August 22, 2014, 10:45:50 AM

Author Topic: I still don't get the crop debate  (Read 10216 times)

LetTheRightLensIn

  • Canon EF 300mm f/2.8L IS II
  • *******
  • Posts: 3433
    • View Profile
Re: I still don't get the crop debate
« Reply #30 on: April 12, 2012, 12:06:03 AM »

yes, what I mean here is that the consequences of pixel density do come into play at normal ISO speeds at the same FOV  when pixel peeping.  This is evidenced by the fact that a 5D image, when cropped to 1.6x, is a lot closer in actual, realizable IQ to the 7D native image than the pixel calculations would imply.  So overall system resolution (I should have used the term IQ instead of resolution)  is not just about pixel count.   I do think it is astonishing that an 8mp (cropped) image from the 5D3 compares very well with the native 18mp image from the 7D.  I wish I had the reference (sorry) but in another thread this topic was discussed, and examples posted showing this. 

If you look at the better test carried out by Romy, the 7D actually showed noticeably better detail than the 5D2 when distance limited. One guy's test didn't show as much difference, but his results were the outlier.

thanks that is good to know.  now I'm even more anxious to know what the next gen crop bodies will be like.  perhaps more astonishing to me is that the 5D3 pixel density is approximately the same as the 40D.   Clearly, Canon is reluctant to push the pixel density on the FF sensors, but have no such reluctance to do so for the crop bodies.  and now, assuming the H crops are going away, Canon may push more IQ technology towards an upper end 1.6x crop. at least one can hope, which is (last I checked) what this site encourages lol :D

I think it's more been that they've been limited by processing power, since processing only cares about total MP count and not density, than not wanting high MP on FF, I think. 18MP on APS-C or FF requires the same processing power. But 48MP on FF takes a LOT more processing power than 18MP on APS-C (48MP is 18MP APS-C density scaled to FF).
 

canon rumors FORUM

Re: I still don't get the crop debate
« Reply #30 on: April 12, 2012, 12:06:03 AM »

LetTheRightLensIn

  • Canon EF 300mm f/2.8L IS II
  • *******
  • Posts: 3433
    • View Profile
Re: I still don't get the crop debate
« Reply #31 on: April 12, 2012, 12:07:18 AM »
I could be wrong but in terms of cropping a FF sensor, patents may be involved.  Nikon is doing it with its FF sensor, but again I believe patents may be involved here.

That would be the height of absurd patents. How in the world can you patent cropping?? (then again some patents are pretty absurd, but still, this would really take the cake)

I know!  But I have done some patents in the past and cropping on a FF (or some aspect of it) is definitively somthing someone could try to patent, at least to make it more difficult for a competitor to replicate (allbeit not impossible!).

well the new 1 D Cinema does it so it's not been patented (thank god! that might've been a new low for the patent office hah (unless the fact they do it for video somehow makes it magically avoid the stills patent haha))

LetTheRightLensIn

  • Canon EF 300mm f/2.8L IS II
  • *******
  • Posts: 3433
    • View Profile
Re: I still don't get the crop debate
« Reply #32 on: April 12, 2012, 12:08:36 AM »
Why can't the crop guys and FF guys just get along :)? Crop sensors allow manufacturers to sell entry-level DSLR's packed with megapixels and all kinds of bells and whistles for a fraction of the cost of FF bodies. Then users get hooked, and drop loads of cash on lenses and accessories. Then users are committed to a system/brand, and continue to buy equipment within that system. Considering that you can get astoundingly good results with a crop body, and many crop consumers aren't even aware how big (or small) the sensors are in their cameras, why would crop sensors ever go away?

The ff guys talk about IQ
The crop guys talk about reach
The APS-H guys get it in the neck from both  ;D ;D ;D ;D

 ;D

LetTheRightLensIn

  • Canon EF 300mm f/2.8L IS II
  • *******
  • Posts: 3433
    • View Profile
Re: I still don't get the crop debate
« Reply #33 on: April 12, 2012, 12:10:28 AM »
In a related note, I must've missed the white paper on AF-S lenses and why Canon bothered with making the short back focus things at all. I don't see any technical advantage; you get more incident angle of light on the sensor corners resulting in a bit more falloff (w-o adjusting microlenses on the sensor) and it's only slightly less likely to image dust sitting on the AA filter than the longer back focus distance from an EF lens.  Would make more sense to leave the same back focus distance as an EF lens and just position the AA filter a little farther from the sensor to reduce dust imaging. Then microlens positioning would also not have to be a compromise if all lenses used similar back focus distance... ignoring rear group focusing changing that anyway.  Can anyone enlighten me on this aspect of the design decision?  was it just to prevent the N-crowd from adapting Canon glass to their bodies w-o requiring an in-between optic?

i'mnot 100% sure but I think only 1 or maybe 2 of their EF-S actually even really make true helpful use of it at all, I might be wrong on this though, not so certain

Aglet

  • 1D Mark IV
  • ******
  • Posts: 929
    • View Profile
Re: I still don't get the crop debate
« Reply #34 on: April 12, 2012, 01:00:08 AM »
I think it's more been that they've been limited by processing power, since processing only cares about total MP count and not density, than not wanting high MP on FF, I think. 18MP on APS-C or FF requires the same processing power. But 48MP on FF takes a LOT more processing power than 18MP on APS-C (48MP is 18MP APS-C density scaled to FF).

nuther related note, I think processing requirements go up somewhat if people also select in-camera hi-iso NR. Sure can slow down the shooting speed if I accidentally turn that on... clogs the buffer faster anyway.  I reduce in-camera overhead with all processing off, raw only, no jpgs either... unless I need really long bursts at full speed then raw gets turned off and jpg compression to minimum.

if sensor density goes up, not only does the size of the data array increase but the required noise reduction processing going on, even for the raw files, will add a bit more overhead compared to a larger pixeled (lower noise) sensor.  Yet another reason to wish for less sensor noise at all sensitivities.

wickidwombat

  • Canon EF 400mm f/2.8L IS II
  • *******
  • Posts: 4456
    • View Profile
Re: I still don't get the crop debate
« Reply #35 on: April 12, 2012, 01:09:21 AM »
I think it's more been that they've been limited by processing power, since processing only cares about total MP count and not density, than not wanting high MP on FF, I think. 18MP on APS-C or FF requires the same processing power. But 48MP on FF takes a LOT more processing power than 18MP on APS-C (48MP is 18MP APS-C density scaled to FF).

nuther related note, I think processing requirements go up somewhat if people also select in-camera hi-iso NR. Sure can slow down the shooting speed if I accidentally turn that on... clogs the buffer faster anyway.  I reduce in-camera overhead with all processing off, raw only, no jpgs either... unless I need really long bursts at full speed then raw gets turned off and jpg compression to minimum.

if sensor density goes up, not only does the size of the data array increase but the required noise reduction processing going on, even for the raw files, will add a bit more overhead compared to a larger pixeled (lower noise) sensor.  Yet another reason to wish for less sensor noise at all sensitivities.

couldn't agree more, I have absolutely no interest in any in camera processing It would be nice to have 1 option
- Disable all in camera processing so you dont have to individually hunt down and turn off all the rubbish thats on by default.
- all this in camera lens correction blah blah blah just slows it all down more and produces substandard results

an in camera processor is never going to have a hope of competing against proper desktop editing and thats just from a pure processing power available standpoint.
I could be wrong but i'm fairly sure in camera processor are still essentially running on old DOS system architecture.
APS-H Fanboy

Drizzt321

  • 1D X
  • *******
  • Posts: 1668
    • View Profile
    • Aaron Baff Photography
Re: I still don't get the crop debate
« Reply #36 on: April 12, 2012, 02:23:40 AM »
In a related note, I must've missed the white paper on AF-S lenses and why Canon bothered with making the short back focus things at all. I don't see any technical advantage; you get more incident angle of light on the sensor corners resulting in a bit more falloff (w-o adjusting microlenses on the sensor) and it's only slightly less likely to image dust sitting on the AA filter than the longer back focus distance from an EF lens.  Would make more sense to leave the same back focus distance as an EF lens and just position the AA filter a little farther from the sensor to reduce dust imaging. Then microlens positioning would also not have to be a compromise if all lenses used similar back focus distance... ignoring rear group focusing changing that anyway.  Can anyone enlighten me on this aspect of the design decision?  was it just to prevent the N-crowd from adapting Canon glass to their bodies w-o requiring an in-between optic?

i'mnot 100% sure but I think only 1 or maybe 2 of their EF-S actually even really make true helpful use of it at all, I might be wrong on this though, not so certain

Well, not allowing it to mount on a FF body does help some in the lens design & production costs. They don't have to worry about the edges quite as much, since the crop sensor won't necessarily fill up the circle that the lens produces.

Also, being cynical, it lets them charge some users twice. Once for the couple of lenses they buy with the crop camera (after all, EF-S is 'optimized' for their camera!), and second when they go up to FF or realize that they EF-S lenses, by and large, don't have anywhere near the quality of the L lenses and so they go off and buy the L glass.
5D mark 2, 5D mark 3, EF 17-40mm f/4L,  EF 24-105mm f/4L IS USM, EF 135mm f/2L, EF 85mm f/1.8
Film Cameras: Mamiya RB67, RB-50, RB-180-C, RB-90-C, RB-50, Perkeo I folder, Mamiya Six Folder (Pre-WWII model)
http://www.aaronbaff.com

canon rumors FORUM

Re: I still don't get the crop debate
« Reply #36 on: April 12, 2012, 02:23:40 AM »

Ellen Schmidtee

  • 7D
  • *****
  • Posts: 441
    • View Profile
Re: I still don't get the crop debate
« Reply #37 on: April 12, 2012, 02:31:23 AM »
ok, yes I get that in today's market, the crop sensors are less expensive, and that it is cheaper to produce many, smaller sensors (more revenue from the same silicon substrate).  for that reason I don't see the crops going away soon. 

but the advantages of the smaller sensors (reach) are (currently at least) overshadowed by the consequences of pixel density  -- large sensors put more pixels on the image with lower pixel density, which is why the IQ is higher.  captain obvious at your service :-)

The extra reach isn't a result of the smaller sensor, but of the higher pixel density.

As example, There's no difference between taking a photo with a 5Dmk2 & cropping to 40% and taking the photo with a 20D (the rest being equal, including the lens), as 40% of the 5Dmk2's 21.1MP is almost identical to the 20D's 8.25MP.

The benefit of crop factor is in price, both for the body and [up to certain focal lengthes] lenses smaller image circle.

dlleno

  • 6D
  • *****
  • Posts: 599
    • View Profile
Re: I still don't get the crop debate
« Reply #38 on: April 12, 2012, 03:20:18 AM »

yes, what I mean here is that the consequences of pixel density do come into play at normal ISO speeds at the same FOV  when pixel peeping.  This is evidenced by the fact that a 5D image, when cropped to 1.6x, is a lot closer in actual, realizable IQ to the 7D native image than the pixel calculations would imply.  So overall system resolution (I should have used the term IQ instead of resolution)  is not just about pixel count.   I do think it is astonishing that an 8mp (cropped) image from the 5D3 compares very well with the native 18mp image from the 7D.  I wish I had the reference (sorry) but in another thread this topic was discussed, and examples posted showing this. 

If you look at the better test carried out by Romy, the 7D actually showed noticeably better detail than the 5D2 when distance limited. One guy's test didn't show as much difference, but his results were the outlier.

thanks that is good to know.  now I'm even more anxious to know what the next gen crop bodies will be like.  perhaps more astonishing to me is that the 5D3 pixel density is approximately the same as the 40D.   Clearly, Canon is reluctant to push the pixel density on the FF sensors, but have no such reluctance to do so for the crop bodies.  and now, assuming the H crops are going away, Canon may push more IQ technology towards an upper end 1.6x crop. at least one can hope, which is (last I checked) what this site encourages lol :D

I think it's more been that they've been limited by processing power, since processing only cares about total MP count and not density, than not wanting high MP on FF, I think. 18MP on APS-C or FF requires the same processing power. But 48MP on FF takes a LOT more processing power than 18MP on APS-C (48MP is 18MP APS-C density scaled to FF).

true indeed.  Beyond that, there  are noise and ISO compromises that come with high pixel density, although Sony is demonstrating state-of-the-art advances there, in the Nikon D800, and Canon may be behind in that race.  That aside, the 7D really pushed the pixel density envelope to new levels, I'm presuming at the cost of noise and ISO performance, which the market apparently is willing to bear or even drive, as the megapixel wars seem to be most prevalent within markets that don't care as much about those things. I wonder, accepting the demise of "H"bodies, how Canon will please the pro wildlife crowd.   1D4 still fills that niche today,  but going forward wildlifers switching  to 1DX will have to make up that reach factor with glass.  not a bad, revenue-generating strategy.


dlleno

  • 6D
  • *****
  • Posts: 599
    • View Profile
Re: I still don't get the crop debate
« Reply #39 on: April 12, 2012, 03:27:45 AM »
couldn't agree more, I have absolutely no interest in any in camera processing It would be nice to have 1 option
- Disable all in camera processing so you dont have to individually hunt down and turn off all the rubbish thats on by default.
- all this in camera lens correction blah blah blah just slows it all down more and produces substandard results

an in camera processor is never going to have a hope of competing against proper desktop editing and thats just from a pure processing power available standpoint.
I could be wrong but i'm fairly sure in camera processor are still essentially running on old DOS system architecture.

+1 why on earth did in-camera lens correction happen I'll never know.  Unless the target is jpg shooters with inexpensive lenses and no off-camera processing, in which case the need isn't as intense anyway!

dlleno

  • 6D
  • *****
  • Posts: 599
    • View Profile
Re: I still don't get the crop debate
« Reply #40 on: April 12, 2012, 04:23:32 AM »

I like me a good APS-H body! I hope the used 1D4 market takes a dump once the 1Dx comes out. Too bad Canon got rid of the 1.3:1 sensor. It really is a great compromise between the APS-C and FF extremes.

+1!

Quote

I'm on the APS-H wagon too... we must be masichists :P

personally I think a good crop complements a FF very nicely
I just have not been overly thrilled with the 7D sensor when i looked at getting one I decided i'd rather stay with the APS-H.
I am waiting with interest to see what they decide to do with the 7DII if it eventuates or if they kill it off

absolutely right, and many are right behind you.     The 7D is an anomaly to me -- it offers substantial contributions in areas important to wildlifers, but no real game changer in the sensor itself, which appears to have just pushed pixel density to new levels for little benefit.   Yet, if they totally abandon the high performance crop body altogether, then wildlifers are going to have to carry more glass as they move from 1D4 to the 1Dx. 

has their been an announcement such that we are certain Canon is committed to the demise of H bodies?

There appears to be a market need for a high performance crop body;  what I don't get is how (or if) Canon will fill that need if they are abandoning the 1.3.  It seems unlikely to me that we would see a 1.6x body as a worthy successor to the mighty 1D4, but if thats what Canon produces I doubt it will  have a 7 in the name. Canon's next move (or lack of one) in the performance crop body arena will be as newsworthy as the 5D3



 

RLPhoto

  • Canon EF 300mm f/2.8L IS II
  • *******
  • Posts: 3354
  • Gear doesn't matter, Just a Matter of Convenience.
    • View Profile
    • My Portfolio
Re: I still don't get the crop debate
« Reply #41 on: April 12, 2012, 07:17:00 AM »
If you can afford a full frame body and lenses but want the reach of aps-c, just get both. Two bodies, one FF and one APSc makes a good pair and diversify your focal lengths, Especially if your a prime shooter.

Why was the 5D2 and 7D combo do popular? It was because their a great team together.

funkboy

  • 7D
  • *****
  • Posts: 415
  • 6D & a bunch of crazy primes
    • View Profile
Re: I still don't get the crop debate
« Reply #42 on: April 12, 2012, 07:51:53 AM »
Well, here's my €0.02 on the subject from the last major thread on this:

http://www.canonrumors.com/forum/index.php?topic=3295.msg69482#msg69482

Oh, what the heck, I'll cross-post:

Quote
Personally I'd be extremely happy with 10-12 1DX pixels in an APS-C camera with a viewfinder a little better than the 7D (if that's possible, I know it's already 100%/1.0x).

I think the yearning for FF is mostly based on:

  • very low noise floor at high ISO
  • great viewfinder image
  • very shallow DoF at moderate focal lengths

If the first two could be made very close to the 5D in a crop camera, then I think the DoF available at APS-C focal lengths is an acceptable compromise for a whole lot of people.  Digic 5+ will certainly help things out in the noise department...

canon rumors FORUM

Re: I still don't get the crop debate
« Reply #42 on: April 12, 2012, 07:51:53 AM »

Leon

  • Guest
Re: I still don't get the crop debate
« Reply #43 on: April 12, 2012, 08:13:35 AM »
Quote
I'm not a physicist but would it not be possible to produce a sensor that would operate in more than one pixel density mode (this is a Canon forum so don't fault me for missing something about the D800 here...).  I don't mean crop I mean pixel density -- for example, operate the sensor at FF 22mp with all the low light advantages thereunto appertaining, and also at FF 38mp to advantage the situations that the crop bodies depend on -- with favorable light, you get higher resolution when you don't need high-ISO, AND you can crop down to 1.6x for more "reach" and still have a 15mp image that no other natively-cropped body would be able to rival. 

I'm not a physicist but would it not be possible to produce a car that would operate in more than one car length mode? I don't mean glue 2 cars together, I mean car length -- for example, operate the car at 3m length with all the parking advantages thereunto appertaining, and also at 5m length to advantage the situations that the big cars depend on -- with a lot of space you get more people in when you don't need to fit into a small parking spot, AND you can size down to 3m for more "squeeze" and still have a 5m car that no other natively-small car would be able to rival.

"I still don't get the crop debate" - now this doesn't come as much as a surprise to me.

Edit: I know I'm bad, but COME ON.
« Last Edit: April 12, 2012, 08:24:48 AM by Leon »

KeithR

  • Guest
Re: I still don't get the crop debate
« Reply #44 on: April 12, 2012, 08:28:23 AM »
compared to a larger pixeled (lower noise) sensor. 

Larger pixels do not mean lower noise - not now, not then, not ever.

canon rumors FORUM

Re: I still don't get the crop debate
« Reply #44 on: April 12, 2012, 08:28:23 AM »