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03-05-2012, 04:42 PM   #1
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*HELP* FA 50 f1.4 or DA 70 f2.4 ltd or FA 77 f1.8

hey guys i am supposed to be taking some pictures for my friends its going to be about a group of 3-5 people. i currently have a M 50 1.7 and the 2 kit lenses that came with the Kx.

i was going to rent one of the aforementioned lenses in the title for the week i do the photos and im currently stuck choosing. from what i understand, the image of the 50 and the 70 should be similar in respects to what is going to be framed in the image at the same distances, but the 77 is going to be more zoomed in...due to the fact of the crop factor that makes it look like its a 115.5 lens. i was doing some test shots with my 55-300 to see how far i would need to be to fit about 4 ppl in the frame. it was probably about 40 ft...and much less for the other lenses.

would y'all choose the 'longer' lens over the two shorter ones?

thanks for the help

03-05-2012, 04:53 PM   #2
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For a group shot of 3-5 people even a FA50 is a little long, but of the other options that's the one I'd choose. Just make sure you stop it down plenty to get everyone in focus (like f/8 or more). Which makes me wonder why you don't just use your M50/1.7?
03-05-2012, 05:01 PM   #3
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its somewhat of a 'graduation' picture type thing outside in a park...and i figure my manual lens would be a little hard to focus with accuracy and speed..which is why i was thinking about getting the 50...should i use a little wider lens? only reason i never considered a wider lens was that i read that it would distort the image a little..

other options from the rentals website are the DA 40 ltd and the FA 31 1.8 ltd

should i also stick with a fixed focal length or get one that can zoom...
03-05-2012, 05:01 PM   #4
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Save some money and use the M50 and a tripod.

03-05-2012, 05:09 PM   #5
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QuoteOriginally posted by ninjasaurusrex Quote
its somewhat of a 'graduation' picture type thing outside in a park...and i figure my manual lens would be a little hard to focus with accuracy and speed..which is why i was thinking about getting the 50...should i use a little wider lens? only reason i never considered a wider lens was that i read that it would distort the image a little..

other options from the rentals website are the DA 40 ltd and the FA 31 1.8 ltd

should i also stick with a fixed focal length or get one that can zoom...
Hmmm. If I wanted to take a pic of 3 to 5 people I'd use the FA50 for a tight group shot, and the FA31 for a wider shot. 70mm is just too long unless you want to also do individual portraits (in which case the FA50 could do almost as good of a job).

I can understand your hesitation on using your manual 50 when you feel you absolutely have to nail the shot. Like I said before though, if you go a FA50 you must must stop it down for a group shot, don't get tempted with the f/1.4 writing on the barrel. I can't tell you how many shots of 2 or more people I've stuffed up because I didn't stop down enough.
03-05-2012, 05:21 PM   #6
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ok and about the distortion...i think i read somewhere that distortions are only apparent when the relative distances of the object are closer to the lens..ex taking pictures of two objects that are 2 ft apart from a couple hundred of feet away would make it more 'flat' than say taking it from only 10 ft away. is there any kind of rule of thumb to combat distortion without making the image look flat if i choose the fa31 and want to also do individual portraits..will it be to short?
03-05-2012, 05:29 PM   #7
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Just don't stand too close. It's all to do with distance rather than focal length. Better to stand back a bit and crop latter, (believe me the FA31 is very sharp and can withstand a bit of cropping), than stand under say just 2 meters away and end up with distortions.

For head and shoulder portraits then yeah, the FA31 is possibly too short. For half length, or better full length, it's great. You can try it out yourself though by putting your kit lens on ~31mm and see how you go.
03-05-2012, 05:40 PM   #8
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LOL im very very confused now...

i put my 50 1.7 and took a picture and then my 18-55 and took a picture at ~50 and its the same...so what's this crop factor nonsense..lol

03-05-2012, 05:48 PM   #9
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QuoteOriginally posted by ninjasaurusrex Quote
LOL im very very confused now...

i put my 50 1.7 and took a picture and then my 18-55 and took a picture at ~50 and its the same...so what's this crop factor nonsense..lol
Of course it's the same, the crop factor applies to the sensor size not to the lens you use, wheter or not the lens was designed for FF or crop. So 50mm on a DA lens is the same as 50mm on a FA lens if used on the same camera.
03-05-2012, 05:50 PM   #10
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but why do people say having a FF lens on a crop factor is like having a longer focal length..is that not true?
03-05-2012, 05:52 PM   #11
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QuoteOriginally posted by ninjasaurusrex Quote
but why do people say having a FF lens on a crop factor is like having a longer focal length..is that not true?
That statement is ambiguous. A FA50 on a K-5 seems like a longer lens than when that FA50 is on a 35mm film camera. Nothing to do with the lens, it's because you've changed bodies (and sensor sizes). However a DA50 and a FA50 on a K-5 have the same FOV.
03-05-2012, 05:58 PM   #12
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i think i understand...

two lenses on the same camera will look the same. but if i want a picture to look similar taken from a 50mm on an apsc i would need a ~75mm on a FF?

so me taking test shots at ~115mm was all in vain..hahah
03-05-2012, 06:01 PM   #13
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QuoteOriginally posted by ninjasaurusrex Quote
i think i understand...

two lenses on the same camera will look the same. but if i want a picture to look similar taken from a 50mm on an apsc i would need a ~75mm on a FF?

so me taking test shots at ~115mm was all in vain..hahah
Yes and yes, lol. Oh well, it's far from obvious and hardly anyone in the general photo taking public understands crop factors.
03-05-2012, 06:07 PM   #14
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Forget the crap factor...
Test the M 50 with a group of three people before the shoot, and you'll find with just a few metres of room between the camera and the subjects, you'll get a very decent result with your existing lens.
But if you want to try something different, with AF, I'd rent the cool DA 40 Ltd or FA 31 Ltd and shoot with enough depth of field to render each person in the shot sharply - preferably with a good separation between the subjects and the background for better DoF control.
03-05-2012, 06:08 PM   #15
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looks like i'm going to rent the 31 FA Ltd. thanks for all your help
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