albert lui

<p>Perhaps a discussion on the processing of underexposed/overexposed RAW (with samples representing 'good' and 'poor' exposure) and jpeg images in PS (how to recover from these exposure mistakes, in post process) would make an interesting article.<br />Congratulations on receiving the Hero recognition, Patrick!</p>

<p>As pointed out by Greg Tan's high contrast lighting example, proper exposure of the subject (the person) will result in blowing out the highlights - the DSLR can capture only about 9 stops. Thanks, Greg. Highlight recovery will try to salvage the image for a more natural appearance - I send my apologies to Keith Reeder.<br>

As interesting as it sounds, I am not completely sold on the 'positive compensation' RAW processing w/blending technique that was suggested earlier. Raising the quarter tone and midtone brightness levels will also increase noise. Usually, I just let the (non important) highlights blow out if camera DR is exceeded.</p>

<p>Keith,<br />Having the option to recovery highlights is certainly a nice feature, but I prefer to get the right exposure when the image is captured. Highlight recovery is not perfect - please see any DSLR review at the Dpreview website for details. Thanks.</p>

<p>It is my understanding that highlight recovery is best performed by the raw converter. In this case, DPP would not be the first choice as it doesn't have a highlight recovery feature. For properly exposed images, DPP does a great job. I've read that DPP clips the white point at a certain level, which would probably be a problem for highlight recovery (of over exposed images). I've read that Lightroom/ACR and Dxo raw converters have the highlight recovery feature but I haven't used these software programs.</p>

<p>I agree with Puppy Face's suggestion. I use the EF-S 17-85 a lot, its my most used lens. A great choice for travel and vacation photography. Merry Christmas!</p>

<p>J-P: With adjustment of white point / black point and color saturation in DPP, you can probably get a similar image appearance (compared to ACR or Lightroom).<br /><br />If the image capture is properly exposed, DPP does a more than adequate job for raw conversion (I agree with Colin on its plusses and minuses). I only use PS, with its sophisticated tools, for multipass sharpening. Then I am finished and now have a neutral use master file.</p>

<p>It is reliable and fun to use, on the Elan IIe and I wear glasses. Still, I think ECF is a solution in search of a problem. It doesn't have anywhere near the degree of control and area of coverage, say compared to the Powershot G5, for controlling the focusing sensor point location. </p>

<p>Thanks for the suggestions, Bill. The 50-150/2.8 DC is unique and interesting, but ultimately may have limited appeal because of the increasing popularity of FF cameras. If I was using Pentax, I would probably own the 55-300/4-5.8 (but I am happily 'stuck' with Canon). It looks like a great travel zoom, for a two lens system. Have a happy holiday! </p>

<p>I agree with you on the 82mm filters. Also, the size and weight of the 100-300/4 would be too much to handle for an all day event like an air show, for me. I would love to see a cheap construction high IQ 70-300 small form factor IS lens for APS-C cameras.</p>

<p>Bill,<br>

In the Photozone tests, unless lens A and lens B were tested with the same body, the resolution numbers are not meaningful for comparison. Photozone even advises not to use the data for cross brand comparison of lenses. The differences between camera bodies in: MP count, AA filter strength, NR, etc make cross comparison unadvisable.</p>

<p>Hi Peter,<br />Sharpening/Contrast/Saturation/Picture Style/White Balance settings are automatically transferred to DPP (when shooting RAW), but you have an opportunity to change them - I usually do. In my workflow, Picture Style is Standard, Sharpening is set to zero, Contrast and Saturation remain at default (for 'Standard' Picture Style), and I pick the Shot Setting (white balance) that looks most pleasing. After a brightness adjustment (to taste), the converted raw file is then edited as a tif in Photoshop, where I perform multipass sharpening per Bruce Fraser's 'Real World Sharpening' book.</p>

<p>Yes, the 100-300L has decent sharpness at 300mm. So does the 70-300 IS. But the IS lens is an all-rounder because of IS, while the 100-300L is more limited for travel photography (unless a tripod is used). I use my 100-300L primarily at air shows, where IS usually isn't needed because of panning. The 70-300 IS is a current lens, which is important if repair becomes necessary. I like my 100-300L, but it is important to look at the big picture. </p>

<p>I think this thread has provided a fair assessment of the lens, with a nice example photo from Charles.<br>

Like JDM, I would also be interested in an upgrade to the EF-S 17-85. With the current trend towards FF at the high end, it is possible that the APS-C DSLRs (regardless of make) will be limited to the 'below prosumer' level in the future. If that is the case, will we see an upgrade to the EF-S 17-85 or EF-S 17-55? The crop sensor camera does the job for me, as I rarely make large prints (20x30). I also prefer the generous AF sensor distribution in a crop camera. It is great for sports.</p>

 

<p>Somewhat uneven performance at wide angle is present, but the EF-S 17-85 remains a great choice for travel and vacation photography. I have no hesitation to take pictures zoomed out to 85mm with aperture wide open - I won a contest last year using the lens at that setting.</p>

<p> </p>

<p>Rishi,<br>

Although the 'how and why' of your banding question is interesting, this is 'state of the art' in 2008.  I am sure that the NR software that is normally applied in multipass sharpening (reference Bruce Fraser's Real World Sharpening text) of high ISO digital capture images will greatly reduce the visibility of these artifacts. <br>

I would suspect that Velvia pushed to 25600, even if it is possible, would not be attractive at all.</p>

 

<p>It is the lens+body (the system) that gives the 'final' output (the raw file or jpg).  Looking at it this way, a DSLR with a wide range zoom will easily beat a point and shoot megazoom.  A DSLR has a two stop advantage for SNR and Dynamic Range, according to data at dxomark.com.  It is not even close.   </p>

Even with help from IS, the Pech Merle shot took very steady hands. Excellent vacation and photos, Charles.

Geoff: The somewhat soft corners at 17mm are not fixable by software like DPP or PTLens. That is why I consider 17mm to be the weak point. Whether or not it impacts the picture seems to depend on the subject. In the Victoria Peak view, I hardly notice it. In that shot, CA and distortion were effectively corrected by DPP.

 

Charles, Jeff: I enjoyed reading your insightful, balanced discussions on the 17-85. Very nice images too.

 

I think that the versatility of having this focal range and IS together, cannot be overstated. I like the performance at 85mm too - here's a night shot (camera was hand held at 0.1 sec).<div></div>

Charles Griffin, the voice of reason!

 

Here's an image taken at 17mm, the weakest focal length of the 17-85. Optical performance is good enough for me.<div></div>

The 17-85 is a great lens for travel photography. The IS (along with high ISO) provides low light and night shooting possiblilities. The lens has very good sharpness even at 85mm. At wide angle (around 17 mm), the extreme corners start getting soft, something lens correction software cannot fix (unlike vignetting/distortion/CA). It is the lens I take on international travel (when I want to travel light). I would buy it again.

I agree with Ian R. The DPP lens correction works nicely with the EF-S 17-85, especially at wide angle (where it is needed the most). My nominal settings are: Peripheral Illumination (94-96) - A slight darkening of the image corners looks natural, in my opinion; Distortion - Sometimes backed off from 100. Distortion is affected by subject and distance, so the amount of correction (if any) is a subjective call (if one is picky); Chromatic Abberation - This parameter is focal length/subject/lighting dependent. I usually leave it at default strength, if I choose to apply the correction. Usually it is not needed at the telephoto end. My camera is the XTi, which doesn't send subject distance to DPP. I wonder if a distance info supported camera like the 40D would enable better optimized lens correction in DPP (less user tinkering needed)

I'd take any camera mounted to the luxury 24-70L lens. If I had to hike with this rig, I'd definitely use a photo backpack for balanced weight distribution.

In addition to the benefits already mentioned by the earlier posters, telephoto photography is more enjoyable with an IS lens. Having a stabilized view is nice - no more headache inducing blur.

Most of the time, I use the default CF settings on the XTi except for CF1=4 (cross keys for AF point select) and CF2=2 (enable long exposure NR). I think that CF4=1 is great for accurate exposure but does not work as well for sports or when a non-photographer uses the camera. Not being a fan of manual metering, I use Evaluative metering. Shooting with 'expose to the right' (ETTR) as my goal for the histogram, I apply exposure compensation (EC) as needed. In my opinion, Av/Tv/P metering stimulates creativity by allowing me to concentrate on composition. The way EC is performed on Rebel series cameras is not as convenient as xxD cameras, but I've become used to it.

 

My RAW workflow goes like this: Canon DPP for raw to tiff conversion with image brightness adjusted if neccessary (often it is, with ETTR). Photosharp for sharpening per the Bruce Fraser book 'Real World Sharpening' or something like that. He was one of the contributors to Photokit sharpener software, so I would think it is a very good program, but I have not used it.

 

My favorite photography is travel photography, so I am all for a light kit and I usually prefer EF-S lenses, where the choice exists. The exception would be telezooms: Telezooms designed for crop sensors aren't that much smaller than FF telezooms, so I would prefer the EF 70-300 IS over, say the EF-S 55-250 IS.

The 'Coffee Grinder' (100-300L) is a great fit with the 1.6x DSLRs (xxD, xD). The main weakness, noticeable

vignetting at 300 mm @ f5.6 in scenes with lots of sky, largely dissappears because of the cropped sensor. The

lack of a built-in tripod ring reduces the lens' appeal to serious landscape shooters. Not having IS will require the

travel photographer to crank up the camera's ISO. Autofocus, a system performance (body+lens), is not as robust

compared to the newer lenses, but I have managed to get some keepers. The 'Coffee Grinder' is probably not the

first choice for any single photography category, but in my opinion it is best suited for crop camera sports pictures.

It is the bargain price high image quality lens solution.<div></div>