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08-11-2014, 02:38 PM   #661
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QuoteOriginally posted by Mistral75 Quote
Oh, Teledyne Dalsa's 80Mpix 40.4x53.7mm CCD sensor isn't bad either .
The difference between that and 645D size is more than the difference between 645D and FF...

... that would be nice... make some fast glass out of the 645 system.

08-11-2014, 03:38 PM   #662
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QuoteOriginally posted by ElJamoquio Quote
Tt seems like 36x24mm is too close to 44x33 though. Here's hoping a 'reasonably priced' 56x41mm is
I hope you understand that the 44x33 is almost double the area of the 36x24. The difference in not close at all in silicon production
08-11-2014, 04:34 PM   #663
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QuoteOriginally posted by bobmaxja Quote
I hope you understand that the 44x33 is almost double the area of the 36x24. The difference in not close at all in silicon production
I'm well aware, the 44x33 is 70% larger. I'm aware of defect rates etc.

That said I was speaking in terms of output of the sensor. The 44x33 will be sharper than a 36x24, but it's only about 2/3rds of the difference between APSC and FF. I hope that, in order to increase the drive to better cameras, they put out bigger sensors. Still worse yield, of course, but it makes getting fast glass easier. Right now the fastest-equivalent-glass that Pentax has is actually, by a hair, still K-3, rather than 645Z.
08-11-2014, 04:44 PM   #664
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Faster glass does not get easier to get with larger formats and in fact impossible to get with really large formats. Ie theres is no1.4 lens for MF.
Lens speed has nothing to do with DOF or format size by definition. Lens speed/aperture is by definition intertwined with exposure. The word speed reflect to the fact that you can shoot at a faster shutter speed; it does not involve DOF in its definition.
Neither the definitions of lens speed, focal lenght or format involves DOF.
A certain lens has the same speed regardelss of what format you are using it on (eg the SMC Pentax 67 75/2.8 that can be used on five different formats). In other words, the same aperture is the same speed cross formats.


Last edited by Pål Jensen; 08-11-2014 at 04:55 PM.
08-11-2014, 10:56 PM   #665
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Thanks for the clarifications regarding the medium format rumors for other brands. It seems they have their own unicorns too... lol. I clearly haven't been around enough (or lurking enough in the web) to see that these rumors have been floating for a long time.

But the case remains the same: Can we hope that Ricoh/Pentax can make a good impression for this year's Photokina?

If there's any announcement I'd like to hear from Ricoh Imaging, it's that they are strengthening their after-sales and professional system support. The cameras are already good- a few software tweaks can make them even better, but what we all need is better market presence, physically (e.g. stocks in stores) and spreading good news without having to resort to "letting the users do the marketing talk"

...and oh yeah new lenses wouldn't hurt
08-12-2014, 12:47 AM   #666
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QuoteOriginally posted by Mistral75 Quote
Oh, Teledyne Dalsa's 80Mpix 40.4x53.7mm CCD sensor isn't bad either .
Of course but it is CCD and hence, even more a specialty item now that Sony's coming. That's why they need to open up to other customers IMO.
08-12-2014, 07:51 AM - 1 Like   #667
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QuoteOriginally posted by dcshooter Quote
The Canon MF rumor has been floating around since last Photokina, and if I recall, it was revealed to be a hoax pretty quickly.

From 2012:
Canon Medium Format DSLR and Sony NEX-6 Both Coming Next Month?

And here, the same guy spreading the same rumor in 2013:
Rumor: Canon Hopes to Launch a Digital Medium Format System in 2014
And apparently it was done back in 2010 as well:
Canon release MEDIUM FORMAT CAMERA! (april fools joke) - Canon Digital Photography Forums


The black box with the Canon logo completely out of perspective with the rest of the image as well as an image of the original Mamiya camera only elicits a "probably?"

Yes terrible. They also do that same joke about a Full Frame Pentax every Photokina.............................

08-12-2014, 08:03 AM   #668
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Here's what I think of unicorns:



08-12-2014, 08:38 AM   #669
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Isn't eating unicorns against the law, or something?
08-12-2014, 08:42 AM   #670
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QuoteOriginally posted by Cynog Ap Brychan Quote
Isn't eating unicorns against the law, or something?
Hogwarts = secret unicorn abattoir.
08-12-2014, 09:18 AM   #671
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QuoteOriginally posted by Pål Jensen Quote
Faster glass does not get easier to get with larger formats and in fact impossible to get with really large formats. Ie theres is no1.4 lens for MF.
Lens speed has nothing to do with DOF or format size by definition. Lens speed/aperture is by definition intertwined with exposure. The word speed reflect to the fact that you can shoot at a faster shutter speed; it does not involve DOF in its definition.
Neither the definitions of lens speed, focal lenght or format involves DOF.
A certain lens has the same speed regardelss of what format you are using it on (eg the SMC Pentax 67 75/2.8 that can be used on five different formats). In other words, the same aperture is the same speed cross formats.
Hmm. I even put fastest EQUIVALENT glass in the text, and I still get the same reply. 'Speed' refers to the faster shutter speed. We both know this.

Since you have higher IQ with larger formats, you can shoot at the same SPEED with the same image quality when the larger format is at a higher ISO.

You might not like equivalence, Pal, but I think you should get used to other people considering it a useful tool.

---------- Post added 08-12-14 at 09:19 AM ----------

QuoteOriginally posted by Cynog Ap Brychan Quote
Isn't eating unicorns against the law, or something?
You're thinking of Cows.
08-12-2014, 11:06 AM   #672
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QuoteOriginally posted by ElJamoquio Quote
Hmm. I even put fastest EQUIVALENT glass in the text, and I still get the same reply. 'Speed' refers to the faster shutter speed. We both know this.

Since you have higher IQ with larger formats, you can shoot at the same SPEED with the same image quality when the larger format is at a higher ISO.

You might not like equivalence, Pal, but I think you should get used to other people considering it a useful tool.
Yes that typically you hand up doing if you need the dof and there is not much light:

You stop down to get some dof, bump the isos accordingly to maintain some speed and get the same quality as the smaller format that could use a wider apperture and lower iso.

In other terms, the higher iso performance is only relevant on larger format if the smaller format equivalent apperture can't be selected on that format lenses gear.
08-12-2014, 05:31 PM   #673
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QuoteOriginally posted by Pål Jensen Quote
Lens speed has nothing to do with DOF or format size by definition.
Please visit a DOF calculator and change the "lens speed" and see what it does to the DOF.

If you use a DOF calculator that allows you to choose the format size, you'll see that the latter influences DOF as well.

QuoteOriginally posted by Pål Jensen Quote
The word speed reflect to the fact that you can shoot at a faster shutter speed; it does not involve DOF in its definition.
"Lens speed" is photographer slang and references the fact that a brighter lens allows faster shutter speeds (while maintaining the same exposure).

A brighter lens (one that is brighter than others due to a larger aperture, not through a better t-stop) necessarily also has less DOF. The additional light adds more blur to out of focus areas. This is simply optics. Take it to the other extreme and consider the "slowest" (darkest) "lens" possible: A pinhole. The smaller the hole, the more DOF approaches infinity. Exposure and DOF are intrinsically linked.

QuoteOriginally posted by Nicolas06 Quote
In other terms, the higher iso performance is only relevant on larger format if the smaller format equivalent apperture can't be selected on that format lenses gear.
That's exactly right.

That's why FF does not really have a "low light advantage". It offers a wider lens selection (including "faster" ones that help in low light by trading in DOF). FF natively supports higher dynamic range (assuming the same sensor technology) though; an advantage that is often not considered in comparisons (higher dynamic range can translate into less shadow noise).
08-13-2014, 05:25 AM   #674
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QuoteOriginally posted by Class A Quote
Please visit a DOF calculator and change the "lens speed" and see what it does to the DOF. .
I said that DOF is not involved in the definition of lens speed (or aperture) at all; not that DOF is independent on aperture (DOF is dependent on aperture, focal lenght, focusing distance and subject magnification). A fast lens is equally fast regardless of format you use it on. You don't get faster lens by going larger in format and if you go large enough there are no fast lenses at all due to cost/weight issues. Lens speed is tied to exposure by definition, not DOF.
One need to have a clear grasp of the definitions of aperture, lens speed, focal lenght, angle of view and DOF or else the discussion becomes meaningless.

---------- Post added 08-13-14 at 02:38 PM ----------

QuoteOriginally posted by ElJamoquio Quote
Hmm. I even put fastest EQUIVALENT glass in the text, and I still get the same reply. 'Speed' refers to the faster shutter speed. We both know this.

Since you have higher IQ with larger formats, you can shoot at the same SPEED with the same image quality when the larger format is at a higher ISO.

You might not like equivalence, Pal, but I think you should get used to other people considering it a useful tool.[COLOR="Silver"]
You mean thinner DOF. This is not the same as equivalent speed. Equivalent speed gives equivalent exposure by definition. Equivalent DOF do not.
"Equivalency" compensate rigidly this reduction in light by boosting the ISO correspondingly. However, no photographer respond to light reduction by boosting ISO exclusively. Hence, it is no law but an option.
In addition, the "same DOF" argument is only partly true as far as similar images are concerned. It is only so at certain focusing distances. Formats are simply not DOF equivalent. Note that smaller formats have higher magnification (with comparable lenses). Magnification is one of the factors that define DOF.

Last edited by Pål Jensen; 08-13-2014 at 05:49 AM.
08-13-2014, 05:41 AM   #675
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QuoteOriginally posted by Pål Jensen Quote
You don't get faster lens by going larger in format.
If the lens supports the larger format, it effectively collects more light (at the same f-stop).

You can claim that the lens does not become "faster" because the exposure stays the same but I maintain that this is using unhelpful terminology. The relevant factor for IQ is the total amount of light, which increases with larger formats.

Are you really claiming that "f/4" on FF is the same as "f/4" on a Q? That both lenses are equally "fast"? They are in terms of exposure but what good is the exposure corresponding to "f/4" on a Q? About as good as "f/22" on FF, so very "slow" (as in "not bright") and noisy in low light and lots of depth of field.
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