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12-20-2009, 12:49 PM   #91
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QuoteOriginally posted by Class A Quote
An equivalence is an equivalence. It doesn't break down for some cases.
True, What I should have said, the equivalence can lead to misleading visceral reactions. Yes, assuming your math is correct, a 40/28 works out to a 60/4.3 in FF digital terms. But what are we to make of this? Unless we have actual experience with what a 60/4.3 can do on FF digital, how does this help us understand what the 40/2.8 can do on APS-C? So what actually happens in practice is, we see the f/4.3 and freak out, since our only experience is with APS-C digital. So appealing to a format few of us have experience with just ends up being misleading, even though of course completely correct.

QuoteQuote:
I believe that many people mistake an APS-C f/2.8 with the FF f/2.8, i.e., think they can get less DOF than they can really get.
Could be - like I said, it depends on if you happen to have experience with FF. If you don't, than that comparison just misleads. I know what kind of DOF f/2.8 gives me on APS-C; comparing to another format I have little experience with doesn't clarify that.

Anyhow, my impression is that at close focus distance, I get as shallow a DOF as I might reasonably want from my DA40/2.8. But I am happy to have my manual 50/1.7 for the fairly rare situations when I want to get shallower DOF at longer distances. If you're a shallow DOF junkie, indeed, that will be an issue more often.

QuoteQuote:
Scale this down to P&S sensor formats and then suddenly pretty much everyone knows how difficult it is getting thin DOF on such cameras even though the lenses often are specified as f/2.8 as well. Their FF equivalent f-ratio is much higher.
Right - the difference between APS-C and a typical P&S is far greater than the difference between APS-C and FF in this respect.

12-20-2009, 12:53 PM   #92
Damn Brit
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QuoteOriginally posted by Class A Quote


Why didn't you take a picture instead of making this comment?
Who says I didn't?
12-20-2009, 01:44 PM   #93
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The question is really what you are used to. People who are used the 35mm format really do need to think about equivalences to get the same (similar) effects on APS-C to what they are used to on film. I struggle in general to get more depth of field into my photos -- I hate where an important part of my photo is out of focus, just because I shot too wide an aperture. My perception is that full frame will tend to exacerbate the problem.
12-20-2009, 01:51 PM   #94
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QuoteOriginally posted by GeneV Quote
It occurs to me that some of us old-time Pentax owners need to change our paradigm about the 50mm 1.4 or 1.8. These lenses were dirt cheap because they were the kit lenses of their day. Almost no one bought an SLR without one, and they were manufactured in huge volumes.
That is absolutely true. And I can only subscribe to your view. The 50mm was a commodity in film days, but today it is a specialist lens.

QuoteOriginally posted by GeneV Quote
It also seems to me that the SLR also held a different place in the market back then. Many people I know who owned a film SLR have opted for some digital replacement other than an interchangeable lens SLR. I'm sure that someone with a better finger on the pulse of the industry can confirm or refute this, but it seemed that when I went to weddings, graduations and other events in the film days, there were SLRs around far more necks than today. People today seem awed by a digital SLR..
The facts are, that the DSLR market is just exploding beyond anything, the industry had hoped for and way beyond they ever achieved in film days. If in film days it came out, that basically every household had a SLR (which is an exagerration, I know), than that was due to the long lifecycles and ownership of the same SLR over decades. Sooner or later a SLR would just "drop-in".

Today the DSLR growths is way higher, than it ever was in film days and it will take much less years to get a saturation. On the other hand the lifecycle of DSLRs seem to be very short (at least over the last decade) so that the need for replacements is probably around ten times as high as it used to be.

Ben

12-20-2009, 03:08 PM   #95
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QuoteOriginally posted by Ben_Edict Quote
That is absolutely true. And I can only subscribe to your view. The 50mm was a commodity in film days, but today it is a specialist lens.



The facts are, that the DSLR market is just exploding beyond anything, the industry had hoped for and way beyond they ever achieved in film days. If in film days it came out, that basically every household had a SLR (which is an exagerration, I know), than that was due to the long lifecycles and ownership of the same SLR over decades. Sooner or later a SLR would just "drop-in".

Today the DSLR growths is way higher, than it ever was in film days and it will take much less years to get a saturation. On the other hand the lifecycle of DSLRs seem to be very short (at least over the last decade) so that the need for replacements is probably around ten times as high as it used to be.

Ben
That is interesting. Do you know of any industry statistics on households with film SLRs say 25 years ago vs DSLR? As unscientific as it may be, I know that in my college days, about half my friends had an SLR. Now, I have zero friends with SLRs. I've attended four larger weddings this year (with 70-150 people there), and I was the only unpaid attendee with an SLR at any of them. At my tiny wedding in 1979, two people out of twenty (10 couples) who attended had an SLR. Last Friday I was at the annual ball for an industry with which I work. The only other SLR there was owned by a pro (and it was a K20d, no less). Again, this is all anecdotal and may be way off, but jaws seem to drop when an SLR comes out.

I did a quick Google to try to answer my question. This article seems to indicate that DSLR market penetration is low, but growing. Kids and Income have Greatest Influence on Household Ownership of Cameras and Imaging Related Products . Perhaps the reason for my perception is that the recent DSLR industry success was preceeded by a huge slump in film SLR and is just now picking up. Death of the DSLR Camera - Gearlog . The graph in that article indicates that film SLRs peaked about 25 years ago at 20% of the camera market, and tanked at about 6% in the late 90s. According to those articles, current figures for DSLR sales are 8-10% of the camera market, so we probably are still at half what the SLR market was the last time I bought a film SLR.
12-20-2009, 03:18 PM   #96
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I would venture to say that we are wittnessing a polarization situation where people either make do with cell phone cameras, or move to SLRs. Why someone would go for a twelve megapixel point and shoot is beyond me and I think in the not distant future, they will vanish, as the cameras in cell phones will be close enough to make them redundant. On the other hand, there will always be a place for the bigger sensored cameras, be the micro 4/3rds, APS-C or Full Frame, for those who want better iso, features, etc.
12-20-2009, 03:30 PM   #97
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QuoteOriginally posted by Rondec Quote
Why someone would go for a twelve megapixel point and shoot is beyond me and I think in the not distant future, they will vanish, as the cameras in cell phones will be close enough to make them redundant.
One of those articles I cited seems to say the opposite, but I have also wondered whether the cell phone cameras won't be upgraded a bit and eliminate the P&S.
12-20-2009, 03:45 PM   #98
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QuoteOriginally posted by GeneV Quote
That is interesting. Do you know of any industry statistics on households with film SLRs say 25 years ago vs DSLR? As unscientific as it may be, I know that in my college days, about half my friends had an SLR. Now, I have zero friends with SLRs. I've attended four larger weddings this year (with 70-150 people there), and I was the only unpaid attendee with an SLR at any of them. At my tiny wedding in 1979, two people out of twenty (10 couples) who attended had an SLR. Last Friday I was at the annual ball for an industry with which I work. The only other SLR there was owned by a pro (and it was a K20d, no less). Again, this is all anecdotal and may be way off, but jaws seem to drop when an SLR comes out.

I did a quick Google to try to answer my question. This article seems to indicate that DSLR market penetration is low, but growing. Kids and Income have Greatest Influence on Household Ownership of Cameras and Imaging Related Products . Perhaps the reason for my perception is that the recent DSLR industry success was preceeded by a huge slump in film SLR and is just now picking up. Death of the DSLR Camera - Gearlog . The graph in that article indicates that film SLRs peaked about 25 years ago at 20% of the camera market, and tanked at about 6% in the late 90s. According to those articles, current figures for DSLR sales are 8-10% of the camera market, so we probably are still at half what the SLR market was the last time I bought a film SLR.
Snapshooters rule the world and drive the market... It has pretty much been that way since the 'instamatic' days. Remember Magic Cube flash... Most of our family memories are with those cameras or worse faded poloroids! The Pros/artists/hobbiests were really the ones driving the SLR and DSLR markets for a long time. I agree the dlsr market has gone bonkers with the entry level kits... And one year cycles on camera body replacements

At the same time the P&S snapshooters still own the market, and cell phone cams with direct links to Facebook are the 'Instamatics' of this generation...

here are few recent family snapshots examples on my facebook... which ones do you think got the most comments? And I might add the most glowing comments! And by a huge margin!!!!










I do not even know why I bother pullin out the DSLR anymore...

12-20-2009, 03:55 PM   #99
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QuoteOriginally posted by wallyb Quote
Thinking of an image from an APS-C sensor as nothing more than a cropped version of the same scene in a larger format removes all this confusion, because that's all that it is.
Yes, but you've got to think through all the implications of a crop. If you are stating that a 40/2.8 yields the same DOF independently of sensor format than your are not thinking through the implications of a crop that is enlarged to yield the same size as the bigger format. Marc said it all.

QuoteOriginally posted by Ben_Edict Quote
But this does not explain, why you suddenly transform the 40/2.8 into a f/4.3 lens - not at all.

That was all I wanted to get an explanation for. The DOF discussion does not serve that purpose.
Well, I hope you agree that what DOF range a lens gives you is significant.

A 40/2.8 on APS-C will not give you the same DOF options as a 60/2.8 on FF. Most people are used to apply the crop factor to the focal length (40 -> 60 FF-equivalent) but fewer don't do this for the maximum aperture f-ratio (f/2.8 -> 4.2-FF equivalent).

Also, note that the FF-equivalent maximum aperture f-ratio is also the one to be used if you want to find out how "fast" (in the sense of what amount of light is allowed through by the lens, i.e., w.r.t. exposure as opposed to DOF) an FF-equivalent lens of a particular lens used on APS-C would be.

One must be careful not to confuse this with swapping the same lens from an APS-C camera to an FF camera. The equivalent focal length and widest aperture f-ratio (both obtained by multiplication with the crop factor) are meant to indicate what lens on an FF camera would produce an equivalent image.

QuoteOriginally posted by Damn Brit Quote
Who says I didn't?
Instead, Gary, instead not in addition to.
12-20-2009, 04:07 PM   #100
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QuoteOriginally posted by commo Quote
Did anyone answer the OP's hood question... I didn't see the answer...
Yes, please. Is there anyone who could answer the OP's hood question (What hood would be appropriate to use for the FA 50/1.4 when used on APS-C?)?

QuoteOriginally posted by Marc Sabatella Quote
Unless we have actual experience with what a 60/4.3 can do on FF digital, how does this help us understand what the 40/2.8 can do on APS-C?
I believe many members of this forum will have that FF experience.

I think awareness of the fact that you need to transform the widest aperture ratio as well when converting lenses between APS-C and FF land gives an appreciation of the bigger range of options FF land holds. You not only get wider lenses but also faster (thinner DOF) lenses in FF land (even though the numbers don't look faster).

But in principle we completely agree.

Last edited by Class A; 12-20-2009 at 04:13 PM.
12-20-2009, 04:11 PM   #101
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QuoteOriginally posted by Igilligan Quote
here are few recent family snapshots examples on my facebook...
Are these the same kids in all four images? Number 1 & 3 make it hard to guess.

Number 2 & 4 are beautiful portraits and my favourites no matter what camera you've used.
12-20-2009, 04:19 PM   #102
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QuoteOriginally posted by Class A Quote
Are these the same kids in all four images? Number 1 & 3 make it hard to guess.

Number 2 & 4 are beautiful portraits and my favourites no matter what camera you've used.
As I expected Class A... you are in the minority again! The wifes cell phone pics are all the rage on the facebook! I think the other two may have 1 comment if that! Oops strike that... none!

But thanks for being so wrong yet again, and supporting my wasted time with the dslr~
12-20-2009, 04:27 PM   #103
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QuoteOriginally posted by Class A Quote


Instead, Gary, instead not in addition to.
Same reason you didn't.
12-20-2009, 04:29 PM   #104
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QuoteOriginally posted by Igilligan Quote
As I expected Class A... you are in the minority again! The wifes cell phone pics are all the rage on the facebook! I think the other two may have 1 comment if that! Oops strike that... none!

But thanks for being so wrong yet again, and supporting my wasted time with the dslr~
There's obviously a lot more thought gone into the composition of the cell phone images,
focus isn't everything.
12-20-2009, 04:52 PM   #105
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QuoteOriginally posted by Igilligan Quote
Jeff, do still have your FA43? If so, why on earth would you even be considering throwing money away on the "Plastic Craptastic" (just kidding of course)? Surely it is not for speed, as the 1.4 -2.0 is inconsistent at best. And soft as puddin' at worst

With your lens collection, if speed is what you are looking for... spending that money on a cosina 55 1.2 or any of the Pentax 50 1.2... or even cheaper a Smc tak 50 1.4... Or A50 1.4 would be a good option

Unless of course money is absolutely no object for you. If so, disregard my comments.

Do you have the FA 77 yet? Look at me, I am spending your money for you.

Those with money, do... Those without, dream...
All I can say is LBA. As I was talking with the gal behind the sales counter I kept asking myself the same question, why the 50 when i have the limited 43. makes no sense does it. And yes I do have the 77, that is a joy to use. (no regrets what so ever shelling out the cash on any of my limiteds, 35 macro, 43, or 77) Here's one with the 35 macro
Jeffhttps://www.pentaxforums.com/forums/attachment.php?attachmentid=49932&stc=1&d=1261352989
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