Forgot Password
Pentax Camera Forums Home
 

Reply
Show Printable Version Search this Thread
07-06-2015, 02:40 PM   #91
Pentaxian
mattb123's Avatar

Join Date: Apr 2010
Location: Colorado High Country
Photos: Gallery
Posts: 7,032
QuoteOriginally posted by Rondec Quote
Ian Shive was on Creative Live talking about photographing national parks. He uses Canon 5D Mk II/III to do his photographing, but he said that he shoots stopped down to f22 most of the time.

It is funny to me, because my perception is that at f22 on a full frame because of diffraction, you are pretty unlikely to see much benefit over APS-C, but his perspective is that he wants everything in focus and photos are more about composition and light and less about sharpness anyway. He has nice results, but I bet the pixel peepers here on the forum would have a cow about the sharpness he is losing because of diffraction.
I've heard of a lot of landscape photographers doing this. A friend of mine stops all the way down regularly and he thinks diffraction is just something hobbyists are concerned with for the most part.

07-06-2015, 05:57 PM   #92
Pentaxian
normhead's Avatar

Join Date: Jun 2007
Location: Near Algonquin Park
Photos: Gallery | Albums
Posts: 23,735
There's always been different size films and sensors, bigger and smaller than 35mm. The current focus on 35mm sensors is simply idiocy. Maybe it's the right format for you maybe it's not, but, all things considered, it's pretty unlikely that it will be. In fact it's unlikely to be any of them. When you have a spectrum that goes from Q to 4/3 to APS-c to FF to 645, the odds of one of those formats being dominant or the "best" in every way is pretty unlikely. No one format size is going to be anything more than niche, even if everyone shot exactly what they wanted without regard to price.

QuoteQuote:
A FF sensor is 2,334 times the size of the APS-C sensor.
That's 1.3 stops. And if you wish to keep your DoF constant, you have to shoot 1.3 stop slower aperture using an FF. Which means you're using the same amount of light for the same DoF in both systems. That is the beauty of equivalence. You can shoot for less DoF using an FF at the open Aperture end of the spectrum, but only by shooting with narrower DoF.

Last edited by normhead; 07-06-2015 at 06:43 PM.
07-06-2015, 06:08 PM   #93
Lens Buying Addict
monochrome's Avatar

Join Date: Mar 2008
Location: Kirkwood (St. Louis) MO
Photos: Gallery | Albums
Posts: 19,461
QuoteOriginally posted by repaap Quote
Okay, no more excuses...then it will not make any impact on my shots. I just want that thing. First pentax D FF which will come available...after so long wait. There.
Want, yes. Able to afford, not so much. In reality I'd need to sell everything in my Profile page other than the 3 Princesses to own the FF and the two standard f/2.8 zooms.

And what would be the point of that?
07-06-2015, 06:35 PM   #94
osv
Pentaxian




Join Date: Mar 2007
Location: So Cal
Photos: Gallery
Posts: 2,080
QuoteOriginally posted by Rondec Quote
It is funny to me, because my perception is that at f22 on a full frame because of diffraction, you are pretty unlikely to see much benefit over APS-C
f/22 on ff has about the same diffraction as f/14 on crop, don't you shoot the da15 stopped down at f/14, or worse?

that doesn't make it right

07-06-2015, 06:36 PM   #95
Loyal Site Supporter




Join Date: Mar 2009
Location: Southern Indiana
Photos: Gallery
Posts: 14,948
QuoteOriginally posted by osv Quote
f/22 on ff has about the same diffraction as f/14 on crop, don't you shoot the da15 stopped down at f/14, or worse?

that doesn't make it right
I don't usually shoot stopped down more than f8 or f10 max on APS-C. Not even with the DA 15.
07-06-2015, 06:46 PM   #96
Pentaxian
normhead's Avatar

Join Date: Jun 2007
Location: Near Algonquin Park
Photos: Gallery | Albums
Posts: 23,735
QuoteQuote:
f/22 on ff has about the same diffraction as f/14 on crop, don't you shoot the da15 stopped down at f/14, or worse?
The only thing that affects diffraction is pixel size, not sensor size. A 51 MP FF sensor will have the same diffraction limit as a 24 MP APS-c.

In terms of diffraction, say you're using APS-c and FF both at 24 MP. The APS-c has a lower diffraction limit, but more DoF, by the time you match the DOF, your ƒ14 APS-c is going to be equivalent to ƒ 22 FF, so it's pretty much the same.

As a general rule I don't shoot over ƒ16 on APS-c or ƒ22, on FF, so it works out pretty much equivalent. In fact it's rare I find the need to go above ƒ8 on APS-c.

If you look at the Tamron 90 on APS-c the diffraction limit seems to occur at ƒ4, IQ degrades after that.
http://www.photozone.de/nikon--nikkor-aps-c-lens-tests/283-tamron-af-90mm-f2...review?start=1

ON the FX Nikon test it's the same diffraction after ƒ5.6 so in practice, DX and FX are pretty much identical in terms of the diffraction limit if you take DoF into account and since you can shoot APS-c a stop wonder for the same DOF, the total light is also the same.
http://www.photozone.de/nikon_ff/902-tamron90f28vcfx?start=1

Last edited by normhead; 07-06-2015 at 07:09 PM.
07-06-2015, 07:17 PM - 1 Like   #97
osv
Pentaxian




Join Date: Mar 2007
Location: So Cal
Photos: Gallery
Posts: 2,080
QuoteOriginally posted by Rondec Quote
I don't usually shoot stopped down more than f8 or f10 max on APS-C. Not even with the DA 15.
i'm referring to your post of that cool winter landscape photo, with the rock in the right-hand corner, by the lake... you couldn't get the rock in focus at normal apertures, because it was so close.

"Ansel Adams, "The Camera," page 74 "...With diffraction causing some loss of sharpness at small apertures, and certain aberrations degrading image quality at large stops, a lens usually gives its best image quality somewhere near the middle of its aperture range."

i don't know why anyone would want to shoot f/22 on ff, or f/14 on crop, unless it was weak glass or a dire situation, like that rock by the lake.

---------- Post added 07-06-15 at 08:08 PM ----------

QuoteOriginally posted by normhead Quote
The only thing that affects diffraction is pixel size, not sensor size. A 51 MP FF sensor will have the same diffraction limit as a 24 MP APS-c.
"Diffraction depends on the lens, not the sensor. A higher megapixel count won’t increase diffraction. There’s a common misconception that a higher megapixel count increases diffraction because most of the time, images are examined at 100%. If you normalized the images from two cameras with the same lens to the same pixel count/print size, you’ll realize that both of the images have the same amount of diffraction."
Read more on NikonRumors.com: Motion blur, diffraction and noise are not impacted by high megapixel count | Nikon Rumors

also:
What Does 'Diffraction-Limited' Mean? | TalkEmount - Sony Alpha E-Mount User Group

QuoteOriginally posted by normhead Quote
If you look at the Tamron 90
you are thinking in terms of f/2 = f/2, but when the sensors are different sizes at the same focal length, it's apples vs. oranges.

there has to be equivalence before there can be an accurate comparison.
07-06-2015, 09:57 PM   #98
Pentaxian




Join Date: May 2009
Location: Ponoka Alberta Canada
Photos: Gallery
Posts: 449
QuoteOriginally posted by osv Quote
i'm referring to your post of that cool winter landscape photo, with the rock in the right-hand corner, by the lake... you couldn't get the rock in focus at normal apertures, because it was so close.

"Ansel Adams, "The Camera," page 74 "...With diffraction causing some loss of sharpness at small apertures, and certain aberrations degrading image quality at large stops, a lens usually gives its best image quality somewhere near the middle of its aperture range."

i don't know why anyone would want to shoot f/22 on ff, or f/14 on crop, unless it was weak glass or a dire situation, like that rock by the lake.

---------- Post added 07-06-15 at 08:08 PM ----------



"Diffraction depends on the lens, not the sensor. A higher megapixel count won’t increase diffraction. There’s a common misconception that a higher megapixel count increases diffraction because most of the time, images are examined at 100%. If you normalized the images from two cameras with the same lens to the same pixel count/print size, you’ll realize that both of the images have the same amount of diffraction."
Read more on NikonRumors.com: Motion blur, diffraction and noise are not impacted by high megapixel count | Nikon Rumors

also:
What Does 'Diffraction-Limited' Mean? | TalkEmount - Sony Alpha E-Mount User Group



you are thinking in terms of f/2 = f/2, but when the sensors are different sizes at the same focal length, it's apples vs. oranges.

there has to be equivalence before there can be an accurate comparison.

+1


The largest benefit I see going with higher and higher resolution cameras is the less of the need for AA filters, even with a 24mp FF camera with AA we can see aliasing at F/45 well into the realm of diffraction. It not till F/64 where diffraction removes aliasing and provides enough blur for good sampling without false detail.

My wish would be to have a sensor with the pixel density that could sample a lens and not have to worry about aliasing and use diffraction in place of AA filters thru out a lenses av range. This way we can sample the true resolution of a lens without aliasing false detail and eliminate the need for adding blur to the optical formula of a system to combat this aliasing.
Bring on the 150 mp FF camera, this would be a good start please.

The most I stop down with FF is F/13 and that's using a 50mm lens for landscape

07-07-2015, 02:23 AM - 1 Like   #99
Veteran Member
drypenn's Avatar

Join Date: Nov 2012
Photos: Albums
Posts: 948
FF will probably not make me a better photographer (it can even make me worse!), but it's a nice excuse to justify wasting spending money!

If one wants and can afford it, just indulge! Life is too short for such pettifogging! Happiness is a priceless and rare commodity nowadays!
07-07-2015, 02:29 AM   #100
Pentaxian
redcat's Avatar

Join Date: Jul 2014
Location: Paris
Photos: Gallery
Posts: 1,804
QuoteOriginally posted by drypenn Quote
Life is too short for such pettifogging! Happiness is a priceless and rare commodity nowadays
you, I like
you give me more excuse to "spending" money on the next FF =))
07-07-2015, 03:18 AM   #101
New Member




Join Date: Apr 2015
Posts: 20
I don't get the hysteria about FF.
I switch my Pentaxes between APS-C (K50) and Full Frame (MX) regularly and neither of them is superior in all fields.

Other than the MX being a real camera made out of metal, glas and magic vs the K50 being only a digital toy for grownups.

I see my 35mm film photographs always as being better than the digitals, even if they are less perfect, but this is not an issue of the sensor size.
07-07-2015, 05:43 AM   #102
Pentaxian
mecrox's Avatar

Join Date: Apr 2009
Location: Oxford, UK
Photos: Gallery
Posts: 1,912
FF very probably wouldn't improve my photography but would improve my mood, or pleasure in the whole experience. I'd feel more comfortable shooting with what I thought was about as good as it gets. There'd no longer be much if any reason to think a shot was subpar because of the equipment and its limitations. The result would all be down to me. That said, FF would all but wreck my pleasure in street photography as the format is simply too large to take into busy city spaces without hassles and possibly danger, imho. It would be a similar story in domestic situations when people are used to smartphones or compacts and the last thing they want is some monster box pointed at them. FF versus other formats, at least concerning DSLRs, is most certainly not an either/or.
07-07-2015, 06:16 AM   #103
Pentaxian
normhead's Avatar

Join Date: Jun 2007
Location: Near Algonquin Park
Photos: Gallery | Albums
Posts: 23,735
QuoteQuote:
Diffraction depends on the lens, not the sensor. A higher megapixel count won’t increase diffraction. There’s a common misconception that a higher megapixel count increases diffraction because most of the time, images are examined at 100%. If you normalized the images from two cameras with the same lens to the same pixel count/print size, you’ll realize that both of the images have the same amount of diffraction."
This person doesn't really understand how diffraction affects a camera system. . Diffraction itself is always the same, is caused by the lens, and is not affected by pixel size. But how diffraction affects your image? With both CA and diffraction if the diffraction is less than .7 of a pixel you can pretty much discount it as a factor affecting IQ. Once it's more than a pixel it starts to degrade the image. So the diffraction in a low density sensor with large pixel sites maybe be at .7 and unaffected at some theoretical diffraction limit, while the pixel half that size will have diffraction affecting 1.4 pixels and will definitely be affected, contrast and micro contrast.

You can use the information at Nikon Rumours at your peril. The guy may understand a bit about diffraction, but he certainly doesn't understand how it integrates into camera systems.

Just looking at his comment on motion blur he's made the same mistake. Motion blur will be the same. No matter what the sensor size or pixel count, but how many pixels in your image are affected by motion blur is definitely affected by pixel size.

This is really pretty straight forward stuff. Anyone with who's had to take a basic course in lens design, isn't going to make this kind of mistake. It's kind of sad that these people set themselves up as some kind of experts, and then publish on the internet. The internet is really only of use to those with enough technical knowledge to make sense of what some unqualified "know it all" posts.

People get led astray by this kind nonsense.

Last edited by normhead; 07-07-2015 at 06:23 AM.
07-07-2015, 02:10 PM   #104
osv
Pentaxian




Join Date: Mar 2007
Location: So Cal
Photos: Gallery
Posts: 2,080
he's not the only one saying that... here is the simple explanation:

"For the same color and f-ratio, the Airy Disk will have the same diameter, but span a smaller portion of a larger sensor than a smaller sensor, thus resulting in less diffraction softening in the final photo. On the other hand, for the same color and DOF, the Airy Disk spans the same proportion of all sensors, and thus the effect of diffraction softening is the same for all systems at the same DOF." Equivalence
07-07-2015, 03:14 PM   #105
Senior Member




Join Date: Dec 2012
Location: Pekin, IL
Posts: 207
QuoteOriginally posted by normhead Quote
. . . It's kind of sad that these people set themselves up as some kind of experts, and then publish on the internet. The internet is really only of use to those with enough technical knowledge to make sense of what some unqualified "know it all" posts.

People get led astray by this kind nonsense.
That's not necessarily true. I'm an expert. I set all the dials and controls to the "green" settings, and then I aim the camera and push the button. And try not to shake it when I do so. Then a picture appears! It's because each Pentax contains a little Rembrandt. Nikons and Canons only contain miniaturized art-school students.

I do appreciate your posts, though. They cause me to think twice about what really is plausible, and then I become ashamed about some of the things I believed that look like crap when I re-examine them.
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, cameras, control, count, diffraction, dof, f/2, ff, film, frame, frame sensors, full-frame, images, increase, lens, manufacturers, megapixel, observation, pentax, rock, sensor, sensors, size
Thread Tools Search this Thread
Search this Thread:

Advanced Search


Similar Threads
Thread Thread Starter Forum Replies Last Post
How to improve your photographic creations pursang Photographic Technique 15 03-21-2015 10:39 PM
Night Trying to Learn Night Photography v3; How can I improve? Hexism Photo Critique 14 01-14-2015 08:19 PM
Ten household items that can improve your food photography interested_observer Photographic Technique 2 11-17-2013 06:07 PM
Thematic try it backward to improve your photography slip Mini-Challenges, Games, and Photo Stories 2 08-26-2012 07:40 AM
Food How to improve my food photography? ddekadt Photo Critique 12 06-22-2012 08:45 PM



All times are GMT -7. The time now is 08:30 PM. | See also: NikonForums.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