catch in focus

**TER-OR** · 03-28-2012, 08:00 AM

I think some of it is DOF and some is figuring out exactly where the camera is focusing. IIRC the CIF fires as soon as there is a focus confirmation which may be at the very front or rear of your subject depending on which way you're rotating focus. Fire a couple shots in rolling focus to be sure.

The worst I've noticed are the low-contrast shots, as mentioned above.

I have a bunch of CIF shots to upload to Flickr from a trip to the Anderson Japanese Gardens in Rockford last summer. My wife had the K-10 with 10-17 Fisheye and I had an M-50. We both got some good shots, I should sort thru them before they're a year old...

**Canada_Rockies** · 03-28-2012, 09:13 PM

CIF will work fine if the camera and lens allow it. I don't think the aperture setting will matter unless you are using an M42 lens that you have to shoot stopped down. CIF will not work when AF will not work - it's the same focus detecting sensor . I find that CIF works just fine even with my M400/5.6 - and I can have it set to f/11 which will only affect things when the shutter actually releases and the lens stops down. You do need to make sure that the subject has enough contrast. As the light gets poorer, the contrast must increase so that the sensor has something to work with.

If you are using an A lens, then it helps to set the focus points to the centre focus point only. There are a few computer cycles involved in deciding which point to use.

RioRico · 03-29-2012, 02:36 AM

Originally posted by Canada_Rockies

CIF will work fine if the camera and lens allow it. I don't think the aperture setting will matter unless you are using an M42 lens that you have to shoot stopped down.

I corrected my previous post. Yes, the ~f/8 cutoff applies to screwmount or T2-adapted or other manual-aperture lenses, anything without a working camera-to-lens aperture link. I have a zillion such lenses so I tend to think of those as standard, with the ~f/8 cutoff as a norm.

Quote:

If you are using an A lens, then it helps to set the focus points to the centre focus point only. There are a few computer cycles involved in deciding which point to use.

I only have a couple A-type lenses and I haven't used them much so I didn't notice this. Thanks! Now I can use them intelligently in more diverse situations. I usually try to stay center-weighted anyway. Back in the day, that was the best there was, and I'm still comfortable there.

Na Horuk · 04-07-2012, 08:00 AM

Hey, I have a question about CiF. It cannot be used with the DA L lenses, right? What about their DA counterparts? And what about the DA 35mm f2.4?

joe.penn · 04-07-2012, 08:48 AM

Originally posted by Na Horuk

Hey, I have a question about CiF. It cannot be used with the DA L lenses, right? What about their DA counterparts? And what about the DA 35mm f2.4?

Correct
No
No

When you are talking about DA lenses, I am assuming you are not talking about DA* lenses - DA* lenses with SDM can be used with CIF as the AF drive is disconnected at the lens which in return tells the camera body that the lens is in MF mode. The issue with the DAL lenses is that to disable AF it has to be done at the body and thus breaks the internal plumbing of the CIF feature. This is one thing that keeps me away from some of the newer Tamron glass as those too can't be used with CIF...

Na Horuk · 04-07-2012, 09:08 AM

Originally posted by joe.penn

When you are talking about DA lenses, I am assuming you are not talking about DA* lenses - DA* lenses with SDM can be used with CIF as the AF drive is disconnected at the lens which in return tells the camera body that the lens is in MF mode. The issue with the DAL lenses is that to disable AF it has to be done at the body and thus breaks the internal plumbing of the CIF feature. This is one thing that keeps me away from some of the newer Tamron glass as those too can't be used with CIF...

Ah, thank you very much. Too bad.

03-29-2012, 02:36 AM	#18
RioRico Veteran Member Join Date: Jun 2008 Location: Limbo, California Posts: 11,263	Originally posted by Canada_Rockies CIF will work fine if the camera and lens allow it. I don't think the aperture setting will matter unless you are using an M42 lens that you have to shoot stopped down. I corrected my previous post. Yes, the ~f/8 cutoff applies to screwmount or T2-adapted or other manual-aperture lenses, anything without a working camera-to-lens aperture link. I have a zillion such lenses so I tend to think of those as standard, with the ~f/8 cutoff as a norm. Quote: If you are using an A lens, then it helps to set the focus points to the centre focus point only. There are a few computer cycles involved in deciding which point to use. I only have a couple A-type lenses and I haven't used them much so I didn't notice this. Thanks! Now I can use them intelligently in more diverse situations. I usually try to stay center-weighted anyway. Back in the day, that was the best there was, and I'm still comfortable there. Last edited by RioRico; 03-29-2012 at 02:41 AM.

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03-28-2012, 08:00 AM	#16
TER-OR Site Supporter Join Date: Apr 2009 Location: Dundee, IL Photos: Gallery \| Albums Posts: 6,699	I think some of it is DOF and some is figuring out exactly where the camera is focusing. IIRC the CIF fires as soon as there is a focus confirmation which may be at the very front or rear of your subject depending on which way you're rotating focus. Fire a couple shots in rolling focus to be sure. The worst I've noticed are the low-contrast shots, as mentioned above. I have a bunch of CIF shots to upload to Flickr from a trip to the Anderson Japanese Gardens in Rockford last summer. My wife had the K-10 with 10-17 Fisheye and I had an M-50. We both got some good shots, I should sort thru them before they're a year old...

03-28-2012, 09:13 PM	#17
Canada_Rockies Loyal Site Supporter Join Date: Nov 2007 Location: Sparwood, BC, Canada Photos: Gallery \| Albums Posts: 12,385	CIF will work fine if the camera and lens allow it. I don't think the aperture setting will matter unless you are using an M42 lens that you have to shoot stopped down. CIF will not work when AF will not work - it's the same focus detecting sensor . I find that CIF works just fine even with my M400/5.6 - and I can have it set to f/11 which will only affect things when the shutter actually releases and the lens stops down. You do need to make sure that the subject has enough contrast. As the light gets poorer, the contrast must increase so that the sensor has something to work with. If you are using an A lens, then it helps to set the focus points to the centre focus point only. There are a few computer cycles involved in deciding which point to use.

04-07-2012, 08:00 AM	#19
Na Horuk Veteran Member Join Date: Feb 2012 Location: Slovenia, probably Photos: Gallery \| Albums Posts: 11,186	Hey, I have a question about CiF. It cannot be used with the DA L lenses, right? What about their DA counterparts? And what about the DA 35mm f2.4?

04-07-2012, 08:48 AM	#20
joe.penn Veteran Member Join Date: Mar 2011 Location: Maryland (Right Outside Washington DC) Photos: Gallery \| Albums Posts: 2,902	Originally posted by Na Horuk Hey, I have a question about CiF. It cannot be used with the DA L lenses, right? What about their DA counterparts? And what about the DA 35mm f2.4? Correct No No When you are talking about DA lenses, I am assuming you are not talking about DA* lenses - DA* lenses with SDM can be used with CIF as the AF drive is disconnected at the lens which in return tells the camera body that the lens is in MF mode. The issue with the DAL lenses is that to disable AF it has to be done at the body and thus breaks the internal plumbing of the CIF feature. This is one thing that keeps me away from some of the newer Tamron glass as those too can't be used with CIF...

04-07-2012, 09:08 AM	#21
Na Horuk Veteran Member Join Date: Feb 2012 Location: Slovenia, probably Photos: Gallery \| Albums Posts: 11,186	Originally posted by joe.penn When you are talking about DA lenses, I am assuming you are not talking about DA* lenses - DA* lenses with SDM can be used with CIF as the AF drive is disconnected at the lens which in return tells the camera body that the lens is in MF mode. The issue with the DAL lenses is that to disable AF it has to be done at the body and thus breaks the internal plumbing of the CIF feature. This is one thing that keeps me away from some of the newer Tamron glass as those too can't be used with CIF... Ah, thank you very much. Too bad.

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