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Author Topic: Valid MF criticism or not?  (Read 62084 times)
Frank Doorhof
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« Reply #340 on: September 14, 2007, 12:20:38 PM »
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With all due respect but that picture is not 3D for me.
It's processed with Lucisart if I can trust my eyes  this filter will give you a semi HDR-hypersharpened look and it will add some 3D like look to the shot.
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BJL
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« Reply #341 on: September 14, 2007, 12:21:55 PM »
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Indeed why would they [Canon] want to go after a market that is so tiny it isn't even a drop on a glowing plate for them from a turn-over perspective?
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Indeed, it seems likely that Canon will only go so far as seeking the highest level of lens and sensor performance that it can achieve without extraordinary new investments such as changing to a larger format and destroying backward compatibility with its current huge 24x36 format assets. Canon has done relatively little to upgrade its lens system; just two lenses at the weakest point of the L range(16-35mmm and 14mm).

That seems to leaves MF with a viable high end niche, based on keeping its sensors and lens designs in larger formats (up to maybe 36x48 or 42x56) ahead of what can be done in a format one half or one third the size. MF just has to look at how LF survived in film.

The smaller scale MF market naturally moves more slowly in technological development (look at AF!), but as sensors approach the physical performance limits of a given sensor and pixel size, gaps in "performance per unit area" will close up, and then two or three times the sensor area will have a natural advantage, for those willing to pay some thousands more for both the larger sensors and the longer, state-of-the-art lenses to go with them.
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Ray
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« Reply #342 on: September 15, 2007, 09:52:18 AM »
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The 1Ds3 is not yet available but comparisons between it and MFDBs have generated so much hot air and b/s, one wonders what will eventuate when the camera is released. Will the sparks really start flying? Maybe not. Perhaps bull shit and hot air appear in inverse proportion to the facts.

It always amazes me when such issues as which is bettter than which arise, that some people do their best to massage an image to its best advantage to create an impression that massaged A is better than unmassaged B.

Such lack of objectivity is astounding.

Frank Doorhof's crop of an amazing eye is a good example of what I'm talking about. The pores of the skin under the eye appear out of focus, yet the whole of the eye itself is remarkably sharp. One's first impresssion is, whatever lens was used it would have been at a wide aperture.

But we learn from Frank that this was not the case. The lens used was 120mm at f10. Frank used 'smart sharpening' to sharpen the eye but not the skin pores. Perhaps he even blurred the pores. Perhaps what he really did is a trade secret.

[attachment=3247:attachment]

When you are trying to get to the truth of the matter, such an approach does not help.
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Frank Doorhof
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« Reply #343 on: September 15, 2007, 10:08:09 AM »
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Wrong my friend, I blurred NOTHING, welcome to DOF of a MF system
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Ray
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« Reply #344 on: September 15, 2007, 10:21:28 AM »
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Wrong my friend, I blurred NOTHING, welcome to DOF of a MF system
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Frank,
But you used f10 and selective sharpening, or 'smart' sharpening. F10 is about the limit on any lens before diffraction rears its ugly head. At f10 the pores should be as sharp as the eye.
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juicy
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« Reply #345 on: September 15, 2007, 10:45:40 AM »
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Hi!

To my eyes the upper eye-lashes and brows are the part that is in focus in Frank's eye-picture, lower lashes are not and the skin pores are even more oof. Nothing un-natural there. 120mm lense has a very shallow dof at close distance. Skin over the eye-brow has very sharp texture.  

Cheers
J
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Ray
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« Reply #346 on: September 15, 2007, 11:14:40 AM »
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120mm lense has a very shallow dof at close distance. Skin over the eye-brow has very sharp texture.  
[a href=\"index.php?act=findpost&pid=139574\"][{POST_SNAPBACK}][/a]

This shot is not at a particularly close distance. It's equivalent to a 35mm shot of a full face portrait with 85mm lens at around f7.

Now, if someone can keep this thread in mind and, in a couple of month's time when the 1Ds3 is released, take a similar shot with the 85/1.2 at f7 to f8 , we might have something real to talk about.
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juicy
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« Reply #347 on: September 15, 2007, 12:51:34 PM »
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Hi Ray!

I appreciate your quest for the truth and your analytical approach. It's correct that the really valid comparison will be made in the same shoot with the both cameras, otherwise the comparison will be somewhat arbitrary. However I think we don't need to wait for the 1Ds3 to be able to say something about the dof in the eye-shot.

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This shot is not at a particularly close distance.

Frank might tell us the shooting distance but for me it seems it has been taken at a distance of less than 1m (if the original picture in post 172 has not been dramatically cropped), maybe something like 80cm. Also, to see the aprox dof in a similar Canon shot we don't need the 1Ds3, just the 85mm lens (which I don't have) and any FF Canon unless we want to compare the shots pixel by pixel. The overal feel will be seen in your 5D in case you have the 85mm.

Comparing the eye-shot with my own experiences with 100mm Canon in both FF- and crop-bodies using different f-stops and shooting-distances I don't doubt the dof in Frank's picture at all.

Cheers,
J
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D White
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« Reply #348 on: September 15, 2007, 03:52:21 PM »
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I do not get this endless debate about MF verses Canon and the constant negative comments to Canon lenses. They are two different formats and do different things, as it has always been. As always, if you want speed of handling, wider lens range, faster apertures, easier backpacking, the most responsive AF systems, etc then one picks a 35mm based system. If squeezing out maximum quality for larger reproduction needs is your requirement then you will put up with the limitations, cost, slower handling, generally bulkier nature of larger formats. There is nothing new here.

As image capture is now a function of proprietary electronics rather than film, the traditional gap may ebb and flow over time. What may have an advantage today may be less so tomorrow.

My one and only digital camera is a DsII with a DsIII on order. The extensive L series lens collection I have has never been better and is constantly evolving to new levels with new introductions. I get so much more detail now, with much greater ease, than I did hauling my 50lbs of Blad V-series around with 7 lenses and Velvia film. I would not consider a MF back for my current Blad system given the considerable chromatic aberrations these outdated lenses deliver. The 40mm CF can be a dog and the 500 CF "APO" is definitely a dog. Only the 250 super-achromat gives a clean aberration free result. if if I can see all these faults so clearly on film, I can only imagine how bad it would be on digital.

Unless the new H-series Blad, Mamiya, Contax, etc and vastly better than these classic V-series lenses, I just do not get it. I only see this MF thing working really well on a technical camera with process quality lenses.
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Dr D White DDS BSc
Ray
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« Reply #349 on: September 16, 2007, 03:18:33 AM »
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I do not get this endless debate about MF verses Canon and the constant negative comments to Canon lenses. They are two different formats and do different things, as it has always been. As always, if you want speed of handling, wider lens range, faster apertures, easier backpacking, the most responsive AF systems, etc then one picks a 35mm based system. If squeezing out maximum quality for larger reproduction needs is your requirement then you will put up with the limitations, cost, slower handling, generally bulkier nature of larger formats. There is nothing new here.
[a href=\"index.php?act=findpost&pid=139627\"][{POST_SNAPBACK}][/a]

I'm no expert on MF gear, but as I recall a few years ago the top of the range MFDBs were 16mp with sensors around the size of 35mm. That was well before the 16.7mp 1Ds2 was available.

We now have an interesting scenario whereby the soon to be released 1Ds3 will have the same pixel count as the lower end, but still more expensive, MFDBs, so it's quite understandable that people want to know what they are getting for the extra money.... an elusive sense of extra 3-dimensionality that the 1Ds3 cannot match?

When Nikon produced the 12mp D2x, about as different in format to the Canon 1Ds as the 1Ds3 is to a Leaf 22mp MFDB, I don't recall Canon devotees claiming the larger sensor of the 1Ds produced a greater sense of 3-dimensionality.
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Ray
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« Reply #350 on: September 16, 2007, 03:46:20 AM »
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Also, to see the aprox dof in a similar Canon shot we don't need the 1Ds3, just the 85mm lens (which I don't have) and any FF Canon unless we want to compare the shots pixel by pixel. The overal feel will be seen in your 5D in case you have the 85mm.

Comparing the eye-shot with my own experiences with 100mm Canon in both FF- and crop-bodies using different f-stops and shooting-distances I don't doubt the dof in Frank's picture at all.

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I don't doubt the DoF either. With the same lighting and model, same accurate focussing, same 'smart' sharpening, same color balance etc, I would be very surprised if the 1Ds3 with 85mm lens at f7.1 would not produce equally impressive results.

I don't believe one could get an idea of the differences by comparing a 12.8mp 5D with a 22mp MFDB. The resolution differences are simply too great. If one were to compare a 5D with a 1Ds3, same close-up of a face, using the same lens, say 85/1.2 at f7.1, one would expect the 1Ds3 shot to be sharper at the plane of focus, but not sharper away from the plane of focus. In other words, the 1Ds3 shot would exhibit a slightly shallower DoF despite use of the same lens at the same f stop and the same distance to subject.

The difference might be subtle but possibly sufficient to produce that sense of greater 3-dimensionality.
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jing q
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« Reply #351 on: September 16, 2007, 09:25:58 AM »
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I don't doubt the DoF either. With the same lighting and model, same accurate focussing, same 'smart' sharpening, same color balance etc, I would be very surprised if the 1Ds3 with 85mm lens at f7.1 would not produce equally impressive results.

I don't believe one could get an idea of the differences by comparing a 12.8mp 5D with a 22mp MFDB. The resolution differences are simply too great. If one were to compare a 5D with a 1Ds3, same close-up of a face, using the same lens, say 85/1.2 at f7.1, one would expect the 1Ds3 shot to be sharper at the plane of focus, but not sharper away from the plane of focus. In other words, the 1Ds3 shot would exhibit a slightly shallower DoF despite use of the same lens at the same f stop and the same distance to subject.

The difference might be subtle but possibly sufficient to produce that sense of greater 3-dimensionality.
[a href=\"index.php?act=findpost&pid=139711\"][{POST_SNAPBACK}][/a]

just thought I'd post an image from a very old shoot using a kodak pro back (16 megapixels) on a mamiya 645AF (girl's face)

This image was then cropped down by a quarter so it's about 12 megapixels.
Up till today I still feel that the image has a very different dimensional feel to it compared to anything I can produce with my 1ds MkII.
However I sold off the Kodak back because it was just too inconvenient to try and focus with square crop

I've attached a mkii image also, as much as I like the image I still think there would be a very different feel with MF (guy's face)
[attachment=3266:attachment][attachment=3266:attachment]
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D White
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Don White


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« Reply #352 on: September 16, 2007, 11:05:04 AM »
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The different feel in dimensionality, in my opinion, is the result of lens focal length. There is a difference in feel to a portrait on the Blad with say a 120/150/180 focal length, at any given aperture, than with a 35mm based system and a similar range of focal lengths. You can never get the exact same combination of perspective and selective focus to a portrait--although I am sure the technically savvy guys can quote equivalent combinations that would match results between the two formats.

It is for this one reason that I may some day add a MF back, for formal portrait sittings.
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Dr D White DDS BSc
Frank Doorhof
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« Reply #353 on: September 16, 2007, 12:08:21 PM »
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Hi,
The distance was app 1 mtr from the model.
AGAIN NO BLURRING, only a little bit of smart sharpen GLOBAL.

Diffraction on f10 ??
I have shot my 5D on f16 and higher numerous times because I had no choice, and can say that anything above and on f16 was noticably softer that f8-f11 which seems to be the sweet spot for the 5D.

With the Leaf I have shot several shots on f11 and f22 and cannot say I see ANY form of diffraction, or at least not as noticable as with the 5D.

Do you have experience with MF or are you just guessing (with all due respect).
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Ray
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« Reply #354 on: September 17, 2007, 02:28:32 AM »
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Do you have experience with MF or are you just guessing (with all due respect).
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Hi Frank,
I have a couple of MF film cameras, the Mamiya RB67 and the Fuji fixed lens 6x9, GSW69II (or some name like that). I also have a Nikon 8000ED MF scanner.

Unfortunately, I've been sort of spoiled by the sheer convenience of digital cameras and I never used those MF film cameras nearly as much as I thought I would have at the time I bought them. Another waste of money I'm afraid.

As regards diffraction at f10, it really depends on the quality of the lens. The higher the quality (or resolving power) of the lens, the wider the aperture at which diffraction becomes noticeable. Most 35mm lenses seem to peak at f5.6 to f8. With a medium quality zoom like the Canon 24-105 IS, I find there's no significant difference in resolution between f8 and f16 on the 5D, but the very slight softness at f16 is noticeable. At f22, it's pretty obvious.

I'm guessing that a very good MF lens used with a high pixel density sensor such as the Leaf 22mp (with pixel pitch hardly greater than that of the 5D) would begin to reveal the effects of diffraction at f stops numerically greater than f10.

I also doubt that it's possible to manufacture a lens that is as sharp at f10 as the Canon 85/1.2 is at f7.1. This is why I think a comparison between the Leaf 22mp with 120mm lens at f10 and the 1Ds3 with 85mm lens at f7.1, would be ideal.

The 1Ds3 needs a sharper lens because of it's higher pixel density. If you use a lens with the MFDB that is as sharp or sharper than the 35mm equivalent, then there's no contest. The larger sensor, despite equal pixel count, will produce superior results, at least at base ISO and maybe ISO 200.
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Frank Doorhof
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« Reply #355 on: September 17, 2007, 03:39:47 AM »
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The problem with diffraction is that you can actually never give a fixed number, it all depends on the resolution of the lens vs the pixelsize (distance) of the sensor, when lines overlap we have diffraction (in short).

I can honestly say that with all lenses I have tested now with the Leaf and Mamiya AFD/II I cannot see diffraction of f16 which I normally use in the studio alot for my normal work, for my free work I love to work with a very shallow DOF and use f10 or f8, when looking at 1:1 crops of the eyes all are about equal sharp.
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BJL
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« Reply #356 on: September 17, 2007, 11:31:28 AM »
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I can honestly say that with all lenses I have tested now with the Leaf and Mamiya AFD/II I cannot see diffraction of f16 ...
[a href=\"index.php?act=findpost&pid=139899\"][{POST_SNAPBACK}][/a]
That is with a 22MP Leaf back, and so 9 micron pixel pitch, correct?
If so, your observation further confirms a trend in real world observations on diffraction effects with digital cameras: the effect is not noticeable until aperture ratio is about twice the pixel pitch in microns or more, so around f/18 in this case. (Another example: f/11 for the Nikon D2X and its 5.5 micron pixels, according to Thom Hogan.)

This is about half the aperture diameter or two stops higher than the hard-line theoretical claims bases on limiting Airy disc diameter (diffraction spot size) to about the same as pixel spacing.
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Frank Doorhof
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« Reply #357 on: September 17, 2007, 11:46:24 AM »
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With the Aptus 22 indeed.
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