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07-23-2009, 06:39 AM   #1
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The mandatory fast lens , choices, opinions

It seems most users here agree that for low light photography, a fast lens such as the FA 50 f1,4 is mandatory. I agree. I have used a SMC-M 50 f2 and found it excellent but not quite fat enough. I then got a SMC-A 50 f1,4, found it amazing, but never dared to use it at f1,4, because of the much lower contrast and sharpness at this aperture. I now have an SMC-F 50 f1,7, and feel confortable using it wide open.

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?

07-23-2009, 06:42 AM   #2
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The FA35/2, if you can find one, is very sharp right from f/2. It also gives you a "normal" FOV (i.e. like a 50mm was on a 35mm film camera).
07-23-2009, 06:56 AM   #3
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The F/FA 50 1.7 is very sharp at 1.7--sharper, by most accounts, than the 1.4, but the bokeh is different. Word is, they sacrificed a little sharpness for better bokeh on the 1.4 optical formula.

Some say the 50 f/2 is really the same optically as the 1.7 but it's just restricted to f/2. There was a thread here a few weeks ago about that.

The FA 43 1.9 is a spectacular lens, but of course not much faster than the f/2 you already have. Some say it's soft wide open, but when properly focused it does a great job even at f/1.9. I sold my FA 50 1.7 mostly because of this lens.
07-23-2009, 07:06 AM   #4
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I think it comes to the price to accessibility cross points. the FA50 is still readily available and even at the higher price of $250USD is still relatively cheap compared to the other new AF options out there. The FA35/2 is a stunning performer from all those who report having thelens but right now they are getting harder to come by and you will not find one for less than $300. The same goes for the FA Limiteds. Phenomenal lenses the lot of them but again you pay for the performance. The FA50 1.4 you get a trade off between the speed and softness wide-open. But stop down the lens and you get as sharp an image from the lens as any other in the right conditions.

Personally I lucked out getting my FA50 1.4. I bought a Sigma 50 2.8 Macro locally and then traded it straight up for the FA50 (thanks wallyb!). Well worth the trade in my opinion.

07-23-2009, 08:27 AM   #5
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I have had most of the 50mm lenses in K-mount over time (except the 50/2 versions, as these are too slow for my liking). The FA 50/1,4 is certainly one of the best of the bunch and very useable wide open. There might be a lack of contrast at its widest setting - so what? You need to take into account the prupose of the fast aperture, you either need it for an extremely shallow DOF, (and I really think, that many complaints about poor contrast can be traced back to not correctly focused images at such a shallow DOF) or because the light is extremely poor. In that condition, lack of contrast is simply a none-issue, as a slower lens wouldn't get you the shot.

So my personal conclusion is, that the FA 50/1,4 is not a perfect, but a highly recommended lens.

Also the FA 35/2 is fantastic, very, very sharp and useable fully open. Taking the shorter focal length into account, (which goes hand in hand with longer handholdable exposure times), it is nearly as fast as the 50/1,4. The FA 35/2 beats my 31mm limited in terms of raw sharpness and is so much smaller, as an added bonus.

I would buy both now, as long as you still can get them...

Ben
07-23-2009, 09:11 AM   #6
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QuoteOriginally posted by RBellavance Quote
The FA35/2, if you can find one, is very sharp right from f/2. It also gives you a "normal" FOV (i.e. like a 50mm was on a 35mm film camera).
I agree. I had a S-M-C Takumar 35mm f2 and a Pentax-M 35mm f2, and neither lens was great at f2. I tried the Pentax-M 35mm f2.8 and it was similar except slower. I sold those and bought the FA35/2. I never did a formal test, but I now like my photos taken at wide apertures, and I didn't before.

The FA 28mm f2.8 sounds like the designers took a similar approach, using an aspherical element instead of two or three conventional elements in previous versions. I've read similar comments about its higher contrast and sharpness compared to previous versions, including similar complaints about harshness. I've never tried one. I think its ordinary speed meant no one really missed it when it was discontinued, while the FA35/2 is suddenly "hot".

QuoteOriginally posted by farfisa Quote
Some say the 50 f/2 is really the same optically as the 1.7 but it's just restricted to f/2. There was a thread here a few weeks ago about that.
The Pentax-M 50mm f2.0 only has 5 elements, vs. 6 or 7 in the faster 50s.
07-23-2009, 09:24 AM   #7
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whoever thinks the FA50 is bad at 1.4 is wrong.

07-23-2009, 10:30 AM   #8
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QuoteOriginally posted by Gooshin Quote
whoever thinks the FA50 is bad at 1.4 is wrong.
+1 to that...
07-23-2009, 10:37 AM   #9
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QuoteOriginally posted by bdery Quote
It seems most users here agree that for low light photography, a fast lens such as the FA 50 f1,4 is mandatory. I agree.
Really? I have the FA35/2, and while I use it quite a lot for low light photography, it is plain impossible for me to use it on low f-numbers. At f2 in low light, autofocus is not working at all, and my eyes (and technique) are not good enough to focus manually either in low light.

I usually go with f5.6 or smaller, which at least enables me to get usable pictures.

Here is an example (aurora australis) from yesterday where I was tempted to use f4. It is not very clear. Had I gone to f2, I would not have a usable picture at all. The temperature was -33C so lots of trial and errors was out of the question. It is even more difficult inside because focusing at near objects reduces depth of field even more.

BTW, I am not very experienced so hopefully I will improve my focusing skills.

07-23-2009, 11:18 AM   #10
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This is just a suggestion, I'd say that at that distance flip to manual focus with that lens and focus on infinity. At f4 it should be in focus and even at f2 it should be pretty sharp.

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07-23-2009, 11:31 AM   #11
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For those of you who own a FA 50 f1.7, how sharp are the pictures, when stopped up, for general purpose photography, such as street action, group shots, running children/pets, action shots, etc? I am torn between the Da 40 and the FA 50, but would like a sharp lens for street photography, travel, etc. What do you all suggest? I already have the DA21 for indoors, but it's too wide for outdoor people shots.
07-23-2009, 01:04 PM   #12
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QuoteOriginally posted by djupdal Quote
Really? I have the FA35/2, and while I use it quite a lot for low light photography, it is plain impossible for me to use it on low f-numbers. At f2 in low light, autofocus is not working at all, and my eyes (and technique) are not good enough to focus manually either in low light.

I usually go with f5.6 or smaller, which at least enables me to get usable pictures.

Here is an example (aurora australis) from yesterday where I was tempted to use f4. It is not very clear. Had I gone to f2, I would not have a usable picture at all. The temperature was -33C so lots of trial and errors was out of the question. It is even more difficult inside because focusing at near objects reduces depth of field even more.

BTW, I am not very experienced so hopefully I will improve my focusing skills.

do some correct practice is my suggestion ! this is the first time that I saw an FA 35 f/2 owner complained about sharpness at f/2. very very unusual.

Last edited by Pentaxor; 07-23-2009 at 01:37 PM.
07-23-2009, 01:19 PM   #13
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QuoteOriginally posted by Earlybird Quote
For those of you who own a FA 50 f1.7, how sharp are the pictures, when stopped up, for general purpose photography, such as street action, group shots, running children/pets, action shots, etc? I am torn between the Da 40 and the FA 50, but would like a sharp lens for street photography, travel, etc. What do you all suggest? I already have the DA21 for indoors, but it's too wide for outdoor people shots.
I have the FA 50 1.7 and it is very sharp at 1.7. but I would prefer the FA 35 f/2 over it due to it's FOV equivalent which is ideal for street photography. and personally speaking, considering how sharp the 1.7 is at 1.7 already, the FA 35 just kills it at f2.8 up til f5.6 and a tiny lil bit sharper at f/8 in a few photos (but for most photos in general, they are equally sharp here). it is just too razor sharp IMO. I feel bad for my FA 50 1.7.

Last edited by Pentaxor; 07-23-2009 at 01:26 PM.
07-23-2009, 01:21 PM   #14
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QuoteOriginally posted by Pentaxor Quote
do some correct practice is my suggestion ! this is the first time that I saw an FA 35 f/2 complained about sharpness at f/2. very very unusual.
Sorry, I did not mean to say the FA35/2 is not sharp. My point was that you need skills to use f2 in low light properly, which I clearly do not have. I get much better results at smaller apertures. I therefore reacted to the statement that fast lenses are mandatory in low light. Not so for me.
07-23-2009, 01:45 PM   #15
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QuoteOriginally posted by djupdal Quote
Sorry, I did not mean to say the FA35/2 is not sharp. My point was that you need skills to use f2 in low light properly, which I clearly do not have. I get much better results at smaller apertures. I therefore reacted to the statement that fast lenses are mandatory in low light. Not so for me.
Apart from envying you for your location I would suggest, that you either use a magnifying eyecup, which makes focusing really easier or even jump onto a split screen in exchange for the standard matte screen in your camera. With that, focusing should be much easier. AF is of no use in really dim conditions, like your Aurora. But I agree, that it is very hard to focus correctly under such circumstances, as the Aurora has no well-defined edges but is like a moving veil, which is very hard to focus on (I did that in Iceland, many years ago). You could simply use the FA 35/2's infinity stop, which is not far off from real infinity (if at all) and pre-set your focus that way.

Ben
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