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09-15-2013, 06:37 PM   #346
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QuoteOriginally posted by Rondec Quote
DXO Mark explains their measurements and Falk Lumo agrees with them. This is their comparison article at the time of the K5 sensor evaluation: DxOMark - DxOMark review for the Pentax K5


There are different ways to interpret and measure DR. DxOMark has what they call 'screen' and 'print' to name two. Bill Claff has been measuring something that tracks what you will actually see in practice quite closely, PDR, which account's for the sensor's CoC:

.


11-04-2013, 07:41 PM   #347
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QuoteOriginally posted by adwb Quote
So here we sit with a bag full of assorted lenses from old manual ones right through to hsm models and our apsc bodies, and I keep seeing forum members crying because there is no full frame on the Pentax line up.
Why?
What do they think they are going to get with a ff and their existing glass that they can't do now?

For how many would the change in DOF actually be the deciding factor or is there something else that I am missing here?
You get to take pictures using the normal size format in the digital SLR age.
You get the golden 2x3 ratio.
The full frame prism has enough room to fit in manual focus aids without affecting metering.
The larger the frame, the less harsh the contrast and other artifacts.
Digital format problems like chromatic aberration also get greatly reduced, and no, digital compensation doesn't really work.
Specks of dirt that gather on the sensor between cleanings appear as less humongous.
Who invented "digital size" format anyway?
11-04-2013, 08:24 PM   #348
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QuoteOriginally posted by niiicedave Quote
You get to take pictures using the normal size format in the digital SLR age.
You get the golden 2x3 ratio.
The full frame prism has enough room to fit in manual focus aids without affecting metering.
The larger the frame, the less harsh the contrast and other artifacts.
Digital format problems like chromatic aberration also get greatly reduced, and no, digital compensation doesn't really work.
Specks of dirt that gather on the sensor between cleanings appear as less humongous.
Who invented "digital size" format anyway?
There's nothing "normal" about the 24 x 36mm format, although it is a standard established through long use. The Golden Ratio is actually a bit wider at 2x3.22, which works out at around 24 x 39mm or 22 x 36, but bear in mind that we're talking about a ratio established empirically from architecture, which doesn't necessarily translate automatically into a visual frame.

People's experience with manual focus aids in the form of substitute viewfinder screens seems to vary, here. Some say certain ones do, while others disagree. I'm at a loss to understand why the screen size might affect that to the extent you describe, regardless.

CA is usually dealt with fairly readily and effectively by software solutions. Purple fringing can be more of an issue, and Moire even more so.

I assume by "digital size", you mean APS-C (as ill-defined as that is), in which case it was invented for film cameras, but had much less success there than in digital cameras, where its use was dictated by the prohibitive cost of a 24 x 36 sensor for all but the wealthy or professional photogrpaher. I dare say most manufacturers were put off for a while by the early collapse of Contax and the failed development of the original Pentax DSLR prototype, both of which used (or proposed to use, in Pentax's case) a 24 x 36 sensor.
11-06-2013, 09:01 AM   #349
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QuoteOriginally posted by adwb Quote
So here we sit with a bag full of assorted lenses from old manual ones right through to hsm models and our apsc bodies, and I keep seeing forum members crying because there is no full frame on the Pentax line up.
Why?
What do they think they are going to get with a ff and their existing glass that they can't do now?

For how many would the change in DOF actually be the deciding factor or is there something else that I am missing here?
'Holy Grail', full frame? I think it's as close as '35mm' digital SLR user's can get to perfection.
I think most K7/K5 users are quite happy with what they have, with respect to not upgrading to a K3 model; however Pentax Man (or woman) by their very nature still seek perfection.
Does cramming more pixels onto the K3 means more in camera processing and larger capacity memory cards? I think the answer maybe yes.
For me, it would have been logical to make room for a full frame sensor within the confines of the K3 Body and called it the K3FF. I personally have a range of prime Pentax and Tamron SP lenses (with PKA mounts fitted); I can get £40 for each mount, change them for AiS (for Nikon) and use my prize primes on a Nikon D700. I honestly think Pentax made a serious error of judgement in launching the K3 in it's present form.
Personally I would prefer 16 - 20 mega pixels in a full frame sensor. If anyone has a different point of view, that can persuade me to retain my allegiance to the Pentax brand I will follow this forum with interest.

11-06-2013, 09:08 AM   #350
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QuoteOriginally posted by adwb Quote
So here we sit with a bag full of assorted lenses from old manual ones right through to hsm models and our apsc bodies, and I keep seeing forum members crying because there is no full frame on the Pentax line up.
Why?
What do they think they are going to get with a ff and their existing glass that they can't do now?

For how many would the change in DOF actually be the deciding factor or is there something else that I am missing here?
I think most K7/K5 users are quite happy with what they have, with respect to not upgrading to a K3 model; however Pentax Man (or woman) by their very nature still seek perfection.
Does cramming more pixels onto the K3 means more in camera processing and larger capacity memory cards? I think the answer maybe yes.
For me, it would have been logical to make room for a full frame sensor within the confines of the K3 Body and called it the K3FF. I personally have a range of prime Pentax and Tamron SP lenses (with PKA mounts fitted); I can get £40 for each mount, change them for AiS (for Nikon) and use my prize primes on a Nikon D700. I honestly think Pentax made a serious error of judgement in launching the K3 in it's present form.
Personally I would prefer 16 - 20 mega pixels in a full frame sensor. If anyone has a different point of view, that can persuade me to retain my allegiance to the Pentax brand I will follow this forum with interest.
11-06-2013, 11:46 AM   #351
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QuoteOriginally posted by harryzero Quote
I think most K7/K5 users are quite happy with what they have, with respect to not upgrading to a K3 model; however Pentax Man (or woman) by their very nature still seek perfection.
Does cramming more pixels onto the K3 means more in camera processing and larger capacity memory cards? I think the answer maybe yes.
For me, it would have been logical to make room for a full frame sensor within the confines of the K3 Body and called it the K3FF. I personally have a range of prime Pentax and Tamron SP lenses (with PKA mounts fitted); I can get £40 for each mount, change them for AiS (for Nikon) and use my prize primes on a Nikon D700. I honestly think Pentax made a serious error of judgement in launching the K3 in it's present form.
Personally I would prefer 16 - 20 mega pixels in a full frame sensor. If anyone has a different point of view, that can persuade me to retain my allegiance to the Pentax brand I will follow this forum with interest.
I thoroughly agree with Harry. 24mp on FF would be about right I reckon.

I think all this is down to FF chip availability for Pentax. Sony aren't going to want to sell their new range of FF sensors to a competitor just yet. The A7r gives me hope it will be available at some point relatively soon though.
11-16-2013, 10:30 AM   #352
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QuoteOriginally posted by harryzero Quote
I think most K7/K5 users are quite happy with what they have, with respect to not upgrading to a K3 model; however Pentax Man (or woman) by their very nature still seek perfection.
Does cramming more pixels onto the K3 means more in camera processing and larger capacity memory cards? I think the answer maybe yes.
For me, it would have been logical to make room for a full frame sensor within the confines of the K3 Body and called it the K3FF. I personally have a range of prime Pentax and Tamron SP lenses (with PKA mounts fitted); I can get £40 for each mount, change them for AiS (for Nikon) and use my prize primes on a Nikon D700. I honestly think Pentax made a serious error of judgement in launching the K3 in it's present form.
Personally I would prefer 16 - 20 mega pixels in a full frame sensor. If anyone has a different point of view, that can persuade me to retain my allegiance to the Pentax brand I will follow this forum with interest.
why not 36MP for max detail if needed? also cropping can match APS-C senors at 24MP ..for me if I go FF its 36 or really not worth it

11-16-2013, 12:01 PM   #353
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QuoteOriginally posted by Shanti Quote
why not 36MP for max detail if needed? also cropping can match APS-C senors at 24MP ..for me if I go FF its 36 or really not worth it
Actually cropping a 36 megapixel image gives you a 16 megapixel APS-C image.
11-16-2013, 07:39 PM   #354
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QuoteOriginally posted by Rondec Quote
Actually cropping a 36 megapixel image gives you a 16 megapixel APS-C image.
too many MP... its like if I shoot my 300 on FF its the same as if I shoot on K5II as I can crop the FF & get the same results,almost..but for BIF maybe no difference
11-16-2013, 10:11 PM   #355
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QuoteOriginally posted by Shanti Quote
too many MP... its like if I shoot my 300 on FF its the same as if I shoot on K5II as I can crop the FF & get the same results,almost..but for BIF maybe no difference
BIF is easier in my experience... it's far easier to track with 'extra' space around the bird.
11-16-2013, 10:47 PM   #356
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QuoteOriginally posted by Rondec Quote
Actually cropping a 36 megapixel image gives you a 16 megapixel APS-C image.
And cropping the K3 gives a very usable 12mp file with even more reach...
11-17-2013, 07:01 AM   #357
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QuoteOriginally posted by ElJamoquio Quote
BIF is easier in my experience... it's far easier to track with 'extra' space around the bird.
+1
That's something not appreciated enough IMHO.

QuoteOriginally posted by Shanti Quote
why not 36MP for max detail if needed? also cropping can match APS-C senors at 24MP ..for me if I go FF its 36 or really not worth it
24MP cropped requires 56MP FF for same pixel density.

But "max detail" is far from that. I tried with a DA*300 on film vs. e.g., a 14MP K-7, using the same 4x minaturized ISO inset (0.25x scale) on my personal ISO test chart. Here is the comparative result:



(a 200% crop from a 14MP image, i.e., size shown would roughly compare to a 56MP camera (which would be sharper though); it is the sharpest I ever achieved with a K-7 (using DA 70 Ltd.))

vs. film:



Isn't is shocking how much more information film can grab than even 56MP digital ever could?

Obviously, above we see signs of lens softness with film grain able to resolve twice the lines, I guess. The roughness of edges is half film grain, half printer dots.

(Technical note: the avove is a microscope view for a Gigabit document film shot on a Pentax *ist film camera using AF and the DA* 300 IIRC -- the rings are the fine features of the test charts inner circle).

So, we aren't anywhere near "max. detail"

QuoteOriginally posted by Rondec Quote
Actually cropping a 36 megapixel image gives you a 16 megapixel APS-C image.
Correct.
11-17-2013, 10:45 AM   #358
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Falconeye,

You're about the smartest person I've ever witnessed. Please can you make me a full frame camera which has in-body VR or SR, can handle high ISO noise like the Hubble telescope and has a short flange distance so I can adapt any old lens? Manual focus will do but accurate AF adapters would be great because I'm quite lazy to be frank.

I really, really want one.

Tonight was Loi Krathong here in Thailand and although the K-5 IIs did fairly well, the best shots came from manual focus using the K 50mm f/1.2 at ISO 1600 or below. I just wish I had a FF camera to mount the thing on! Beyond ISO 1600 the output was pretty bad and at ISO 3200 virtually untameable using LR 5.2.



Loi Krathong - a set on Flickr
11-17-2013, 10:55 AM   #359
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I'd rather have a vario-pull out LCD screen. Anyone with me??
C'mon.. you know you'd like that.
11-17-2013, 11:01 AM   #360
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QuoteOriginally posted by Parry Quote
high ISO noise like the Hubble telescope
I am sorry to say, but I fear Hubble doesn't have that good of a high iso performance. I heard they are using incredibly long exposure times and an amazingly wide aperture diameter to cope with that.

Before I go to my drawing board to make your dream camera, please assure you can hand-hold a 1 ton camera for, say, 2 hours steadily without the smallest shake
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