hansovich wrote:
If all Canon screens don't require shims, then the Brighthand shouldn't either if it is compatible.
At least I hope everything will be solved because IF viewing in focus corresponds with being in focus, then the BS would be a nice solution.
Cheers,
Hans
I agree here - if Canon's screen doesn't require shims, why does the Brightscreen?
I'm holding off on buying one until this issue is resolved, and I'm not inclined to want to use shims. I want to be able to easily swap my screens as I did with the 1D II.
Hans—are your Canon-screen images in focus via MF, or AF? That was really what I was getting at. If focus was achieved via AF and Canon screen, there still could be a focussing error whan using the Canon screen and MF, and you cannot see that finder image as well with the Canon screen in my experience.
I agree that asking the question "if a Canon screen does not require a shim in any position, why should a Brightscreen?" is perfectly reasonable—I was trying to eliminate variables.
I don't have the answers; I was asking the questions that might provide these. When I used the 20D, I honestly could not focus Canon lenses manually, accurately and repeatedly, using that finder. The 5D has a much bigger finder image, which is more accurate in this respect. The 20D finds focus with AF lenses perfectly well, but IMO finding that same pin-focus with the Canon screens manually is significantly harder, and harder to get the same results consistently—20D or 5D. That's what I was getting at. kl
No; I was comparing of course MF using both screens. AF already works very nice.
I also had a 20D before and was very happy when the 5D came out in order to be able to focus manually.
Using the canon screen I still have more keepers using AF then MF, but MF mainly is to be used in special situations or using MF Zeiss lenses. To avoid mistakes I did all tests with Canon lenses only.
Bye
Hans
I had convinced myself that my 5D was focusing correctly with the standard screen but back focusing with the Brightscreen split image/micro prism screen. I recently received the Canon Ee-S screen and found that my camera back focuses with that screen also. I haven't gone back to check the standard screen but I suspect that, with the inaccuracies inherent with that screen, during my original testing I was getting some hits and some misses and subconsciously elected to disregard the misses. Anyway, in my case I've come to believe that there's nothing wrong with the Brightscreen and that I need to send my 5D body back to Canon for adjustment.
Johnny; you are not the only one with that dilemma, it seems other people experience the same. The thing is most people actually do get MF right with the original screen, I am one of them. Never a problem. But people have had issues with both the Brightscreen as well as the Canon Ee-S screen. One theory/explanation I have heard is that the original screen is plucked to fit the camera from four different color coded (at the factory) ones because the carrier/tray don't hold specs to enable just one screen to fit all perfectly. This theory could hold water as it would explain why the original screen is spot on whereas other screens are not. I have heard of very few who have had issues with the original screen. My screen actually was a little bit different from the Brightscreen I had, if ever so slightly.
The thing that puzzles me is that if that is true, how can Canon ship out Ee-S screens to customers without knowing what screen has been fitted in the first place? Or has it just been overlooked or are they hoping for just a few returns on the ones they send out?
One theory/explanation I have heard is that the original screen is plucked to fit the camera from four different color coded (at the factory) ones because the carrier/tray don't hold specs to enable just one screen to fit all perfectly. This theory could hold water as it would explain why the original screen is spot on whereas other screens are not. I have heard of very few who have had issues with the original screen.
Henrik: that is an extremely interesting piece of information. Another: my second Canon screen (Ee-S) also worked perfectly—as you'd expect under that scenario when a Brightscreen also works perfectly, Basically, the carrier on my 5D is aligned and located properly, so any properly made screen will work as expected. There were no Canon shims in mine.
I re-read the entire thread just now. As a piece of confirming info, deshojo had the same focussing problems with the Ee-S screen—but not the original one.
Henrik, if what you have said is true, that could be the whole problem right there. And what Johnny wrote above is what I was hinting at to Hans—that there might have been focussing problems but that one might tend to ignore them to some extent. Readers might recall that I had real focussing problems with the original Brightscreen until I adjusted the diopter while really looking at the new finder image. So, what I am suggesting is that the problems ervery one has had fall into one (or more) of three categories:
1. insufficient pressure on screen (so, need shim between screen and carrier)
2. focussing inaccuracies and the tendency to write off poor images
3. Canon manufacturing inaccuracies that require shims above any non-standard screen, and that these are taken care of by the different screens installed in the factory, as Henrik suggested. This would explain those cases where the Ee-S screen does not focus properly.
The final point is that, IMHO, Canon will just deal with the Ee-S returns. This is disappointing.
I am going to write Jim Lakey now about this and see if we can get a confirmation. cheers to all on a great thread. Kit
Gets interesting here. I just don't need another issue on my camera, but if you come down to a ready made solution for an alternative screen I jump on the train. Thanks for going ahead.
kosmoskatten wrote:
One theory/explanation I have heard is that the original screen is plucked to fit the camera from four different color coded (at the factory) ones because the carrier/tray don't hold specs to enable just one screen to fit all perfectly.
I wonder if there are any markings on the original screens that would indicate a certain "fit". That is, I wonder if the people that are having trouble with other screens but not the original have some kind of identifier on the original screen that would differentiate itself from screens used in cameras that don't.
It might be an idea to look carefully for a mark, tab alignment, or other feature as a clue that different screens were used at the factory.
i did some more tests:
previously, i found the split/diagonal brightscreen to focus 6mm in front, with or without the shim. sent it back and am awaiting the microprism only version a la Kit.
in the meantime, more carefully (tripod, cable release, mirror lock-up, canon 2x angle magnifier, diopter checked, shot at f2.8 using canon 24mmTS, and 5D, nikon focus chart, looking down at 45 degrees, about 20" from lens, centered on using the " marks near the 5/64" above and below the word "focus" at the left)
canon stock screen: focussed 1-2mm in front;
canon S screen: focussed 3-4mm in front;
canon grid screen: 2-3mm in front.
brightscreen is in transit to mfg, so no re-test here.
now 1-2mm is not much, in fact the chart starts to be the limiting factor. i would check focus by bringing the upper " into as shartp as possible, then the lower ", then go halfway back to make sure the word focus was ..focussed.
p.9 #10 · Microprism-only Brightscreen on Canon 5D
**Update**
I received the new shim from Brightscreen. It's a lot nicer. It's made of stainless steel, stiffer and a bit larger I think. The plastic shim seemed to fit inside the dimensions of the screen and this one fits at the edge and just overlaps the screen edge.
I put the shim on top of the screen as was instructed and lined the screen and the shim up and then lined both of them up side to side centered in the tray. Pushed the tray up and my screen was perfectly centered. I think the shim being a little larger helps center everything too. (Word of warning, when I had the screen out held by the tweezers blowing it off with canned air, it blew the screen out of the tweezers onto my hairy carpet..now I really have to do a major cleaning of it.) I did notice that my 5D already has two shims mounted above the screen tray. A silver one and a gold one.
Here are some average results with the new shim and my 100 Macro. It does vary as any manual focus would but I think the new shim has fixed the problem. I also have found it works best if I turn my lens counter clockwise first, and then clockwise until I first see the split line up. Now if you had backfocus, you may want to do the opposite.
If there is a void somewhere that makes even the Ee-S screen have errors, the new shim must be stiff enough or wide enough to negate it.
If you want to make sure you get the new shim I'd suggest sending your name and address again to [email protected]. Then they'll know exactly who is having errors and needs the shim. If you're having errors with the Canon Ee-S screen or the Canon grid screen, I'd see if you can get a shim from Brightscreen too. I bet it will work with them also.
I'm sure all new orders will come with the new shim and instructions now that they've got it figured out. I think Jim said they were going to ship the shims by USPS Priority or Global Priority. Now, to see if I can get all the hair and particles off my screen!!!
Edited by Leah Hallett on Feb 11, 2006 at 02:49 PM GMT
p.9 #11 · Microprism-only Brightscreen on Canon 5D
Oh, I had emailed Jim about how to clean my screen since I blew it onto the floor. He just emailed me back and I guess canned air is a no-no. Here's how he said to clean it:
"We never recommend the canned air. Regular bulb type blowers are fine in conjunction with plain 100% cotton balls in a circular motion."
Note to self can the canned air...gotta get a bulb blower.
p.9 #12 · Microprism-only Brightscreen on Canon 5D
Leah,
Great news. And I cannot but agree re. canned air—apart from it just being too strong sometimes, you can shoot propellant onto the screen or, worse, the sensor (if using canned air to clean).
There certainly seems to be much more variation in the 5D's carrier/prism/lens flange measurements that the 1D series folk seem to get. AFAIK, there are no shims in the 1D series—someone may correct me here. Certainly mine didn't have any. Cheers, Kit
p.9 #13 · Microprism-only Brightscreen on Canon 5D
My 1D screen came with a shim - although I didn't have to use it. It works fine without. Also that shim is so thin, if I needed to I would have a hard time installing it.
p.9 #14 · Microprism-only Brightscreen on Canon 5D
Jameel,
That shim is to force the Brightscreen a little more tightly in position. I meant that the 1Ds does not come with a shim from the factory, AFAIK. Cheers, kl
p.9 #15 · Microprism-only Brightscreen on Canon 5D
Can someone point me out to a good ruler for MF tests with the brightscreen. My homebrew ruler is not that good, and before taking conclusions I want to be sure...
Flappie
Feb 13, 2006 at 01:13 AM
jjlphoto Offline • • • • • [X]
p.9 #16 · Microprism-only Brightscreen on Canon 5D
Doesn't really matter if your ruler is accurate or not, all that matters is that what you focus on needs to be exactly what your file shows you when you open it up. All that is really necessary are a series of closely packed together numbers or letters so you can see if the focus on your file has drifted front or rear.
p.9 #17 · Microprism-only Brightscreen on Canon 5D
Flappie, I agree with John Luke there is nothing too special about a focus target. That said, I posted on this thread a while ago that I had developed one that I find useful. No problem to email it to people but I need an email address as the PM system here doesn't allow sending attachments.
On another note I received an email from Brightscreen indicating that I would receive the new shim. Hope to have as good a result as Leah. While the error has been frustrating I think Brightscreen's communication with customers has been responsive and correct.
p.9 #18 · Microprism-only Brightscreen on Canon 5D
I received my new shim today in a nice little zippered case that would hold several screens, shims, chewing gum, etc. they also indicated my replacement screen, no split, would arrive tomorrow.
