[BruceBanner]

Just a quick question. During my month of 'Manual Focus only' I note that the AF lenses I own (DFA100 and FA50mm), when placed in MF mode (via the lever on the body of the K-1), I can still use the AF Point system to assist in focus points. For example, I can have SEL mode (single point) selected and shift the focus point to 1 up and 2 to the right for example, and then when I focus using the focus ring on the lens it makes a beep/highlights red when focus on that point is achieved.

But these lens cannot do CIF.

So when I use an old MF lens only such as the Pentax-A SMC 50mm 1.7, I can now toggle the lever on the K-1 to AF mode and select CIF via the menu, however I only get a single centre point 'dot/square' as the focus point which means CIF works but ONLY on the centre of the frame/image.

This has now got me wondering how the Samyang 85/1.4 and 135/2 work, do they follow a scenario closer to the DFA100 in that I can choose a focus point or more like the 50mm 1.7.

Perhaps a better lens to pursue would be an AF lens that has a AF/MF switch on it, perhaps this allows you the best of both worlds, CIF at a point that isn't centre dot/square?!

Can anyone confirm this?

TIA!

Bruce

[stevebrot]

Perhaps a better lens to pursue would be an AF lens that has a AF/MF switch on it, perhaps this allows you the best of both worlds, CIF at a point that isn't centre dot/square?!

Can anyone confirm this?

CIF only works with the center point, regardless of how you get there and AF must be enabled on the bpdy. This was a thread on this topic some time back and I confirmed with my Sigma 17-70/2.8-4 (C) at that time how it works (AF turned off at lens...AF turned on at body).


Steve

[stevebrot]

This has now got me wondering how the Samyang 85/1.4 and 135/2 work, do they follow a scenario closer to the DFA100 in that I can choose a focus point or more like the 50mm 1.7.

Both of those lenses are KA mount and will act the same as your A 50/1.7 and other manual focus lenses. Your D FA 100/2.8 has screw-drive AF and lacks in-body focus motor and cannot be used with CIF. Some might suggest masking the "data" contact on the mount, but turning the focus ring with the AF pawl engaged risks damage to both camera and body.

What is your use case for CIF?


Steve

[BruceBanner]

CIF only works with the center point, regardless of how you get there and AF must be enabled on the bpdy. This was a thread on this topic some time back and I confirmed with my Sigma 17-70/2.8-4 (C) at that time how it works (AF turned off at lens...AF turned on at body).


Steve

I'm aware of CIF only being utilised when the camera body is in AF mode, I just have no lens to test that has a AF/MF switch. I wondered because when I use my DFA100 and FA50 in MF mode, you can have the focus point detection anywhere you like, you're not stuck with it being centre point like I am with the A 50/1.7. This got me thinking... if I owned a AF lens therefore that had a AF/MF switch, if I then put the body in AF mode, and the lens in MF mode, would the directional pad select focus points work normally (like they can be in MF mode) and therefore I could actually also CIF from a point off centre?

But if as you say you've tested it with the Sigma 17-70 and did as I ask (AF on body, AF off on lens) and confirm that when CIF is enabled in the menu, that you are still only given a single centre point for the focus point then that answers my question.

Both of those lenses are KA mount and will act the same as your A 50/1.7 and other manual focus lenses. Your D FA 100/2.8 has screw-drive AF and lacks in-body focus motor and cannot be used with CIF. Some might suggest masking the "data" contact on the mount, but turning the focus ring with the AF pawl engaged risks damage to both camera and body.

What is your use case for CIF?


Steve

Yeh i didn't want to go messing with contacts, I think (once) I managed to get CIF working on a AF lens by not turning the lens all the way around and getting that satisfying 'click', it kinda worked but exposure was way off, so yeh not fussed about that. I'm fine with not having CIF working on certain lenses and only on others. I have just simply noticed that the when using MF on the FA50 and DFA100, it's real nice to be able to have a SEL mode and single focus point off centre somewhere to help you nail that focus. I wondered if the Samyangs would give that also but I thought I would be clutching at straws.

CIF I could use for a heap of things really. Thus far my month without using AF is going rather well and I'm enjoying the process. I could see me ditching AF for all those things that stand still, where I need AF would be moving stuff, and in AF.C mode likely. CIF would possibly be the next best thing in MF world to being able to do that, it would be neat if the capture could fire from a point that wasn't just the centre however... ce la vie.

[stevebrot]

if I then put the body in AF mode, and the lens in MF mode, would the directional pad select focus points work normally (like they can be in MF mode) and therefore I could actually also CIF from a point off centre?

No, if the lens is detected as manual focus (AF turned off on the lens), the rules are per manual focus with the AF point being limited to center. CIF is simply the happy coincidence of manual focus AF confirm and AF-S (focus priority) and is not something magical. I have been doing CIF for over a decade and there is no way to do it with other than with center-point focus.


Steve

[BruceBanner]

No, if the lens is detected as manual focus (AF turned off on the lens), the rules are per manual focus with the AF point being limited to center. CIF is simply the happy coincidence of manual focus AF confirm and AF-S (focus priority) and is not something magical. I have been doing CIF for over a decade and there is no way to do it with other than with center-point focus.


Steve

Thanks for confirming this Steve.

[angerdan]

I'd like to add for other interested readers the decryption and official name of CIF:

Catch-in Focus

---

Last edited by angerdan; 04-22-2018 at 06:10 AM. Reason: Catch-in Focus

[stevebrot]

I'd like to add for other interested readers the decryption and official name of CIF:

Catch-in Focus

Also known as focus trapping. Thanks for providing the full term as it is used in the camera manual.


Steve