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10-01-2013, 01:27 AM   #376
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QuoteOriginally posted by Class A Quote
Pardon?

Of course, higher pixel density reduces the chances of moiré occurring.

I'm assuming you wanted to write "sharp enough" rather than "fast enough" because lens speed is not relevant here. But even the sharpest lens has a resolution limit and if you make the pixels small enough, the lens acts as a sufficient low pass filter to avoid moiré completely.

Avoiding moiré completely is tough, but every increase in pixel density helps. That's why the 36MP D800E makes a lot more sense than the 16MP K-5 IIs.
You are right, apart that pixel density on the D800E (full frame) is roughly the same as the K5 (APS-C)

10-01-2013, 02:41 AM   #377
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QuoteOriginally posted by Class A Quote
I'm assuming you wanted to write "sharp enough" rather than "fast enough" because lens speed is not relevant here.
I meant exactly what I wrote. Lens speed is important when diffraction is taken into consideration. A fast lens hits its resolution peak at wider apertures than a slower lens does - and due to this, the probability of Moire appearing goes up.

QuoteOriginally posted by Class A Quote
But even the sharpest lens has a resolution limit and if you make the pixels small enough, the lens acts as a sufficient low pass filter to avoid moiré completely.
Exactly, however to completely eliminate any chances of moire appearing ( with bayer filtered sensors) you would need a resolution upwards of 50Mp on an APS-C sensor.
10-01-2013, 04:42 AM   #378
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QuoteOriginally posted by goubejp Quote
You are right, apart that pixel density on the D800E (full frame) is roughly the same as the K5 (APS-C)
Yes, but with respect to the likelihood of moiré occurring, the total number of MP is relevant, not the pixel density.

This is assuming that you take equivalent images with both cameras. Anything else is an apples to oranges comparison. For instance, if you used the same lens with the same settings on both cameras, then the likelihood of moiré occurring would be pretty much the same (because of the very similar pixel density). But the images would be vastly different (different FOV) and hence are not really comparable.
10-01-2013, 05:45 AM   #379
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QuoteOriginally posted by Digitalis Quote
A fast lens hits its resolution peak at wider apertures than a slower lens does - and due to this, the probability of Moire appearing goes up.
If there are lenses that are faster than others, but reach their resolution peak later then your statement is not correct. Given that there are different optical designs with different peaking and maximum sharpness characteristics, I believe it is possible to find counter examples to your statement.

And if it isn't possible to find such counter examples then the peak would always be defined by resolution hitting the diffraction limit for the respective aperture. Which in turn means you are using a very convoluted way of saying "sharper lens".

So either way, I don't see the point to refer to the maximum aperture of a lens.

The decisive characteristic is how well a lens resolves and how large the f-ratio range is with which it exceeds the sensor resolution.

QuoteOriginally posted by Digitalis Quote
Exactly, however to completely eliminate any chances of moire appearing ( with bayer filtered sensors) you would need a resolution upwards of 50Mp on an APS-C sensor.
I don't think that is nearly enough. See Table 3 of the "Do Sensors “Outresolve” Lenses?" article.

10-02-2013, 05:06 AM   #380
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QuoteOriginally posted by ElJamoquio Quote
The FF F/4 stuff is faster, lighter, and cheaper than the APS-C F/2.8 stuff.
No.
F:4 is slower than F:2.8.
F:2.8 is F:2.8 regardless of format.
F:4 and F:2.8 give different exposure.
10-02-2013, 05:10 AM   #381
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QuoteOriginally posted by IchabodCrane Quote
The #1 reason I can think of to buy a FF DSLR is low light IQ. Is the most important DXOMark measurement the low light ISO (which I think is the max ISO where a DR of 9 can be achieved)? D800E is close to ISO 3000 where a K-5 IIs is ISO 1200+. Better than a stop and a third difference.

D800 is one thing, the 20's something mp FF cameras another issue. I suspect no one can spot the difference in a large print from the K-3 and the D600.
I have repeate this story; a friend has a fine art photo gallery - landscapes. The prints are about a meter sized. He use Canon FF and APS. No customer has even been able to say which is which....
10-02-2013, 05:16 AM   #382
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QuoteOriginally posted by Andi Lo Quote
I assume you mean:
DA 60-250 > Tamron 70-300 VC for a third of the price (slightly worse lens, but not a bad performer, one stop extra DOF at 70mm), or 70-200 /4 VR/IS for the same price (one stop extra DOF and shutter speed).
You don't get extra DOF but less DOF. In addition, the APS lens wil give more DOF, larger maximum magnification( for similar lenses) and larger range of DOF. However, hardly anyone buy long telephoto lenses for its absolute shallowness of DOF. They buy lenses for speed; ie the ability or lack thereof of shooting in lower light with faster shuterspeeds. F:2.8 lens is an F:2.8 lens regardless of format and mm variations in DOF wide open is way down on most photographers list of priorities when making images.
10-02-2013, 05:21 AM   #383
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QuoteOriginally posted by starbase218 Quote
Fullframe does give you some extra possibilities when compared to APS-C: you can create shallower DOF and resolution at the same ISO will be better. But if you want to shoot the same photos you have been shooting with APS-C (including the same DOF), don't expect an upgrade. The IQ will most likely be similar.
Extra posibilities allright but at the expense of arguably more useful possibilities like more speed at smaller package. More DOF at the same exposure or faster shutter speed at the same DOF. Closer focusing distance for similar lenses giving the same angle of view. More maximum DOF for near/far relations, larger maximum magnification etc....
FF is primarily about increase in image quality. Larger forats give for most photographers drawbacks but it might be worth it. I used the 645 for over a decade. It is certainly not as versatile as the APS system but sometimes your shooting style is honed to the format you use.

10-02-2013, 05:39 AM   #384
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35mm wide angle lenses are still wide angle on full frame cameras but not on crop sensor APS-C cameras.
10-02-2013, 05:42 AM - 3 Likes   #385
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QuoteOriginally posted by Cynog Ap Brychan Quote
Having both formats (APS-C and FF), I don't understand people who try to make out that FF is somehow better in every respect. All cameras are a set of compromises, and APS-C has some positives over FF, particularly for macro and telephoto work. Personally, I don't see a move from APS-C to FF as an upgrade, but as a change of format, with its particular advantages and disadvantages.

Very much spot on! I have repeatedly argued that FF isn't necessarily an upgrade from APS but a step sideways; they are different formats.
The confusion have arisen due to the use of the wrong physics; the physics of a DOF (wide open) measuring device where the thinnes of DOF is the only factor at the expense of everyting else. This has little relevance for photography.
Photography is about reducing four dimension into two. If you apply this correct approach you will notice the following:
- There are no true equivalence between formats in real life.
- Whatever eqivalency you prefer is wholly subjective and it will change from photographer to photographer, but more importantly, from image to image.
10-02-2013, 05:52 AM   #386
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QuoteOriginally posted by Pål Jensen Quote
You don't get extra DOF but less DOF. In addition, the APS lens wil give more DOF, larger maximum magnification( for similar lenses) and larger range of DOF. However, hardly anyone buy long telephoto lenses for its absolute shallowness of DOF. They buy lenses for speed; ie the ability or lack thereof of shooting in lower light with faster shuterspeeds. F:2.8 lens is an F:2.8 lens regardless of format and mm variations in DOF wide open is way down on most photographers list of priorities when making images.
Yes, less DOF, meaning more options as you can always stop down. The slower shutter when stopped down is counterbalanced by the one stop gain in ISO, so the speed point is rather moot even though it's a slower lens. FF generally results in more options, at the cost of weight and size. Weight and size might be an issue with many people, but may not be for many, especially when shooting for pay, as the hesitance factor is nonexistent, you have to shoot, it's not a matter of "my gear is too heavy to carry". hence I said that DA limited line is the one that needs to be pushed, as it shows where the APS-C benefit really is.

If you think no one is shooting telephoto wide open, why does 70-200/2.8 lenses even exist (and is arguable the most popular flavor of that FL)? Many people shooting portraits with the 70-200/2.8 shoots alot of their images at 2.8. I disagree that DOF is way down the list of priorities, it is certainly behind composition and light, but in 95% of my shooting it's definitely the highest out of three in the exposure triangle. Isn't that why Av and M is the most popular mode, and not Tv or Sv? I know that's oversimplifying things, but I disagree that DOF is "way down the list"

Like Pal Jensen said it is kind of a sidegrade as you do lose some things like MFD, but in my case anyway, the benefits outweigh the costs.

Equivalency is brought up by FF users because it's a real benefit. As I mentioned in another thread, Tamron 28-75 in FF basically can do the job of any prime from 18-50mm that you use at f/2 in APSC (including 50mm, 35mm and 28mm!) meaning less lens changes and less missed shots. Of course like mentioned, this is all just specs, not taking flare resistance, microcontrast, size, subject shyness due to huge lens, MFD etc etc into account, and therefore maybe a just a sidegrade for your shooting. For mine it was an upgrade.

Last edited by Andi Lo; 10-02-2013 at 06:26 AM.
10-02-2013, 06:05 AM   #387
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From all the pro-FF comments we've been seeing in the multitude of threads, one would have thought that these people frequently find themselves at a very specific spot relative to a very specific subject, saying to themselves "I must take a shot from exactly this spot, using exactly this focal length, and my DOF must be exactly this". I'm not a real photographer, so perhaps my cynicism is misplaced, but I fail to see how there would be so many situations where the above rules must apply so strictly.
10-02-2013, 06:21 AM   #388
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QuoteOriginally posted by bxf Quote
From all the pro-FF comments we've been seeing in the multitude of threads, one would have thought that these people frequently find themselves at a very specific spot relative to a very specific subject, saying to themselves "I must take a shot from exactly this spot, using exactly this focal length, and my DOF must be exactly this". I'm not a real photographer, so perhaps my cynicism is misplaced, but I fail to see how there would be so many situations where the above rules must apply so strictly.
Personally I actually find myself often thinking that. I guess you're saying that a shot can always be taken in many different ways? That is indeed true but options is (almost) always good when you have very limited time and no reshoots, hence why FF, more options. It's like saying 50mm/1.4 is better than the kit zoom lens at 50mm, as it has more options.
10-02-2013, 06:48 AM   #389
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A major relevant, market factor between FF and APS-C is that there is interchangeability of many, many lenses. Given the volume of currently manufactured and legacy glass this tilts the market very much in favour of FF above certain price points regardless of equivalency, angles dancing on the heads of pins arguments.

APS-C and FF share mounts between 4 brands. This is substantially different than the old film and current digital MF eras where different formats had different mounts.

The only thing that matter is how much sensor area one gets at a price point. That is all that matters.
10-02-2013, 07:05 AM   #390
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QuoteOriginally posted by Pål Jensen Quote
I have repeate this story; a friend has a fine art photo gallery - landscapes. The prints are about a meter sized. He use Canon FF and APS. No customer has even been able to say which is which....
At base ISO this is true for M4/3, APS-C, and FF. For people who shoot events in available light and live at ISO 3200+ the differences show up pretty fast.
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