Forgot Password
Pentax Camera Forums Home
 

Reply
Show Printable Version Search this Thread
10-30-2008, 07:40 AM   #31
Veteran Member




Join Date: Nov 2006
Location: Hong Kong
Posts: 1,934
Not Correct for All!

QuoteOriginally posted by Class A Quote
How do you know they are "unable" as oppose to "unwilling" (because of marketing considerations)?
The inability will of course lead to unwillingness.

They have already discontinued most of the FF film lenses they had and how could they rebuild the line overnight?

QuoteQuote:
Noise is mainly affected by sensor size, not pixel size.
With a fixed pixel count, the smaller the sensor size, the smaller the pixel size will be (putting minor variation in between different sensors aside).

QuoteQuote:
Given the same area, a sensor with smaller pixels has more noise per pixel but also has more pixels. Just perform pixel binning to get the same result as the sensor with the larger pixels.
Nope. Adding up and averaging out two or even more *noisy* pixels will not give you a noiseless pixel data. The Physics is only one larger pixel, with more area and full well capacity in receiving light and store more charge, will have less noise, i.e., a higher S/N ratio.

QuoteQuote:
Also, the noise of the higher pixel density sensor will be more fine grained, i.e., more pleasing to the eye.
Not exactly. In-camera processing is required to filter out those colour noise. Noise are random and the RGB channel will not behave the same for different shooting conditions! The best thing is STILL there is LESS noise from the sensor.

QuoteQuote:
There might be a point when the ratio between light sensitive area and light insensitive area gets too unfavourable or read out noise of too small signals from too small pixels becomes a problem, but I don't think you have any evidence that this is the case with any 24MP sensor.
But most measurbation tests so far have told almost the same. Let's wait and see if the 5D MkII could be better (but I bet it should be worse than the D700 anyway - as with the same generation of technology, the lower pixel density and larger pixel area will *always* win, as I have been emphasizing). Even though it looks better, I believe that there are a lot of post-processing to do within the camera before the pictures could "cheat" our eyes.

QuoteQuote:
Freedom = "forced to" unless they have better ISO performance.
The high ISO performance of my 5D is much better than *any* APS-C DSLR (brand regardless) ever made, for the same or close MP count.

QuoteQuote:
Surely that must be a subjective observation based on existing models. How would you substantiate this claim based on physics?
The Physics is CCD/CMOS is a light sensitive charge up device. The total amount of storeable charge is roughly proportional to the sensing area per pixel (charged by the Photons, or just light energy). As the floor noise is always there, the Signal to Noise ratio could only be raised if the total charge can be increased (and thus also the Dynamic Range too, which is just what it is defined).

For further read, you can have a look at:

Clarkvision: Digital Camera Sensor Performance Summary

10-30-2008, 08:06 AM   #32
Pentaxian
Wheatfield's Avatar

Join Date: Apr 2008
Location: The wheatfields of Canada
Posts: 10,131
QuoteOriginally posted by Venturi Quote
I fully realize that it was intentional and planned from an engineering (AND marketing) standpoint by Pentax.
But, for you and I (consumers) and thousands of eBay sellers - it's luck.
I suspect it had as much to do with desperation as anything. By keeping the same register distance, they didn't have to release a new lens line immediately, which they didn't have the resources to do, especially with the hit they took with their full frame DLSR fiasco.
10-30-2008, 08:20 AM   #33
Veteran Member
jeffkrol's Avatar

Join Date: Sep 2006
Location: Wisconsin USA
Photos: Gallery
Posts: 8,435
QuoteOriginally posted by Wheatfield Quote
I suspect it had as much to do with desperation as anything. By keeping the same register distance, they didn't have to release a new lens line immediately, which they didn't have the resources to do, especially with the hit they took with their full frame DLSR fiasco.
Maybe, but mostly historic reasons and marketing.
Pentax released the first DSLR (*ist-D), which was heavily advertised as "backward compatible" yet was completely crippled as to manual metering and old lenses.
The response to re-establish full compatibility was loud and a swift update was released...
My personal take. This was an attempt to judge market reaction to eliminating backward compatibility and failed miserably. Pentax didn't have the guts (resources) ect. to do a surgical strike ala Canon but they were hoping to phase it in. First attempt failed. Second attempt (my own theory) is the funky "brite matte" screen which again disturbed the metering w/ old lenses. Third attempt is eliminating in-body motors....
Conservative
K-mount variations
Lately Pentax introduced some lenses without an aperture ring, suitable for their low-end cameras but not fully compatible with current midrange and top level models. This caused so much concern among Pentax users about a possible end of acclaimed Pentax compatibility, also considering the "simplified" bayonet introduced some years ago on a few budget models. In order to understand what is going on, here follows a technical overview of the variations of Pentax K bayonet from 1975 to date, and an investigation about the limitations when using either a camera or a lens with "crippled" mounts.

Last edited by jeffkrol; 10-30-2008 at 09:35 AM.
10-30-2008, 08:40 AM   #34
Veteran Member
kristoffon's Avatar

Join Date: Aug 2008
Location: Brazil
Posts: 532
QuoteOriginally posted by Big Dave Quote
Actually the mounts and registration distance were retained with the APS-C cameras intentionally for lens compatibility. The RD could easily be reduced, because of the smaller mirror.
As is the case in Canon EF-S lenses...

QuoteOriginally posted by Gooshin Quote
or no mirror at all
This really puzzles me. The greatest advantage of DSLRs is the mirror and viewfinder. I can't understand people who think live view is even remotely close to replacing the real thing.

QuoteOriginally posted by jeffkrol Quote
Third attempt is eliminating in-body motors....
I really doubt that. Even Canon cameras retain in-body motors (at least the APS-C ones, don't know about FF) and many current EF-S mount lenses don't have built-in motors. Cheapness is the name of the game.

10-30-2008, 09:23 AM   #35
Veteran Member
Gooshin's Avatar

Join Date: Sep 2007
Location: Toronto, the one in Canada.
Posts: 5,611
QuoteOriginally posted by kristoffon Quote
This really puzzles me. The greatest advantage of DSLRs is the mirror and viewfinder. I can't understand people who think live view is even remotely close to replacing the real thing.
QuoteOriginally posted by Blue Quote
But then would it be a dslr?
you two must be of the sentimental type..


one of the greatest DISadvantage's of an SLR camera IS the mirror.

lets break it down to the basics.

one, the object of photography is to take pictures.

two, to take a good picture using available tools, the user must see what he is taking pictures of

three, the medium for image recording of the past required that said medium be encased in darkness and was shown light for only a brief period in time, that and the fact that we very well cant SEE through the film.

ergo, to compose our images and adjust focus we must divert the image through any means possible

you have 3 ways of doing this.

one, blind guestimation and math, like my russian Смена-2 camera, where the viewfinder is just a hole used for composition, and focusing would have to be done by actualy measuring the distances...

two, rangefinder design

three, slr design

(i'm not a camera-cologist, so if there are other ways please enlighten me)

overtime, it seems the SLR prevailed, because you got to see through the lens, you got to see the image, the focus, the depth of field, everything was right there, right before your eyes.

what do we sacrafice?

one, space (for a range finder the limiting factor is pretty much the size of the film canisters)

two, durability (whats better than a little bit of moving parts... NO moving parts!)

three, cost (someone hast to build that mirror mechanism)

since we get alot of utility out of this arrangement, everyone shrugs their shoulders and life goes on.


fast forward Y2K, technology improves, say hello to the digital sensor.

the constraints are pretty much the same, we cant see through the sensor, so we need to diver the light, well, we have a good thing going with the mirror, lets do that, okay.

more time goes on, someone says, well, since the digital sensor can showcase the image almost instantly, why dont we just put it up on the LCD screen?

one guy says "there will be overheating problems affecting image quality", another girl says "there isnt enough processing power to do it fast enough", third guy says "our battery power will be compromised", fourth guy says "thats no longer a photo camera, thats a video camera" or "thats not classic photography" or "screw that i'm gonna climb under my rock and use my analog light meters and spend all day long sniffing chemicals because thats REAL photography"

well guess what?

batteries are being made smaller, and last longer

processors are being made smaller, and computer more power

LCD's are made bigger, cheaper, with higher quality

digital light senors are made bigger, cheaper, higherquality, requiring less voltage, producing better results, etc etc etc.


there are already enough threads where people are explaining to the rest of you that Live View has merrits, i know i have used it with great success where "looking through the view finder" would have resulted in me covered in dirt and probably a bad picture.


other advantages, if you're going to allow technology to prosper, you HAVE to allow it to do things its way

autofocus
face/smile recognition
live histogram (why take a picture and chimp on it when you can see it right there before your eyes)

imagine your K20D no more than an inch thick, with a 4X5" LCD on the back at a resolutiong of 640X480 or 800X600! with a 60-70 refresh rate, hardly draining power, with anti glare technologoies.

is this really that bad?

after all, photography is about taking pictures

photography is not about sticking your eye in a little hole and ruining your vision.


*having said that i wont deny that i do enjoy looking through my Super Program

** having said that, i also enjoy drinking beer and spending time with women, if i can sacrifice looking through a large view finder for better images and a smaller camera that offers more versatility for image taking and is bullet proof, i will agree to that sacrifice.

Last edited by Gooshin; 10-30-2008 at 09:29 AM.
10-30-2008, 09:32 AM   #36
Veteran Member
Gooshin's Avatar

Join Date: Sep 2007
Location: Toronto, the one in Canada.
Posts: 5,611
QuoteOriginally posted by kristoffon Quote
I really doubt that. Even Canon cameras retain in-body motors (at least the APS-C ones, don't know about FF) and many current EF-S mount lenses don't have built-in motors. Cheapness is the name of the game.
which, digital camera bodies exactly... have in-body focusing motors?
10-30-2008, 10:09 AM   #37
Moderator
Site Supporter
Blue's Avatar

Join Date: Jun 2008
Location: Florida Hill Country
Photos: Gallery | Albums
Posts: 17,211
QuoteOriginally posted by Gooshin Quote
you two must be of the sentimental type..


one of the greatest DISadvantage's of an SLR camera IS the mirror.

lets break it down to the basics.
Well duh. My comment was more from a Profound statement in regards of the thought of an SLR without a mirror. I have F and K2 for sentimental reflection.

However, in all the bandwidth you used, you failed to mentioned why Canon, Nikon, Pentax still put mirrors in their dSLR bodies. Nikon doesn't use mirrors in their hybrids such as my old 5700.
10-30-2008, 10:16 AM   #38
Veteran Member
Gooshin's Avatar

Join Date: Sep 2007
Location: Toronto, the one in Canada.
Posts: 5,611
QuoteOriginally posted by Blue Quote
Well duh. My comment was more from a Profound statement in regards of the thought of an SLR without a mirror. I have F and K2 for sentimental reflection.

However, in all the bandwidth you used, you failed to mentioned why Canon, Nikon, Pentax still put mirrors in their dSLR bodies. Nikon doesn't use mirrors in their hybrids such as my old 5700.
i never knew i had to mention anything about the future plans of other companies

but since you have trouble coming up with your own theories i'll share mine.

Canon, Nikon and Pentax have lots of glass, lots of very good glass, glass made for 35mm cameras, and some for APS-C, althought as reports are comming in, even those can be used on 35mm frames.

full frame sensors are getting cheaper to produce with a lower defect rate (my assumption based on the wordly technology progression of times gone past)

so going digital FF is become economically feasible.

since you have the bodies, and you have the lenses, and you dont want to waste too much money, you're going to keep doing what your doing.

because if you take out the mirror, you're still going to keep the same register distance, but whats the point? you're just wasting space (and like i said, i have nothing against view finders, its definetly an enjoyable part of photography)



Panasonic on the other hand, said "hey guys, we have this tiny sensor, so.. lets just make everything else tiny"

and they did, go read up the technical specs and reviews/previews of the Panasonic G1 Lumix, i think it would interest anyone that doesnt have a hardcore biased opinion that Pentax is #1 and that the world never changes.

10-30-2008, 10:42 AM   #39
Moderator
Site Supporter
Blue's Avatar

Join Date: Jun 2008
Location: Florida Hill Country
Photos: Gallery | Albums
Posts: 17,211
QuoteOriginally posted by Gooshin Quote
i never knew i had to mention anything about the future plans of other companies

but since you have trouble coming up with your own theories i'll share mine.

Canon, Nikon and Pentax have lots of glass, lots of very good glass, glass made for 35mm cameras, and some for APS-C, althought as reports are comming in, even those can be used on 35mm frames.

full frame sensors are getting cheaper to produce with a lower defect rate (my assumption based on the wordly technology progression of times gone past)

so going digital FF is become economically feasible.

since you have the bodies, and you have the lenses, and you dont want to waste too much money, you're going to keep doing what your doing.

because if you take out the mirror, you're still going to keep the same register distance, but whats the point? you're just wasting space (and like i said, i have nothing against view finders, its definetly an enjoyable part of photography)



Panasonic on the other hand, said "hey guys, we have this tiny sensor, so.. lets just make everything else tiny"

and they did, go read up the technical specs and reviews/previews of the Panasonic G1 Lumix, i think it would interest anyone that doesnt have a hardcore biased opinion that Pentax is #1 and that the world never changes.
The hybrids I mention have a viewfinder. Why has Nikon kept the mirror in their dSLR or more accurately why do the do dSLR bodies? The biggest downfall of the hybrids is the lack of interchangeable lenses.
10-30-2008, 10:49 AM   #40
Veteran Member
Gooshin's Avatar

Join Date: Sep 2007
Location: Toronto, the one in Canada.
Posts: 5,611
QuoteOriginally posted by Blue Quote
The hybrids I mention have a viewfinder. Why has Nikon kept the mirror in their dSLR or more accurately why do the do dSLR bodies? The biggest downfall of the hybrids is the lack of interchangeable lenses.
convention
10-30-2008, 11:03 AM   #41
graphicgr8s
Guest




All pretty interesting but here's the thing. With the crop factor you have to enlarge the image more than FF to get the same output size. Your telephoto lens still projects the same size image in APS it just cuts off part of it. Not bad for tele but sucks for WA. The more you enlarge something the more noise, the more imperfections are visible.
10-30-2008, 11:10 AM   #42
Veteran Member
Gooshin's Avatar

Join Date: Sep 2007
Location: Toronto, the one in Canada.
Posts: 5,611
QuoteOriginally posted by graphicgr8s Quote
All pretty interesting but here's the thing. With the crop factor you have to enlarge the image more than FF to get the same output size. Your telephoto lens still projects the same size image in APS it just cuts off part of it. Not bad for tele but sucks for WA. The more you enlarge something the more noise, the more imperfections are visible.
what?
10-30-2008, 11:32 AM   #43
Veteran Member
kristoffon's Avatar

Join Date: Aug 2008
Location: Brazil
Posts: 532
QuoteOriginally posted by Gooshin Quote
you two must be of the sentimental type..


one of the greatest DISadvantage's of an SLR camera IS the mirror.
Well, you certainly have a point there.

But to me a 1024x768 viewfinder would still be a lousy viewfinder compared to what I see though the lens. And it's dynamic range would be lousy. And it would not be nearly enough to do manual focusing, or to see what the autofocus locked on when using a wide aperture. And increasingly I'm doing more manual focusing simply because it lets me take better photos at wide apertures and for that I even bought a focusing screen.

Also I couldn't care less for live histogram since shooting RAW ISO 200-400 I can compensate +/- 1EV in post processing with negligible loss of image quality.

So, to each his own. I'll stick to DSLRs thank you very much.

QuoteOriginally posted by Gooshin Quote
which, digital camera bodies exactly... have in-body focusing motors?
I'm pretty sure the XSi does. And look at Canon's site, many current EF-S lenses are screw drive, the 18-200 for example.
10-30-2008, 11:38 AM   #44
Veteran Member
Gooshin's Avatar

Join Date: Sep 2007
Location: Toronto, the one in Canada.
Posts: 5,611
as i mentioned in another thread in the general forum

this self portait http://fork.zenfolio.com/img/v4/p704833906.jpg

image was taken using live view on the K20d, while it was upside down at nearly ground level. This should would have been very difficult to take if i actualy had to snake my way down to the ground over the rusty rails, and i'm a flexible guy, some people here are not as mobile due to various reasons.

now imagine that my LCD had a 360* swirl/tilt function and was 4X4 or 4X5", it would open up a door to many more options.

you are too dismissive of the capabilities of LCD screens and live view, esp on a tripod.

the biggest problem right now is the refresh rate, its too slow, once they get the refresh rates of photocamera LCD's to levels higher than your vision, it will be much more pleasant to use.
10-30-2008, 11:47 AM   #45
Site Supporter
stevebrot's Avatar

Join Date: Mar 2007
Location: Vancouver (USA)
Photos: Gallery | Albums
Posts: 27,264
As I scanned through the OP and many comments, a thought occurred to me...
If you don't see any advantage to FF, you obviously have not felt the pain of APS-C!!
I, for one, do feel the pain.

Explanation...
For many of us with a deep background with 35mm and MF film SLRs, the digital APS-C format has significant shortcomings:
  • We dearly miss large, bright viewfinders.
  • We also miss having rectilinear wide-angle options that don't break the bank.
  • For visualization purposes, it is nice to have a normal lens with magnification similar to that of the human eye.
  • There is also the unavoidable magnification of flaws due to the smaller sensor.

Steve

P.S. There is a reason why APS-C was a flop when it was originally introduced for film...
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!
camera, dslr, ff, iso, lenses, lot, photography
Thread Tools Search this Thread
Search this Thread:

Advanced Search


Similar Threads
Thread Thread Starter Forum Replies Last Post
Buying locally, when you can. The advantage. Ed n Georgia General Talk 2 10-26-2010 07:55 AM
Advantage of mixed system yusuf Pentax DSLR Discussion 10 10-05-2010 07:07 AM
One EVIL/MILC/etc advantage Eruditass Non-Pentax Cameras: Canon, Nikon, etc. 21 06-07-2010 05:14 AM
advantage of SDM lenses Wulifou Pentax SLR Lens Discussion 16 10-20-2008 10:02 AM
advantage of CMOS vanguy Pentax DSLR Discussion 4 01-23-2008 10:27 PM



All times are GMT -7. The time now is 01:31 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