No sooner did I comment on this on another thread here than I discover a new post on DPR from someone claiming to have developed a combo Micro and Split Prism screen for the 20D. Anyone care to take the risk of ordering one and reporting back?
You can trust Rachael, I bought a micro prism focussing screen from her for my 300D and it works a treat. Plus, she really does do her best to make sure you're happy with her product.
Hey kye78, does the AF continue to work with the split circle screen installed? Does it interfere with the center AF point? What's the installation process?
On the 300D, the screen was really easy to install. All you need is a pair of pointy tweezers (to remove a metal clip that holds the screen in place) and fairly steady hands, i.e. not prone to unpredictable spasms, heh. Just take a little care not to scratch the mirror which is kinda close by. There's a file on the canondigicamhacking forum (Yahoo) that you can download which details the process with some illustrations.
No I didn't get the hi-lux coating, but I might this time round since I tend to shoot indoors.
AF continues to work as normal I believe but since my experience is with the "Micro prism" screen you should email Rachael about the "Split prism" to double check. There's actually three different screens available. "Split circle", "Micro prism" and a hybrid of the two. On the 300D, the "Split circle" screen threw the metering off by 2 stops which is why I got the "Micro prism" instead. The "Micro prism" does not affect metering at all. From what I gather from Rachael's post in DPR, the metering on the 20D doesn't seem to be as affected by "Split circle" screens.
Correct me if I'm wrong - but what is all these hype with all these focus screens with split/micro-prisms?
1) If you're using MF, then you're defeating the purpose of using an AF-camera, and all the associated AF-goodies that came along with it.
2) The prism is only available in the center - are you going to resort to using the Focus+Lock+Recompose method for focussing on off-center subjects again? What are your 3, 7, 9 or 45 point AF points used for then?
3) If you're going to use your side AF points anyway, then what's the purpose of having a micro/split prism at the center?
Most MF cameras have split/micro prism screens simply because multiple-point AF wasn't around in those days. Also most people did not print big, or view 100% like we do in digital nowadays, so the margin for error in focussing was considerably larger, and could cover the focussing 'error' due to the FLR (focus-lock-recompose) dance.
Ask yourself: am I going to shoot dead-center subjects all the time? Why do I need this micro/split prism screen on your AF camera? What kinds of subjects am I shooting that I require a micro/split-prism focussing screen? If you can verbalize out loud with a good reason why you need a micro/split prism, go ahead and buy and install one. Otherwise, I would suggest learning how to use your AF properly - focussing technology is much better than our eyes nowadays.
nutek wrote:
1) If you're using MF, then you're defeating the purpose of using an AF-camera, and all the associated AF-goodies that came along with it.
I find myself using manual focus more and more especially with subjects that are not in motion - or for those shots where I want to take the extra time to do the proper composition.
2) The prism is only available in the center - are you going to resort to using the Focus+Lock+Recompose method for focussing on off-center subjects again? What are your 3, 7, 9 or 45 point AF points used for then?
Well yes - if it's off-centered, then I'll focus with the subject off-centred. I will not focus and then recompose as if the DOF is very shallow you will end up with the subject slightly out of focus as the distance from the camera to the subject at the time you focus will be different after you recompose.
3) If you're going to use your side AF points anyway, then what's the purpose of having a micro/split prism at the center?
Personally never use anything but the centre point. If I shoot something that is off-centered, I use manual focus.
AF works great for me for one style of shooting; moving quickly and grabbing shots I see happening arround me, action, street photography. But I do a lot of tripod work where I'll spend 2, 3, 4 hours setting up a shot. It's very possible there is nothing with contrast in the shot on a focus point, or the light level can sometimes be quite low until my strobes fire (location shooting of architectural interiors). I hate not being able to be SURE that the focus is sharp, befor I break down the set up and leave. To verbalize why I want one, and why I have said so many times since I got may camera about 5 months ago, it's for peace of mind. There have been several occasions when I got home to my PC after even looser out door shooting and reviewed images and found a shot that would be perfect if it were only sharp. Somed days, i don't want a few "keepers" out of hundreds. I MUST have all 3 shots taken in 9 hours to be perfect. So, I would love to have a way to confirm focus visually in the lens. Even with my faster paced shooting, I still want to see for myself, sometimes, that focus is achieved, I don't trust that little beep. It means the camera thinks it's focused, but its not allways true.
I agree with your point. I use zone MF myself when I'm doing hyperfocal work in landscapes or street shooting.
However, my understanding is that the split/micro prism will only come in useful if your subject is dead center, and you don't do any FLR. If one is going to do MF on an off-center subject using the matte part of the focussing screen, then wouldn't it defeat the purpose of having the center prism? The original matte screen would suffice too.
Wenyao
RoyPertchi wrote:
Nutek,
AF works great for me for one style of shooting; moving quickly and grabbing shots I see happening arround me, action, street photography. But I do a lot of tripod work where I'll spend 2, 3, 4 hours setting up a shot. It's very possible there is nothing with contrast in the shot on a focus point, or the light level can sometimes be quite low until my strobes fire (location shooting of architectural interiors). I hate not being able to be SURE that the focus is sharp, befor I break down the set up and leave. To verbalize why I want one, and why I have said so many times since I got may camera about 5 months ago, it's for peace of mind. The have been several occasions when I got home to my PC and reviewed images and found an shot that would be perfect if it were only sharp. Somed days, i don't want a few "keepers" out of hundreds. I MUST have all 3 shots taken in 9 hours to be perfect. So, I would love to have a way to confirm focus visually in the lens. Even with my faster paced shooting, I still want to see for myself, sometimes, that focus is achieved, I don't trust that little beep. It means the camera thinks it's focused, but its not allways true....Show more →
So if you're using Zeiss lenses, I believe you are going to have to use stop-down metering right? If that's the case, the prism will only be useful for aperture values of less than f5.6 or so, as if you stop down more than that, you woudn't even be able to see much light in the viewfinder anymore.
EDIT: OK, I'm wrong here. You still can MF while the lens is fully open, and only stop down when you want to take the picture.
But my point is: at f5.6 or larger aperture (i.e. smaller f-number), your depth-of-field is going to be pretty shallow for most lenses (less the wide-angles) in many types of shooting situations. So my basic question again: how do you compose for an off-center subject then?
1) If you use FLR, then oops, you'll get focussing errors due to the thin DOF.
2) If you use the matte part of the focussing screen, then why do you need the prism then?
I have had a Canon Magnifer S previously but sold it, because I found that most of the time my subjects are not directly-centered in the frame, so precise MF there is no help at all. If you're shooting a lot of center-framed macro shots, yes, I would agree that Angle Finder C or Magnifier S or split/micro prism would help alot, but if you're not, then....?
wenyao
carsonwick wrote:
Pretty much for 20D people that want to use Zeiss lenses. I use an angle finder c for manual focusing.