Focus frustration with fast glass

[SciAggie]

I am beginning to see why some people report a love/ hate relationship with really fast lenses. I am gaining some experience with the f/1 Noctilux and the Canon f/0.95. These lenses can be frustrating in some situations. I'm curious about the success people have focusing these lenses in practical use. I'm not refering to front/ back focus issues. I seem to only nail the focus about 20% of the time. It's not always about missed focus - sometimes I just choose the wrong place to place the thin DOF.

What is your story? Here is a shot that worked out:

This one is close, but not quite right:

 

[back alley]

is that a havanese?

 

[SciAggie]

I had to look up Havanese.. No, it is a Yorkypoo. That's a fancy name for a mutt cross between a Yorkshire Terrier and a Miniature Poodle. He's a sweet little dog.

 

[gavinlg]

Use a smaller aperture, or alternatively use an SLR (more accurate). Hehe...

 

[maddoc]

Use a smaller aperture, or alternatively use an SLR (more accurate). Hehe...

I have yet to see a SLR with more accurate focus ... 😀

 

[Brian Legge]

Honestly, the focus in the second shoot look about right.

What strikes you as not quite right? Its hard to tell if the focus is on given the dark dog, shadows in the eyes and uncertainty about where you ware trying to nail focus.

 

[bwcolor]

My lenses are not quite that fast f/1.2 and a couple of f/1.4's. All are 50mm.


First, I'm not so sure that you can ignore front and back focusing. I sent my f/1.2 off to adjust focus at a particular distance.

Second, I shoot with M3's or other rangefinders with viewfinder magnification.

Third, I have had many out of focus shots that were actually camera shake, or subject motion.

Lastly, I am never surprised when I miss the exact focusing that I was after, especially when photographing live subjects.

 

[LKeithR]

I have been playing with a couple (relatively) fast lenses on my "clunky" DSLR of late without too much success. I have a Revuenon 55/1.2 which is, admittedly, not as fast as a .95 or 1.1 but still can be a bear to focus. While I'm a big fan of the OOf effects of using fast lenses I'm not sure if anything faster than 1.4 is necessary for most shots. An image shot at f1.4 can still have some very nice rendering but it's "much" easier to focus an 1.4 than a 1.2...

 

[gavinlg]

I have been playing with a couple (relatively) fast lenses on my "clunky" DSLR of late without too much success. I have a Revuenon 55/1.2 which is, admittedly, not as fast as a .95 or 1.1 but still can be a bear to focus. While I'm a big fan of the OOf effects of using fast lenses I'm not sure if anything faster than 1.4 is necessary for most shots. An image shot at f1.4 can still have some very nice rendering but it's "much" easier to focus an 1.4 than a 1.2...

DSLRs aren't really set up for MF. Focusing on something like an OM1 with the split screen and microprism is extremely accurate in comparison...

 

[whitecat]

This is why I sold my Noctilux.

 

[maddoc]

Actually, I have never understood what the point is to get pin-point focus with a f/1.0 or f/1.2 lens in short distances. 😕 For me the Noctilux works best somewhere between 3m and 5m focus distance and with subjects where the exact plane of focus has not to be 100% perfect.

 

[igi]

With so little DOF at wide-open, only the nose of the dog might be in focus😀

Plus, ultra fast lenses tend to be soft wide-open... yes there are a whole lot of problems with wide-open shooting...

 

[retnull]

I use an Angenieux 25/0.95 c-mount lens on my Panasonic micro4/3ds camera. The wider aperatures are just too difficult for me, I decided there's not much point in going below f2.

Maybe the advantage of a super-fast lens is that by f2, it is already stopped down a bit, and should be performing better than a lens whose widest aperture is f2.

If bokeh is the ultimate goal, I'd say: 1) use the longest possible lens, 2) use a tripod, and 3) take your time focusing.

It's a tough job using a lens like the Noctilux for happy snaps.

 

[Renzsu]

Not sure what the problem is, I have no problems focusing where I want, it's the front/back focusing that causes issues for me. Sometimes you need to correct for it quite drastically (on my M8 btw, it's less of an issue on film).

 

[rxmd]

Maybe the advantage of a super-fast lens is that by f2, it is already stopped down a bit, and should be performing better than a lens whose widest aperture is f2.

In sort: no.

The reason to choose an f/1 lens over a f/2 lens is using it at f/1 and f/1.4. To make a fast lens, you have to take a lot of design compromises. Slower lenses tend to be better because you have to jump through less hoops to make it fast and can instead take care of other issues.

 

[Roger Hicks]

In short: no.

The reason to choose an f/1 lens over a f/2 lens is using it at f/1 and f/1.4. To make a fast lens, you have to take a lot of design compromises. Slower lenses tend to be better because you have to jump through less hoops to make it fast and can instead take care of other issues.

Exactly.

As for other arguments, much as I love the Noctilux, I ddn't make the necessary sacrifices to buy it because d-o-f is so tiny and the lens is so big. For me, my f/1.5 Sonnar and 35 Summilux are fast enough, with adequate d-o-f, even though I use both at full aperture on a regular basis.

Among other fast lenses, again for me the 75 Summicron is vastly more convenient than the huge, heavy, zero d-o-f 75 Summilux. I sold my 50/1.2 Nikkor because I hardy ever used it, and I gave away my 50/1.2 Canon because of miserable image quality at f/1.2 (and no, I didn't have a bad one, I just don't think they're any good wide open).

Then again, I'm with Gabor on normal working distances. 'Extreme bokeh' shots (sharp image a metre away, everything else out of focus) sometimes make me feel literally physically sick.

Cheers,

R.

 

[oftheherd]

Use a smaller aperture, or alternatively use an SLR (more accurate). Hehe...

There is no doubt that the SLR screen, giving a good approximation of what you are going to get, will aid in getting the photo. I like SLR with f/1.4 in very low light. But then none of my SLR have f/.95 or even f/1 lenses, so I can't comment of using them with SLR (not with RF either).

 

[Juan Valdenebro]

Yes, fast lenses are problematic for close focusing...

And we don't have to go to f/0,95 to see it! To me 1.4 is hard for close focusing (SLRs and RFs) and it's my speed limit... Even more: if I remember well, when I tested my Summicron 90 at f/2 with tripod, its DOF was 2 or 3 millimeters! Can be used for effects portraiture, though...

In general I try to use those f-stops focusing far from camera: 2 meters and beyond, and in those cases I never shoot unless I can use a fast shutter speed above 1/60 in general, and with the 90 at least 1/125... I prefer to get the speed and underexpose in any case... And at those wide f-stops, for close focusing we get nice OOF anyway if we close aperture a bit... I don't see much sense in lenses faster than f/1.4 for real life shooting, but as everything in photography, it depends: if you shoot with lots of time in front of your subject, or with lots of light or tripod, I guess they make sense... In my case I've never wanted a lens faster than f/1.4... I seldom use mine wider than f/2...

Cheers,

Juan

 

[Livesteamer]

You need a .85 finder or the M3. When I use the Noctilux on one of my M6 .72 finders the results are not great. Now I only use f1.0 with my M6 .85. Sherry K. upgraded my M6 .85 finder two years ago and it works well with the Noctilux. Roger is right that the Noctilux is a specialty lens and I find I only take it out when I really need that extra stop. Joe

 

[ferider]

1) just because the glass is big, it doesn't mean the DOF is very thin, comparatively. A 90/2 wide open has much thinner DOF than a 50/1, and people use it all the time.
2) the classic fast lenses out there (like the Noctilux) were made for wide open, journalistic type (10m and beyond) photography. Not for close up portraits and bokeh shots. It is questionable how good a portrait is when one eye is in focus and the other isn't. Just food for thought.
3) change technique: pre-focus the lens, and move your body.
4) focus bracket if your subject allows.
5) use a camera with long EBL and little back-lash; do some test shots to make sure your camera and lens are well adjusted to each other.

And as an example, one of our members (Randy) taken with 75/1.4. On a normal M6 classic as he can witness (for DOF numbers, check dofmaster.com). Re-composing after focusing is an additional challenge 🙂

Roland.