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03-15-2011, 03:49 PM   #46
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QuoteOriginally posted by lesmore49 Quote
No...the Pentax 645D has a sensor larger than a full frame. It's a medium format.
As shown here.

03-15-2011, 04:32 PM   #47
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QuoteOriginally posted by Laurentiu Cristofor Quote
As shown here.
Atually the 645D sensor is 44mm x 33mm, and not the 50.7mm x 39mm that the kodack 3900 sensor is.

It is still larger then a 135 format frame though (36mm x 24mm)

Note that 645 format is 56mm x 41.5mm, so the 645D sensor is cropped in comparison.
03-15-2011, 06:02 PM   #48
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The 645D has a "cropped medium format" sensor. I.e the 645D sensor is smaller than a traditional 645 sized film, but, the sensor is still 1.7 times larger than a 35mm "full frame" sensor.

QuoteOriginally posted by lesmore49 Quote
No...the Pentax 645D has a sensor larger than a full frame. It's a medium format.
Correct

QuoteOriginally posted by Spare Tire Quote
Pentax 645D is a crop sensor.
Cropped medium format. Which is still bigger than full frame.
03-15-2011, 06:30 PM   #49
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My recently-won Halina 4-4 should arrive any time now. Well, I paid for cheapest shipping from UK to California, so I *might* see it sometime this year. Anyway, it's a MF film-eater with two frame masks: 6x6cm and 4x4cm. The latter is super-slide size, popularized later by 127-40 film cameras. So its 4x4cm frame is certainly a 'cropped' MF format -- and is still bigger than the 645D frame. (I may try to fabricate a 645 mask for the Halina.)

Let's see, compared to a 645 frame (69.7mm diagonal), the 645D frame (55mm diagonal) has a crap.factor of ~1.3x (1.27x actually) and the Halina 4-4 frame's (56.6mm diagonal) factor is ~1.2x (1.23x actually). And the Kodak 3900 sensor's (64mm diagonal) factor is ~1.1x (1.089x actually). So they're all crop frames. BTW, FF has a diagonal of 43.4mm, and my APS-C dSLR's frame diagonal is 28.1mm. Y'all are invited to do the crap-factor math.

The question is, does that matter, and how? But that's for another thread. My point is (do I actually have a point?) that the trade-offs include resolution, frame pixel density and thus noise, but also lens effects. Images just look different when shot on LF, MF, 135/FF, 135/HF (APS), and smaller frames. Larger frames allow more control of the optics. Smaller frames allow more freedom in shooting. Control vs freedom -- the age-old class struggle!

[/me raises clenched fist in support of... P&S's ??]


Last edited by RioRico; 03-15-2011 at 06:36 PM.
03-16-2011, 01:14 AM   #50
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QuoteOriginally posted by lesmore49 Quote
No...the Pentax 645D has a sensor larger than a full frame. It's a medium format.
But it's crop compared to the size of a medium format film image.
03-16-2011, 08:03 AM   #51
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Same arguments apply: people who want to use the full image circle of their FF lenses also want to use the full image circle of their 645 lenses and pentax doesn't have a FF body neither in 35mm format nor in 645 format.
03-16-2011, 10:29 AM   #52
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QuoteOriginally posted by Spare Tire Quote
Same arguments apply: people who want to use the full image circle of their FF lenses also want to use the full image circle of their 645 lenses and pentax doesn't have a FF body neither in 35mm format nor in 645 format.

So what? Pentax doesn't make a digital rangefinder camera, either. If you want one of those, it doesn't mean that Pentax should build one. Just go buy a Leica M9.


Pentax has been very consistent about FF. The answer is "NO". If you want a FF dslr camera, buy a Nikon, Canon or Sony.

Personally, I believe that, given Pentax' finances and market position, launching a FF camera right now would be suicide. The FF market is a tiny fraction of the dslr market, and Nikon and Canon have that sewn up pretty tightly. Even Sony has barely made a dent in their share. And Sony has a lot more money to spend than does Pentax.

I think that it would be optimistic to think that Pentax could capture even five percent of the FF market. That means that there would be no economy of scale. Development costs that must be amortized per camera would be something like twenty times what C & N have to build into their prices.

Pentax does not have a good stable of FF-capable lenses. That would cost a fortune to develop and build.

Pentax seems to be doing much better than it was under the old management, prior to the Hoya buyout, but they are still not out of the woods. Hoya is being (rightly, IMHO) very conservative and trying to target their investments carefully.

I don't think that they would have green-lighted the 645D, if the old management had not already spent the development money. When Hoya came in, it was virtually ready to go into production. The only way that Hoya could recoup any of that development money was to actually build and sell the camera.

Plus, the 645D entered a significantly different market than would a FF camera. They were able to bring it in at a price that was very competitive. The dslr market, even the FF market is much harder for a small player like Pentax to compete in.

03-16-2011, 10:35 AM   #53
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QuoteOriginally posted by Spare Tire Quote
Same arguments apply: people who want to use the full image circle of their FF lenses also want to use the full image circle of their 645 lenses and pentax doesn't have a FF body neither in 35mm format nor in 645 format.
Yes, there's no end to this.
03-16-2011, 02:30 PM   #54
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QuoteOriginally posted by Spare Tire Quote
Same arguments apply: people who want to use the full image circle of their FF lenses also want to use the full image circle of their 645 lenses and pentax doesn't have a FF body neither in 35mm format nor in 645 format.

Oh boy....Lucy....let me splain something to you...!!
03-17-2011, 08:50 AM   #55
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I’m thinking, if Pentax made a medium format camera (645D), what is the rezone not to go for a 35mm sensor?
Some said that the market controlled by Canon-Nikon. So what?
How many are the buyers for 645D? The medium format market is that big?
Additionally, 645D is more expensive than a 35mm DSLR. So, why they hesitate?

In my opinion, Pentax, wants to stabilized in the market of ASP-C sensors and make a reputation. So from K20D, K-7 and especially with K-5 they managed to be equal, if not better, than the other brands.

I’m thinking also that when they get rid of some cropped sensors, they will produce a 35mm DSLR. As for the time, I’m guessing that, no longer than two years from now, will purchase a FF Pentax. The market will guide them to 35mm. There is no other choice.
03-17-2011, 10:09 AM   #56
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QuoteOriginally posted by yperion Quote
I’m thinking, if Pentax made a medium format camera (645D), what is the rezone not to go for a 35mm sensor?
Some said that the market controlled by Canon-Nikon. So what?
How many are the buyers for 645D? The medium format market is that big?
Additionally, 645D is more expensive than a 35mm DSLR. So, why they hesitate?
Scroll a few posts above for the answer:

QuoteOriginally posted by noblepa Quote
Pentax seems to be doing much better than it was under the old management, prior to the Hoya buyout, but they are still not out of the woods. Hoya is being (rightly, IMHO) very conservative and trying to target their investments carefully.

I don't think that they would have green-lighted the 645D, if the old management had not already spent the development money. When Hoya came in, it was virtually ready to go into production. The only way that Hoya could recoup any of that development money was to actually build and sell the camera.

Plus, the 645D entered a significantly different market than would a FF camera. They were able to bring it in at a price that was very competitive. The dslr market, even the FF market is much harder for a small player like Pentax to compete in.
And MF users seem to like the 645D:
Pentax 645D - A First Review

Canon FF doesn't look that good in the following comparison, but the Leica M9 holds its own:
2010 Mini Medium Format Shoot-out
03-17-2011, 10:21 AM   #57
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QuoteOriginally posted by Laurentiu Cristofor Quote
Scroll a few posts above for the answer:



And MF users seem to like the 645D:
Pentax 645D - A First Review
Of course part of this is because a FF medium format 645 is still in the 50K range. I imagine as the sensor costs come down we will see a FF 645D as well. it is a market where the cost will be recoupable.
Despite the constant no FF coming from Hoya/Pentax I believe there will come a time they have no choice. it will be driven by lower cost FF sensors. Once you see sub $200 FF on a newer camera from canikon it will drive the market. And Pentax has loads of FF lenses out there already and can easily do what they are doing with the 645 lenses and put older designs back into production, perhaps with some coating upgrades to fill the missing holes. Many of the DA lenses actually work on FF with the exception of the wide angle models
I would agree with the poster above this is likely in 2 years but may take 3 -4 for pentax to respond to the Market change that canon (likely) will drive
03-18-2011, 07:40 AM   #58
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I want a full frame large format digital. I'm thinking an 8x10 would do for my landscaping needs.
03-18-2011, 09:39 AM - 1 Like   #59
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QuoteOriginally posted by eddie1960 Quote
Despite the constant no FF coming from Hoya/Pentax I believe there will come a time they have no choice. it will be driven by lower cost FF sensors
Prima facie, that is a plausible argument, one which I would have been inclined to accept not so long ago. However, I think it fails to note that an FF camera, regardless of price, it's fairly useless without lenses; and here the very quality of the FF sensor demands high quality glass to go with it. After all, there wouldn't be much point in buying an FF camera and sticking a cheap kit lens in front of it. So it's not just the price of the FF sensors here that's important, but the price of the FF glass. First rate FF zoom glass, just the kind needed to draw every last ounce of IQ out of those wonderful FF sensors, costs north of $1,500, and soon, with the Japan quake, rising energy prices, and the falling dollar, even a first-rate FF normal prime is going to cost at least $500, and the wide angles and tele primes will cost even more. Worse, the prices on lenses is only going to go up, while the FF sensors can only go down to a certain point. Add to this the fact that the APS-C sensors are getting pretty good in their own right, and that many photo-enthusiasts have already invested in APS-C glass, and you don't have a particularly rosy scenario for a large scale (or even a medium scale) flight to FF. If APS-C DSLRs are threatened at all, it is from the mirrorless interchangable lens cameras nipping at its heels from below, rather than the FF DSLRs threatening from above.
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