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01-10-2011, 07:50 PM   #16
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QuoteOriginally posted by Smolk Quote
Was he a Langlaufer?
Ja, wohl der beste nordische Skifahrer. oder Langläufer wie sie sagen, in der Geschichte.

I find few prominent athletes I can admire as I get older, he is an exception.

So, back to the 645D. Chicagonature: the 45-85 is very good. I have a 35mm A, which is great with film, appears to be not so good on the 645D, although I need to test it more. Based on what I read about the 35mm FA, it should be fine. A number of Canon shooters were using it with a Zoerk adapter.

01-11-2011, 03:01 PM   #17
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Has anyone tried the 35mm F3.5 FA on the 645D. This lens is suppose to be really good . I have looked for it multiple times and always come up empty
01-11-2011, 05:33 PM   #18
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Shuttershane
I don't know if you are in the USA, but when I purchased my 645D from acephoto.net, an one of the few authorized 645D dealers in the states, they had a "new 35mm FA" for sale for $1300.00
I almost purchased it, but when they did some test shots for me outside of the store, I was not impressed so I passed on it, though looks like someone else purchased it.
IMHO i don't think this was a good copy of the lens.

Thats the whole problem, if you are lucky enough to find a new FA lens which are all now at least been sitting on someones shelve for over 1.5 years, the odds of getting a good copy are slim. I talked to Pentax USA today and the tech guy said 2 out 10 lens they tested in house were good. that's it. Not very good. Who knows what the future holds,
Oh yeah his excuse for such a small good percentage was none of these lenses were ever designed for digital, whatever that means, except the new 55mm SWD which has been getting poor reviews well at least if you are a landscape shooter like myself, Diglloyd had multiple copies of the 55mm lens all with the same problem.

I don't know what to think at this point.

Steven
01-11-2011, 06:53 PM   #19
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Steven (kuau), what is it that you did not like about the 35mm lens? Was is sharpness or resolution or what?

For Everyone,

Can anyone explain some of the reasons why a lens is better with film than it is with a digital sensor? I understand that shiny sensors cause light to bounce around with the lens, but I'm talking more about sharpness and resolution. Also, remember that the 645 lenses are true 6x4.5 lens, whereas the 645D sensor is smaller and is able to take advantage of the lenses sweet spot. So, what's up with that?

01-11-2011, 07:54 PM   #20
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I am wondering the same thing. I would really like to see someone go out and shoot images with the same lens on the 645d and a film body and compare them. My guess is if the scanned film is at the same resolution it should show the same issues. Maybe the films grain is making the sharpness seems better, if that's not it then i have no clue.
01-11-2011, 08:35 PM   #21
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QuoteOriginally posted by chicagonature Quote
Can anyone explain some of the reasons why a lens is better with film than it is with a digital sensor?
My guess: with film, if you were relatively close in focusing, you were "close enough". With digital, if you miss a bit, you can pixel peep and see how badly you missed. Same with lenses that aren't quite as sharp overall as they can be..with film, it's close enough. Some of the old time film images that were highly respected (e.g., some of the Avedon work, black&whites, etc), I though weren't that sharp...
01-11-2011, 11:45 PM   #22
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QuoteOriginally posted by Shuttershane Quote
I am wondering the same thing. I would really like to see someone go out and shoot images with the same lens on the 645d and a film body and compare them. My guess is if the scanned film is at the same resolution it should show the same issues. Maybe the films grain is making the sharpness seems better, if that's not it then i have no clue.

I have read that the problem with film-age wide angle lenses on digital cameras is the low angle of approach of light near the image borders. The borders between receptors tend to scatter the light. Wide angle lenses designed for digital cameras reduce this angle, either by moving the rear element away from the sensor or increasing its diameter.
01-14-2011, 07:18 AM   #23
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QuoteOriginally posted by civiletti Quote
I have read that the problem with film-age wide angle lenses on digital cameras is the low angle of approach of light near the image borders. The borders between receptors tend to scatter the light. Wide angle lenses designed for digital cameras reduce this angle, either by moving the rear element away from the sensor or increasing its diameter.
I also heard that the coating they use for new digital lenses helps as well. I wonder if a good UV filter with the so called "digital" coating would help this.

01-14-2011, 08:38 AM   #24
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An 35mm/f3.5 A example at f/14: Look Good

I posted about the 33-55mm zoom. Forgot actually there was a good example off the A version of the 35mm/f3.5 (the A and the FA have different optical designs) in this Japanese test:

Google Translate

It is reasonably sharp all the way to the corners.
Attached Images
   

Last edited by leping; 01-14-2011 at 08:44 AM.
01-14-2011, 11:03 AM   #25
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QuoteOriginally posted by chicagonature Quote
For Everyone,

Can anyone explain some of the reasons why a lens is better with film than it is with a digital sensor? I understand that shiny sensors cause light to bounce around with the lens, but I'm talking more about sharpness and resolution. Also, remember that the 645 lenses are true 6x4.5 lens, whereas the 645D sensor is smaller and is able to take advantage of the lenses sweet spot. So, what's up with that?
Mike - there are *many* factors at play in digital versus film, and that's quite a topic to go on about in and of itself. I'm not a real techno guru but I'll give it a go for starters ...

Technical hooey - A few factors you may want to read about concerning CCD/CMOS sensors vs. film, along with my unqualified explanation the way I understand it.

- Bayer filtering - RGB is sensed in 2x2 horiz. arrays (1R,1B,2G) <except Foveon sensors>; whereas film is 3 vertical layers/substrates. The upshot to this is photons exciting a CCD may or may not hit the right color photodiode on the array (again due to many reasons like channel width, microlenses, etc.), note the pixel size is quite small (e.g. 5 micron). In film however, where the grain size is ~10 microns, generally speaking a single photon of a particular wavelength nearly always will strike the correct color layer (as the grains are vertically aligned).

- CCD microlenses - these are small lenses atop each pixel to increase the amount of photons hitting the sensor buckets. Suffice it to say they don't always target the right photodiode for a given wavelength.

- Analog lens designs are meant to gather light of all wavelengths and deliver them to the film plane at a wide range of angular incidence, whereas CCD/CMOS sensors (due to the walls surrounding the buckets) can't tolerate extreme (high) angles of incidence (more like they want it perpendicular). The end result is the CCD/CMOS sensor gets less photons to eat; hence the Signal to Noise (SNR) ratio is lower than would be for a given 10 micron section of film (if using an analog lens).

- Because of their smaller size (format and "grain" or pixel size) and their nature CCD/CMOS sensors don't react / fare the same as film in regards to the effective aperture of the lens. Essentially there's a lot of stuff getting bounced around/absorbed, hence F22 on film may look great - on digital it will result in really soft images.

There's a ton of resources on the web about this btw.

On the more practical advice side, I've worked as an amateur with MF for about 20 years. I gave up film about 9 years ago. I currently have a mixed camera arsenal of Mamiya RZ (every lens), PhaseOne 645 (a wide range of mostly Mamiya lenses), Contax 645 kit (except the 350 APO), Nikon kit, and even odd looking technical cameras. MF digital capture is on Phase P65+ and Leaf. All of that in search of replacing my fond film days - and I've never achieved that "look" or romance (but hey I'm still trying).

For the MF lenses I've come to a few general but very subjective conclusions about my some odd 50 analog MF lenses on digital using Kodak/Phase/Leaf:

- Most *MF* lenses (except Zeiss) were mass produced with mediocre standards in the last 30 years (pre digital). Thus you get a huge variation in the quality for a given lens.
- Bigger glass is always sharper and more contrasty (e.g. I'd prefer an RZ lens any day over 645) - I think this is because the exit pupil is bigger and the sensor gets to eat more perpendicular photons (take a look at a 67 lense at f11 vs. a 645).
- Primes are always sharper
- Faster isn't better unless you're in low available light.
- Zooms (including Zeiss) - plainly suck (but they're convenient!)
- Don't go wide open unless its night time and your shooting bums.
- Don't ever do anything tighter than f11 unless its a pinhole
- AF on any MF camera (up to and including the 645D and Phase/Mamiya 645DF, and Leica S2 or Hassleblahs) blows chunks, even my D1 of 11 years ago had much better AF.

Having stated the above it might sound as if I'm saying analog lenses used with digital backs aren't useful for good photography. I think the issue is I (we?) tend to over-analyze the digital output whereas I didn't have a 250x loupe handy 10 years ago to know the difference.

Sure these lenses have shortcomings on digital - and in 5 years time a new breed of Pentax digital lenses will likely replace the current AF analog line available now - but in the meantime we have to make do with what we have. That's not true for some other pricey makes with Zeiss or Schneider glass but the entry point for those systems is in the $50K range. So we have to adapt and innovate our techniques unless we're ready to spend that kind of cash.

Here's an example for you how to adapt your analog lenses - in your original post you stated you shoot mostly f/16~f/22 deep view landscapes with closest focus in the range of a couple of feet to the horizon. You ain't gonna do that sharply in digital at f/16 or f/22. So .... why not shoot (digital) focus bracketed at f8 (or the sweet spot for a particular lens) with maximum sharpness and then stack the frames in post processing ? The resulting print would be sharper, deeper, and more contrasty than you could ever achieve at f16 or 22 on a single frame of film (or digital). Note you can do this with scanned film as well (ain't that convenient thou). There's a famous landscape photographer out there using that technique now on a P65+ with an 8x10 Deardorff for sale btw, and I bet he didn't look twice (nor knew how to do so initially) at a lens resolution test or endless frames of brick walls.

Sorry for the long post - its cold out tonight and I'm too awake anticipating my 645D arriving tomorrow
01-14-2011, 12:21 PM   #26
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QuoteOriginally posted by VoltMan Quote
... So .... why not shoot (digital) focus bracketed at f8 (or the sweet spot for a particular lens) with maximum sharpness and then stack the frames in post processing ? The resulting print would be sharper, deeper, and more contrasty than you could ever achieve at f16 or 22 on a single frame of film (or digital). Note you can do this with scanned film as well (ain't that convenient thou). There's a famous landscape photographer out there using that technique now on a P65+ with an 8x10 Deardorff for sale btw, and I bet he didn't look twice (nor knew how to do so initially) at a lens resolution test or endless frames of brick walls.
I agree 100% pixel peeping is a waste of life, but unlike exposure braketing (HDR, etc.) there are simple, basic, and fundamental problems with the so called "focusing bracketing", the big reason softwares trying to accomplish this have never passed consumer product level, unless your shot subjects strictly on a 2D oblique angled plane.

The basic obstacle is: when you focused on the background, any foreground subject (say a tall grass) obstructing portion of the background will be diffused into a larger fussy region, the look of which we call bokeh, occulting the background details you need to obtain. The results is a fussy "halo" around the foreground subjects for which there is no way to recover, and the extent is determined by how out-of-focus the foreground is.

Try this on a near - far scene today, something like a bottle of wine nearby in front of pictures on the wall far away and see what I am saying. You will never get details of the picture nearing edges of the bottle.

Last edited by leping; 01-14-2011 at 12:26 PM.
01-14-2011, 12:55 PM   #27
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QuoteOriginally posted by leping Quote
I agree 100% pixel peeping is a waste of life, but unlike exposure braketing (HDR, etc.) there are simple, basic, and fundamental problems with the so called "focusing bracketing", the big reason softwares trying to accomplish this have never passed consumer product level, unless your shot subjects strictly on a 2D oblique angled plane.

The basic obstacle is: when you focused on the background, any foreground subject (say a tall grass) obstructing portion of the background will be diffused into a larger fussy region, the look of which we call bokeh, occulting the background details you need to obtain. The results is a fussy "halo" around the foreground subjects for which there is no way to recover, and the extent is determined by how out-of-focus the foreground is.

Try this on a near - far scene today, something like a bottle of wine nearby in front of pictures on the wall far away and see what I am saying. You will never get details of the picture nearing edges of the bottle.
It may not work in all extremes perhaps but works well in a lot of cases depending on which tool you use. For example see AllFocus EDF Image Gallery and look at the bottom example of a near-far non macro shot as you described above - I admit there has to be enough contrast and sufficient stack spacing however its still a useable approach especially if using masks within PS.

Note I mostly stack in micro/macro work however.
01-14-2011, 01:30 PM   #28
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QuoteOriginally posted by VoltMan Quote
It may not work in all extremes perhaps but works well in a lot of cases depending on which tool you use. For example see AllFocus EDF Image Gallery and look at the bottom example of a near-far non macro shot as you described above - I admit there has to be enough contrast and sufficient stack spacing however its still a useable approach especially if using masks within PS.

Note I mostly stack in micro/macro work however.
Yes I tried the software and actually had communication with them. If you are not looking at 1000 pixel tall JPEGs you will see the halo effects. They also managed to avoid real meaningful details around the edges of the pole. The problem is a simple matter of fact, and no smart software one day can recover (unless they move to the side and take another shot avoid the pole) - you can try to simulate but never create real data from nowhere. Weather the results are acceptable depending on the applications, as well as the standard of acceptance: many listen to 128kb MP3 music everyday and be very happy.

Last edited by leping; 01-14-2011 at 01:40 PM.
01-14-2011, 01:53 PM   #29
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QuoteOriginally posted by leping Quote
Yes I tried the software and actually had communication with them. If you are not looking at 1000 pixel tall JPEGs you will see the halo effects. It is a simple fact and no smart software one day can recover (unless they move to the side and take another shot avoid the pole). Weather it is acceptable depending on the applications and the standard of acceptance: many can listen to 128kb MP3 music and be very happy.
Sorry - was just using that as an example for the scenario you gave. Try Helicon Focus in 64 bit (I use Mac). Its not cheap (about $250) but can stack 60mp from my P65+ all day. The important bit is to plan the shot, stack focal distance, and intermediate stages. If you stack it all in one pass you'll wind up with halos and artifacts. Otherwise layer it in PS and use masks. Granted its quite a bit of work, but the results are outstanding. Again I only do micro/macro but know quite a few commercial guys using it in architectural work.

When the 645D arrives I'll be able to roam around and do some trials
01-14-2011, 06:12 PM   #30
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QuoteOriginally posted by leping Quote
I posted about the 33-55mm zoom. Forgot actually there was a good example off the A version of the 35mm/f3.5 (the A and the FA have different optical designs) in this Japanese test:

Google Translate

It is reasonably sharp all the way to the corners.
This image looks quite good to me. I downloaded the full res (44mb) image. I have been hoping to pick up a 35mm A or FA lens (if I can ever find one), and would like to see more shots with this lens on the 645D.

Gary
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