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10-11-2010, 05:02 AM   #31
raz
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f/18 is too extreme I think, it will give you diffraction. If you want to have a lot sharper results, use a normal F number.

Look here , very big differences in the f/22 compared to f/8 images. Taken on a medium format camera with 39 Megapixels.

Understanding Lens Diffraction


Last edited by raz; 10-11-2010 at 05:11 AM.
10-11-2010, 08:03 AM   #32
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QuoteOriginally posted by raz Quote
f/18 is too extreme I think, it will give you diffraction. If you want to have a lot sharper results, use a normal F number.

Look here , very big differences in the f/22 compared to f/8 images. Taken on a medium format camera with 39 Megapixels.

Understanding Lens Diffraction
Medium format and landscape often means you have little choice but to select stopped down apertures if you want the picture. Some diffraction is sharper than out of focus and better than no picture at all if you're after the perspective a near normal lens and not a wide angle.
10-11-2010, 09:36 AM   #33
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Now the highlights have been adjusted using manual blending. So please don't try to judge the DR, since I didn't spotmeter the exposure differences, we don't have the right info to begin with.

Digitalis, I think the flare is due to the very strong light coming from the bottom right of the bridge (and also maybe due to the use of GND with slight water spray or a few scratches on it) , and it disappeared at the very end because of the Cokin Z-pro filter holder that worked as a funny, lame lens hood. Was there anything I could've done about it? Probably not so much.

Claude, I prefer to get started with precisely positioning the GND and use manual blending to save the scattered highlights or shadows. I understand how you would like to use your hand to partially burn the highlights in the large format photography, but since I only had a few mins to get the shot and I didn't know how much I should shake my hand in front of the lens, I would still have gone with bracketing / manual blending, which I consider one of the biggest strength of digital photography. FYI, the GND was placed right in the middle. Even though the camera offers ISO 100, I used ISO 200 since I figured that ISO 100 would not give me any better IQ than 200 (since it's an 'expand'ed option), and usually keeping the exposure under 2 mins is very important in digital photos to suppress the long-exposure noise (due to the heating of the sensor). I find 4 min ISO 100 worse than 2 min ISO 200 on the Canon 5d II.

p.s. Marshall's beach is one of my favorites, despite all those wooden steps. : )

Raz and Tuco,

I will make it clear on this issue. I know what diffraction and DOF are. And I know how to control them. This time I went with stopping down knowing that I will lose some IQ due to diffraction. The main reason was because the exposure was 2.5 mins and it took another 2.5 mins for noise reduction. I had a very tight time window (which is usually 40-45mins after sunset for this kind of shots) so I needed to do it right the first time. I normally shoot at f/10-f/13, which I think is the best compromise between DOF and IQ for this particular pixel density. For this shot, I was shooting at 75mm (FYI, sample 1 was at 45mm, f/13 and horizontal, which is a totally different game than this : that I screwed up the focus due to the AF malfunction and the lack of experience with this particular lens system)

If I'd been dealing with 1-2 sec regular exposure shots, I would've gone with focus bracketing (with wider aperture), which is one advantage of digital photography.


(Con Fuoco, 2010, Mammoth Hot Springs, Yellowstone National Park, Wyoming, USA.)

The above shot was taken at 55mm, f/13 with the Canon 5d II and I bracketed two sets of images with different focus and blended them later to extend the DOF.

Thanks for the comments and discussions, I hope I could get you guys better shots soon.

- Hark

Hark Lee Fine Art Photography
www.harkleephotography.com

Last edited by harklee; 10-11-2010 at 12:16 PM.
10-11-2010, 10:40 AM   #34
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Lovely landscape. Sure, when you fabricate your picture in an image editor, all sorts of new possibilities exist. I was coming from the perspective of the single shot capture.

10-11-2010, 12:08 PM   #35
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Tuco, with all due respect, camera is just a tool to capture an image as close as possible to what the human eye can perceive. If I intentionally photoshopped in a thing or two that did not exist in the frame or took out what I didn't want in my photo, it would be what you would call 'fabrication'. Blending in the shadows or highlights that the camera cannot capture in a single shot, or extending the DOF using focus bracketing is to overcome the limitations of the current technological offerings, not to 'fabricate'.

- Hark

Hark Lee Fine Art Photography
www.harkleephotography.com

Last edited by harklee; 10-11-2010 at 12:18 PM.
10-11-2010, 12:35 PM   #36
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Harklee, about the 100 ISO bulb noise you're experiencing, there might be an experiment worth trying when you've got an idle evening (and apologies if this is teaching grandma to cook eggs). See what happens if you take a few bulb runs a few minutes beforehand, to heat the sensor up as such, so that it's at a constant temperature during the time you actually take the shot that matters. I can't remember where but some fella was singing the praises of this the other day, his discovery being that it was the temp differential rather than the absolute temp causing his noise. Of course this wasn't the 645d so it might be completely different here but it can't do any harm to at least try I'd have thought.

ps. Yellowstone sure looks photogenic, I envy you
10-11-2010, 02:51 PM   #37
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Don't get me wrong, harklee, I'm not saying there is anything wrong with using more than one picture to make one. It's just a different photographic style than the make-what-you-can from one shot style is all.
10-12-2010, 05:18 AM   #38
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QuoteOriginally posted by harklee Quote
Tuco, of course. But the problem is that 645 FA lenses don't have DOF scales on them. Since I was using the wide angle zoom FA 33-55mm, even the focus scale is not that helpful when your target is between 7ft and infinity, because these are the last two marks on the focusing-meter and no other numbers in between.
Focus the lens slightly shorter than the infinity mark and stop it down to F:16. F:13 is the 33-55's best aperture but F:16 makes sure you get the near-far DOF needed for most landscapes unless you have a real close foreground. Many of the images in my gallery is shot with this lens...

10-12-2010, 07:10 AM   #39
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That Canon 5D II image is absolutely breathtaking, I can just eat up that color and tonality....VERY impressed.
10-12-2010, 09:30 AM   #40
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QuoteOriginally posted by pcarfan Quote
That Canon 5D II image is absolutely breathtaking, I can just eat up that color and tonality....VERY impressed.
Me too. It is hard to believe that this was done using focus stacking. It has been my opinion for some time that is a bogus technology. Apparently I was wrong. Perhaps my recent view camera purchase was in vain


Steve
10-13-2010, 07:27 PM   #41
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Steve

Why did you get a view camera?

Claude
10-13-2010, 07:43 PM   #42
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QuoteOriginally posted by claudefiddler Quote
Steve

Why did you get a view camera?

Claude
For the movements and as a relatively low cost quality upgrade from my APS-C dSLR, but mostly for the movements. The type of near-far sharpness on the 5D picture was previously only possible with lens tilt/swing.


Steve
10-13-2010, 08:28 PM   #43
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QuoteOriginally posted by stevebrot Quote
Me too. It is hard to believe that this was done using focus stacking. It has been my opinion for some time that is a bogus technology. Apparently I was wrong.
It is used extensively in macro and I have experimented with same. It is definitely not bogus but a useful technique. In fact I have no idea why some genius doesn't build it into the next APS-C camera as an automated feature. Choose your initial focus distance, your final focus and how many shots to "bracket". Have the camera take the shots. The advantage would be no chance of accidental movement between each frame.
10-14-2010, 04:30 AM   #44
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I think for 44*33 mm sensor f/5.6-f/11 is optimal.
10-14-2010, 04:54 AM   #45
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QuoteOriginally posted by stevebrot Quote
For the movements and as a relatively low cost quality upgrade from my APS-C dSLR, but mostly for the movements. The type of near-far sharpness on the 5D picture was previously only possible with lens tilt/swing.


Steve

I cannot see that this picture should be impossible to shot on 35mm. The ones below, with very close foreground, are all shot on medium format.







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