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10-11-2008, 10:53 PM   #1
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A Classic Focal Length Kit

I can't help but to notice that most K1000 for sale on E-bay comes with a M28/2.8, M50/2, and a M135/3.5. As a result there is abundance of these prime available. I am guessing these are just very popular focal lengths and many K1000 kits came with them.

There must be something fundamental about these focal lengths. So why are these focal lengths important?

To built a kit today for our APS-C cameras what would be the most logical kit?

@ 28mm - We don't have a DA 17.5 and would the DA12-24/4 be a good alternative?

@ 50mm - FA31/1.8 comes close to 50mm

@ 135mm - FA85/1.4 comes close but the FA77/1.8 is smaller and cheaper

How do you feel about a kit comprising of the DA12-24/4, FA31/1.8, and FA77/1.8? How adequate do you think this kit be?

10-12-2008, 12:06 AM   #2
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QuoteOriginally posted by leeak Quote
There must be something fundamental about these focal lengths. So why are these focal lengths important?
I think it's largely historical accident. I mean, sure, you want something wide angle, something roughly "normal", and something in the short-medium telephoto range for portraits or other purposes. But I don't know that would be any reason to really shoot for those exact focal length eqivalents as opposed to some other wide angle, normal, and short-medium telephoto focal lengths.

With that in mind:
QuoteQuote:
@ 28mm - We don't have a DA 17.5 and would the DA12-24/4 be a good alternative?
Well, it's a zoom, not a prime, and much larger and more expensive than the 28 was. Unless you feel you *need* a lens that wide, I would think the DA21 would be more comparable to what the 28 was. the recently announced DA15 could turn out to be interesting, too.

QuoteQuote:
@ 50mm - FA31/1.8 comes close to 50mm
True. It's quite expensive, though, and much larger. You might also consider the FA35/2, or even an M28/2.8, as your "normal" lens.

QuoteQuote:
@ 135mm - FA85/1.4 comes close but the FA77/1.8 is smaller and cheaper
There is also an M85/2 that is cheaper still. And an M100/2.8 that is even cheaper. If you are thinking primarily portraits, then 100 might be on the long side (more like 150 on film), but the extra length makes it more suitable for many other purposes. If you are thinking about portraits primarily, the DA70 would also be a very good choice.
10-12-2008, 07:25 AM   #3
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QuoteOriginally posted by Marc Sabatella Quote
I think it's largely historical accident. I mean, sure, you want something wide angle, something roughly "normal", and something in the short-medium telephoto range for portraits or other purposes. But I don't know that would be any reason to really shoot for those exact focal length eqivalents as opposed to some other wide angle, normal, and short-medium telephoto focal lengths.
I think it has as much to do with 28mm being the widest angle lens that could still be made cheaply, and the 135 being the longest telephoto that could both be made cheaply and wasn't too long for people to reasonably use.
I worked for a camera store chain called Astral Photo back in the mid 1980s, and we pushed more 28mm/135mm kits out the door than any other optical product with the exception of standard lenses.
And they were cheap.
10-12-2008, 07:25 AM   #4
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QuoteOriginally posted by ChrisPlatt Quote
You can probably pick up a nice K1000/28/50/135 kit for around $200.

A digital SLR with equivalent focal lengths will cost several times that...

Chris
And film will start to eat into the money saved immediately.......

10-12-2008, 09:17 AM   #5
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QuoteOriginally posted by Wheatfield Quote
And film will start to eat into the money saved immediately.......
If you shoot B&W, process and scan yourself, the cost is not that great, and it is a lot of fun. Film isn't dead, it is just letting the new kid on the block do the heavy listing.

10-12-2008, 09:19 AM   #6
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That said, I just ordered an A24/2.8 to go along with the 31 and 77 for my K10d. I may look for an M20/4 for those times I want to go just a little wider.

I agree, carrying a small kit with 2 or 3 primes is an enjoyable thing.
10-12-2008, 09:34 AM   #7
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Its interesting how popular the 135mm once was. It kind of fell out of vogue though. Zooms and the popularity of the 85mm (on full frame bodies) are mainly responsible.

What has made all the lens arithmetic a hassle is all the different factors all the manufacturers have given us with crop bodies: 1.3X, 1.4x. 1.6x, 1.7x etc...
10-12-2008, 11:23 AM   #8
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I can understand why a 28mm and 50mm equivalent lens being useful, but not 135mm. @135mm (85mm on a APS-C), isn't it too long for portraits and not long enough as a tele? Maybe it is the cost of economics. It's interested how archaic and random this is. = )

10-12-2008, 11:32 AM   #9
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Those are pretty much the classic primes with a digital also, I mean, what's a multiplier between friends anyway?

28mm supplanted the 35mm as the 'wide' when they figured out how to make them cheaper. The 28 gives you a real W I D E feel yet isn't impossible to handle relative to convergences and bends.

The 135 was a reasonable compromise between a long-ish lens that was still hand holdable. The 75/80/85 length comes to us via 120 6x6, the 105 via 6x9, and the 135 was used with plate cameras. So each had a long history by the time 35mm SLRs came around.

For digital, I'd actually drop the 135 in favor of a 70-90 or so. But then I've never got along with the 135 focal length. I love how the 28/35/50 series works, whether film or digital
10-12-2008, 01:25 PM   #10
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the thing that is interesting is that people think of "normal" forcal length more is the sense of angle of view than the equivalent perspective to the eye, I'm not sure if i understand correctly that the 50 mm lens has the same perspective view point as our eyes and in 35mm format that was a happy coincidence but now well my old fujifilm camera had to be at 200mm (135 equiv.) to actually be at 50mm and have a fairly natural perspective which i start to find more important than the actual angle of view (magnification / zoom)
10-12-2008, 01:59 PM   #11
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The 50mm on a normal film or FF digital camera is almost the same view as one human eye (not both)...
10-12-2008, 02:54 PM   #12
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QuoteOriginally posted by leeak Quote
I can understand why a 28mm and 50mm equivalent lens being useful, but not 135mm. @135mm (85mm on a APS-C), isn't it too long for portraits and not long enough as a tele? Maybe it is the cost of economics. It's interested how archaic and random this is. = )
It's a bit of an oddball focal length on film, I would agree, but I think it's value is that it was *just* short enough to still make a decent portrait lens, and *just* long enough to have some use as a telephoto. Of course, most people would probably have better off with both a 100 for portraits and a 200 (or 300) for other telephoto applications. But that's two lenses where one will sort of do. And 135/2.8 can indeed be made relatively small.

I am using my M100/2.8 a lot on digital, which is only a little longer than 135 on film. I actually find it not a bad length for portraits, and really ideal for concert photography, but of course still too short to be useful for wildlife. Given that a 135 is also too short for wildlife, I find the 100 an all-round better focal length for me than 135 on APS-C, which suggests I would have liked the 135 just fine on film. But the M100/2.8 is even smaller than the M135/3.5, and of course much smaller than any 135/2.8. So I'm quite happy at that end of the spectrum.

I do wish there were a cheap, fast, "normal" lens for APS-C, though. As it is, I settle for using the M28/2.8 and DA40/2.8. One is a bit shorter than 50 was, one a bit longer, and actually I like having that spread available, and suspect that 50 equivalent itself wouldn't interest me as much. But of course, f/2.8 isn't f/2, much less f/1.7 or f/1.4.
10-12-2008, 02:57 PM   #13
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The 28/55/135 is the classic newsman's set. Notice that 28 is almost exactly 1/2 the focal length of the 55, and 135 is just a bit longer. On film, the 28 is almost the perfect indoor group lens. I find that 24mm (16mm on APS-C) tends to fatten the people on the end of the line. Sometimes they object. The 28mm tends not to do this as much, perhaps because one is stepped back further to get everyone in.

55mm was the original maker's lens for many, many 35 mm camera makers, not just Pentax. My first Pentax (THE first Pentax) came with a 55/2.2 lens as standard. In those days 35mm was wide angle and 28mm was WOW!

I shot a lot of soccer and track and field with the 135mm f/3.5 in both the Takumar and M versions. It was a relatively good length for that.
10-12-2008, 03:01 PM   #14
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QuoteOriginally posted by simons-photography Quote
the thing that is interesting is that people think of "normal" forcal length more is the sense of angle of view than the equivalent perspective to the eye, I'm not sure if i understand correctly that the 50 mm lens has the same perspective view point as our eyes and in 35mm format that was a happy coincidence but now well my old fujifilm camera had to be at 200mm (135 equiv.) to actually be at 50mm and have a fairly natural perspective which i start to find more important than the actual angle of view (magnification / zoom)
I hate to bring this up here, but once more, for the record: perspective has *nothing* to do with focal length, and everything to do with distance to subject. Of course, we are accustomed o thinking in terms of focal length because, with a fixed film/sensor size, focal length trnalsates directly to angle of view, which in tunn influences what we think of as an appropriate subject distance. But if lens A on camera 1 produces the same angle of view as lens B on camera 2, then those lenses have exactly the same perspective.

All of which is to say, if a given camera/lens combo has the same angle of view as a 50mm on film, then it has the same perspective. Perspective was a fixed and known thing in the art world centuries before the invention of photography, and nothing has changed since.
10-12-2008, 03:23 PM   #15
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QuoteOriginally posted by Marc Sabatella Quote


I am using my M100/2.8 a lot on digital, which is only a little longer than 135 on film. I actually find it not a bad length for portraits, and really ideal for concert photography, but of course still too short to be useful for wildlife.
I'm getting huge mileage out of my 85/1.4 these days. I'm finding it wonderful for portraits, better than I found the focal length to be on film, in fact.
I found the 77 to be a better portrait lens on digital than film as well.
Perhaps that IQ loss at distance is good for something.
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