[truonganh]

I want to start a thread dedicated to this workhorse. This humble lens is inexpensive, fast, very high quality for the money, and just about everyone I know that own a pentax probably have one (mostly FA version). Okay, it's not a Limited, but the plastic housing and the mechanical never fail on me yet.

Ok so here is the basic downside: it's rather soft at wide open. Even at 2.0, i think it's still a bit soft... Heck, my M-50 f1.7 is sharper wide open than the FA1.4 at 2.0

So here are the discussion topics:

- How do you guys take advantage of this inherent softness? (please show some example if you have some)

- are there other PP tricks to overcome the softness? As an example, I have resized some photos and then apply sharpening to it. With the current 10M & 14M camera, these are every much not a problem.
- How much resizing would be optimal to create a visually sharp (wide-open shot) w/o making the photo too small to be useful?...

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Last edited by truonganh; 07-30-2008 at 12:43 PM.

[creampuff]

First off, I've owned 2 of the FA 50mm f/1.4, and tested no less that 6 copies of it in the shop on my last purchase and they all show ever so slight variations. So if you say your copy is soft, then I would reckon you probably didn't get a good copy. Mine were pretty sharp wide open by my estimation.

No amount of PP can sharpen a soft image because sharpening basically looks for edge variations. It won't be able to radically improve an image that is inherently soft to begin with. Perhaps use of the find edges and high pass filters plus clever use of USM or smart sharpen can help a bit.

[truonganh]

That is an interesting observation. I do only have 1 copy so can't say that my copy is worse or better.

That said, I can say with confidence that when i used it at f2.0 and up, it is already incredibly sharp. This observation appears consistent with other owners....

Here's some unedited comparison
First group is the FA50f1.4 wide open, followed by 100% crop.. 2nd pic is the A50f1.7 wide open, followed at 100% crop

[truonganh]

ok so for 1 to 1 comparison, 3rd pic is FA50f1.4 at 1.7, followed by 100% crop.
Next is when the the 50f1.4 shows its true brilliance, stop down to 2.0, and then 2.8

Attached Images

 

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Last edited by truonganh; 11-06-2012 at 09:45 PM.

[truonganh]

...and one more step down to 4.0, and this workhorse shows its true color with bleeding sharpness...

[sewebster]

I took some test shots of a textured concrete surface and was able to see a huge difference in my copy from 1.4 to 2.8. To be specific, 1.4 and 2.0 were pretty similar, then 2.8 was much better (I could post these if desired).

However, in practice, I find 1.4 to be fine. I posted a few pics in this thread:
https://www.pentaxforums.com/forums/post-your-photos/32741-more-cat-taken-new-fa50-1-4-a.html
Compare the 2nd and 3rd shots, first 1.4, then 2.8. Both look pretty good to me.

I often choose 2.8 just to get more depth of field. With a reasonable ISO and shake reduction I can still handhold without flash indoors. 1.4 is nice for DOF effects and quick snaps without worrying about slow shutter speed blurring.

[felix68]

I have found that some of the softness can be adjusted with the "RL Deconvolution" function in Raw Therapee. I think that Photoshop has this function as well.
My copy of this lens is pretty darn sharp at f2.0 and up. I have posted this pic before but it is a good example of a shot af f2 with some unsharp mask applied.

[frank]

I have found that some of the softness can be adjusted with the "RL Deconvolution" function in Raw Therapee. I think that Photoshop has this function as well.
My copy of this lens is pretty darn sharp at f2.0 and up. I have posted this pic before but it is a good example of a shot af f2 with some unsharp mask applied.

Beautiful! Both the photo and the girl.

[jsherman999]

The FA 50 1.4 is a great lens..... inspirational thread. I guess I'll have to put it back on the camera for a while!

I think my copy of the FA50 1.4 is usually a bit of a softy till F2.8, then razor like.
But more often than not it seems the AF may be more of the problem at 1.4 or 2.0 for me than the lens being soft.

I have found that I can sometimes get sharper results with MF than with the AF, in light where I might be using F1.4-F2. These are just my observations.

But sometimes it just blows me away... That is what is so frustrating about this lens.

Here is one of my first shots with it. In a dark front lobby at work the day/night I got the lens, and I made my friend pose while I snapped shots. Most were a tad soft but then I would get one like this and....

This is a crop of the original...


And a 100% crop


Model = PENTAX K100D
Exposure Time = 1/30"
F Number = F1.4
Exposure Program = Aperture priority
ISO Speed Ratings = 800
Exposure Bias Value = ±0EV
Flash = Flash did not fire, compulsory flash mode
Focal Length = 50mm


I mean its not glass cutting sharp but for F1.4 in some funky lighting, handheld and ISO 800... If it did this all the time I would never complain about it...

It is truly a LOVE/LIKE relationship... I never hate it, but it does frustrate the jeepers out me sometimes

[sewebster]

Yeah, for me the focusing is a bit tricky at 1.4 especially on autofocus in dim light indoors... the camera can be fairly annoying actually. It is in focus (close enough for me to want to take the picture) but I can't! The camera won't let me. I reprogrammed the "ok" button in the custom settings to "cancel AF" and that lets me take the shot, but too bad you can't just inactivate the thing that doesn't let you take the photo without AF lock. I mean, if I push the button, take the picture, always. (Am I just missing something here? Sorry to threadjack).

[Mechan1k]

Mine is a keeper:

I stop mine down a little bit knowing that f/1.4 is going to be a fraction soft ... so that doesn't bother me.

These were taken have a number of beers ... hand held with my right hand (beer in left hand).

[benplaut]

I've found that the majority of softness problems at f1.4/f2 are caused by my own shakyness moving around the razor thin DoF. YMMV, but try a few shots on a tripod to determine if you are the cause.

Anyway, I love this lens...

[Ash]

Yep, the challenge in getting what you want in focus at these large apertures.
You might struggle to find what level in the picture is in focus at f/1.4-f/2

[sinus007]

Hi,
I'm a newbie to pentax but I'm so happy that, after reading a lot about this lens, I went over budget and bought it.
I didn't do any kind of testing but it seems to me that when I use it with F2 and below I'm getting better results in MF than AF (I have k200d).