bill owens

<p>I just finished the film...a phenomenal documentary. Although the issue was briefly discussed in the film, I assumed it would be trivial to judge if a lens was at work by looking for barrel distortion, especially given the simple lens involved. I Googled for a while to understand what level of distortion might be introduced if a large camera obscura set-up includes a simple lens (rather than just a pinhole, which I know creates no distortion)...but came up empty. In any case, looking at the original and Jenison's art using Photoshop's lens correction tool, I see little meaningful evidence in the edge areas of distortion.<br>

Another clue that wasn't mentioned is brush strokes. Anyone painting over the edge of a mirror would probably paint primarily in small strokes parallel to the mirror's edge...has anyone explored this?<br>

Anyway, a great film.</p>

<p>Thanks for the responses. I experimented with scale to fit to force pixelation, and better understand the benefit of resampling beforehand.</p>

<p>In CS5, is is best to Resample an image (where you can select the method of resampling, e.g. Bicubic Smoother, and the PPI) then print as is (i.e. no Scale to Fit Media), or just leave the image as is and use Scale to Fit Media in the print dialog? What does Scale to Fit assume? Will it matter?<br>

Thanks</p>

<p>Thanks all. WMP is working fine for combined video/photo playlists. Will also try Irfanview and some others. But first I'm trying to find a blu-ray player or receiver that will successfully play my large photo and AVCHD video file collection (from a Canon camcorder) off my PC via ethernet. My receiver does a great job with my PC music library (WMA lossless). So far, the new Panasonic BD75 blu-ray I have is not being recognized by my PC, although the player sees my PC on my network but I cannot get it to see content in the PC folders....</p>

<p>Chris,<br>

I was obviously not doing this right on WMP. I was sort of looking for a way to dump new photos or videos of interest into a common set of folders on a network drive and have them all display via WMP or whatever without having to recreate a playlist each time I added new ones. Will keep exploring how to use playlists/libraries in WMP, but you've solved my immediate problem. Thanks.<br>

Now if I could only get music to play simultaneously with the photos but not the videos, and get transition effects, and get world peace, and....</p>

<p>Can anyone point me to software that will essentially do a slideshow of BOTH photos and videos (whether in order of date, file name, random or whatever)? Windows Media Player or Windows Media Center will do either, but not together as far as I can tell. I just want to be able to run a slideshow of my family photos and videos without having to do only photos then switch to videos then back etc.... Not particularly eager to have to create/render a slideshow then have to recreate it every time I add a new video or photo.<br>

Thanks</p>

<p>

<p>I do mostly family shots and a ton of "volunteer" shooting, such as my daughter's gymnastics team last week, so this may have no relevance for you. Anyway, I basically shoot only in RAW then save on a primary hard drive in a folder structure that begins with year then has subfolders by subject. I batch rename the files in Bridge to include subject-date-number, e.g. Aruba_2010_05_22_0003.raw (so the file will stand alone when moved out of the folders, so the files will sort properly, and so the date is seen when doing slideshows where the filename can be seen). I will eventually do some tagging, but the file naming alone works 98% of the time for finding files. I have been rigorous about this structure/naming since my first digital shots in 1993 and it has worked great. All files are backed up to a second drive before the camera card is cleared. (I will eventually set up RAID storage.) A third backup is done periodically.</p>

<p>I open the files through Bridge directly into ACR, then open in PS, edit and save usually as jpeg in a subfolder titled E if edited only and ES if edited and sharpened (depends on anticipated printing/display requirements). TIFFs are too large and slow to handle for my tastes. If I want to retain the resolution and editing, I save the psd's, but I do this rarely. Just re-editing most files is not that big of a deal for my needs, and the ACR settings are captured in the xmp files.</p>

</p>

<p>I'll eventually do a massive batch conversion of all my RAW files to DNG for long-term archiving, since who knows what will open these proprietary RAW files 20 years from now.</p>

<p>Found one local today! Thanks for the feedback.</p>

<p>I've been watching the reputable sites (B&H, Adorama, etc.) for some time waiting for the 550 (body only) to show something other than Out of Stock or Unavailable. Some other vendors show availability gouging at $100+ over list, and I could probably get the kit now for $849 (then sell the lens). I read the 7D was very slowly stocked as well.<br>

Anyone have a clue as to when/where a body-only will be available for $799 from a reputable dealer?</p>

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"http://d6d2h4gfvy8t8.cloudfront.net/6249882-md.jpg"></center>

<p>I say go wild....</p><div></div>

<p>The Canon paper is quite good. It does mention the one clear advantage of the smaller sensors--smaller bodies and lenses.<br /> <br /> The viewfinder advantage will always rest with FF.<br /> <br /> The DOF advantage of the FF is under the circumstances of using the same lens/aperture where you have to back up with APS-C for the same image and thus lose DOF, but with a wider lens on the APS-C doesn't the DOF argument go away?<br /> <br /> It seems that the larger FF sensor will always have an advantage in terms of more total pixels, or larger individual pixels, but the 7D suggests we are reaching a point, speaking practically, where the extra light-gathering advantage of the larger FF pixel is becoming irrelevant in terms of dynamic range and high ISO noise.<br /> <br /> In the trivial category, the smaller sensor suffers more lost data for a given dust particle, but the shutter has less distance to travel over a smaller sensor for higher FPS.<br /> <br /> In my mind, it's coming down to a bright viewfinder versus less weight. The weight advantage is not trivial. Look at reasonably matched equipment sets in terms of focal lengths and apertures (assuming all other factors will eventually be reasonably equal): a 5D2 + 24-70 + 70-200f4 + 400f4 versus a T1i + 17-55f2.8 + 28-135 + 300f4. You could carry TWO APS-C sets and still be lighter than the FF suite! For me as a casual photographer who likes to lug his gear all over, I'll take the smaller/lighter option.</p>

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<p>Tim, thanks for bringing that article to photo.net's attention. Roger Cicala has written one of the best industry assessments I've ever read, and done so in a surprisingly logical and clear style.</p>

<p>Jason, I'll be interested to hear some responses on the 2nd curtain flash with the XTi--I couldn't get it to work with my 580 either.</p>

<center><img src="http://gallery.photo.net/photo/6991003-

md.jpg"></center>

<p>Unfortunately the caching didn't work. I tried setting up a new folder with just a few images--all the thumbnails showed but none of the previews.</p>

<p>Also, I know I can convert the images to DNG...just trying to avoid that at the moment....</p>

<p>I just replaced my Camera Raw.8bi files with ACR 4.6 in 2 locations:<br>

Adobe Photosshop CS3 > Plug-Ins > File Formats<br>

and<br>

Adobe Bridge CS3 > Plug-Ins<br>

so I could process some Nikon D90 images. The first 25 thumbnails (of 425) show up fine. However, the rest of the thumbnals will not resolve in the Content pane. Also, the images that show in the Adobe Bridge Preview pane are small (thumbnail size). All images open fine in Photoshop. <br>

My Canon raw files work fine. I've tried different preferences settings to no avail. Any suggestions?</p>

<p>Thanks for the answers.  Arash, my previous post was to help me better understand how Canon AF works, and the reponses were very helpful.  This post was to get specifically at what Canon repair could/would do for me.</p>

<p>I'm on my 4th digital Canon SLR and am experiencing some significant lens-specific focus issues for the first time.  Check <a href="http://billowens.smugmug.com/gallery/6776630_jpTy4#433148143_NX2js">http://billowens.smugmug.com/gallery/6776630_jpTy4#433148143_NX2js</a> to guess which one(s).  I'm not posting to get into a debate over whether I'm using autofocus properly nor whether I have tested correctly.  I am actually looking for a specific answer to:</p>

<p>Is it true that Canon can adjust an XSi at their repair facilities for specific lenses, including 3rd party lenses (I will, of course, send the lenses), and not just make a single overall adjustment?</p>

<p>If not, maybe it's time for that 50D with microadjustment....</p>

<p>Thanks all.  I feel much more knowledgeable about AF now.  Now on to the practical matter of adjustments to my camera...which I will make as a new post.</p>

I was reading the instructions for the Nikon D70 Focus test chart by Tim Jackson and it indicated the D70 uses

contrast AF, so I incorrectly assumed the same for my XSi.

 

Anyway, I guess I'm still a bit confused. I just read the very informative article (thanks Arash) on phase

comparison AF and that indicates that the camera will estimate how far out of focus a lens is, then tell the lens

how much to correct in a single predictive action. I could see how different lenses would lead to different

residual focus errors.

 

However, it seems to me that whether a contrast or phase comparison AF is in use, if you focus again on the same

target, the focus error should shrink each time you refocus. In other words, when you refocus, the AF should see

that there is still a contrast/phase discrepancy, and tell the lens to adjust again but this time by a smaller

increment, right? But it doesn't. I guess once it's decided that a focus adjustment is "good enough" for a

given lens, it quits. Oh well....

Can someone explain in basic terms why autofocus accuracy varies lens to lens for the same camera? If the

camera processor is trying to optimize contrast on a single-axis or cross sensor, won't it just tell whatever lens is on

the camera to focus in or out until maximum contrast is achieved? Why would one lens focus perfectly and another

over- or undershoot the focus command from the sensor? And why doesn't the processor then re-correct the bad

focus (re-optimizing the contrast)?

I'm just seeing all these responses at once for the first time. The overwhelming humor promptly teared my eyes and blurred my vision, serving, in fact, as a natural despeckle filter, removing the mysterious object from the image, and putting my curiosity completely to rest. Well done!

 

 

 

I lean toward poop.