Forgot Password
Pentax Camera Forums Home
 

Reply
Show Printable Version Search this Thread
03-08-2012, 04:02 PM   #316
Site Supporter




Join Date: Feb 2011
Posts: 4,892
QuoteOriginally posted by beholder3 Quote
I would recommend accepting reality first.
I think I have a reasonable technical background, and I consider his analysis, especially of 'equivalence', largely correct.

03-08-2012, 04:19 PM   #317
Site Supporter
cali92rs's Avatar

Join Date: May 2011
Location: Long Beach, CA
Posts: 3,204
QuoteOriginally posted by bossa Quote
If Pentax has no plans to bring out a FF DSLR then I would hope RICOH would release a FF sensor module K mount adapter for GXR. The logic of making a modular camera and leaving out the K mount (which you own) seems decidedly odd. It's hard to believe that the would ignore it unless they have 'other plans'.
This is what I want...
The GXR is very intriguing to me. A FF K-mount would definitely get me to buy one.

I have read somewhere that Ricoh is planning to refresh the GXR, so maybe it is in the works on that end??
03-08-2012, 04:40 PM   #318
Pentaxian
twitch's Avatar

Join Date: Nov 2009
Posts: 4,571
This is not my photo, but that of a Pentax forums member who is now using a 5DII. I hope he won't mind me posting this, but it seems at least one reason he's made the move is so he can use fast wide lenses, here's one of his shots from his stream that is impossible to replicate on APS-C, it's taken with a 35/1.4 wide open.


03-08-2012, 06:02 PM   #319
Pentaxian
bossa's Avatar

Join Date: Jul 2011
Location: Adelaide
Posts: 4,538
On the other hand if you're interested in more DOF field for landscape then APS-C might be the ticket. And the fact that you get cheaper long lenses is also a plus for APS-C. I'd like to see the D800 cropped output mode results. I know it's only 15mpx but that should be neither here nor there in the end.

03-08-2012, 07:47 PM   #320
Veteran Member




Join Date: Jan 2008
Location: CT, USA
Posts: 499
QuoteOriginally posted by bossa Quote
On the other hand if you're interested in more DOF field for landscape then APS-C might be the ticket. And the fact that you get cheaper long lenses is also a plus for APS-C. I'd like to see the D800 cropped output mode results. I know it's only 15mpx but that should be neither here nor there in the end.
If you reach DOF "limitations" in FF (unlikely as a stop and a third down gets you the same DOF as APS-C, and you run into diffraction softness a stop and a third beyond where you do for APS-C, both of which occur at a large enough aperture that you won't encounter the minimum aperture available very often), you can crop to the size of APS-C and get exactly what you would get on APS-C. The only difference there has ever been is what pixel count you'll have in the cropped image. With the D800, you aren't even losing pixel density to any extent that matters. Further, the only "need" to do this is where you are using your longest focal length lens and have the need for a smaller angle of view. The supposed "reasons" for the cropped format are the ones in question, more and more, not the "reasons" for FF, which has always included the entirety of the range of image possibilities of APS-C. The reverse is not true, and never will be, because the lenses to allow all the same possibilities don't exist in the cropped format, and never will, because the cropped format is playing to a price-driven audience that would never pay for truly "equivalent" lenses.
03-08-2012, 08:48 PM - 1 Like   #321
Pentaxian




Join Date: Jan 2009
Location: Nevada, USA
Posts: 465
QuoteOriginally posted by jsherman999 Quote
A few folks [..snip...] are choosing to crank up the Ornery meter about this and be willfully obstinate, even though it's been explained countless times.
Every forum has a few folks that seem incapable of distinguishing personal preference from universal edict. Doesn't matter if the topic is photography, pizza crust or politics, some will insist that their view on an issue which is clearly a matter of personal like or dislike is the only sane view possible.

"I like thin crust pizza. There is absolutely no reason for that thick crust garbage. People who claim they like thick crust pizza only say that because they are deluded. I must correct their misconception of what they like."

Discussion degrades to rather silly extremes as these folks try to convince others that their viewpoint is the only sane viewpoint. Characteristics of said discussion include the following.

1) Railing against extreme exaggerations of the opposing viewpoint: "razor-thin DOF." I haven't heard a single FF proponent say they wanted a razor thin DOF, but the FF proponent's desire for a 1+ stop decrease in DOF does not in fact always mean razor-thin, and can be used in many real photographic situations to give greater subject isolation without blurring important details.

2) Seeing the world through incredibly limiting blinders: "increased DOF control would be useless in 99% of photography." Maybe for macro and some types of landscape. But photography encompasses a much broader range of expression than any one enthusiast can hope to appreciate.

3) Insulting others: "just look at any print publication - all their images have large DOF." Besides being patently untrue, this kind of argument implies one hasn't taken the slightest interest in photography.

An obvious and undisputable conclusion from simple math and perusal of available lenses, is that possible images from APS-C are a subset of images from FF, with respect to DOF. I don't have a problem at all that some prefer images within the APS-C subset. I really like many of the images I've seen posted by the "FF DOF control is useless" contingent. They are likely much better than mine will ever be. But that they insist that others must also live within that subset is quite silly.

My advice? Ignore those who try to persuade you to live within the constraints of what they like. I've never seen discussion change the "my personal preference must be universal" mindset.
03-08-2012, 09:59 PM   #322
Veteran Member
Chex's Avatar

Join Date: Feb 2011
Location: The 'Stoke, British Columbia
Photos: Gallery
Posts: 1,700
QuoteOriginally posted by beholder3 Quote
Are FF 450/2.8s the same price as 300/2.8s on APSC?
Well the $6000 difference is nothing, right? Telephotography/Birders/Wildlife doesn't need large apertures, right?
But wide angles do. Because you seldomly shoot brightly lit landscapes with a wide angle, but you always use them on people in dark rooms.
Do they even make a 300 f2.8 that isn't FF glass USED on APS-C body?
What stops someone shooting with a D800 from cropping his shot with a 300 f2.8 down and having at least as good as IQ as a K-5.. or better because the AF would be faster and more accurate.
Sure a 400 f2.8 would be nice, but realisticly there are few uses you would actually need a f2.8 at that focal length, f4 would be a much better and cost effective solution.. besides you need to consider the lack of DoF on APS-C vs FF.. that 300 f2.8 is closer to a 450mm f4 or f4.5 than a f2.8.. so you can run your numbers again if you really want.
03-08-2012, 10:41 PM   #323
Veteran Member
Chex's Avatar

Join Date: Feb 2011
Location: The 'Stoke, British Columbia
Photos: Gallery
Posts: 1,700
QuoteOriginally posted by bossa Quote
The second I saw that picture of the dog on the other thread I knew it'd be almost impossible to shoot it on APS-C.

Using my iPhone DOF calculator I get the following:

FULLF: 50mm F/3.2 @ 2 meters: DOF = 309.02mm
APS-C: 31mm F/1.8 @ 2 meters: DOF = 304.89mm
APS-C: 35mm F/2.3 @ 2 meters: DOF = 305.63

FULLF: 50mm F/2.62 @ 2 meters: DOF = 252.52mm
APS-C: 30mm F/1.40 @ 2 meters: DOF = 252.75 (Sigma)

FULLF: 50mm F/2.00 @ 2 meters: DOF = 192.44mm
APS-C: 30mm F/1.07 @ 2 meters: DOF = 192.86mm

APS-C: 31mm F/1.14 @ 2 meters: DOF = 192.13
APS-C: 35 mm F/1.45 @ 2meters: DOF = 192.01

FULLF: 50mm F/1.40 @ 2 meters: DOF = 134.55mm
APS-C: 30mm F/0.75 @ 2 meters: DOF = 135.02
APS-C: 31mm F/0.80 @ 2 meters: DOF = 134.88mm
APS-C: 35mm F/1.02 @ 2 meters: DOF = 134.91

FULLF: 50mm F/1.20 @ 2 meters: DOF = 115.3mm
APS-C: 30mm F/0.64 @ 2 meters: DOF = 115.18
APS-C: 31mm F/0.68 @ 2 meters: DOF = 114.61mm
APS-C: 35mm F/0.087 @ 2 meters: DOF = 115.03

As stated earlier the lenses would be sharpening up on FF at the smaller apertures and clearing up CA and PF etc too...
Nikon's 24mm f1.4 sure would be hard to replicate on APS-C
FF = 24mm f1.4 @ 2meters = 594.8mm with a 73.74 degree width/53.13 degree height FoV
APS-C = 16mm f1.0 @ 2 meters =640mm with a 73.05 degree width/52.27 degree height FoV
Whats closest available...
DA 15 Ltd (great lens)
15mm f4 @ 2meters = 5630mm with a 76.62 Width/55.25 Height FoV

Any 24mm at f6.7 @ 2 meters = 5319mm ... so even their MUCH cheaper 24mm 2.8 (same price range as the DA 15 Ltd) out performs it for DoF control.
Nikon 24mm f2.8 @ 2 meters = 1272mm

03-08-2012, 11:43 PM   #324
Pentaxian
Asahiflex's Avatar

Join Date: Jan 2008
Location: Netherlands
Photos: Gallery
Posts: 2,753
QuoteOriginally posted by bossa Quote
If Pentax has no plans to bring out a FF DSLR then I would hope RICOH would release a FF sensor module K mount adapter for GXR. The logic of making a modular camera and leaving out the K mount (which you own) seems decidedly odd. It's hard to believe that the would ignore it unless they have 'other plans'.
Maybe you missed the important news that Ricoh's camera division is now under Pentax's control. What that means for the GXR series is anyone's guess.
03-09-2012, 12:39 AM   #325
Veteran Member
eurostar's Avatar

Join Date: Dec 2006
Location: Albareto, Italy
Photos: Gallery
Posts: 813
QuoteOriginally posted by Asahiflex Quote
Maybe you missed the important news that Ricoh's camera division is now under Pentax's control. What that means for the GXR series is anyone's guess.
If I am not mistaken, the idea of a camera with modules made of lenses AND sensors was patented by Pentax many years ago, so I hope Pentax will keep the GXR around, revamped and revisited, but around. Especially as a camera with separated sensor and separated lens mount, I see it with potential. Instead of having to learn a new design of camera controls every two generations of camera, I would gladly have just to buy a new sensor while keeping the old layout to which I am accustomed. Just I would like to have a mount for AF Pentax lenses and one for M rangefinder lenses...
03-09-2012, 01:09 AM   #326
Loyal Site Supporter
drougge's Avatar

Join Date: Jan 2010
Location: Malmö
Photos: Gallery
Posts: 787
QuoteOriginally posted by beholder3 Quote
I would recommend accepting reality first.
What reality would that be? That people on the internet will never agree? I'm fairly comfortable with that.

If on the other hand you want me to think the same numeric aperture is the same thing regardless lens length (or sensor format, if you prefer), I'm afraid I'm going to have to invoke my internet-given right to say you're wrong.
03-09-2012, 01:38 AM   #327
Veteran Member
fikkser's Avatar

Join Date: May 2010
Location: Borlänge, Sweden
Posts: 373
QuoteOriginally posted by twitch Quote
This is not my photo, but that of a Pentax forums member who is now using a 5DII. I hope he won't mind me posting this, but it seems at least one reason he's made the move is so he can use fast wide lenses, here's one of his shots from his stream that is impossible to replicate on APS-C, it's taken with a 35/1.4 wide open.


:-)

I bought a 5d for that effect. The problem is that I use manual glass and manual focusing with fast wide angle primes is near impossible, that picture would be quite hard to shoot because how small the girl is, it's almost impossible to see where the focus is in the viewfinder. It's far easier to focus with a 55 1,2 on aps-c IMO. I even get problems with my 21mm f3,8 on ff. People want FF for manual primes, but it isn't all good.
03-09-2012, 01:49 AM   #328
Pentaxian
bossa's Avatar

Join Date: Jul 2011
Location: Adelaide
Posts: 4,538
QuoteOriginally posted by Asahiflex Quote
Maybe you missed the important news that Ricoh's camera division is now under Pentax's control. What that means for the GXR series is anyone's guess.
I started a thread about that so I'm pretty sure I didn't miss that news. Just what that means is anyone's guess though. It might mean that the GXR will become a Pentax camera in it's next incarnation or not.

Regardless, I won't be buying any more Pentax gear and I'll be saving for a new Nikon system over the year. If Pentax doesn't get it's sh*t in a pile by Photokina it's goodbye from me.
03-09-2012, 01:56 AM   #329
Pentaxian
Clavius's Avatar

Join Date: Feb 2011
Location: De Klundert
Photos: Gallery
Posts: 4,115
QuoteOriginally posted by fikkser Quote
:-)

I bought a 5d for that effect. The problem is that I use manual glass and manual focusing with fast wide angle primes is near impossible, that picture would be quite hard to shoot because how small the girl is, it's almost impossible to see where the focus is in the viewfinder. It's far easier to focus with a 55 1,2 on aps-c IMO. I even get problems with my 21mm f3,8 on ff. People want FF for manual primes, but it isn't all good.
If the FPS of your 5D is high enough, you can apply the same cheat/trick as I do with my 55 1.2 on my K5. High shutter speed, continueous drive. Use the VF for composing only. And then shamelessly machinegun whilst focussing. Then there's always a few hits in there somewhere. I know, it's (very) far from an elegant solution. It's brute force, but it works very well.
03-09-2012, 02:49 AM   #330
Pentaxian
falconeye's Avatar

Join Date: Jan 2008
Location: Munich, Alps, Germany
Photos: Gallery
Posts: 6,862
QuoteOriginally posted by Asahiflex Quote
Maybe you missed the important news that Ricoh's camera division is now under Pentax's control. What that means for the GXR series is anyone's guess.
They have been merged. Who controls who remains to be seen ...
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!
dream, frame, full-frame, pentax, pentax full frame
Thread Tools Search this Thread
Search this Thread:

Advanced Search


Similar Threads
Thread Thread Starter Forum Replies Last Post
Full frame pentax cem.kumuk Pentax DSLR Discussion 11 11-12-2010 03:13 PM
Pentax and Full Frame... Shutter-bug Photographic Technique 60 11-03-2010 10:03 AM
Pentax A 50/1.2 on Full Frame aegisphan Pentax SLR Lens Discussion 23 10-28-2010 04:16 PM
Full Frame Pentax a pipe dream? Athiril Pentax DSLR Discussion 5 08-18-2008 02:10 AM
My Dream of a K20D, crushed..... Mr Hyde Pentax DSLR Discussion 10 04-10-2008 02:13 PM



All times are GMT -7. The time now is 07:35 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