Forgot Password
Pentax Camera Forums Home
 

Reply
Show Printable Version Search this Thread
09-15-2013, 06:37 PM   #346
Veteran Member
jsherman999's Avatar

Join Date: Dec 2007
Photos: Gallery
Posts: 8,228
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
New Member




Join Date: May 2011
Location: United States
Posts: 7
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
Pentaxian
RobA_Oz's Avatar

Join Date: Nov 2008
Location: Tasmania, Australia
Photos: Gallery
Posts: 4,334
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
New Member




Join Date: Nov 2013
Posts: 9
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
New Member




Join Date: Nov 2013
Posts: 9
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
Veteran Member
Parry's Avatar

Join Date: Feb 2013
Posts: 541
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
Site Supporter
Shanti's Avatar

Join Date: Jul 2012
Location: Western Denmark
Photos: Gallery | Albums
Posts: 904
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
Site Supporter




Join Date: Mar 2009
Location: Gladys, Virginia
Photos: Gallery
Posts: 16,253
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
Site Supporter
Shanti's Avatar

Join Date: Jul 2012
Location: Western Denmark
Photos: Gallery | Albums
Posts: 904
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
Veteran Member




Join Date: Feb 2011
Posts: 4,893
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
Pentaxian




Join Date: Oct 2009
Location: North
Photos: Gallery
Posts: 3,921
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
Veteran Member
falconeye's Avatar

Join Date: Jan 2008
Location: Munich, Alps, Germany
Photos: Gallery
Posts: 6,863
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
Veteran Member
Parry's Avatar

Join Date: Feb 2013
Posts: 541
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
Senior Member
Iksobarg's Avatar

Join Date: Feb 2012
Posts: 208
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
Veteran Member
falconeye's Avatar

Join Date: Jan 2008
Location: Munich, Alps, Germany
Photos: Gallery
Posts: 6,863

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
Reply

Bookmarks
  • Submit Thread to Facebook Facebook
  • Submit Thread to Twitter Twitter
  • Submit Thread to Digg Digg
Tags - Make this thread easier to find by adding keywords to it!
24x36mm, aps-c, benefit, depth, ff, field, filter, frame, frame pentax, fuji, full-frame, goldilocks, iq, iso, noise, pentax, picture, resolution, sensor, terms
Thread Tools Search this Thread
Search this Thread:

Advanced Search


Similar Threads
Thread Thread Starter Forum Replies Last Post
So.... Pentax Full Frame is a sure thing? LFLee Photographic Industry and Professionals 25 11-02-2012 12:55 PM
Why is the K7 so terrible? or rather why am i having such a problem with it? runslikeapenguin Pentax DSLR Discussion 60 05-01-2012 01:16 PM
Why do people want a Full Frame sensor? RobG Pentax DSLR Discussion 98 02-15-2012 09:12 AM
Is there such a thing as a decent superzoom (for Pentax)? DanielT74 Pentax SLR Lens Discussion 22 06-21-2011 05:57 AM
Full-Frame Image Sensor Holy Grail - Why? stewart_photo Pentax DSLR Discussion 82 10-10-2007 03:00 AM



All times are GMT -7. The time now is 07:12 AM. | See also: NikonForums.com, CanonForums.com part of our network of photo forums!
  • Red (Default)
  • Green
  • Gray
  • Dark
  • Dark Yellow
  • Dark Blue
  • Old Red
  • Old Green
  • Old Gray
  • Dial-Up Style
Hello! It's great to see you back on the forum! Have you considered joining the community?
register
Creating a FREE ACCOUNT takes under a minute, removes ads, and lets you post! [Dismiss]
Top