Forgot Password
Pentax Camera Forums Home
 

Reply
Show Printable Version Search this Thread
03-20-2016, 07:59 AM   #286
Pentaxian




Join Date: Jun 2009
Location: GMT +10
Photos: Albums
Posts: 10,832
QuoteOriginally posted by ACG Quote
I have done comparisons between sony a7r (36mp) with pentax k28 and sony Rx100 mk3 (20 MP 1 inch sensor) at A2 and can"t spot any significant difference
+1 for that. The RX-100 can often produce very impressive results. It provides a useful perspective on how silly camera sensor size arguments can be sometimes.

03-20-2016, 08:17 AM - 2 Likes   #287
Senior Moderator
Loyal Site Supporter
Parallax's Avatar

Join Date: Apr 2008
Location: South Dakota
Photos: Gallery
Posts: 15,614
QuoteOriginally posted by jsherman999 Quote
Selectively quoting again? Why don't you quote some things from this thread, in which your... EDIT "interesting"... theories were not-so-gently shown the door (big D is the 'unknown member' in that thread, becuase he was later banned as a troll.) Link to major fail

.
He won't be quoting anything here for awhile.
03-20-2016, 08:19 AM - 3 Likes   #288
Veteran Member
jsherman999's Avatar

Join Date: Dec 2007
Photos: Gallery
Posts: 8,228
QuoteOriginally posted by rawr Quote
+1 for that. The RX-100 can often produce very impressive results. It provides a useful perspective on how silly camera sensor size arguments can be sometimes.
My current Fav Nat Geo shot was taken with an RX-100:



Don't know what PP went into that, but one thing that strikes me is that there's 'enough' DR to make the image work. RX-100 did a great job. Photographer did a one-in-a-million job.


.
03-20-2016, 08:30 AM   #289
Veteran Member
Tan68's Avatar

Join Date: Sep 2014
Photos: Albums
Posts: 396
QuoteOriginally posted by dtmateojr Quote
...
See, this is why I didn't want to answer your question because it is so obvious! Of course 16Mp is the same IMAGE SIZE as any other 16Mp REGARDLESS of sensor size. But, dude, they are NOT the same resolution. A 16Mp APS-C or m43 has MORE resolving power than a 16Mp FF sensor.

See if you can figure that out...
Each pixel of the APS-C sensor will be smaller than each pixel of the FF sensor. In a sense, this means the APS-C sensor has greater resolution. It is some the same as looking a ruler with graduations in mm (APS-C) rather than a ruler with graduations in cm only (FF).

However, projection size does matter.
The example scene will be of a Volkswagen car with proper emission controls.

The magnification of the VW will be the same in both images; the front bumper will be aligned with the left edge of both sensors and the rear bumper will be aligned with the right edge of both sensors. So, the size of the door handles will look the same in both finished images. For the door handles to be the same apparent size in both images, some rules of equivalency will be followed (and why to follow the rules will be below).

Alright, standing in the same spot for both exposures, the image taken with the FF will be by using a 43mm lens and the image taken with the APS-C will be by using a 28mm lens. In both cases, the VW will be projected onto the sensor in the same way (not exactly, but pretend so, for the sake of argument). The door handles will be the same relative size on each sensor. If the door handle is .08% surface area of the FF sensor, it will be .08% surface area of the APS-C sensor. The door handle will cover the same number of pixels in both the image projected on the FF sensor and the image projected on the APS-C sensor.

The resolution with respect to that door handle will be the same in both images...

Of course, if we had used the 43mm on the APS-C camera, the VW would be projected larger on the sensor. The door handles would cover a greater surface area of the sensor, they would cover more pixels, and those door handles would be displayed in greater resolution. However, to cover that bet and raise you, I could go hunt a.. 65mm lens for the FF. The lens doesn't exist so I would keep the 43mm on the FF and just step just closer to the car so that the same parts of the car are framed and projected onto my FF sensor as they were on the APS-C sensor.

The reason an element of equivalency, field of view, is important is because I have a picture in mind. I want a picture of the car bumper to bumper. The picture is for Better Homes & Garden magazine and I have no choice :^| So, whatever lens combo I choose between the FF and APS-C, I will have to photograph bumper to bumper.. I can choose different lenses that offer the same field of view on the differently sized sensors or I can use the same lens and walk either toward or away from the car.

With either choice above, I end up with the projection of the VW just covering either sensor so the number of pixels covered by those door handles will be the same... This consideration of projection size also helps explain an argument made by some people that smaller sensors are more demanding of lens resolution, but that discussion is a tangent.

Respect to field of view is important to me when considering FF. I look at the pictures I have taken of stuff in cathedrals. I have a picture of a silver bull with wings taken with APS-C and 77mm lens and it is framed nicely.. When I use the 77mm lens on a FF, I know the field of view will be wider. I know I will want the bull to be framed just the same because I am not going to be satisfied with a smaller flying bull. So, I will have to either get closer to the bull or I will have to buy a 105mm lens. This is where practical considerations of equivalency come into play: considering what is required to record the image you have in mind.

Rather than step closer to my angelic bull or mount the 105mm, I could crop the FF image. If both the APS-C and FF sensors have 16 MP then, yes, the image produced with the APS-C will have more resolution. But this doesn't mean equivalency is a bull with no wings. Besides, the K-1 has 36 MP so I can crop it to equal field of view equal to the same lens on an APS-C and be close enough to 16 MP...

This digital zoom (crop mode of FF) is a reason I am interested in K-1. I will have an option of wider fiend of view with the 77 on the K-1 or I can use 'crop mode' to enjoy the 'longer reach' the 77 gave me on K5. In a way, I will have two lenses in one. Because I am happy with K5 performance, I will not mind sometimes using K-1 crop mode to take advantage of my 'virtual' lens.

Anyway, I think my post wandered a bit at the end. I admit a 16 MP APS-C sensor has smaller pixels than a FF sensor. The graduations on the APS-C ruler are smaller than on the FF ruler. But that doesn't mean an APS-C has more resolution than FF when it comes to subject, composition, and projection size.

Looking at absolute resolution irrespective of composition is no longer photography.

++ Looking at posts subsequent to the one I quoted, I think it is possible there may be a divide across the digital Minnelli. Projection size may be a difficult concept if people have not seen either a slide go into a projector or a negative go into an enlarger... Comparing these things to a digital projector hooked up to an iPhone does not help... there is no constant physical size associated with the iPhone+projector as there is with either the slide projector or film enlarger or image sensor size.

I begin to understand the arguments that a cell phone camera is all any person needs.. after all, why stop the train of thought at either the 4/3 or APS-C stations...


---------- Post added 03-20-16 at 10:32 AM ----------

QuoteOriginally posted by jsherman999 Quote
... Photographer did a one-in-a-million job.


.
The photo could also be used for training: There are two divers on the right and three coral crunching moon walkers on the left.

+ ...the greater resolution of the smaller sensor allows me to see there are actually more than three coral crunchers out there. The whale is surrounded by moon walkers. Guess which few lead the dive :^)


Last edited by Tan68; 03-20-2016 at 08:56 AM.
03-20-2016, 11:02 AM - 1 Like   #290
Pentaxian




Join Date: Nov 2014
Location: South Bend, IN, USA
Photos: Gallery | Albums
Posts: 2,982
QuoteOriginally posted by dtmateojr Quote
OMG?! ROFL!!!

See, this is why I didn't want to answer your question because it is so obvious! Of course 16Mp is the same IMAGE SIZE as any other 16Mp REGARDLESS of sensor size. But, dude, they are NOT the same resolution. A 16Mp APS-C or m43 has MORE resolving power than a 16Mp FF sensor.
A sensor does not have resolving power; it uses resolving power. If I fill a 16MP frame with a railroad locomotive, the number of pixels dedicated to the small lettering on the cab will be exactly the same whether that frame is a medium format frame, a "full" frame, an APS-C frame, or a 1/1.7" frame; in the case of a smaller sensor, the lens will have to work harder to separate out the various components, but all the sensor does is to record what it receives, and if the lens managed to do the job, then {as mentioned above} the images will be exactly the same - no extra resolution to the credit of the smaller sensor. If this were not true, I wouldn't be the only one occasionally taking pictures of railroad equipment with a "Q".

Last edited by reh321; 03-20-2016 at 09:36 PM.
03-20-2016, 08:55 PM   #291
Senior Member




Join Date: Jan 2007
Location: Calgary, AB CA
Photos: Gallery
Posts: 292
36 mp > 16 mp.

Anything else is gravy; real, perceived, or mythical.

And when I get my preordered K-1, I've got a ton of lenses just waiting to test - for giggles.

Last edited by Ash; 03-21-2016 at 06:27 PM.
03-20-2016, 09:50 PM   #292
Pentaxian




Join Date: May 2009
Location: Ponoka Alberta Canada
Photos: Gallery
Posts: 545
QuoteOriginally posted by dtmateojr Quote
What?!!! Your calculations for IMAGE size was not image size. You were calculating for SENSOR size (sensel pitch x num of pixels). Duh?! Sensor size is NOT equal to image size. Fact.
There is only one image size that can be measured, the one projected by the lens everything else is scaled off of that image.
QuoteOriginally posted by dtmateojr Quote
I NEVER said that. I never mentioned total light. You equivalence fu proponents should stop using that total light crap.
I added total light in brackets as that is what the signal is made of minus read noise.
QuoteOriginally posted by dtmateojr Quote
I said K5 and D800 have same SNR and dxomark SCREEN snr is PROOF of that.
and that screen snr shows that the d800 captured more signal by showing that the d800 can sample at a higher resolution while maintaining that snr of the single photo site
QuoteOriginally posted by dtmateojr Quote
FFS, I never said they capture the same total light. Learn to read.
I didn't ask you if the captured the same total light I asked "how can both signals have equal strength" so you wont get tripped up on total light
03-21-2016, 10:07 AM   #293
Junior Member




Join Date: Mar 2016
Posts: 40
Full frame cameras have better viewfinders, and I wish they'd make something like
the Nikon F3HP or Contax Aria regarding eye relief.
The percentage of people who really 'need' full frame quality resolution is probably very small.
Yes the dynamic range of FF is great, but trounced by 645D.
What percentage of shooters ever make big prints...I don't and the only ones I have made were
with MF film in my own darkroom. So, for me buying into top spec digitalia is a bit meaningless.

I like the K1 sensor shift function, it's actually something I talked about 8 years ago,
pity they didn't make it tilt as well, would be super cool.

- Waiting for my new K3ii to arrive.

03-21-2016, 01:30 PM   #294
Pentaxian
cali92rs's Avatar

Join Date: May 2011
Location: Long Beach, CA
Posts: 3,346
QuoteOriginally posted by BenCPentax Quote

Yes the dynamic range of FF is great, but trounced by 645D.
If by trounce you mean has LESS dynamic range, then yes.
The D810 has 14.8 EVs of dynamic range at Base ISO and the 645D has a dynamic range of 12.6 EV.

Unfortunately, the 645Z has not been tested, but I would be willing to bet the difference in DR between the 645Z and the D810 (or K-1) is less than the difference between the D810 (or K-1) and your K-3II.
03-21-2016, 01:49 PM   #295
Pentaxian
Pål Jensen's Avatar

Join Date: Dec 2007
Location: Norway
Photos: Albums
Posts: 3,146
Insisting on having the same image quality from an FF camera as an APS body is missing the point entirely.

In principle it is no different from buying a 645z for getting same image quality as a cell phone, just a bit less silly.
03-21-2016, 02:03 PM   #296
Junior Member




Join Date: Mar 2016
Posts: 40
If as you say the K1 has better dynamic range than the K3ii (due to larger sensor and pixel size)
then it would follow that the larger sensor in the 645D would beat the dynamic range of the K1.

I wouldn't bet on a camera that hasn't been tested but I'd go for the Pentax 645D if I could.
03-21-2016, 05:16 PM   #297
Veteran Member
jsherman999's Avatar

Join Date: Dec 2007
Photos: Gallery
Posts: 8,228
QuoteQuote:
then it would follow that the larger sensor in the 645D would beat the dynamic range of the K1.
.
645Z would (probably,) but 645D is a much older CCD sensor. It's giving up some or most of it's 'larger' advantage because of that.

Last edited by jsherman999; 03-21-2016 at 05:35 PM.
03-21-2016, 05:44 PM - 1 Like   #298
Moderator
Loyal Site Supporter
BigMackCam's Avatar

Join Date: Mar 2010
Location: North East of England
Posts: 6,650
QuoteOriginally posted by BenCPentax Quote
If as you say the K1 has better dynamic range than the K3ii (due to larger sensor and pixel size)
then it would follow that the larger sensor in the 645D would beat the dynamic range of the K1.

I wouldn't bet on a camera that hasn't been tested but I'd go for the Pentax 645D if I could.
The 645D, whilst an excellent camera by all accounts, is quite old by now - sensor technology has come a long way since it was released. DXO shows the 645D's maximum dynamic range to be 12.6 EV, versus the APS-C sensor K-3's 13.4 EV... and as the ISO rises from base, the 645D's dynamic range will undoubtedly suffer quicker than the K-3. The K-1 will perform even better than the K-3, so...
03-21-2016, 06:27 PM   #299
Site Supporter




Join Date: Mar 2009
Location: Gladys, Virginia
Photos: Gallery
Posts: 16,230
QuoteOriginally posted by cali92rs Quote
If by trounce you mean has LESS dynamic range, then yes.
The D810 has 14.8 EVs of dynamic range at Base ISO and the 645D has a dynamic range of 12.6 EV.

Unfortunately, the 645Z has not been tested, but I would be willing to bet the difference in DR between the 645Z and the D810 (or K-1) is less than the difference between the D810 (or K-1) and your K-3II.
The 645Z has been tested, it is just that the results that haven't been released. D810 does have better dynamic range at base iso, but less dynamic range at the same iso (base for the 645z is 100). DXO Mark briefly released the data and then scrubbed it from their site.
03-21-2016, 07:48 PM   #300
Site Supporter
GeneV's Avatar

Join Date: Oct 2008
Location: Albuquerque NM
Photos: Albums
Posts: 9,775
QuoteOriginally posted by Rondec Quote
I think we are heading for this thread being shut down for good soon. Oh, well...

I guess I would say that I don't really understand the angst over this whole thing. Clearly at many print sizes (not all) a 36 megapixel sensor is going to produce significantly better results than a 16 megapixel APS-C sensor. And yes, if you have a larger sensor, your high iso performance does improve -- as long as you maintain a given print size.

I am planning to get a full frame camera. There will be some improvement in performance. My lenses will see a wider angle of view. I'll have to stop down a little to get more depth of field. But the end result (hopefully) will be nice images that I can share with others. Images of kids and family and landscapes. And honestly, all of these cameras are capable of taking nice images of those things in most settings. Even entry level cameras have nice image quality and amazing specs.

I am glad that Pentax is releasing a full frame camera and while I'll get one, I imagine my images will look pretty similar between the two, since the big factor is sitting about six inches behind the viewfinder.
Pretty much where I am. I have used my Pentax FF lenses on a Sony 36mp FF sensor for some time now. The main difference from 36mp for most of what I do is that it takes longer to process in PS and I can use a somewhat higher ISO. It is not changing all that much about my photography, but it is fun on some occasions. I'll be happy to use it with the reasonably priced K1 without an adapter.
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, 300mm, advantages, app, aps-c, body, camera, cost, crop, dslr, f/2.8, ff, field, focus, frame, full-frame, k-1, k-3, k3, lens, ovf, pentax, pentax k-3, quality, sensor, sigma, view
Thread Tools Search this Thread
Search this Thread:

Advanced Search


Similar Threads
Thread Thread Starter Forum Replies Last Post
Crop Sensors vs Full Frame :: Crop Or Crap? i83N Photographic Industry and Professionals 44 07-30-2014 06:00 AM
No Pentax Full Frame DSLR, What to Do Now Then? RiceHigh Pentax DSLR Discussion 95 07-19-2014 10:57 AM
The Full Frame NEX is going to be announced in October ! jogiba Non-Pentax Cameras: Canon, Nikon, etc. 30 09-15-2013 03:23 PM
So.... Pentax Full Frame is a sure thing? LFLee Photographic Industry and Professionals 25 11-02-2012 12:55 PM
So It's True....a Full-Frame 'Professional' Samsung Dslr Coming !!!! Confused Pentax DSLR Discussion 9 05-02-2008 04:12 PM



All times are GMT -7. The time now is 03:24 PM. | 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