How to manually focus my dSLR

hyakuhei · Jun 16, 2007

Hi All,
I have very recently gotten interested in phtotography and by way of dipping my toe in the water I bought a Canon 300D earlier this week.

Like many EOS owners on a budget (I'm a student) I have picked up an older M42 lens and adapter. (I have others but thats off topic).

Obviously, I can't use AF so my question is simple, how can I acheive a good focus with a 300D ? Is it possible to fit a split prism to the view finder?

I'm used to manual focus on my current film SLR, I'm not sure how hard unassisted(no magic optics) manual focus will be as my camera hasn't actually arrived yet but I'd be interested to know if any of you kind folks knows solutions or techniques to use in this kind of situation...

hyakuhei · Jun 16, 2007

Sorry, I posted this in the wrong forum, could admin please bump it to the beginners section please? - Thanks

Digital Matt · Jun 16, 2007

You can buy a micro or split prism focus screen for the 300D from Katz Eye.

http://www.katzeyeoptics.com/item--...or-the-Canon-300D-DRebel-Kiss--prod_300D.html

The 300D has a small viewfinder, which is probably a bit smaller than what you are used to. I won't kid you, it's not fun or easy to manually focus. I have really great eyes, and I often have trouble with a 20D. The focus screen might help you. Another member on here, ksmattfish uses one of those screens with a 20D. Hopefully he'll see this and come around. If not, you can PM him.

hyakuhei · Jun 17, 2007

Great thanks - I'm researching now!

ksmattfish · Jun 17, 2007

I use the Katz Eye split screens in my 20D's, and I like them, although because of the small viewfinder it's still harder than with your average 35mm SLR. Another company that makes focusing screens is Haoda.

http://haodascreen.com

jon_k · Jun 17, 2007

I hate to sound stupid here, but what is a focusing screen? Where exactly does it fit, and how does it help you achieve better focus? I can't find the answers on the internet.

I've found with luck I can achieve better focus manually than my camera can. Although maybe this is because the Olympus E-500 only does focus based on 3 points. Maybe it's because I get to focus on what I want to bring attention to.

Would a focus screen help me? I see they have one for my camera.

[edit]
I understand better now
"In the past, focus screens had precision ground microprism/split-screen focusing
indicators, from which you could clearly see if the subject was in focus or not.
When focused properly, the two halves in the split-screen join and the microprism
pattern disappears. Wonders of optics."
I remember using a film SLR and it was a cakewalk to focus manually. Man, what are modern cameras doing?

I also looked in to my camera body and I see the location of the focus screen. It's right there at the top of the camera body. It doesn't look like it's suppose to be removed. How do you guys put these things in there? Take it to a camera shop and have a professional replace it with one of these after market screens? I certainly wouldn't want to hack around on my camera.

hyakuhei said:
could admin please bump it to the beginners section please? - Thanks

To me this sounds pretty advanced.

ksmattfish · Jun 18, 2007

jon_k said:
It doesn't look like it's suppose to be removed. How do you guys put these things in there? Take it to a camera shop and have a professional replace it with one of these after market screens? I certainly wouldn't want to hack around on my camera.

Some cameras are designed so that it's easy to switch out the focusing screens. I'm sure Canon says that the focusing screen in the Rebel, 20D, 30D, etc... isn't meant to be switched out since they don't offer any other screen options themselves. Installation instructions come with the screens. I've done 2 20D's, and it was pretty easy. If you don't want to mess with it yourself anyplace that does camera repair could do it.

Alex_B · Jun 18, 2007

jon_k said:
it's suppose to be removed. How do you guys put these things in there? Take it to a camera shop and have a professional replace it with one of these after market screens? I certainly wouldn't want to hack around on my camera.

Not sure about your camera, but for many cameras Canon sells different screens as well and they are fairly easy to exchange.

Of course you can always ask people at a shop to do it for you if you are unsure. Canon itself will charge you for doing it.

To me this sounds pretty advanced.

Hm, that depends ... it is a quite basic thing in the SLR world I would say.

Garbz · Jun 18, 2007

There are aftermarket screens sold for all Nikon and Canon cameras, just not always by the said manufacturers.

Doesn't canon give some kind of focus indicator? Even in manual mode on my D200 the autofocus scans the centre focus point and when it is in focus a green light comes on in the viewfinder.

bakuretsu · Jun 19, 2007

jon_k said:
I hate to sound stupid here, but what is a focusing screen? Where exactly does it fit, and how does it help you achieve better focus? I can't find the answers on the internet.

If you take the lens off of your DSLR (or SLR), hold it upright, and look straight into the open chamber, the focusing screen will be oriented horizontally along the top and you will see its reflection in the mirror. Tipping the camera back, away from you, you will then see the screen itself.

Most DSLRs these days do not ship with what are typically called "split prizm" or "ground glass" screens where there is actually a focusing aid; because DSLRs are especially reliant on their autofocus systems, manufacturers don't expect most users to need focus assistance.

What a classic focusing screen does is actually allow you to see when the center is in focus with less guesswork. Typically there is a circle in the center of the screen, which is divided in half. One half of the circle has a prizm pattern or other refractive etching and the other half does not. When that area of the image is in focus, the two halves will look nearly identical.

I'm not completely sure how these devices work, optically, but once you've used one you realize how helpful they are when you're manually focusing. A split prizm focusing screen would have been standard issue on virtually all SLR cameras during the time when manual focus was still very much part of the game, but today autofocus sytems have improved a great deal and most people can get away without them.

I've been waiting for a focusing screen that fits the 5D to become available for a while now, simply because manual focus is sometimes faster and more convenient, but not always as accurate.

Also, to Garbz, yes, Canon does give you a focus indicator. Normally when using AF, the active autofocus point in my viewfinder will blink to tell me which one is active, and when focus is achieved, a green light comes on.

When manually focusing, the AF point doesn't blink when the shutter button is half depressed as it does in AF, but when focus is achieved on the point you've selected, the AF point then blinks red. So you do get a bit of help from the AF system even when you're manually focusing, which is what I do with my macro lens.

DeadEye · Jun 20, 2007

bakuretsu said:
If you take the lens off of your DSLR (or SLR), hold it upright, and look straight into the open chamber, the focusing screen will be oriented horizontally along the top and you will see its reflection in the mirror. Tipping the camera back, away from you, you will then see the screen itself.

Most DSLRs these days do not ship with what are typically called "split prizm" or "ground glass" screens where there is actually a focusing aid; because DSLRs are especially reliant on their autofocus systems, manufacturers don't expect most users to need focus assistance.

What a classic focusing screen does is actually allow you to see when the center is in focus with less guesswork. Typically there is a circle in the center of the screen, which is divided in half. One half of the circle has a prizm pattern or other refractive etching and the other half does not. When that area of the image is in focus, the two halves will look nearly identical.

I'm not completely sure how these devices work, optically, but once you've used one you realize how helpful they are when you're manually focusing. A split prizm focusing screen would have been standard issue on virtually all SLR cameras during the time when manual focus was still very much part of the game, but today autofocus sytems have improved a great deal and most people can get away without them.

I've been waiting for a focusing screen that fits the 5D to become available for a while now, simply because manual focus is sometimes faster and more convenient, but not always as accurate.

Also, to Garbz, yes, Canon does give you a focus indicator. Normally when using AF, the active autofocus point in my viewfinder will blink to tell me which one is active, and when focus is achieved, a green light comes on.

When manually focusing, the AF point doesn't blink when the shutter button is half depressed as it does in AF, but when focus is achieved on the point you've selected, the AF point then blinks red. So you do get a bit of help from the AF system even when you're manually focusing, which is what I do with my macro lens.

I have read this thread with great interest as I have been using FD prime lens with a fd to eos adaptor to do marco work and wishing for a manual assist screen to fit the XTI to lesson to guess work on when its tack sharp. So after reading the thread I thought to myself have I just spaced out and not noticed the point flash! I got the camera out and put the switch on the 50mm to manual twisted the ring and sure enough the point will flash when task sharp is achived.

So I set up a cig to shoot with the fd/eos adaptor_no glass adaptor and a 135mm prime. Twisted the ring and get no flash from point:x I tryed and tryed focus confirm just wont work with the fd lens. Here is a picture of the subject well focused. Why no confirm with this combo?

tempra · Jun 21, 2007

you could get an M42 adapter with the electronic connections for EOS which makes the focus confirmation light work and apparently is fine for ETTL as well - not used one myself so don't know how effective they are http://cgi.ebay.co.uk/E-TTL-AF-Conf...ryZ30059QQssPageNameZWDVWQQrdZ1QQcmdZViewItem

DeadEye · Jun 21, 2007

tempra said:
you could get an M42 adapter with the electronic connections for EOS which makes the focus confirmation light work and apparently is fine for ETTL as well - not used one myself so don't know how effective they are http://cgi.ebay.co.uk/E-TTL-AF-Conf...ryZ30059QQssPageNameZWDVWQQrdZ1QQcmdZViewItem

Ok thank you. A chip is needed for the af confirm

sabbath999 · Jun 21, 2007

I wonder if the installation of one of these screens would void the warranty?

jon_k · Jun 22, 2007

bakuretsu said:
Typically there is a circle in the center of the screen, which is divided in half. One half of the circle has a prizm pattern or other refractive etching and the other half does not. When that area of the image is in focus, the two halves will look nearly identical.

Ahh, I know exactly what you mean!

My dad had a film SLR that required manual focus, and there was a semi circle split in to two semicircles. One would be in focus, the other would stay blurry until you obtained focus. It made focus a breeze! I'm really saddened the new DSLR's don't do this.

So these screens are what can accomplish this? They've got the prism required to obtain the same effect? If so, I'll seriously consider getting one and having a shop retrofit my camera. Warranty voids or not, you could always take your camera back to the shop and have it fixed back to the old screen if you wanted to claim warranty. ;-)