Forgot Password
Pentax Camera Forums Home
 

Reply
Show Printable Version Search this Thread
06-18-2018, 06:56 PM   #1
Site Supporter
Site Supporter




Join Date: Dec 2008
Location: Eugene, Oregon
Photos: Albums
Posts: 57
Difference in quality between 'full-frame' and C sensor images.

I fully understand why a 36 x 24 negative, all things being equal, will yield a superior print to that from a 24 x 18 neg. The reason, in a word, is grain. But I do not understand digital photography well enough to understand how, exactly, the larger sensor yields a better result. It ain't grain! What I am trying to figure out is this:
Lets say the difference in maximum quality between 36 x 24 and 24 x 18 negatives is 10 compared with 6. If full-frame digital is a 10, how do C-sensor images compare? 6? 7? 5?

Thank you for taking the time to read my question.

btw...I still have my Pentax LX. It is MUCH smaller than my K3, so comparing full-frame with full-frame, the K1 is ginormous.

06-18-2018, 07:07 PM - 2 Likes   #2
Administrator
Site Webmaster
Adam's Avatar

Join Date: Sep 2006
Location: Arizona
Photos: Gallery | Albums
Posts: 47,545
QuoteOriginally posted by 3party Quote
I fully understand why a 36 x 24 negative, all things being equal, will yield a superior print to that from a 24 x 18 neg. The reason, in a word, is grain. But I do not understand digital photography well enough to understand how, exactly, the larger sensor yields a better result. It ain't grain! What I am trying to figure out is this:
Lets say the difference in maximum quality between 36 x 24 and 24 x 18 negatives is 10 compared with 6. If full-frame digital is a 10, how do C-sensor images compare? 6? 7? 5?

Thank you for taking the time to read my question.

btw...I still have my Pentax LX. It is MUCH smaller than my K3, so comparing full-frame with full-frame, the K1 is ginormous.
It's the same idea, except grain gets replaced by pixel pitch. A bigger sensor means bigger pixel pitch (=less noise/better color) or more pixels without sacrificing pixel pitch (=higher resolution) compared to a smaller sensor.

Here's a hands-on example and explanation:
How & Why Sensor Size Affects Image Quality (APS-C vs FF vs compact) - PentaxForums.com

Adam
PentaxForums.com Webmaster (Site Usage Guide | Site Help | My Photography)



PentaxForums.com server and development costs are user-supported. You can help cover these costs by donating. Or, buy your photo gear from our affiliates, Adorama, B&H Photo, or Topaz Labs, and get FREE Marketplace access - click here to see how! Trusted Pentax retailers:

06-18-2018, 07:13 PM - 1 Like   #3
Pentaxian




Join Date: Feb 2010
Location: Eureka, CA
Photos: Gallery | Albums
Posts: 2,693
You can't put a number on the difference between full-frame and APS-C. Full-frame is "better." How much better is largely subjective. Some people find the difference quite dramatic. Others not so much. I'm in the latter group. While I recognize the superiority of FF to APS-C, in actual practice, I don't see much difference. I go twice a month to a photo critique held by the local camera club. I see all kinds of photos, printed anywhere from 14 to 20 inches in size. At that size, you can't tell what kind of camera shot the pics. At that size, we've been fooled by iphone photos. At larger print sizes, all other things being equal, FF has an advantage — though perhaps not as big an advantage as some imagine. There's also an ISO and narrow DOF advantage with FF that some people find decisive to their photography.
06-18-2018, 08:25 PM   #4
Pentaxian




Join Date: Apr 2007
Location: Oklahoma USA
Posts: 1,597
QuoteOriginally posted by 3party Quote
I fully understand why a 36 x 24 negative, all things being equal, will yield a superior print to that from a 24 x 18 neg. The reason, in a word, is grain. But I do not understand digital photography well enough to understand how, exactly, the larger sensor yields a better result. It ain't grain! What I am trying to figure out is this:
Lets say the difference in maximum quality between 36 x 24 and 24 x 18 negatives is 10 compared with 6. If full-frame digital is a 10, how do C-sensor images compare? 6? 7? 5?

Thank you for taking the time to read my question.

btw...I still have my Pentax LX. It is MUCH smaller than my K3, so comparing full-frame with full-frame, the K1 is ginormous.
I think the difference is still "grain" in the sense of noise, plus sharpness, plus depth of field. Comparisons are model-depended, though - for example if you compare a higher pixel count APS vs. a lower pixel count full frame, that's a complicated comparison.

06-18-2018, 08:54 PM   #5
Pentaxian
Fogel70's Avatar

Join Date: Sep 2009
Location: Stockholm, Sweden
Photos: Albums
Posts: 1,939
I use both FF and APS-C, both being 24MP. In most images I capture I cannot tell much difference between them. If anything K3II captures images with finer details than Sony A7, as the K3II do not have an AA-filter on the sensor, which A7 have.
There is a much bigger difference between images captured by my K3II and K7, than the difference between K3II and A7.

Between K3II and A7 it's more about how each individual lens perform and when you reach the limitation of each format that you notice a difference.
- If you need maximum reach of focal length, APS-C will have an advantage.
- If you need most shallow DOF, FF will have an advantage.
- If you need to shoot in dark conditions, FF will have an advantage.

I you need to stop down the lenses to capture increased DOF there will not be a major difference between these two formats as you need to stop down the lens further on FF which basically disables the difference between the formats. Then it will be more anout how each lens perform or if there is a difference in resolution between the formats.

There are other advantages of FF, like increased dynamic range and improved color rendition. But the difference between formats on these things are often small and can be difficult to notice outside lab tests. It's basically like comparing ISO100 images with ISO200 from the same camera.

Last edited by Fogel70; 06-18-2018 at 09:19 PM.
06-18-2018, 10:24 PM   #6
Veteran Member




Join Date: Sep 2017
Location: Medellín
Posts: 531
QuoteOriginally posted by tibbitts Quote
I think the difference is still "grain" in the sense of noise, plus sharpness, plus depth of field. Comparisons are model-depended, though - for example if you compare a higher pixel count APS vs. a lower pixel count full frame, that's a complicated comparison.
When you say sharpness, do you mean "FF is sharper than APS-C"?

Gesendet von meinem Mi A1 mit Tapatalk

---------- Post added 06-18-18 at 10:54 PM ----------

QuoteOriginally posted by northcoastgreg Quote
You can't put a number on the difference between full-frame and APS-C. Full-frame is "better." How much better is largely subjective. Some people find the difference quite dramatic. Others not so much. I'm in the latter group. While I recognize the superiority of FF to APS-C, in actual practice, I don't see much difference. I go twice a month to a photo critique held by the local camera club. I see all kinds of photos, printed anywhere from 14 to 20 inches in size. At that size, you can't tell what kind of camera shot the pics. At that size, we've been fooled by iphone photos. At larger print sizes, all other things being equal, FF has an advantage — though perhaps not as big an advantage as some imagine. There's also an ISO and narrow DOF advantage with FF that some people find decisive to their photography.
This is so true. Smartphones have become very capable of delivering excellent results. Their limitations keep being the same. Pixel pitch with it's limitations and print size, maybe their fixed focal length. Noise and low light are their bane. But at the end it's the end result what matters.

Depth of field really is the same for any format at the same focal length and settings, it's just that smaller formats are like cropping (or "zooming in") on an image. That makes the apparent DOF narrower for bigger formats.
Continuing with that idea, a smaller sensor requires a faster lens for the same apparent DOF, but benefits from the added light gathering capacity. You can see that by comparing MF or even LF lenses with FF lenses. They are considerably slower. F/2 lenses are quite rare on MF, while F/1.4 lenses are quite common on 35mm, F/1.2 not so much but even F/1.0 lenses exist.
OOH, you have a lighter system and that means taking pictures longer, hiking further or just getting less tired. OTOH, you deal with more noise and less low light quality images. That doesn't mean APS-C is bad. Quite the contrary. Systems have become so good you can get profesional results with any format. It just depends on specific needs and cost effectiveness. Captivating images always have and will keep being a result of a good photographer rather than his gear.

Gesendet von meinem Mi A1 mit Tapatalk
06-18-2018, 11:38 PM   #7
Resident fiddler
Loyal Site Supporter
LensBeginner's Avatar

Join Date: Sep 2014
Photos: Albums
Posts: 4,477
There's no "better"... each sensor size is a set of compromises, and you can often shoot the very same image - framing, noise levels, depth of field, etc. - on different sensors.
Only thing, each sensor has a bias towards one point in the scale, so it will be easier to shoot shallow DoF pictures on full frame than on a smartphone, and to have pictures with little noise, but at the expense of some other parameter.
For instance, smartphone picture will have greater DoF, the catch is that sometimes tbis is not desirable (portraits), sometimes there's so much of it (wide angle) that more of it just gets wasted.
06-27-2018, 04:47 PM   #8
Site Supporter
Site Supporter
johnha's Avatar

Join Date: Apr 2012
Location: Lancashire, UK
Photos: Albums
Posts: 501
It's not a simple as grain or resolution as rendered by the film or sensor. The APS-C format came from APS film where the film manufacturers claimed that better film technology allowed the format to be smaller but yield the same resolution as 35mm. The larger the format, the harder it is to make excellent lenses with similar apertures (more glass is required which increases cost, size & weight). Thus medium format lenses are much bigger, heavier & costlier than 35mm lenses but still don't resolve the same detail (the larger format makes up for this). Thus, If I use a P6x7 lens on 35mm, I'm gaining weight & bulk and losing resolution compared to the same focal length lens designed for the 35mm format. I'll always be using the centre of the lens though, so softness and distortion towards the edges no longer issues.

06-29-2018, 08:04 PM - 1 Like   #9
Site Supporter
Site Supporter




Join Date: Dec 2008
Location: Eugene, Oregon
Photos: Albums
Posts: 57
Original Poster
QuoteOriginally posted by adam Quote
it's the same idea, except grain gets replaced by pixel pitch. A bigger sensor means bigger pixel pitch (=less noise/better color) or more pixels without sacrificing pixel pitch (=higher resolution) compared to a smaller sensor.

Here's a hands-on example and explanation:
how & why sensor size affects image quality (aps-c vs ff vs compact) - pentaxforums.com
thank you!

---------- Post added 06-29-2018 at 08:06 PM ----------

QuoteOriginally posted by johnha Quote
It's not a simple as grain or resolution as rendered by the film or sensor. The APS-C format came from APS film where the film manufacturers claimed that better film technology allowed the format to be smaller but yield the same resolution as 35mm. The larger the format, the harder it is to make excellent lenses with similar apertures (more glass is required which increases cost, size & weight). Thus medium format lenses are much bigger, heavier & costlier than 35mm lenses but still don't resolve the same detail (the larger format makes up for this). Thus, If I use a P6x7 lens on 35mm, I'm gaining weight & bulk and losing resolution compared to the same focal length lens designed for the 35mm format. I'll always be using the centre of the lens though, so softness and distortion towards the edges no longer issues.
Excellent! Thank you.

---------- Post added 06-29-2018 at 08:07 PM ----------

QuoteOriginally posted by LensBeginner Quote
There's no "better"... each sensor size is a set of compromises, and you can often shoot the very same image - framing, noise levels, depth of field, etc. - on different sensors.
Only thing, each sensor has a bias towards one point in the scale, so it will be easier to shoot shallow DoF pictures on full frame than on a smartphone, and to have pictures with little noise, but at the expense of some other parameter.
For instance, smartphone picture will have greater DoF, the catch is that sometimes tbis is not desirable (portraits), sometimes there's so much of it (wide angle) that more of it just gets wasted.
Thanks
06-30-2018, 01:06 AM   #10
Pentaxian




Join Date: Dec 2011
Posts: 1,923
QuoteOriginally posted by 3party Quote
I fully understand why a 36 x 24 negative, all things being equal, will yield a superior print to that from a 24 x 18 neg. The reason, in a word, is grain. But I do not understand digital photography well enough to understand how, exactly, the larger sensor yields a better result. It ain't grain!
It is rather simple and you are both right and wrong.

It is actually simply about the need to magnify things. An APSC sensor has x2,25 less area than a 36x24mm one. So for any same size print output you need to magnify it by x1,5 (diagonal) or x2,25 (area).

This magnification makes imperfections (analog film grain, digital "wrong luminance" noise pixels) x1,5 times easier / more visible.
This also is behind the "DoF" differences as that is defined by acceptable airy / unsharp disk diameters and those get magnified as well.

The quality on sensor is the exact same one. And if you would enlarge/print the APSC thing to a smaller scale (e.g. x1,5 smaller) there would be zero differences.

It is all about perception only, not sensors per se.

If you print both FF and APSC images to the same size and reduce your viewing distance to the FF print only by x1,5 then again the perceived quality (noise, dynamic range, DoF, background blur...) would be the exact same.
07-02-2018, 03:31 AM   #11
Pentaxian
MJKoski's Avatar

Join Date: Aug 2016
Posts: 1,236
Then there is a catch. For example KP with properly executed pixel-shift yields as good and even better results than K-1 without pixel-shift. Given that sharp enough lens is used and diffraction does not melt away the details.
07-02-2018, 08:41 AM   #12
Pentaxian
Wheatfield's Avatar

Join Date: Apr 2008
Location: The wheatfields of Canada
Photos: Albums
Posts: 10,766
QuoteOriginally posted by 3party Quote
I fully understand why a 36 x 24 negative, all things being equal, will yield a superior print to that from a 24 x 18 neg. The reason, in a word, is grain. But I do not understand digital photography well enough to understand how, exactly, the larger sensor yields a better result. It ain't grain! What I am trying to figure out is this:
Lets say the difference in maximum quality between 36 x 24 and 24 x 18 negatives is 10 compared with 6. If full-frame digital is a 10, how do C-sensor images compare? 6? 7? 5?

Thank you for taking the time to read my question.

btw...I still have my Pentax LX. It is MUCH smaller than my K3, so comparing full-frame with full-frame, the K1 is ginormous.
I was one of the people who thought "meh, full frame, schmull frame". That was until I got my hands on a full frame camera. You can try to cut it down to the numbers, figure its all about pixel pitch, noise or whatever, but there is more to it than that, and I really don't know what that "more" is.
It's like saying the Limited Lenses are sprinkled with pixie dust. Who knows what that it?
The K5 and the K1 have the same pixel pitch, therefore they should have the same image quality within the K5's 16mp resolution. I can tell you with great certainty that the K1 files, even when both are downsized to a large screen resolution, have more depth and roundness to them (whatever that is, it's the only adjectives I can find to describe it). I found the same thing when I made the jump from 6x7 to 4x5 film. At an 11x14 print size, there wasn't much to say regarding grain, but the tonal transitions were much smoother. I find the same thing with full frame compared to APS-C.
07-03-2018, 09:23 AM   #13
Journeyman Cat Wrangler
Loyal Site Supporter
SSGGeezer's Avatar

Join Date: Jun 2017
Location: Maine, U.S.
Photos: Gallery | Albums
Posts: 3,325
QuoteOriginally posted by Wheatfield Quote
I was one of the people who thought "meh, full frame, schmull frame". That was until I got my hands on a full frame camera. You can try to cut it down to the numbers, figure its all about pixel pitch, noise or whatever, but there is more to it than that, and I really don't know what that "more" is.
It's like saying the Limited Lenses are sprinkled with pixie dust. Who knows what that it?
The K5 and the K1 have the same pixel pitch, therefore they should have the same image quality within the K5's 16mp resolution. I can tell you with great certainty that the K1 files, even when both are downsized to a large screen resolution, have more depth and roundness to them (whatever that is, it's the only adjectives I can find to describe it). I found the same thing when I made the jump from 6x7 to 4x5 film. At an 11x14 print size, there wasn't much to say regarding grain, but the tonal transitions were much smoother. I find the same thing with full frame compared to APS-C.
Since I have only played with a K-1 in the store, it was interesting to see how you could actually describe the differences between a 16Mp K-5 and a K-1 in crop mode. Are they also the same sensor family, but larger portions of the wafer used in the K-1?
07-03-2018, 10:39 AM   #14
Loyal Site Supporter
Loyal Site Supporter
Mikesul's Avatar

Join Date: Sep 2009
Location: Phoenix, AZ
Posts: 4,880
No, I suspect they are different sensor families.
07-04-2018, 07:50 PM   #15
Pentaxian
Wheatfield's Avatar

Join Date: Apr 2008
Location: The wheatfields of Canada
Photos: Albums
Posts: 10,766
QuoteOriginally posted by SSGGeezer Quote
Since I have only played with a K-1 in the store, it was interesting to see how you could actually describe the differences between a 16Mp K-5 and a K-1 in crop mode. Are they also the same sensor family, but larger portions of the wafer used in the K-1?
Note I am not talking about the K1 in crop mode. I would expect in crop mode the K1 and the K5 would be pretty much of a muchness as they are then both the same format, but also the same pixel pitch and pixel count.
As was noted elsewhere, it has to do with how much magnification is required to get to a specific size. The K1 will always be magnified about a third less than an APS-C camera. Obviously it is also capturing gobs more detail with the same framing (different focal length to equalize)
Drop both cameras outputs down to web size and most, if not all of the K1's advantage disappears. The internet really is the great quality killer of photography. I make largish prints, generally around 11x14. At this print size the difference between the two cameras is quite startling. Even the K3, with it's 50% more pixels than the K5 doesn't hold up to the K1. The lower magnification is what makes the difference.
If you shoot multiple film formats you will find the same thing. Moving from 35mm to 6x7 is night and day. Moving from 35mm to 4x5 is bigger than I have adjectives for.
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, 35mm, advantage, aps-c, difference in quality, dof, ff, film, format, full-frame, grain, lens, lenses, light, noise, pentax, pentax news, pentax rumors, pitch, pixel, quality, resolution, results, sensor, size, weight
Thread Tools Search this Thread
Search this Thread:

Advanced Search


Similar Threads
Thread Thread Starter Forum Replies Last Post
Some questions about buying sony full frame + adapters + pentax full frame lens jhlxxx Pentax Full Frame 8 06-14-2017 05:13 PM
Full frame or no full frame.... Deedee Pentax K-3 14 10-08-2013 05:39 AM
Quality difference between FA and DA lenses jatrax Pentax SLR Lens Discussion 35 03-01-2013 08:39 PM
Difference Between Full Frame (35mm) Sensor & Cropped (APS-C) Sensor richard balonglong Photographic Industry and Professionals 22 06-28-2012 02:20 AM
Quality difference between Adaptall and Adaptall 2 Spodeworld Pentax SLR Lens Discussion 22 03-30-2012 08:52 PM



All times are GMT -7. The time now is 07:34 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