More on Bokeh

Mike Johnston, in his short publication "Lens Bokeh Ratings," states the following generalizations about bokeh (out-of-focus blur):

I’ve found as a general rule that bokeh gets progressively more problematic:
• the larger the aperture
• the closer the focus
• the more distant the background
• the more contrasty the background

I think that when we discuss which lenses produce nice OOF blur (bokeh) compared to those that don't, we too often compare lenses under the worst of circumstances. For example, here are two shots of my sons with the 50/1.4 under nearly the worst of circumstances (Click on image for full size):





From these, one might conclude that the 50/1.4 harshly renders OOF blur (bokeh). This is far from true. Compare the OOF blur from the 50/1.4 at f/2.8-f/4 with any 50mm lens irrespective of price range, and it will compete well. Conversely, take the last generation pre-aspherical 35mm Summicron-M and shoot it wide open with a close subject and a distant, contrasty background. Even the so-called "King of Bokeh" will render a harsh OOF background blur under such circumstances.

Now see how the 50/1.4 renders an extremely challenging background at f/2.8:



Significant improvement. Now take a few moments to consider William Castleman's bokeh comparison of the 50/1.2L and 50/1.4.

An interesting consequence of this effect of stopping down on the quality of bokeh - independent of the quantity of background blur - can be seen in this bokeh comparison between the 35L on the 30D and 50/1.4 on the 5D.

Read More......

Posted by Amin

Comments

Panasonic Announces the Super-Tele Compact for Me.


Not long ago, I posted the following:

"... my family recently moved from Baltimore City out to the Maryland suburbs, very close to this great park which is home (or hunting grounds) for a variety of wildlife including herons, beavers, swans, geese, and eagles. For the first time, I am tempted to get some equipment with true reach. Still not sure whether I should stay compact (eg. Panasonic FZ50) or think about carting around a long lens for the DSLR. If I weren't lugging around two small children with me, it would be a much easier decision!"

Shortly after that, I posted, based on what turned out to be an incorrect source, that Panasonic would be announcing new cameras on July 17th. I was hopeful that the new Panasonic cameras would include an FZ50 replacement, but I think that what they instead introduced is an even better solution for me.

Today, Panasonic revealed the DMC-FZ18. Amongst its many features, the ones which interest me the most are the following, some of which are unchanged from the FZ8:

- 18x f/2.8-4.2 zoom with focal length range equivalent to 28-504mm on a 35mm camera
- 8.1 MP 1/2.5" CCD sensor
- Image stabilization
- RAW + JPEG
- SD/SDHC storage
- Spot metering mode
- +/- 2 settings on NR, sat, contrast, sharpness (more control than FZ8)
- AE/AF lock
- Good EVF

The only other camera to include almost all of this is the Olympus SP-550, which has not gotten great reviews. It is clear that packing in this many features must come at the cost of certain compromises. However, Panasonic has consistently offered class-leading (IMHO) compact super-tele models, so I am confident that they made good compromises with this one.

Certainly this camera is in a different class than the FZ50, which is probably the finest currently-produced "bridge camera" available. I continue to look forward to what Panasonic has in store for the upgrade to that model. The FZ50 is more "DSLR-like" in both size and features, offering important advantages such as a larger sensor and mechanical zoom. If they keep the 1/1.8" sensor in the FZ50 replacement (assuming there is one) and extend the zoom range to 28-504mm equivalent, I'd have to imagine that there will be a size increase - or worse, a slower lens.

There are predictable downsides to this camera. Panasonic stuffed 8MP into a 1/2.5" sensor (24.7mm^2). By comparison, the FZ50 puts 10.1MP in a 1/1.8" sensor (38.2mm^2), a Canon 30D puts 8.2MP in a 337.5mm^2 sensor, and a Canon 5D puts 12.8MP in an 864mm^2 sensor. In terms of thousands of pixels per square mm then, they come out at roughly 324 (FZ18), 264 (FZ50), 24.3 (30D), and 14.8 (5D). With that little light hitting each pixel on the FZ18, it will inevitably be challenged in terms of dynamic range and noise, especially in low light conditions (see here). Making things worse, Panasonic has a heavy-handed, detail smearing approach to noise reduction (NR) using their Venus III in-camera processing engine, have been known to apply NR to RAW files (see here), and a very popular RAW processing engine has made heavy (IMO) NR mandatory for those who use it (see here).

I can't imagine that such a small sensor camera will be any good for birds in flight, but I do think it will satisfy my very limited wildlife requirements. The FZ18 will be available in September at a retail price of $399.95, and I will be buying one of the first ones I can get my hands on. Early adopters do get burned sometimes. However, Panasonic has been consistently good in this class of cameras, and the main predictable downsides are compromises which I am prepared to accept.

Read More......

Posted by Amin 2 comments

Do Canon Lenses Have a Look?

Interesting brief article here on modern lens history from the perspective of a Minolta user.

Was sad to read "Canon lenses don't have a 'look'," but I'd probably agree with that. While individual Canons may have a look, I really can't think of a look that applies to the entire brand as a whole. I guess that could be considered a good thing or not. Thoughts?

Read More......

Posted by Amin

Comments

CV 28/35 Minifinder

All images used with permission, courtesy of CameraQuest.

The Cosina Voigtlander 28/35 Mini-Finder was introduced at PMA in 2004, came in chrome or black, and contains brightlines for 28 and 35mm which are visible at all times. From what I can tell, this model has been discontinued, and only the larger viewfinders are being made. However, one can still purchase this viewfinder here from CameraQuest. I bought mine a few days ago and received it yesterday. For my purposes, this viewfinder makes an excellent companion for the Ricoh GX100. It's far more compact than the Ricoh EVF and avoids the lag associated with the image reaching an EVF. It is very bright for its size, and the image seen is sharp. Eye relief is just acceptable. Wearing eyeglasses, I can make out the entire 28mm brightlines just barely. Framing via the Voigt Mini-Finder is in 3x2 aspect ratio, so in practice the vertical FOV is greater than that included within the brightlines, whereas the horizontal FOV is accurate. It hasn't taken me long to adjust for this issue. The major limitation, of course, is that the VF has guides only for 28 and 35mm, not 24, 50, or 72mm (the other focal length equivalents supported by the GX100 step zoom). However, 90% of my photos are at 28 or 35mm, so this works well for me. For the other focal lengths, I will either compose with the LCD or simply estimate using the OVF. One final consideration is that this finder blocks the GX100 popup flash. I hardly ever use this flash, so it won't bother me. However, since the the viewfinder has to be physically removed to use the on-board flash, it is certainly something to consider.

I did consider buying the Ricoh GV-1 OVF, which is made for the GRD. However, as the GV-1 is offset to match the location of the GRD lens, it won't match the midline position of the GX100 hot shoe relative to the lens. Furthermore, the GV-1 is rather large and lacks a brightline for 35mm.

Here are a couple more views of the CV 28/35 Mini-Finder, again used with permission from Stephen Gandy from CameraQuest.


If I get a chance, I'll update this post later with some images of the CV 28/35 Mini-Finder mounted on the GX100.

Read More......

Posted by Amin

Comments

Canon Compact Cameras to see Better Sensors Soon?

I've expressed my disappointment in the lack of compact digital cameras offering excellent image quality on several occasions. As I pointed out here, much of it has to do with sensor size. In particular, as a long-time Canon user I have been disappointed in the lack of innovation from Canon in the compact segment.

Canon has announced that it is building a new $451 million factory to build CMOS chips. From the Reuter's article: "The CMOS chips will be used in both single lens reflex (SLR) models as well as in some compact models. Canon's compact cameras have to date used a different type of image sensor called a charge-coupled device (CCD)." A CMOS versus CCD technical discussion is beyond the scope of this brief. What is interesting is that Canon plans to take control of its own sensor production for some compact models as well as to use the same sensor technology in some compact models as they do in DSLRs.

It remains to be seen whether Canon is bringing some of it compact camera sensor production in-house just to cut costs or also so that they can improve image quality. Hopefully they can do both.

Read More......

Posted by Amin

Comments

New Panasonic Cameras Coming July 17

As some of you know, Panasonic has sent out invitations for a July 17 event in New York City at which they will be announcing new cameras. Some are speculating that we will see a lower priced DSLR offering. I'm hoping that we see some sort of upgrade on the FZ50. At any rate, I'm excited to see what they bring out. Panasonic has certainly been more innovative lately than Canon or Nikon in the compact digital camera space.

Read More......

Posted by Amin

Comments

Bring on 1" Sensors (Bridge Cameras, Part 2)

Recently, Thom Hogan updated an article describing the sort of compact camera he wants. Many have also read of Mike Johnston's desire for a DMD. Thom believes that the technology is currently available to design a compact camera with a relatively fast (f/2.8-4) zoom and an APS-C sensor. I remain skeptical about this; however, thinking about these issues in camera design has me wondering again about my old friend, the bridge camera.

Before continuing, it would be helpful to review relative sensor sizes among currently available cameras. The following image demonstrates some common relative sensor sizes. Of course the actual sensors are smaller than depicted.




The entire image corresponds to the relative size of a "full frame" digital sensor such as the one in the Canon 5D. The red, blue, green, yellow, and purple lines correspond to the relative sizes of APS-C, 4/3", 1", 2/3", and 1/1.8" sensors respectively. The background image is there to illustrate the "crop factor," which is beyond the scope of my brief post here. The largest sensors in current, very compact cameras are around 1/1.7". Not too long ago, we had 2/3" sensors. Now, the next step up in sensor size from 1/1.7" (which would be between purple and yellow in the image above) is a huge leap to 4/3" (depicted above in blue). Comparing the smallest 4/3 system, the Olympus E-410 with kit lens, with DSLR systems based around the next step up in sensor size (APS-C) demonstrates the fact that smaller systems can be designed around smaller sensors. The, as of yet vaporware, Sigma DP1 promises a compact camera featuring an APS-C sensor. Likely this is possible in part since no mirror mechanism is incorporated, and in part because the DP1 features a prime lens of modest speed (f/4).

Why is there a leap from 1/1.7" to 4/3"? Surely a non-SLR digital camera with a 1" current-generation-technology sensor could be designed to be smaller than any DSLR + equivalent focal length range lens kit. Such a non-SLR camera would certainly provide better image quality and greater potential for shallow DOF than any current, smaller sensor compact digital cameras. The way I see it, these 1" sensor cameras could be made no larger than current "superzoom" cameras such as the Canon S5 IS or Olympus SP-550 by incorporating the tradeoff of a larger sensor and a more modest (2-3x) zoom range. Take, for example, my old Leica Digilux 2 (D2). The D2 could be made more compact today by 1) applying current generation design methods, and 2) making the lens non-fixed in length. The second of those two changes is not something I'd want, but it's worth mentioning that it could be done. In addition, one could presumably increase the D2 sensor size from 2/3" to 1" without increasing the overall size (largely determined by the lens size), if one were willing to accept a slower zoom, such as f/2.8-3.5 rather than f/2-2.4.

It makes no sense to me that we have only cameras with sensor sizes of 1/2.5", 1/1.8", 1/1.7", 4/3", 1.8" (APS-C), and 35mm. There is a large gap between 1/1.7" and 4/3" that is waiting to be plugged with 1" sensors. I am confident that bridge cameras derived from such sensors could be profitable in 2007 and beyond.

Read More......

Posted by Amin 2 comments

PopPhoto Reviews the Ricoh GX100

Continuing on with GX100 coverage, I was glad to see another professional review today, this one from Popular Photography. Their summary statement was as follows:

"The GX100 is a highly competent camera that's easy and fun for both the casual shooter and the serious enthusiast to use. We like it. But we'd like it more if it cost a little less and had less noise at high ISOs."
Compared to the G7, they had the following to say:
"The Ricoh scores higher on image quality -- in both noise and resolution -- and offers RAW capture, absent on the Canon."
Overall, I found it to be a clearly positive review and worth a read.

Read More......

Posted by Amin

Comments

More GX100 Appreciation

I'm beginning to settle in with the Ricoh GX100 in a way that I never realized with the Canon G7. The following is just a simple photo which highlights a few aspects that make the Ricoh special amongst current compact digital camera offerings.

(Click for full size)


The first and perhaps the most significant feature is that the zoom range starts at 24mm (35mm film equivalent), which is the focal length I used here. Second, it gives one access to the RAW file, which I needed in order to bring push the exposure enough to selectively bring out some shadow detail to match the scene as I recalled it. The image stabilization performs well, allowing me to get a blur-free ISO 80 image in this relatively low light. Finally, it is very compact, facilitating the important matter of having the camera present.

As an aside, my family recently moved from Baltimore City out to the Maryland suburbs, very close to this great park which is home (or hunting grounds) for a variety of wildlife including herons, beavers, swans, geese, and eagles. For the first time, I am tempted to get some equipment with true reach. Still not sure whether I should stay compact (eg. Panasonic FZ50) or think about carting around a long lens for the DSLR. If I weren't lugging around two small children with me, it would be a much easier decision!

Read More......

Posted by Amin 5 comments

My Main Digital Camera is Four Years Old.

My dad recently asked me why I generally carry a four-year-old camera, the Leica Digilux 2 (D2), when I have several more recent bodies to choose from. Clearly I am not alone. The Leica D2 and its Panasonic clone, the LC1, continue to find themselves in the hands of photographers who own much newer and more expensive equipment. Despite known sensor susceptibility to failure, these cameras also command a very high cost on the used market considering their age. They are 5 megapixel cameras, only go up to ISO 400, take about 5 seconds to buffer a RAW image, and don't autofocus very quickly. Why then do we carry them? Some love the appearance, feel, controls, and optically-great DC Vario Summicron lens. I carry it for the following reasons:

- 28-90mm (equivalent) is a nearly perfect focal length range for my general needs.
- With its relatively large (2/3") sensor, the D2/LC1 can achieve some nice portrait background blur at 90mm and f/2.4.
- The f/2-2.4 zoom is nice and fast.
- The relatively large pixel pitch makes for good dynamic range and tone separation.
- The noise at higher ISO values has a more pleasing quality than that of any other small-sensor digital camera I have tried.
- There's something about a mechanically-linked zoom that just feels right.

No small-sensor digital camera currently made can replace this one in my kit. Until now, no cameras with larger sensors and an equivalent zoom range have been compact enough to replace it. None are as quiet, which is another thing I appreciate about the D2. I do have my eye on the new Olympus E-410 with kit lens, which looks to be a viable alternative in most respects. If you are interested in learning more about the Digilux 2, I recommend the following two reviews:

http://photo.net/equipment/leica/digilux2/
http://www.luminous-landscape.com/reviews/cameras/leica-digilux2-part1.shtml

Read More......

Posted by Amin 2 comments

 
Copyright 2007 | Andreas08v2 by GeckoandFly and TemplatesForYou | Design by Andreas Viklund
TFY Burajiru