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Archive 2009 · Lens adapter: AF Confirm or not?

AndreaPress
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p.1 #1 · Lens adapter: AF Confirm or not?

I would like to get two adapter: OM and Contax to EOS.
Please can somebody explaine how the AF confirm version works?

I would like to understand if the AF confirm is precise and if I can choose the specific point to use.

Anyway what do you suggest? The chipped version or the standard version (maybe with an EE-S focusing screen)?

Thanks!!

Edited on Oct 30, 2009 at 03:35 PM · View previous versions

Oct 30, 2009 at 01:44 PM

rhorta
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p.1 #2 · Lens adapter: AF Confirm or not?

I'm using a number of AF-confirm adapters from BIG-IS, both older non-programmable and the later programmable type.

Up to f/2 (or f/1.7 / 1.8 depending on the lens), I am getting very accurate results, even close to MFD, but the rate drops off using apertures like f/1.4 or even f/1.2 especially near MFD and I need to use "bracket" focus.

As the range gets bigger, the easier it gets. At a couple of meters distance even f/1.2 isn't as big an issue anymore. However I prefer LV for wide open shots on very fast lenses especially anywhere near mfd.

In short, I'd get the chipped type, which IMHO gives you a little more versatility.

Ruy

Edited on Oct 30, 2009 at 06:24 PM · View previous versions

Oct 30, 2009 at 02:02 PM

rachp
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p.1 #3 · Lens adapter: AF Confirm or not?

I have adapters with and without focus confirmation. The way I see it, it is nice to have but not perfectly accurate. Yes, you can select your camera's focus point to use. I would say if you are not bothered by the extra cost of the chip, then get it.

Oct 30, 2009 at 05:01 PM

philber
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p.1 #4 · Lens adapter: AF Confirm or not?

I use AF confirm adapters from HappyPageHK. Focus confirm works at least as well as on Canon lenses, and as for Canon lenses, you need to micro-adjust if you have 50D/5DII/7D

Oct 30, 2009 at 10:14 PM

jcolwell
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p.1 #5 · Lens adapter: AF Confirm or not?

I'm generally a 'not' person. Many of my alt adapters have focus confirmation chips, but as rach says, they're not always accurate, and I find that I really don't look for the FC light when I'm using them. I tend to use my alts in two ways: (i) wide open for isolating the subject from the background (esp. for fast ones like the Planar 85/1.4), or (ii) stopped down to f/8 or smaller for scale focus landscapes and etc. (esp. for the Distagon 28/2.8). Either way, the FC chip doesn't help me very much.

Oct 31, 2009 at 12:01 AM

gasrocks
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p.1 #6 · Lens adapter: AF Confirm or not?

I find they hurt more than help.

Oct 31, 2009 at 12:46 AM

AndreaPress
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p.1 #7 · Lens adapter: AF Confirm or not?

Hi, many thanks for the replies.
I should try a chipped adapter, anyway after reading your comments, I think that a dedicated focusing screen for fast lenses will help me especially If I have to adjust the focus manually without trusting the AF confirm.

I'm happy to read that is possible to choose a specific AF point

this is good!

Thanks!!

Oct 31, 2009 at 12:51 AM

dave chilvers
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p.1 #8 · Lens adapter: AF Confirm or not?

I have a mixture of standard, AF confirm and AF confirm with exif and micro adjust.

You just can`t beat live view period but some of my lenses after micro adjust( through the adapter) are pretty close to live view and using f8 or around that I can trust the confirm light. Using large apertures (1.8, f2) sees me always checking with live view. Once you try out the AF confirm adapters you`ll see that sometimes after getting the AF confirm light/beep and checking with live view you need a slight tweek although DOF might well have taken care of it. On the other hand when you live view a scene and then switch back to normal view the AF light will always light.
It will depend on focal length, I find that up to 35mm on the subjects that I shoot judging the DOF is just like the old days but once you hit 50mm and above in general live view is the way to go because quite frankly what you see through the viewfinder doesn`t usually match what the sensor is seeing. The Eg-s screen helps but the trouble is that the better the lens you are using the bigger your expectations are and small deviations away from perfect focus really shows.

Oct 31, 2009 at 09:40 AM

wyan
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p.1 #9 · Lens adapter: AF Confirm or not?

If you are using 5D (5D2), I would recommend you to save the money and buy yourself a Canon EE-S (EG-S) focusing screen instead. I use Distagon 35/1.4 with AF confirm chips at f1.4 and f2 and it doesn't help. With EG-S screen, I have 75% keeper rate.

Also, the AF confirm chip sometimes may give you wrong exposure.

Hope this helps.

Oct 31, 2009 at 02:47 PM

AndreaPress
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p.1 #10 · Lens adapter: AF Confirm or not?

wyan wrote:
If you are using 5D (5D2), I would recommend you to save the money and buy yourself a Canon EE-S (EG-S) focusing screen instead. I use Distagon 35/1.4 with AF confirm chips at f1.4 and f2 and it doesn't help. With EG-S screen, I have 75% keeper rate.

Also, the AF confirm chip sometimes may give you wrong exposure.

Hope this helps.

Hi Wyan,
this is really useful because I've the 5D "Classic" and I'm thinking to buy a Zeiss 35mm f/1.4 so your comment have helped me a lot.

For now I'll get the EE-S and regarding the adapter I'm thinking to purchase the standard version.
How big is the performance variation between different adapters?
I'm thinking to get it from a local manufacturer.

Sorry but regarding the EE-S, do you use it only with fast lenses or it can be used with any lens?
I've red something about luminosity problems in low light conditions.

Thanks!!
Andrea

Oct 31, 2009 at 03:12 PM

wyan
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p.1 #11 · Lens adapter: AF Confirm or not?

Andrea,

With EE-S screen, your viewfinder will be about 1 stop darker. That won't be much a problem if you mainly use F2.8 or larger aperture. If you are using f11 something for landscapes etc, it won't be a problem either.

The adapters these days are usually good enough. You may simply try it at your local shops.

Wenye

AndreaPress wrote:
wyan wrote:
If you are using 5D (5D2), I would recommend you to save the money and buy yourself a Canon EE-S (EG-S) focusing screen instead. I use Distagon 35/1.4 with AF confirm chips at f1.4 and f2 and it doesn't help. With EG-S screen, I have 75% keeper rate.

Also, the AF confirm chip sometimes may give you wrong exposure.

Hope this helps.

Hi Wyan,
this is really useful because I've the 5D "Classic" and I'm thinking to buy a Zeiss 35mm f/1.4 so your comment have helped me a lot.

For now I'll get the EE-S and regarding the adapter I'm thinking to purchase the standard version.
How big is the performance variation between different adapters?
I'm thinking to get it from a local manufacturer.

Sorry but regarding the EE-S, do you use it only with fast lenses or it can be used with any lens?
I've red something about luminosity problems in low light conditions.

Thanks!!
Andrea

Oct 31, 2009 at 03:45 PM


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