Kenko 1.4x Pro 300 DGX and focus issues.

I am just starting my foray into macro shooting. Gear: 6D, EF 100mm f/2.8 USM macro, Kenko 1.4x Pro 300 DGX, Canon 25mm ET II, 2 270EX II and home-made bracket, YN-622 stuff as needed.

I am having real trouble, but only at macro distances, withthe AF when the Kenko 1.4X is mounted. It works fine in bright sunshine, not so much in day-time shadows. It works indoors pretty much only when in the direct light of what ever lights I have on.

The TC works fine, in any light (within reason) at normal shooting distances, and with my other lenses. I've used it on the 70-200 f/4 IS and, the 100-400L (MF only), and it works as expected.

Is this normal behavior for a lens/TC combo at macro distances? The bare lens focuses well in the same light the lens/TC combination seems to struggle in. Do I need to mount a AAA-cell flashlight in order to work (hand-held) with the TC?

GeoKras1989 wrote in post #17667133
I am just starting my foray into macro shooting. Gear: 6D, EF 100mm f/2.8 USM macro, Kenko 1.4x Pro 300 DGX, Canon 25mm ET II, 2 270EX II and home-made bracket, YN-622 stuff as needed.

I am having real trouble, but only at macro distances, withthe AF when the Kenko 1.4X is mounted. It works fine in bright sunshine, not so much in day-time shadows. It works indoors pretty much only when in the direct light of what ever lights I have on.

The TC works fine, in any light (within reason) at normal shooting distances, and with my other lenses. I've used it on the 70-200 f/4 IS and, the 100-400L (MF only), and it works as expected.

Is this normal behavior for a lens/TC combo at macro distances? The bare lens focuses well in the same light the lens/TC combination seems to struggle in. Do I need to mount a AAA-cell flashlight in order to work (hand-held) with the TC?

Heya,

It can be normal, at macro distance, especially through a TC, there's very little light for the contrast detect AF to work from, so it's hard (even for a 6D's center point) since you are physically focusing with an F4 base lens (F2.8 -1 stop for the 1.4x TC). Again, at macro distance there's less light than you think to work with, but on top of that, adding a TC drops light too for AF before aperture closes down even.

I use a LED ring light in low light (and in the straight dark) on the front of my lens to allow AF to work in low light.

Very best,

Thanks. Did you really mean contrast-detect AF? I haven't tried that. When I use AF for macro, it has always (for a whole 3-4 days!) been phase-detect.

GeoKras1989 wrote in post #17668156
Thanks. Did you really mean contrast-detect AF? I haven't tried that. When I use AF for macro, it has always (for a whole 3-4 days!) been phase-detect.

Heya,

Yeap, contrast via the view finder. Phase is live view, right? I rarely use Live View for the actual shots (for my macro). If I were doing plants from a tripod, I'd probably use Live View because it's nicer to see it and easier. But I'm constantly moving and hand holding at weird angles, so I use the view finder (can't see my live view in the sun anyways without shading it, which I do just to see the histogram when looking at my ambient light exposure values).

I use a Kenko 2.0x Pro 300 DGX TC, same family as yours, and it definitely affects AF abilities with the light loss (this one gobbles 2 stops of light, taking my F3.5 to greater than 5.6 and makes it hunt unless in good light, so I generally just use manual focus here anyways by moving the pre-focused lens over the subject slowly and taking the image when I think I'm where I want to be on the subject).

Very best,

I figured one of us was confused. I believe contrast is LV, and phase is TTL AF. Not that it really matters, we are both using the viewfinder/lens for AF.

I am happy to find out that the TC, together with macro distances, is likely causing my completely normal AF problems. I did reset my rig, but I am waiting to empty a few plastic butter bowls (diffusers), before I test again. I did spend a few more hours practicing yesterday. I took your advice and shut off the HSS. That was actually ruining my sharpness because the flash has to last longer, instead of a near-instant burst. I also practiced a bit with just the 100. I am a bit unsteady with the 100 and 1.4x yet.

GeoKras1989 wrote in post #17668165
I figured one of us was confused. I believe contrast is LV, and phase is TTL AF. Not that it really matters, we are both using the viewfinder/lens for AF.

I am happy to find out that the TC, together with macro distances, is likely causing my completely normal AF problems. I did reset my rig, but I am waiting to empty a few plastic butter bowls (diffusers), before I test again. I did spend a few more hours practicing yesterday. I took your advice and shut off the HSS. That was actually ruining my sharpness because the flash has to last longer, instead of a near-instant burst. I also practiced a bit with just the 100. I am a bit unsteady with the 100 and 1.4x yet.

Heya,

Maybe I'm backwards with contrast/phase, sorry about that!

I would try to do more without a TC for right now and just get a hang of using the naked 100 since it already does 1:1 nicely from a good distance, and your lights and just develop your lighting and technique of holding/composing. Then add a TC and/or Ext Tubes when you feel you need more magnification for super tiny things.

Very best,

I used to use my kenko 1.4 on my macro with a full set of tubes, but I only MF it by moving in and out because I found it to be easier

I do have the older non usm macro though, and I use a flash that projects the AF assist(although I'm not sure if it would even help)

I know I've suggested it to you before, but I'll do it again...manual focus for macro is much easier than auto focus

DreDaze wrote in post #17668206
I used to use my kenko 1.4 on my macro with a full set of tubes, but I only MF it by moving in and out because I found it to be easier

I do have the older non usm macro though, and I use a flash that projects the AF assist(although I'm not sure if it would even help)

I know I've suggested it to you before, but I'll do it again...manual focus for macro is much easier than auto focus

Thanks. I do use MF on smaller object that I want to get really close to. I just set the lens to MFD & MF, and move in and out to find focus. For auto-focus, I may be very close, but not 1:1. The extra distance seems to make AF work better (more light?).