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11-24-2011, 05:23 AM   #16
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+1 : Live View (+ magnification) is a great way to get the focus spot on with MF lenses. Of course not much use if one wants to use the OVF and/or there is no time to hone the focus in, but e.g. with macro shots from a tripod it is the perfect thing to have. (It is perhaps worth noting that the AF fine adustment does not affect this in any way, nor does it affect CDAF, that is, AF while LiveView is active; the fine adjustment is essentially a bias applied to the dedicated AF sensor living under the mirror).

11-24-2011, 07:28 AM   #17
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QuoteOriginally posted by pentup Quote
You'd only want them in one group if they each needed exactly the same adjustment; I think someone already pointed out that the adjustment would only affect at what point the green hexagon showed up, to aid you in manual focusing. Personally I wouldn't bother. I ignore the hexagon and try my best to rely on my eyes. Even if all BF/FF is eliminated, the AF could still simply disagree with you about what the exact target should be.



Stop down, for one thing -- the DOF will be a sliver wide open at that length. And you should search for the several threads about focusing screens; there's a lot of information on here about modifying your camera to improve manual focusing.
Thanks, pentup.

I am now getting to the point with all this, finally.

As far as stopping down the 85/1.4, I know it would become more precise in manually focusing this lens but of course I had bought this lens because of its wide aperture! Nice Bokeh when you can get it to "work" at f1.4.

About focusing screens, indeed this is something I should now consider ... I've read a thread regarding the "best" ones out there :
https://www.pentaxforums.com/forums/pentax-dslr-discussion/165613-great-focus...evelation.html
but, as always, I am leary of fiddling with this.

JP
11-24-2011, 07:39 AM   #18
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Another focusing screen thread: https://www.pentaxforums.com/forums/pentax-k-5-forum/142241-best-screen-ever-...anon-ee-s.html.
11-24-2011, 07:40 AM   #19
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Replying to the comments below in "blue" type:

QuoteOriginally posted by jatrax Quote
I think this may have strayed a bit mostly because the OP mentioned FF/BF which has a specific meaning to many people. It appears the OP is looking for advice on how to get better focusing results and really does not have a FF/BF issue.

1) When FF/BF is mentioned this almost always is because a particular lens does not auto-focus precisely on a particular camera. The K-5 and other higher end cameras provide the means to tune the auto-focus for each lens to be more precise. Other camera's (k-x & k-r) have an adjustment but it is all or nothing.

You may have hit the nail right on!
Perhaps (most likely) it is more about getting proper focus, and subsequent results, that I am looking for.
My thread title should have perhaps been edited with the inclusion of "achieving focus".


2) There are four ways to manually focus on Pentax DSLR's. First is using the viewfinder and the focusing screen. This was perhaps more accurate on older full frame film cameras because the view finder was optimized for manual focus. Modern DSLRs have view finders optimized for auto-focus lenses which may not be good enough with a very fast lens like the 85 f/1.4, where the depth of field wide open is extremely small. The second is use the green hexagon to indicate that something is in focus. I find this works fine if the depth of field is large (lens stopped down) but not accurate enough with a fast lens. The third is to use catch in focus (CIF) which uses the auto-focus sensor to trip the shutter when a focus lock is obtained while using a manual focus lens. Some report this works very well, but I have not used it that much.

I have used it once and that was for testing purposes when I got my K5. Never used it since but it is a good idea to revisit the feature. Maybe that'll help.

Fourth is to use the live view either as is or by zooming in. This has the advantage of not using either the auto-focus sensor or the focusing screen. I find it works very well if the camera is on a tripod and I have the time, but it is too slow for many shots.

Definitely on my agenda for the weekend: test focus (at f1.4) using the Live View feature.
Of course, this is not something I can use all the time depending, on the situations.


3) There are a few things that can be done to help with manual focusing. I have changed out the focusing screen for one better suited to manual focus lenses. Search for katz-eye or focusingscreen.com. I have also added a Pentax O-ME53 magnifying eye piece which zooms in a bit although you lose some view of the indicator lights in the camera. With these changes I find my accuracy with manual focus has improved a good bit.

Yes, again the focusing screen bit is coming back to haunt me! As I mentioned earlier, this is something I am very leary about, especially if it involves "shimming".

4) No matter which method you use for manual focusing, a good bit of practice is involved. Remember the view finder is not as good as they used to be so you have to be better. There are some manual focusing exercises out there, do a search for 'manual focusing tips'. But for me the best way is to gradually move the focus back and forth until the image 'pops' in the view finder. It takes lots of practice to start seeing when that happens. Also keep in mind that the 85mm f/1.4 has a depth of field at 8 feet of less than 2 inches. That means you can easily get the nose in focus and the eyes blurry. With a slow lens, like the 18-55 kit lens, 2 inches is close enough. With something like the 85mm f/1.4 is just isn't, you have to be exactly precise.

Thanks for the tips. Obviously, I need more practice with this in spite of all of those years having used SLR's in the past ... seems like it was quite a bit easier to get proper manual focus, even on fast lenses.
Thank you for the reply!

Cheers.

JP

11-24-2011, 07:44 AM   #20
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Posted twice !! Sorry .
11-24-2011, 07:47 AM   #21
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QuoteOriginally posted by lytrytyr Quote
There may be another issue at stake here, depending on the particular 85/1.4 lens: focus shift.
However accurately the lens may be focused at f/1.4, it could move off when stopped down to f/2 or further.
For static shots from a tripod you could try stopping down with the green button and using live view,
but for hand-held shots I suppose you just have to know your lens
and focus accordingly (probably a little bit in front of the subject).

The web page
Zeiss 85mm f/1.4 ZE Planar T* Lens Review
has a good discussion of this.
Great!

And guess what? This is exactly the lens which I have been discussing all along!

I have good results when stopped down from F2.8 and smaller aperturesld have mentioned that the point of my thread is to find ways to get proper manual focus at wider apertures with the said lens.
This BF/FF stuff probably was a wrong statement in the first place!
I should have included that in the title and/or in the opening post.

Thanks a bunch!

JP
11-24-2011, 07:49 AM   #22
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QuoteOriginally posted by jolepp Quote
Thanks Jolepp ... just posted that above.

JP
11-24-2011, 09:12 AM   #23
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QuoteOriginally posted by jpzk Quote
lytrytyr
This was an excellent link, and thanks for posting it.

I've read the entire review TWICE and came to the conclusion that it is NOT BF/FF which I am dealing with but an inherent "feature" of the lens itself, because of its optics.
Nothing actually wrong with the lens, but rather a matter of understanding how it works.

Without this review, I would have been totally discouraged with this lens.

Now to the nitty-gritties ....

While using the lens wide open, the correct focus lies usually a little bit in front of the point that has been expected. Beside this, the focus confirmation function of any AF-camera is a relative improper tool for accurate focusing of an f/1.4 lens on closer distances. Also, a standard focusing screen and viewfinder of an SLR camera shows the limitations of accurate manual focusing with an 85mm lens at f/1.4. For instance, it is not possible in practical use to focus more accurately than about +/- 2 cm at an object distance of 1m without additional magnification systems. For accurate focusing at full aperture or stopped down a little bit, we strongly recommend:
-use a tripod if possible
-use zoom-in function in live-view mode while the lens has been stopped down to the designated f-stop.
-focus bracketing exposures (with small steps of rotating the focusing ring)"


Zeiss mentions the "standard" focusing screens are not the best to use with this lens.
So, I will definitely look into getting a proper screen. Which one? There are at least two out there which are considered among the best:
Katz-Eye and the Canon one discussed in another thread.

" ... without additional magnification systems ..." what is this exactly?

They suggest LiveView and focus bracketing; that's fine with me (I will give it a go today) but that could also be a problem when you want to use the lens wide open and via the viewfinder!

So, it looks like I will be in the market for a focusing screen although I am very leary about the installing and perhaps "shimming" that thing.
If that is what it takes ... I will likely ask for much more help here!

Since I also have a K7, I should do the screen job on that camera rather than on my K5 ... just in case.
I use the K7 most often with the DA*16-50 and other lenses (primes) and pretty much leave the "big lenses" to the K5 (DA*300/4 and Tammy 70-200/2.8).

That seems to have wrapped up my quest for an answer to my original, and erroneously titled, query.

To all of you who have responded ... Big Thanks!!

I will report back here with my "tests"..

JP

11-24-2011, 09:17 AM   #24
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QuoteOriginally posted by jpzk Quote
seems like it was quite a bit easier to get proper manual focus, even on fast lenses.
I'm quite certain it was. My SLR days were years ago, I went digital very early and used P&S's for a number of years before coming back to a DSLR. The thing I noticed immediately is that the view finder is just not nearly as good. I still had my SLR at the time (since sold on) and the comparison is stunning. I have a Spotmatic in the cupboard which I take out occasionally and there is no comparison between the view finders.

I realize that modern photographers are supposed to use AF lenses but I really wish Pentax would put a great view finder in their cameras again. It would differentiate them from the crowd in an area that you notice every time you take a picture.
11-24-2011, 10:07 AM   #25
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QuoteOriginally posted by jpzk Quote
" ... without additional magnification systems ..." what is this exactly?JP

I would think they mean either zooming in live view,
or else an optical eyepiece magnifier of the type jatrax mentioned:

QuoteOriginally posted by jatrax Quote
I have also added a Pentax O-ME53 magnifying eye piece which zooms in a bit although you lose some view of the indicator lights in the camera. With these changes I find my accuracy with manual focus has improved a good bit.

Good luck with the ZeeK 85, JP!

It seems that that lens is like its ZeeK 25 stablemate:
a deep, quirky lens that can be frustrating at first,
but extremely rewarding when you do get the hang of it.
11-24-2011, 10:20 AM   #26
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QuoteOriginally posted by jatrax Quote
My SLR days were years ago, I went digital very early and used P&S's for a number of years before coming back to a DSLR. The thing I noticed immediately is that the view finder is just not nearly as good. I still had my SLR at the time (since sold on) and the comparison is stunning. I have a Spotmatic in the cupboard which I take out occasionally and there is no comparison between the view finders.
Well, FWIW, I moved to the Spotmatic after using an SLR with a split rangefinder screen.
I rarely found it easy to focus with the Spotmatic's microprisms,
trying to get my eye lined up at the right angle to the eyepiece.
YMMV, but I don't think the good old days were that good after all!
11-24-2011, 10:21 AM   #27
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QuoteOriginally posted by jatrax Quote
I'm quite certain it was. My SLR days were years ago, I went digital very early and used P&S's for a number of years before coming back to a DSLR. The thing I noticed immediately is that the view finder is just not nearly as good. I still had my SLR at the time (since sold on) and the comparison is stunning. I have a Spotmatic in the cupboard which I take out occasionally and there is no comparison between the view finders.

I realize that modern photographers are supposed to use AF lenses but I really wish Pentax would put a great view finder in their cameras again. It would differentiate them from the crowd in an area that you notice every time you take a picture.
Well Pentax still makes the A 50 f1.2 and focusing anything that fast needs a good VF and proper screen, so the modern users should be using an AF lens is a poor excuse really, Even though they are AF the macro m=lenses will need fine focus adjust as well manually
11-24-2011, 11:30 AM   #28
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The biggeat problem in manual focus with *any* fast lens is that the actual DOF in the image is going to be shallower - perhaps MUCH shallower - than what it appeara in he viewfinder. Meaning some things that appear in focus in the viewfinder won't be in focus in the actual picture. That isn't BF or FF, it's just life with a focus screen that was optimized for higher brightness at smaller apertures, not for more accurate DOF at larger apertures.

It's easy enough to see the effect for yourself by shooting some text on an angle.- see how many lines appear in focus in the viewfinder, then take the shot and compare. Once youve convinced yourself the effect is real, next step is just to practice, teaching yourself how to focus in such a way that your inended subject is part of the image that is eally in focus, not part of the image that only appears to be in focus in the viewfinder.
11-24-2011, 05:13 PM   #29
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QuoteOriginally posted by jatrax Quote
I realize that modern photographers are supposed to use AF lenses but I really wish Pentax would put a great view finder in their cameras again. It would differentiate them from the crowd in an area that you notice every time you take a picture
That is so true: a great viewfinder would be such a "non-luxury" feature! I mean, what you can see in the VF will most often than not make a huge difference in composition. Better brightness and coverage would be a very welcomed item for me who has a poor left eyesight!
Maybe Pentax will provide us with such "non-luxury" in the near future now that Ricoh is the game player?

JP
11-24-2011, 05:15 PM   #30
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QuoteOriginally posted by lytrytyr Quote
I would think they mean either zooming in live view,
or else an optical eyepiece magnifier of the type jatrax mentioned: Originally posted by jatrax I have also added a Pentax O-ME53 magnifying eye piece which zooms in a bit although you lose some view of the indicator lights in the camera. With these changes I find my accuracy with manual focus has improved a good bit
OK, so that is probably what they meant then, i.e.: zooming in live view.
I was once tempted with a magnifying eyepiece but I read that it often hinders more than it helps people (like me) who wear glasses.

JP
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