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07-24-2009, 11:53 AM   #31
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QuoteOriginally posted by jhonny0099 Quote
...Is this just a problem with this lens? It's also weird that the focus ring turns REALLY FAR, almost 3 hand twists, but it seems like only about 20% of that range is focusable to me. Does the difference in digital sensor size to film have something to do with its focus? I also find that at infinity, I'd like to go a little further to focus, but the focus ring is already maxed out. And sometimes in my blurry shots, I find that other areas in my shot are very crisp, but not the subject under my center focus point. Any ideas?

But I have found a trick that works most of the time...
That's focus trap. If focus trapping works, and you have other photos with in-focus areas, just not exactly where you intended them to be, you are at least part of the problem. It may not be easy, but it should be possible. Try to get your intended point of perfect focus in the middle of the range that looks focused in the viewfinder, not just looking sharp but on the edge of being out of focus.

Your lens might also need some work. It should definitely focus to infinity. I don't know how far the focus ring turns from 0.45m to infinity, but it should be less than a full turn, probably something like 180º to 225º. You might have some loose screws. With a jeweler's phillips screwdriver and something to get the "name" ring off you can fix the infinity problem yourself.

07-24-2009, 12:24 PM   #32
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QuoteOriginally posted by Ben_Edict Quote
Pål, whatever you write is ofcourse correct. But in real world imaging, the rules need not be that strict. The hyperfocal distance for a 35mm lens at f/2 is just above 32m (on a K20), so simply turning the lens to its infinity stop, should be well within the DOF, even taking varying temperatures into account. With longer lenses, focusing is a harder act and one needs to invest more time and brains to get the best result - as you wrote.

Ben
My experience was not with the FA 35/2, a lens I've never used, but generally faster lenses (and a couple of slower ones; A 24/2.8 and A 35/2.8): the three FA Limiteds mainly. The Limiteds are designed to focus ever so little past infinity (to compensate for thermal expansion) so cranking them to they stop at the infinity mark won't necessarily give you optimum performance.
I also noticed that the precise infinity point on the lenses varied with temperature and camera bodies. I tried the camera in room temperature (kept indoors) and at minus 5 degree C. The LX was more prone to thermal variations than the MZ-S.
I found this a real hassle and almost alwas just stopped the lenses to F:4 for razor sharp images.....
Never tried aurora with digital but think I will the coming winter....
07-24-2009, 12:42 PM   #33
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As for the original question (the FA 50/1.4), it is a very good lens with excellent price/performance ratio. It feels a bit "plasticky", but the performace is excellent. It is definitely not "poor", just "less stellar". There is a review at dpreview that nicely sums it up.

Pentax SMC FA 50mm F1.4 Lens Review: 5. Conclusion & samples: Digital Photography Review

QuoteQuote:
So in summary, this is a lens that you buy for its stellar performance when stopped down a bit, and for the fact that it can be opened up to F1.4 when necessary rather than the imagery it creates when it gets there. This makes it an excellent complement to zooms, offering additional capabilities for when light levels drop or shallow depth of field is desired. It may no longer quite be state-of-the-art as far as fast primes are concerned, but still it offers a lot of value for a relatively low price.
You have to really watch where to focus and how to compose shots when the lens is at 1.4, there is no margin for error. I think a lot of complaints about softness are because people forget just how shallow the DOF is.

07-24-2009, 02:32 PM   #34
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Interesting thread. I have an old M 50mm 1.4 and it is the fastest lens I own. For some reason I seldom seem to use it so that extra speed rarely put to the test. Like many others I have found the lens to be soft wide open. On the other hand it is the only lens I have for shooting in available murk. I find I seldom reach for this lens however. I find for the type of shooting I do most I need a faster telephoto lens. So for my purposes the mandatory fast lens is not a 50mm but rather my K 200/2.5. Not f 1.4 but pretty fast for a telephoto. It is very bright in the viewfinder and easy to focus as a result. I like the added reach and find it works well in school gyms and dimly lit auditoriums. As bdery stated above “not all people will agree but a fast telephoto is my choice.


Last edited by 8540tomg; 07-24-2009 at 07:59 PM. Reason: typo
07-24-2009, 02:50 PM   #35
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I have a few 50mm 1.4s, but as I rarely shoot wide open with this focal length, I usually shoot with one of my 55 1.8s, as I prefer these ( When I do shoot wide open in low light situations, I find the 1.8s to be slightly sharper anyway, & I'm willing to sacrifice the extra bit of speed for this extra bit of clarity). The only other lens I own which matches these in speed is my 85mm 1.8, which I do sometimes shoot wide open with, for portraiture DOF.

Last edited by raymeedc; 07-25-2009 at 05:56 AM.
07-25-2009, 04:18 AM   #36
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i have two 50mm f1.2 and one 50mm FA f1.4 plus one takumar 55mm f1.8.
Of these i mostly use 50mm f1.2 mostly in low light situtations and i am very happy with it.

If light is good enough i prefer 55mm f1.8 because i think it is sharpest lense wide open.

Between 50mm f1.2 and 50mm f1.4, i do not even know when was the last time i used FA version. I might probably end up giving it to my brother to play with it.


I can not explain but why but there is some differences in pictures among them, i least liked pictures of FA version.

Further, i really do not buy the argument that one should be happy buying a fast prime know that stopping down at f4 or f8 you will get sharp pictures. I do not know about others but i pay money for fast lenses so that i can use them as fast as possible.
07-25-2009, 04:52 AM   #37
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Big aperture is useful

QuoteOriginally posted by bdery Quote
Most people say the FA 50 f1,4 also lacks contrast and sharpness wide open. So my question is : does it make sense to get a wider lens if the widest setting is so "poor" (all things being relative). Would a, f1,7, or even an f1,9 lens like the 43 mm, make more sense? to me it does, but not all people agree.

What are your opinions?
A big aperture is still useful for achieving more precise focus even if not useful for the actual exposure. So while an A50/1.7 may take good shots at 1.7, it would still be nice if the aperture went even larger so as to really nail the focus.
07-25-2009, 05:24 AM   #38
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QuoteQuote:
Further, i really do not buy the argument that one should be happy buying a fast prime know that stopping down at f4 or f8 you will get sharp pictures. I do not know about others but i pay money for fast lenses so that i can use them as fast as possible.
My point exactly. I personnally often use my fast fifty focused at infinity, for cityscapes and similar scenes. I also carry it with me when I go take a stroll and think I might take pictures, it has the added advantage of being very light.

I'm surprised that not many people vouch for the 43 f1,9, it would seem an interesting option for that purpose.

07-25-2009, 12:06 PM   #39
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QuoteOriginally posted by bdery Quote
My point exactly. I personnally often use my fast fifty focused at infinity, for cityscapes and similar scenes. I also carry it with me when I go take a stroll and think I might take pictures, it has the added advantage of being very light.

I'm surprised that not many people vouch for the 43 f1,9, it would seem an interesting option for that purpose.
the current price of the 43 f1.9, doesn't make it a logical choice. if they were cheaper, well why not?

Last edited by Pentaxor; 07-25-2009 at 04:53 PM.
07-25-2009, 03:03 PM   #40
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QuoteOriginally posted by bdery Quote
My point exactly. I personnally often use my fast fifty focused at infinity, for cityscapes and similar scenes. I also carry it with me when I go take a stroll and think I might take pictures, it has the added advantage of being very light.
Exactly. Here is an example 50mm at f1.2. Boat is moving, so shutter has to be fast enough.
(this is handheld)




QuoteOriginally posted by bdery Quote
I'm surprised that not many people vouch for the 43 f1,9, it would seem an interesting option for that purpose.
At least i thought about this lense many times, but have no money for it. But this is front runner for me.
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