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01-12-2012, 07:12 AM   #91
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QuoteOriginally posted by drugal Quote
Isn't the EV bar backwards too?

I think this whole thread was caused by the OP hijacking another thread and then getting banned from it. He's now banned from his own thread it seems.

Personally I can totally live with full frame, but when people say that anything shot on APS-C is a snapshot (like the OP said in the other thread) ... it sorta gets my dander up. I've seen pieces of art come from APS-C cameras with great composition, wonderful lighting, and emotion generating impact. I'm VERY happy with my K-5 and I was also pleased with my old K-x, so I want to defend them. Sorta silly, really
I'm with you (and getting banned from your own thread has to be a record )

I've seen pieces of art shot with plastic fantastic lomo's for that matter. One of my best selling prints when I've done shows has been a multi exposure on a holga

01-12-2012, 01:23 PM   #92
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I'd agree that a Pentax FF camera would tick the UI and aesthetic practicalities boxes. Definitely worth waiting for - there just has to be DFA replacements for the DA12-24 and DA 15 Limited at least.
01-12-2012, 01:26 PM   #93
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A D-FA 12-24 F4 would be sick lovely. Especially if it is still sharp corner to corner like the DA 12-24 is on the APS-C sensor.
01-12-2012, 01:37 PM   #94
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QuoteOriginally posted by JinDesu Quote
A D-FA 12-24 F4 would be sick lovely. Especially if it is still sharp corner to corner like the DA 12-24 is on the APS-C sensor.
it will be a huge heavy monster even at F4. the sigma variable aperture 12-24 which is FF is a monster @ 600 grams versus the 430 grams the apsc Pentax is.
If you want the FOV of the Pentax they could build a 20-35 f4.0 which would be half the weight (see FA 20-35 f4.0), and likely could do it for less than the DA 12-24

the Nikon 14-24 2.8 (which is the closest made to your thought) weighs a massive Kilogram (2.2Lbs) but is aspherical and fast and damn pricey at $1800 bucks. even with a small size gain and discount for f4.0 glass this would still probably weigh in at 800 grams and cost $1500 or so.

A realistic expectation would be a 16-35 f4 at $1300 or so and about 700 grams (based on the Nikon size cost)

01-12-2012, 03:05 PM   #95
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QuoteOriginally posted by jsherman999 Quote
Anyone ever get growled at by a Chihuahua?




It's hilarious!

.
Not when it's blown up to that level.
01-12-2012, 03:19 PM   #96
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QuoteOriginally posted by RioRico Quote
Actually FF frames are 2x the area of FF frames. (The diagonal is 1.5x.) So APS-C yield is 2x that of FF yield, before throwing out the bad chips, which skews the balance of APS-C to more like 3x.


That's incomplete. It should be, "Yo momma wears combat boots -- THREE of'em!"
___________________________________________________

At the risk of feeding the troll, I'll say this:

OP;
I can take my Kodak Monitor 6x9 folder with a 105/3.5 lens and make a wide-open exposure. I can then insert a 645 mask and make another exposure. I can replace the mask with a 36x24mm FF mask and shoot again. Replace that with a 24x18 HF (half-frame) mask (close enough to APS-C) and shoot again. Subject doesn't change. Lens doesn't change. Perspective doesn't change. DOF doesn't change. What changes is the AOV, the amount of the projected image that the film captures.

You can see the same thing in-person. Cut a picture from a magazine. Draw a 9x6cm rectangle in it. Inside that, draw a 60x45mm rectangle. Inside that, draw a 36x24mm rectangle. Inside that, draw a 24x18mm rectangle. Picture doesn't change. Perspective doesn't change. DOF doesn't change. What changes is the AOV, the amount of the printed image in the rectangles.

That is exactly what happens when FF and APS-C sensors of the same density see a projected image -- the smaller sensor chops-off the image edges. As-is, most FF sensors are NOT of the same density -- they're lower density. Cut in half an image from an 18mpx FF sensor and the resolution is much lower than an image from a 15mpx APS-C camera. A 30mpx FF cam would be needed to match the resolution of my K20D.

You really do need to gain some education and experience. You're making a fool of yourself.
And the reason there IS a difference is because we then enlarge the output to a standard set of sizes. The only reason a 300mm lens on FF is a 450mm on APS-C is because we enlarge the image to an output the same size (ie A4 or 8x10 etc). This enlargement obviously is more demanding on lenses as it has an increased magnification of any aberrations and is highlighting the perspective inherent in that lens at it's center. As pointed out earlier, you'd have to use a different lens to match perspective and DOF for each format. The results should look the same after that if sensor resolution is the same. But it is definitely harder to produce shorter/faster lenses so perhaps FF has a better chance of a good result.
01-12-2012, 03:40 PM   #97
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QuoteOriginally posted by Class A Quote
Different formats do not imply different looks as long as the change in AOV (cropping reduces AOV) and sharpness/DOF (smaller formats need more enlargement to achieve the same output size) are compensated by using equivalent lenses and equivalent camera settings.

I recommend the "Eqiuvalence" essay by Joseph James for the theory.

In practice, some crop format lenses do not exist so some FF images cannot be reproduced on APS-C. The smaller format is also more demanding on lens sharpness and AF accuracy (because of the higher enlargement factor). On FF, one typically sees more lens vignetting. Various implementation details (e.g., micro lenses) may further contribute to a different FF look.

So in theory crop formats are not disadvantaged per se, but in practice some differences do exist. I agree that bigger formats have their appeal but it certainly is no B&W situation as in "cheap snapshot" vs "pleasing photograph".
I just posted a lame version of your post and wish I'd read this far before doing so. Cheers.
01-12-2012, 03:48 PM   #98
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QuoteOriginally posted by jsherman999 Quote
John, as you can imagine those are all very close to what FF could bring in the 'normal' range, because you're using some very fast, wide-normal lenses there. The 28mm f/2, 40mm f/1.4, and 35mm f/1.4 are not lenses you see used very often.

Shooting them wide-open on aps-c would be duplicated by (about):

28mm f/2 on aps-c ==> 42mm f/3.2 on FF (now you know why the 43ltd would be the first lens I'd buy for the K-1!)
35mm f/1.4 on aps-c ==> 50mm f/2.3 on FF
40mm f/1.4 on aps-c ==> 60mm f/2.3 on FF

The lenses on the left are probably going to be more exotic & hard to find than the ones on the right, and larger and probably more expensive (if they were AF.) Also, at f/3.5, f/2.3, etc, the lenses used on FF will be stopped down one or two to achieve the same look - and probably sharper on the plane of focus as a result, showing a bit less CA, etc.

Now, assuming those are FF-capable lenses, think of the fun you would have shooting them on FF!

28mm f/2 on FF ==> 18mm f/1.2 on aps-c
35mm f/1.4 on FF ==> 23mm f/0.95 on aps-c
40mm f/1.4 on FF ==> 27mm f/0.95 on aps-c

(Anyway, congrats on getting and shooting those cool lenses to great effect. Really liked the apple shot especially)

Does this mean that my FA*300 F/4.5 is really an 450 F/6 (?) on APS-C? [insert obligatory smiley better late than never I guess ]


Last edited by bossa; 01-12-2012 at 09:51 PM. Reason: My question was tongue in cheek..
01-12-2012, 05:30 PM   #99
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QuoteOriginally posted by bossa Quote
And the reason there IS a difference is because we then enlarge the output to a standard set of sizes.
And that's presentation, not photography -- part of the picture-making process, but not controllable from the camera, just as we can't control perception.

[rant]

DOF is a complex product of photography, presentation, and perception. We can control the photographic factors: camera, lens, aperture, distances, etc. We *might* control the presentation somewhat: enlargement, framing, placement, etc. But unless we're mind-control wizards, we can't control perception: the viewers' visual acuity, state of mind, hallucinations, etc. So we do the best (or worst!) that we can, and to hell with the circle-of-confusion calculations!

[/rant]

If we enlarge to LARGE (non-)standard sizes, DOF differences between formats becomes noticeable. At small sizes, not. I've mentioned making 6x9cm prints of 1mpx P&S images (810x1216 pixels) and contact prints from 6x9cm negatives, printing them on the same paper, glassing and framing them the same, presenting them side-by-side -- and except with a magnifier, they are indistinguishable.

The moral: Keep the image small and you can get away with almost anything!
01-12-2012, 05:43 PM   #100
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Obviously if you cut out an APS-C sized frame from a FF enlargement there's really no difference in DOF. But if you then enlarge that crop up to the size of the FF enlargement you are also magnifying the DOF, COC and perspective from the center of the lens. So the fact that we have a standard set of viewing sizes (well kinda) really makes the difference. Of course we wouldn't be having this discussion if we had a dedicated set of DA lenses that were designed to mimic FF. Which is, I suppose, what Pentax are trying to do.
01-12-2012, 05:43 PM   #101
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QuoteOriginally posted by bossa Quote
Does this mean that my FA*300 F/4.5 is really an 450 F/6 (?) on APS-C?
NO NO NO NO NO!

And NO! Moving a lens does not change its focal length. The lens does not stretch nor shrink magically. The camera frame (film or sensor) crops more or less of the projected image, is all. A 300mm lens on APS-C has the same FOV/AOV (field/angle of view) as a 450mm on 135/FF because it crops the edges of the image.

Old story: Back in the day, I used a 135/HF (half-frame, ~same size as APS-C) Olympus Pen-FT SLR. I put a 400mm T-mount tele on it. I thought OH BOY IT'S LIKE A 600MM LENS! But I was quickly disillusioned by reality -- it was just a 400mm lens with the image sides chopped off.

Crop-sensor cameras chop images; they don't stretch lenses. Sorry.
01-12-2012, 05:47 PM   #102
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On a camera the exit pupil has something to do with the F ratio. On a telescope it's focal length divided by aperture. I assume then that the 'new' f stop size is only related to DOF and not speed of the lens?
01-12-2012, 05:50 PM   #103
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QuoteOriginally posted by RioRico Quote
NO NO NO NO NO!

And NO! Moving a lens does not change its focal length. The lens does not stretch nor shrink magically. The camera frame (film or sensor) crops more or less of the projected image, is all. A 300mm lens on APS-C has the same FOV/AOV (field/angle of view) as a 450mm on 135/FF because it crops the edges of the image.

Old story: Back in the day, I used a 135/HF (half-frame, ~same size as APS-C) Olympus Pen-FT SLR. I put a 400mm T-mount tele on it. I thought OH BOY IT'S LIKE A 600MM LENS! But I was quickly disillusioned by reality -- it was just a 400mm lens with the image sides chopped off.

Crop-sensor cameras chop images; they don't stretch lenses. Sorry.
I know that.. I was just asking about the speed of the lens... The amount of light captured by the sensor depends on the exit pupil as well as the size of pixels etc. I was more or less asking for a clarification of what people are saying re' F stop equivalence.
01-12-2012, 05:57 PM   #104
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They are talking about the DOF equivalent if you were to blow it up. The light passing through is the same; all of it may not be utilized if using a full frame glass on a crop sensor.
01-12-2012, 05:59 PM   #105
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QuoteOriginally posted by JinDesu Quote
They are talking about the DOF equivalent if you were to blow it up. The light passing through is the same; all of it may not be utilized if using a full frame glass on a crop sensor.
Thanks, I thought so.
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