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05-08-2009, 04:01 AM   #211
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Something I don't understand is why 35 mm negative size? It makes absolutely no sense. Your sensor can be any size, any shape and here we are talking about a sensor the same size as a film negative. And, if bigger is better, why not something a little bigger - maybe 25 percent larger than a film negative.

If there never had been 35 mm film, there would be no discussion and on the other hand, if more people had shot with medium format film, they would not be saying that 35 mm is the pancea that some seem to feel that it is. Medium format has always been the perferred format for top end photographers and as I read Ansel Adams books, I understand that one of his biggest concern was diffraction -- much less of a problem in medium or large format than either APS-C or Full Frame.

05-08-2009, 04:26 AM   #212
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QuoteOriginally posted by Rondec Quote
Something I don't understand is why 35 mm negative size? It makes absolutely no sense.
It's so our beautiful old lenses, all of which were designed for 35mm film, will have the correct FOV and DOF.
05-08-2009, 04:31 AM   #213
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QuoteOriginally posted by cousinsane Quote
IMHO the DOF in that picture is far less than 6 feet.
Based on what? The least it could be in any event is 4 ft. Just counting the sleepers its a lot more than that.

QuoteQuote:
And frankly, I'm not all that interested in DOF calculations. I would love to be able to emulate the wide angle & shallow DOF effect of that picture with my APS body, but I've never seen an example of that being done with an APS body.
So that means it cant be done?

Please note, that to do it on a FF body requires a $1500 prime lens. Where does all this start to become irrelevant on financial grounds, or do you have a few thousand burning a hole in your pocket?
05-08-2009, 06:40 AM   #214
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QuoteOriginally posted by Rondec Quote
Something I don't understand is why 35 mm negative size? It makes absolutely no sense.
The K-mount has been designed for that size and that's the biggest size it can take. APS-C was always a compromise based on a good ratio between performance and price. And entry-level APS-C camera costs less than 500$, you can even find some older models for less than 300$. OTOH the cheapest FF camera is the old 5D that is around 1000-1500$. New FF cameras are around 2500-3000$ *body only*. A bit too expensive for electronic gadgets that loose their value in less than 2 years.

05-08-2009, 06:54 AM   #215
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QuoteOriginally posted by 24X36NOW Quote

APS-C dSLRs are NOT "thicker" than film SLRs to address the need for "telecentric" light paths to the sensor. The sensor is THE SAME F---ING DISTANCE FROM THE LENS AS THE FILM PLANE -
Film is not "as sensitive" to angled, off axis light as is a solid state/micro lensed sensor. Case in point, the Leica had to develop special shaped micro lenses to account for the skewed light of wide angle lenses. The lens is coded to add a software correction as well... so yes there is a BIG FREAKING difference as to the way film and sensors respond to off axis oblique light
Leica M8 Review: 1. Introduction: Digital Photography Review

And for further review:
http://www.cameralabs.com/forum/viewtopic.php?p=14687&sid=3fbb05ba00cb91d195e294ad4bfb8aea
Bob...
So, controversially perhaps, I will assert that this depth of field argument comparing full-frame versus cropped sensors is sterile. With a fixed print size and the cropped sensor as our benchmark you can end up with a smaller DoF if you re-frame by moving the full-frame camera closer to the subject, you can end up with a greater depth of field if you don't re-frame with the full-frame camera (and so objects in the final print are smaller) or you can end up with the same DoF if you re-frame with the full-frame camera by changing lenses but are operating to the same lens budget (which means you can only afford a slower lens).

Last edited by jeffkrol; 05-08-2009 at 07:12 AM.
05-08-2009, 07:04 AM   #216
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QuoteOriginally posted by jeffkrol Quote
Film is not "as sensitive" to angled, off axis light as is a solid state/micro lensed sensor.
A year ago, I talked to a Pentax service technician when servicing my W10, and he showed me the then brand new W60, and explained that the reason they now could provide it with a much wider angle at the wide end of the zoom range, was that the newer sensors now where "shallower", and thus not as sensitive to the angle of the light.
05-08-2009, 07:35 AM   #217
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As I I've said in the past, I'd be fine with an APS-C camera so long as the view finder can match a FF camera (hopefully the K7 does this), but one thing troubles me. I no longer see the 30mm DA* prime on Pentax's lens road map. That means you'd have to buy the $900 FA 31mm Limited if you want a "normal" prime for low light faster then f/2.8. Either that or buy the Sigma 30mm 1.4. I suppose I could do that, but seeing as how primes are what Pentax seem to specialize in it would suck to have to buy a 3rd party lens for that purpose. So is the DA30mm gone for good?
05-08-2009, 07:47 AM   #218
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QuoteOriginally posted by gazonk Quote
A year ago, I talked to a Pentax service technician when servicing my W10, and he showed me the then brand new W60, and explained that the reason they now could provide it with a much wider angle at the wide end of the zoom range, was that the newer sensors now where "shallower", and thus not as sensitive to the angle of the light.
Better, but not perfect. Sensors with microlenses also have issues simply due to optical refraction.

But the main reason that APS cameras are thicker than film cameras is the thickness of the sensor assembly and the LCD which together add about 1cm to the overall flange to rear of camera distance.

05-11-2009, 01:49 PM   #219
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QuoteOriginally posted by jay Quote
Because we're not stupid enough to expect our camera's manufacturer to go into bankruptcy trying to produce 4 lens lines..


Huh??
They are already producing, and have for years, four lens lines; FF, DA, 645, and 67.......
05-11-2009, 01:53 PM   #220
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QuoteOriginally posted by jay Quote
Full-frame sensors are like that. They're lazy. They're big and bulky and use lots of power. They rely on sheer size instead of ingenuity. They require huge lenses, huge bodies, and huge pocketbooks.

APS-C sensors are crafty. They're noticeably smaller -- smaller lenses, smaller bodies (Samsung NX) and less expensive. New technology is easier to apply to APS-C sensors (because of the smaller sensor size), and each year, they get better and better.

Smaller is definitely the new black this season..

You forgot an important issue; APS lenses need to be 50% better than FF lenses on FF in order to get equal results (all things equal). Thats why we have all this whining about lens issues and color fringing.....
05-11-2009, 02:36 PM   #221
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QuoteOriginally posted by cousinsane Quote
Seems the exif is stripped, so I should add that it was taken with a 35/1.4L + Canon 5D.
The flickr tags say it was a 135mm/f2.0. (Which makes it humorous to be talking about the "wide angle" of the image.) I think a decent photographer could get similar results with a K20D and the 77mm f/1.8 Limited.
05-11-2009, 05:09 PM   #222
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QuoteOriginally posted by mattdm Quote
The flickr tags say it was a 135mm/f2.0. (Which makes it humorous to be talking about the "wide angle" of the image.) I think a decent photographer could get similar results with a K20D and the 77mm f/1.8 Limited.

Hmm. If thats true, then you could almost certainly do BETTER on an APSC camera. I think F2.0 is the fastest 135 made, but there are plenty of fast 85's down to F1.2.
05-11-2009, 07:36 PM   #223
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Oops, my bad. Guess I was fooled by the converging railings.

Luckily, digging through his flickr album, it wasn't hard to find a "true" example of wide angle & shallow DOF.

On Black: A family vacation in New York! by NNBB & Alf [Large]

QuoteOriginally posted by mattdm Quote
The flickr tags say it was a 135mm/f2.0. (Which makes it humorous to be talking about the "wide angle" of the image.) I think a decent photographer could get similar results with a K20D and the 77mm f/1.8 Limited.
05-11-2009, 07:49 PM   #224
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QuoteOriginally posted by Art Vandelay II Quote
As I I've said in the past, I'd be fine with an APS-C camera so long as the view finder can match a FF camera (hopefully the K7 does this), but one thing troubles me. I no longer see the 30mm DA* prime on Pentax's lens road map. That means you'd have to buy the $900 FA 31mm Limited if you want a "normal" prime for low light faster then f/2.8. Either that or buy the Sigma 30mm 1.4. I suppose I could do that, but seeing as how primes are what Pentax seem to specialize in it would suck to have to buy a 3rd party lens for that purpose. So is the DA30mm gone for good?
You probably just answered why Pentax is not making the 30mm DA*:

1) Sigma 30mm 1.4
2) DA 35 mm 2.8
3) FA 31mm 1.8 (with no sign of going out of production)

The difference between primes and zooms has lessened a lot over the last few years. So investing in prime options is one thing, but over-investing runs into the law of diminishing returns.
05-11-2009, 08:06 PM   #225
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QuoteOriginally posted by Aristophanes Quote
You probably just answered why Pentax is not making the 30mm DA*:

1) Sigma 30mm 1.4
2) DA 35 mm 2.8
3) FA 31mm 1.8 (with no sign of going out of production)

The difference between primes and zooms has lessened a lot over the last few years. So investing in prime options is one thing, but over-investing runs into the law of diminishing returns.
Maybe. Still no weather-sealed normal. I'm hoping that this is what it's re-tooled as (given the current rumors, that doesn't seem far fetched) and that it has the optical quality to at least equal the DA Limited series.
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