[jerryleejr]

Been using my 100mm macro on my K1MKii it works great gives awesome results but I’ve never used more than the 1st 3rd of lens travel on anything I’ve taken a picture of. I even tried to focus on something with some distance from me and the autofocus brought it right back to the first 3rd TAC sharp and great photo. So what requires cranking it all the way out what am I missing?


JJ

[bertwert]

I think I'm missing what you're asking here... with it all the way retracted, you're focusing at infinity (so far away things), and all the way extended you're focusing at the minimum focus distance - this has a magnification of 1:1, so objects are projected their actual size on the sensor (ie, 2mm on object covers 2mm of the sensor), things are going to pretty close here.

[AstroDave]

Have you tried focusing on something really close - that's what macro lenses are for. And that means just a few inches in front of your camera. That is where much of the lens travel occurs.

Postage stamps make good macro test objects. Get it to fill as much of your frame as you can. On K-1, a typical US commemorative stamp should nearly fill the frame.

[MikeMcE]

Coins and stamps work great
Hang up and DRIVE!

[jerryleejr]

Here’s a sample, still didn’t have the lens extended very much…

100mm mounted on K1MKii - PentaxForums.com

[UncleVanya]

Been using my 100mm macro on my K1MKii it works great gives awesome results but I’ve never used more than the 1st 3rd of lens travel on anything I’ve taken a picture of. I even tried to focus on something with some distance from me and the autofocus brought it right back to the first 3rd TAC sharp and great photo. So what requires cranking it all the way out what am I missing?


JJ

1:1 capability means that at minimum distance the object will be the same size as the image on the sensor. A 24mm object will fill the sensor top to bottom.

My suggestion. Turn autofocus off. Set lens to maximum magnification and minimum distance. Take the camera and set it in liveview. Find something small. Get closer and closer and closer. Eventually it will resolve in focus. It will be quite close.

[jerryleejr]

1:1 capability means that at minimum distance the object will be the same size as the image on the sensor. A 24mm object will fill the sensor top to bottom.

My suggestion. Turn autofocus off. Set lens to maximum magnification and minimum distance. Take the camera and set it in liveview. Find something small. Get closer and closer and closer. Eventually it will resolve in focus. It will be quite close.

I’ll try it tomorrow weather’s supposed to clear up…

JJ

[Apet-Sure]

Most macro lenses are capable of focusing all the way out to infinity and on anything closer, down to the lens's minimum focus distance. Does your lens have a focus limiter switch/setting/knob? My Pentax-F 100mm Macro does, which tells the lens not to use the full focus range. That could be why autofocus is only using 1/3 of the lens's range. How do you have the camera set up for number of autofocus points? Some cameras have settings for 1 point (spot focus), 5 points (small region focus), or 11 or more points. If the camera is not set to 1 point, then it will decide what it thinks needs to be in focus. That may or may not agree with what you think. Of course, you can always set the camera to manual focus, and turn the focus ring on the lens to get what you want.

[AstroDave]

I’ll try it tomorrow weather’s supposed to clear up…

I suggest doing this indoors (make sure you have lots of light) - your subjects can be stationary - i.e. stamps, coins - rather than bugs or flowers in the wind. You want to wind the lens as far out as you can - in fact, do as as SteveBrot suggests above.

[jerryleejr]

Most macro lenses are capable of focusing all the way out to infinity and on anything closer, down to the lens's minimum focus distance. Does your lens have a focus limiter switch/setting/knob? My Pentax-F 100mm Macro does, which tells the lens not to use the full focus range. That could be why autofocus is only using 1/3 of the lens's range. How do you have the camera set up for number of autofocus points? Some cameras have settings for 1 point (spot focus), 5 points (small region focus), or 11 or more points. If the camera is not set to 1 point, then it will decide what it thinks needs to be in focus. That may or may not agree with what you think. Of course, you can always set the camera to manual focus, and turn the focus ring on the lens to get what you want.

Good info I’ll dig into it tomorrow…

JJ

[swanlefitte]

My 70mm macro doesn't really extend until 1:5 or when you focus on your hand and your fingers fill the frame up top to bottom.
At 1:2 about when 2 fingers fill the frame it extends 3/4 and when just the width of 1 finger takes up the frame top to bottom it extends full.

[aslyfox]

which 100mm macro is being used by the OP ?

not all 100mm macros are capable of 1:1, are they?

the Pentax 100mm f2.8 macro " family ", the F, FA, and the two D FA lenses, is but there are other lenses called " macro " that cannot do 1:1

[jerryleejr]

which 100mm macro is being used by the OP ?

not all 100mm macros are capable of 1:1, are they?

the Pentax 100mm f2.8 macro " family ", the F, FA, and the two D FA lenses, is but there are other lenses called " macro " that cannot do 1:1

It’s the newer one that’s 1:1

JJ

[Rondec]

As others have said, it just depends on where you are focusing. You have to get pretty close to something with the DFA 100 macro to get it to use that part of the focus range. Most of the focus throw of that lens is devoted to focusing close. Infinity focus is a very small portion of it.

[aslyfox]

It’s the newer one that’s 1:1

JJ

this one then

SMC Pentax-D FA 100mm F2.8 Macro WR ?