that difficult to make a screen with the same dimensions as the Canon screen?
--Mark
Mark, I was being facecious. I feel that the 5D must have slight quality control issues. I don't believe the Brightscreen is the error...that's all.
p.7 #12 · Microprism-only Brightscreen on Canon 5D
Just FYI:
I received another email from Jim today. It was really nice for him to email me on a Saturday.
They are working on it now and hope to be ready by about mid-week with a fix for me. He states that the majority of customers are not having issues, and they have not found any issues with their own testing. They have tested the screens in several bodies. My problem seems to be random with only some cameras and can be quite complex.
Also, I know I'm getting older, but my vision was fine to MF with the standard screen, so it can't be my vision or lack there of. I am, by the way, 20/20 without glasses for distance. I have a slight error for distance of -.75 Diopters, but that's nothing. I don't need glasses for the computer either, just for fine print. It's called presbyopia and we all get it between 40-45 years old unless your really myopic. Then you just take your glasses off for near.
The lens inside your eye becomes less flexible with age and the muscles that work it are also weaker. This lens is what becomes a cataract, so it also gets clouded. When we try to change focus from far to near, when older, it takes longer and the lens just won't fatten up (more convex) enough to move the focus point close enough.
p.7 #13 · Microprism-only Brightscreen on Canon 5D
Leah,
You wrote: I want the split image for tight macro shots.
I have used both screens, and for macro work (~half my product work) the microprism-only screen is better, IMO. Against dark items (black olives!) you just can't see the edges—so the diagonal is not going to help. I found myself using the surrounding collar for most focussing in these situations, even when there was an edge. The Microprism-only screen is so good, you can seee focus being pulled across something if you are looking along it (I was shooting strawberries FF last week, and as I focussed I could see that zone travel across the surface! And no diagonal is a MUCH cleaner VF.
Actually, I am going to go out on a limb here and say that for me at least, the diagonal is NOT as accurate to focus with, on clear horizontal edges. I can offer a geometrical reason to do with lengths of hypotenuses, if anyone's interested. For horizontal edges, a vertical split is better, and vice versa—which we can't have on the one screen. Enter the diagonal; but this is a compromise, IMHO. Now that I am used to the Microprism-only screen, I am certain that my percentage of pin-sharp images have increased. I can really SEE when something's sharp, now, so no uncertainty. 2¢'s worth, kl
p.7 #14 · Microprism-only Brightscreen on Canon 5D
Leah,
I'm having a similar issue with my Brightscreen #2 for the Canon 5D. Mine is severely back focusing. Tested with and without the shim...no difference. Tested with Canon original screen as well as Ee-S...both were perfect.
My test was conducted using the same focus test chart you have, 45 degree angle, cable release, tripod. The Canon screens were dead-on...the Brightscreen wasn't. While I agree Canon has QC issues evident by some 5D bodies requiring shims and some not the bottom line is this - Canon screens are dead-on. Not so with the Brightscreen. BTW, my body has two Canon installed silver shims. I didn't realize I had them in there until I blew some air in there, one came out and I had to carefully fit it back in. Perhaps many may actually have these in their cameras and not be aware of their existence?
I will add that that while using Canon lenses the Brightscreen still back focused but not as severe as my Contax 28mm. With the Contax it’s just awful and completely unacceptable...but when I switch to the Canon screens problem goes away.
p.7 #15 · Microprism-only Brightscreen on Canon 5D
I did an extensive battery of focus tests over the weekend with my 5D and both the Canon screen and the Brightscreen (13mm microprism only) screen. All shots were of a custom target mounted on a plywood base at 45 degrees, with everything level and square. Tripod mounted, MLU, and timer used for all shots. Each lens was tested with 5 shots and (for the Brightscreen) at all 3 of the focus screen settings available in the custom menu. All images were defocused and refocused between shots. Deviation from the focus point was averaged across all 5 shots. What I can confirm with my gear is:
1) Relative to my Canon screen, my Brightscreen backfocuses
2) The custom menu focus screen setting that brought the Brightscreen results closer to correct focus was setting #1, but the focus error is still not acceptable
One comment I'd like to make is that at the wide open apertures people should be testing focus at it can be very difficult to be sure that out of focus edges are due to a focus error versus softness attributable to the lens working at that aperture. This can be an issue with the D70 focus target some people appear to have been using.
The backfocus issue is a shame of course. I do not have my shims yet - will try them out when they arrive. I suspect given the backfocus tendency they will not fix the problem....
p.7 #16 · Microprism-only Brightscreen on Canon 5D
This is very interesting David. How much of a difference was there between the various custom focus screen settings? I'll try using setting #1 to see if my situation is improved.
Edited by Mike Hatam on Mar 05, 2006 at 01:49 PM GMT
p.7 #17 · Microprism-only Brightscreen on Canon 5D
Mike, the differences were variable with lenses but in my case overall there wasn't as much difference between the default setting of 0 and 1 as with setting number 2 which for almost all my lenses gave the worst result.
I think it's important that I stress there's a good deal of variability I observed in all of this and I suspect there's a factor of people simply not being able to nail focus that accounts for at least some of the results posted here.
If I look critically at my own results I am surprised at how hard it was to have consistent results with the same lens....the truth is I simply couldn't get really consistent focusing with some lenses irrespective of whether I was using the Brightscreen or the Canon focusing screen. Particularly with the wide end (the 17 end of my 17-40, or my 21m Zuiko) I am afraid (ashamed?) to say that over a series of 5 shots I had results showing a fair range - granted they tended to always be either back or front focus but the variation in degree of misfocus was a surprise.
Still - the overall conclusion is one I feel confident in. In my case the Brightscreen is backfocusing.
p.7 #18 · Microprism-only Brightscreen on Canon 5D
ok...I tried the test. 90mm TS f2.8 (tilt set to zero, heh, heh) used this because my other lens is the 24-105, only f4.0. diagonal microprism Brightscreen
found the brightscreen produced an inmage focused 6mm in front.
repeated with the shim, no change!
changed to the S canon screen (actually quite easy to determine focus.) spot on.
