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05-22-2013, 02:08 AM   #1
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The relationship between Limited FA lenses and Medium Format standards.

The relationship of pentax limited FA lenses and Medium Format standards.


i have borrowed a KIEV 88 (hasselblad clone) from a friend, and it has
a 80mm f2.8, a 65mm 3.5 and a 150mm f2.8

in the square format of ratio 6:6 to get the same values as 35mm equivalents, you have to divide by 1.96
acording to what i read online somewhere...

so that leaves us at...

the:
65mm f3.5 is an equivalent of 33mm f1.8 ( FA 31mm F1.8 )
80mm f2.8 is an equivalent of 41mm f1.4 ( FA 43mm F1.9 )
150m f2.8 is an equivalent of 77mm f1.4 ( FA 77mm F1.8 )


some people say the 43 is made to go along with the diagonal of the 35mm, but the truth is, before the 43mm went along with the diagonal of 35mm film, the medium format 80 mm 6x6 was alredy doing that.


(all numbers rounded up)
now compare those values to the current offer of pentax limiteds.


Since the low F Number of the limited lens and focal lens is impossible to replicate using a zoom lens
(the max i found out is at f2.8)
i believe the pentax engineers have tried (and had sucess) of replicating the mistical awesome look of medium format
but on a lower resolution medium.


The look i see from some photos of the limited lenses have alredy reminded me of some medium format shots
so i decided to make this comparsion, and i think that's why the lens are so special.
it's imaginary compares, in terms of composition, subject compreesion, depth of field and point of view to a medium format camera in my humble opinion.

If this is true,the limited have stoped being the
"odd focal lens" and are now the "professional standard focal lenghts"

Think about it...


Last edited by Akarak; 05-22-2013 at 06:41 AM.
05-22-2013, 02:38 AM   #2
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I thought about it.

But why are they still magical on Cropped FOV?

Answer that!
05-22-2013, 02:43 AM   #3
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QuoteOriginally posted by usmcxm35 Quote
I thought about it.

But why are they still magical on Cropped FOV?

Answer that!

because a crop doesn't mess your compression, just field of view, it just shows less of the said magic basicly.
05-22-2013, 03:09 AM   #4
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Oops, I was just implying that the FA limited trio are magical regular less of what focal length they are.
Not trying to start anything.
Cheers.

05-22-2013, 04:52 AM   #5
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Very interesting. When I bought my Pentax DSLR I already had my F28 and F50 I used on film. And after applying the 1.5 CF I thought "Hey, now I have those famous 43 and 77mm lenses" haha (although the 43 is f/2.8)
05-22-2013, 05:09 AM   #6
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QuoteOriginally posted by carrrlangas Quote
Very interesting. When I bought my Pentax DSLR I already had my F28 and F50 I used on film. And after applying the 1.5 CF I thought "Hey, now I have those famous 43 and 77mm lenses" haha (although the 43 is f/2.8)

i also though of that but onfortunaly it's not the same, there's also a depth of field conversion, and that changes the whole composition when measuring agaisnt a fullframe 35mm


this observations i've noticed and published here are meant to be FULL FRAME FA limiteds vs Medium Format Standards.
05-22-2013, 05:26 AM   #7
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QuoteOriginally posted by Akarak Quote
i also though of that but onfortunaly it's not the same, there's also a depth of field conversion, and that changes the whole composition when measuring agaisnt a fullframe 35mm


this observations i've noticed and published here are meant to be FULL FRAME FA limiteds vs Medium Format Standards.
I know, but I actually prefer the larger DoF of APS-C. Makes it easier to shoot wide open, take advantage of available light, etc.
About the 43mm FL, I found it to be a bit "hysterical" at first. Later on I got a 24mm (36mm equiv) and it felt much more natural.
05-22-2013, 08:13 AM   #8
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What is a "standard" with medium format film? You imply 1:1 is. But there are so many other projections on a 120 roll of film. And you borrowed a Kiev 88. Is that your only experience with medium format film?


Last edited by tuco; 05-22-2013 at 08:19 AM.
05-22-2013, 08:44 AM   #9
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QuoteOriginally posted by tuco Quote
What is a "standard" with medium format film? You imply 1:1 is. But there are so many other projections on a 120 roll of film. And you borrowed a Kiev 88. Is that your only experience with medium format film?
Fortunaly this is not my first time with medium format

The other said projections of 120 film hve their own set of lenses.
This camera is 6x6 (max) as i just haev a 6x6 back

But eevn with that, there's the conversion numbers online from 6X7 to 35mm and 6*5/4 too

look it up and do your own math
05-24-2013, 03:16 PM   #10
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now one finds this intresting?
05-24-2013, 03:26 PM - 2 Likes   #11
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Focal length is focal length...

Cropping is cropping...

DOF (at base) is determined by physical aperture, magnification, and viewing distance...

So, I would postulate the relationship of the Limiteds to Medium Format is that they are lenses with inadequate image circle to be used with 120 film...


Steve


(...good thing I don't drink or do drugs...this could have gotten out of control...)

Last edited by stevebrot; 05-24-2013 at 03:37 PM.
05-24-2013, 06:09 PM   #12
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QuoteOriginally posted by Akarak Quote
now one finds this intresting?
I find it quite interesting, even though the numbers don't match perfectly. If you divide the FA focal lengths by the same 1.96, I bet you can predict the results.

31/1.96 = 15.8
43/1.96 = 21.9
77/1.96 = 39.2

So we have the DA Limited focal lengths, +/- 1 millimeter.

Interesting stuff, to be sure. Of course, the company could just explain the idea behind the focal lengths, if they felt like it.
05-24-2013, 06:46 PM   #13
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QuoteOriginally posted by fuent104 Quote
I find it quite interesting, even though the numbers don't match perfectly. If you divide the FA focal lengths by the same 1.96, I bet you can predict the results.

31/1.96 = 15.8
43/1.96 = 21.9
77/1.96 = 39.2

So we have the DA Limited focal lengths, +/- 1 millimeter.

Interesting stuff, to be sure. Of course, the company could just explain the idea behind the focal lengths, if they felt like it.
This is interesting becouse it kinds of confirms what Akarak was saying... I never worked with a medium format and I really dont think I ever will/ need to.
05-24-2013, 06:59 PM   #14
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QuoteOriginally posted by Akarak Quote
now one finds this intresting?
Not even slightly I'm afraid.
05-24-2013, 09:38 PM   #15
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QuoteOriginally posted by dadipentak Quote
Not even slightly I'm afraid.
I find it interesting that you felt the need to make a post stating that you aren't interested in the topic. To each his own.

I am still interested in this. Akarak, can you post the source of the 1.96 number, or describe it in detail?
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