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09-06-2009, 06:44 PM   #61
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QuoteOriginally posted by jslifoaw Quote
The comparison between the 50-135 and 70-200 Canon is also unfair because the Canon lens is effectively faster since for any AOV, it can stop down one stop to produce the same image as the 50-135. If you consider the 70-200 F4 Canon, you would observe a much smaller difference in size, weight, and cost. In fact, at wide angles, you would often notice that FF lenses are effectively smaller than APS-C lenses, unless you plan to use those lenses at smaller apertures most of the time in which case compact lenses like the DA21 do not have a real match (i.e. think about how small and cheap an FA31 would be if it was an F4.5 lens instead of F1.8).
Never thought of it that way. Thanks for the new perspective on the issue.

09-07-2009, 10:08 AM   #62
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I don't believe that aps-c sized DSLR's are going to die out. The overall trend has been towards smaller cameras. All the manufacturers have invested a lot into lenses and sold a lot of cameras. My own feeling is that the FF cameras are really aimed at the medium format market offering a less expensive and smaller/lighter alternative. While the larger sensor has the IQ advantage right now (for those willing to pay the price), it's only a matter of time before extremely high IQ sensors will be around for in aps-c and smaller. In the future, I think formats like micro 4/3 will become much more of a competition than FF. To be honest I look forward to that. I hiked up a local mountain with my K10D this past weekend with 2 lenses. I'm getting older and prefer not to be carrying anything more than needed. I noticed the weight more than I thought I would. I noticed one other thing. 20 years ago I would have seen several people with film SLR's along the trail and on the summit. Saturday I saw one other guy with a Canon Rebel. Just about everybody had a digital P&S or bridge camera.
09-07-2009, 07:07 PM   #63
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I have to say, I could care less about FF, except for one thing that almost no one ever talks about. That being, the expansion or extension (I don't know the right terminology) of the lenses so that a 50 mm becomes an 85 (or somewhere around there), etc. Not only do you always have to make this calculation in your head, but it seems to me that you can never get as wide as you would on a FF (I am shopping around for a wide-angle right now, so I have been thinking about these things). Or are the DA calculated the right way? That just occurred to me. In that case, their wide angles would be much better to get than older model wide angles.
09-07-2009, 07:26 PM   #64
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QuoteOriginally posted by jess Quote
I have to say, I could care less about FF, except for one thing that almost no one ever talks about. That being, the expansion or extension (I don't know the right terminology) of the lenses so that a 50 mm becomes an 85 (or somewhere around there), etc. Not only do you always have to make this calculation in your head, but it seems to me that you can never get as wide as you would on a FF (I am shopping around for a wide-angle right now, so I have been thinking about these things). Or are the DA calculated the right way? That just occurred to me. In that case, their wide angles would be much better to get than older model wide angles.
For all intents and purposes, APS-C has no problems with wide angle coverage, with the added bonus of being about to use filters (Sigma 10-20 vs any FF lens that is 15mm). For the ambitious, you can get 12mm for FF, but that is a fairly extreme FL.

The main issue that I and a fair number of others have is that there are few fast wide lenses to match relatively simple 35mm pairings such as a 20/2.8, 24/2.8, 28/2.8, 35/2, or 50/1.4 because of the difficulties in offering lenses with 2/3 the focal length AND f-number. I don't really care about resolution or noise (I'm still very happy with two 6MP bodies), and FF has no advantage once you hit around 135mm.

09-07-2009, 09:45 PM   #65
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QuoteOriginally posted by jess Quote
I have to say, I could care less about FF, except for one thing that almost no one ever talks about. That being, the expansion or extension (I don't know the right terminology) of the lenses so that a 50 mm becomes an 85 (or somewhere around there), etc. Not only do you always have to make this calculation in your head, but it seems to me that you can never get as wide as you would on a FF (I am shopping around for a wide-angle right now, so I have been thinking about these things). Or are the DA calculated the right way? That just occurred to me. In that case, their wide angles would be much better to get than older model wide angles.
First, people *do* talk about this, all the time. That's one of the main reasons many people want FF: to make it easier to get wide angle lenses.

But really, no one is forcing you to do any calculations in your head. 50mm is 50mm. If you only use APS-C, then it shouldn't matter at all what other focal length might happen to provide the same FOV on FF. So it's not APS-C that makes you do calculations; without FF to compare against, there would be no need to calculate anything. And the mere existence of FF doesn't force you to calcuate anything either. That would be like saying the problem with the metric system is that it forces up to keep calculating how tall we are in meters.

Anyhow, if for some reason you are curious about what focal length on FF with have the same FOV as a given lens on APS-C, it doesn't matter if the lens you aare using on APS-C is DA or not. *All* lenses will have a narrower FOV on APS-C than FF; there is no possible way it could be otherwise. So whether your 50mm lens on APS-C is DA, FA, M, K, or M42, it will have a narrower FOV on APS-C than it does on FF, and you'd need a 75mm lens (multiply by 1.5) to get the same FOV. Again, though, it isn't at ll clear why ou'd be doing that calculation. Just because FF exists mean you have to go around calculating what lenses would give the same FOV on that format as your current lenses. No more than the meter existence of the metric system forces me to go around calculating metric equivalents for all measurements I make.
09-08-2009, 01:31 AM   #66
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I'd like the option of full frame (if I really want to shoot full frame I'll use my film camera) but for most shoots, as has been pointed out, 1.5 crop is by far the better option.
09-08-2009, 05:30 AM   #67
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People talk about the lack of cheap wide angles for APS-C all the time. What they don't say, is that wide angle is very different on APS-C from full frame. 20 mm is pretty wide on full frame and I don't recall any zooms on full frame like the 12-24 is on APS-C. That would be 18 to 36 on full frame and would have been a huge lens.

Truthfully, the real lack of APS-C in my view, is that there aren't cheap "normal" lenses. Something like what the 50 used to be on film. It would be nice if there was a reasonably priced 30 mm-ish lens at f2 (like the FA 35). This would really make a difference.
09-08-2009, 06:18 AM   #68
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I used to shoot with the Canon 17-40 L which was quite good except that, as you said, heavy and huge (compared to Pentax lenses). Never got to try it out, but I imagine it would be quite the lens on FF.

QuoteOriginally posted by Rondec Quote
I don't recall any zooms on full frame like the 12-24 is on APS-C. That would be 18 to 36 on full frame and would have been a huge lens.


09-08-2009, 07:49 AM   #69
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QuoteOriginally posted by Mr. The Guy Quote
non-DA lens are obsolete today.
They're obsolete only because they're out of production.

QuoteQuote:
They're missing features and were designed years ago for film. If you have a digital camera, why on earth do you think that a film lens can ever possibly be a better solution? It makes no sense.
They're missing some features, but interestingly, given the number of non-DA owners here, it looks like most people do find them very usable.

QuoteQuote:
Speed: Unnecessary
Total BS. Maybe the lenses are too fast for you, but lenses are never too fast.

QuoteQuote:
Size: Too big
It is general lens design and has nothing to do with FA vs DA. Small and large lenses exist both in FA and DA. The M 40/2.8 is a lot smaller than the DA 60-250. What's your point?

QuoteQuote:
Price: They're more expensive.
Supply and demand. They're expensive only because they're out of production, and somehow, even your claimed disadvantages were all true, people still want to own them, pushing up prices.

QuoteQuote:
In-camera Corrections: Not supported on non-DA lenses
One of the few reasons to use DA lenses. The others are new coating, QSF, SDM and weather seals. However, being "too fast", "too big", "too expensive" are either incorrect or irrelevant.

QuoteQuote:
It's just a delusional desire by those who for some absurd reason think their old 70's lenses are going to work wonderfully on a digital camera. They're dreaming.
Looking at my 70s SMCT 85/1.8 images and those captured with the DA70, I must say I prefer the 85, and somehow, after CA and Distortion correction, I still find the images from FA35 much better than the DA18-55 and sometimes the DA40. I also bet a lot of people here choose to stay with the FA50 instead of getting the more than twice as expensive, but less than twice better DA55.

Pentax, if you're seeing this, it's time to change your lens directions - having ISO 6400 and SR does not nearly provide enough justification of making most of your DA lenses f/2.8 or slower. Also, I (and probably some others) do not want SDM, weather sealing, and a * or limited designation in every single lens.

Just make good DA primes that are fast, screw-driven, non-sealed, in plastic casing, and sell them at non *, non limited prices.



Don't mistaken what I say as a DA hater. I own some very good DA lenses. Just that I have a strong disagreement with you regarding the desirability of FA or older lenses, *especially* the "Speed: Unnecessary" part.

Last edited by wolfier; 09-08-2009 at 08:02 AM.
09-08-2009, 12:02 PM   #70
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QuoteOriginally posted by Rondec Quote
Truthfully, the real lack of APS-C in my view, is that there aren't cheap "normal" lenses. Something like what the 50 used to be on film. It would be nice if there was a reasonably priced 30 mm-ish lens at f2 (like the FA 35). This would really make a difference.
Agreed when it comes to Pentax-branded offerings there isn't anything reasonably priced. I've been very happy with the Sigma 28mm f/1.8 EX Aspherical DG DF Macro, which you can pick up for $370. Do I wish it was physically smaller and cheaper, sure, but otherwise I really like the build quality and the quality of the pictures it takes, and the price is pretty good I think.

However anyone evaluating the Pentax APS-C platform who doesn't consider third party lenses like the Sigma 28mm, will think that there are no reasonably affordable "normals".
09-08-2009, 12:13 PM   #71
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QuoteOriginally posted by wolfier Quote
Just make good DA primes that are fast, screw-driven, non-sealed, in plastic casing, and sell them at non *, non limited prices.
Agree, agree, agree!
Where are the consumer grade affordable DA prime lenses?
09-08-2009, 12:27 PM   #72
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QuoteOriginally posted by nater Quote
Agreed when it comes to Pentax-branded offerings there isn't anything reasonably priced. I've been very happy with the Sigma 28mm f/1.8 EX Aspherical DG DF Macro, which you can pick up for $370. Do I wish it was physically smaller and cheaper, sure
And I would say that is the point. For FF, you can have a normal lens that is fast, small, and cheap. For APS-C, you have to accept bigger, slower, and more expensive. I believe that is kind of inherent in the design of the typical DSLR camera, and in particular, the registration distance (from mount to sensor). A mirrorless APS-C design could be made with a shorter registration distance, and would then have a faster/smaller/cheaper normal.

And to make matters worse, due to the whole "equivalence" business being discussed in another thread, you actually need a normal lens for APS-C that is *faster* than the equivalent for FF in order to get the same performance. That 28/1.8 is the "equivalent" of a 42/2.5. You'd need an f/1.4 normal on APS-C just to match the performance of an f/2 on FF. Meaning you're looking at bigger and more expensive still. And forget getting the equivalent of an f/1.4 - an f/1.0 normal for APS-c just isn't going to happen.
09-08-2009, 12:29 PM   #73
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QuoteOriginally posted by Zav Quote
Agree, agree, agree!
Where are the consumer grade affordable DA prime lenses?
My guess is, not going to happen. Consumer grade primes were popular (and necessary) decades ago because zooms either weren't available yet, or were just terrible. The typical consumer actually bought primes, because there was little choice. Today, the typical consumer buys zooms, and would continue to do so even if consumer grade primes were available. That's both because the quality of consumer zooms is vastly better than it was in the past, and because the majority of photographers just prefer using zooms.
09-08-2009, 01:09 PM   #74
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I'd say that we're beginning to see some affordable "normal" lenses from some manufacturers, namely the Nikon 35mm f/1.8 which gets decent reviews and the Olympus 25mm f/2.8 (although not fast, it's a nice compact prime 50mm equiv.). Both of these lenses are sub $300 USD and seem to be selling okay, not flying off the shelves but they're at least out there. I would expect other manufacturers to follow suit if they see others blazing a successful trail. Unfortunately, primes, like Marc said are not real sexy nowadays. They're only appreciated by photographers who value compact, very sharp lenses. Pentax has a beautiful lineup of limiteds, but you're going to pay pretty big dollars for them (that is, unless you compare prices to Canon or Nikon's large primes).
09-08-2009, 06:23 PM   #75
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QuoteOriginally posted by Marc Sabatella Quote
And I would say that is the point. For FF, you can have a normal lens that is fast, small, and cheap. For APS-C, you have to accept bigger, slower, and more expensive....
Actually, the Sigma 28mm is FF as well as APS-C optimized... I think it's size/weight have as much to do with it's close-focus capability as any "DG" specification... for instance, the Sigma 30mm is APS-C only, and f/1.4, yet smaller and lighter (but not a macro lens). Yet, oddly enough, the Sigma 30mm is $70 more expensive than the 28mm. I went with the 28mm over the 30mm for the ability to use it on my old FF bodies, the macro, and was ok with f/1.8 vs. f/1.4 while saving some money. But I do find the pricing somewhat odd.

I'd love it if I could buy more AF primes for under $400 that were also f/2 or below.
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