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My D200 and 18200 mm lens and 1224 mm lens have arrived

Larry, you have been a big help to me in the past and wondered if you could recommend a good source of info for the use of the unsharp mask. I am especially unsure about parameters and how they affect the image. I use Corel Paint Shop Pro X and find some of their info confusing. Do you know of a link or book that goes into digital editing clearly with detail? Thanks. Tom
 
Nope, but perhaps I can help. Unfortunately, PSP does not use Lab Mode like Photoshop, but the following does take up some of the slack. On the unsharp mask dialogue, there is a selection that says "Luminance only" make sure you click it. If you don't, sharpening will make changes in saturation and overall tonality.

There is also a little tab in the lower right hand corner of the window that allows you to pull it to get a much larger view of the two windows to compare - do so.

While I would recommend at starting radius of 0.25 with Photoshop, that radius seems to have little effect in PSP. Instead, set the radius for 0.5 or 0.6 and the strength at 500. I have never found much use for the clipping setting, so leave it at zero.

Now watch the right-hand window and begin reducing the strength to the minimum point where the picture looks sharp. You can tug the strength slider back and forth until it looks right to you. You can be fairly bold with it, since at a sub-pixel level, large changes make quite subtle differences.

To compare the subtlety of sub-pixel sharpening, try one with a radius of two pixels instead. Things get REALLY ugly as the radius grows larger. Grain or noise is also much more emphasized with larger radii. However, if the picture is still soft at 0.6 and 500, the only course of action is to go to 0.7 or higher. Do it 0.1 at time.

Practice with it on a variety of images, and in the end trust your eyes. Hope this will do it for you.

As an aside, the term "unsharp mask" seems an oxymoron. It comes from the film darkroom. Kodak made a film called "Unsharp Masking Film", which when exposed and developed produced a soft fuzzy negative image. This was put in contact with the original image in perfect register and the sandwich was printed on somewhat higher contrast material. It worked just like the digital version.

You can actually try it virtually in PSP. Duplicate the background layer, and select the duplicate. Reverse it to negative, and blur it - say a 3 pixel Gaussian blur. Pull the layer slider to around 40% and you will see a rather muddy version that is positive. Merge the layers and use Histogram Adjustment to bring it back to full dynamic range. You will have a much sharper image, using an ACTUAL unsharp mask, just as dye transfer printers used on a daily basis in their darkrooms. It is a lot more bother, but does a decent job.

larry! http://www.larry-bolch.com/ ICQ 76620504
 
I have had on order the new Nikon 70mm-300 mm lens. Has anyone seen this lens yet or even better has anyone used it yet?
 
70-300 lens

I have that lens, and so far, it's very nice. I haven't spent the time with it, that I want to, but I do like the lens.

I'll check and see if I have any shots I can post later.

I'm just a beginner at this, so don't expect much … the doctor told me to have fun, and I am.

Skip
 
On the subject of lenses, I was quit delighted with the ease with which I can use my old manual lenses - some of which are superb. One needs to tell the camera what lens is mounted, shoot in aperture priority - which I do anyway - and they meter just fine. When first mounting the lens, select the "Non CPU Lens Data" item from the menu. A sub-menu shows three ranges so one need not page through dozens of focal lengths. Select the focal length and the widest aperture of the lens you are mounting.

In subsequent uses, when you select the focal length, it will remember the aperture making mounting quick. The Non CPU menu item will also show on the Recent Settings menu, which also cuts mounting time.

I was worried about the focusing screen, since most dSLRS regard the screen just as a viewing screen. There have been many reports of difficulty in focusing manual lenses. There is a third party replacement screen, but so far I have had zero problems focusing the D200. It also has a green LED as an "electronic rangefinder" that glows steadily when the lens is perfectly focused.

My f-2.0 24mm lens produces low contrast. I was never very happy with the lens on film, and it probably sets up reflection feedback between its real element and the sensor. The 28mm PC-Nikkor is an early one and the manual said it should not be used. However, if one enters the f-stop at which one plans to shoot, it works well as a super-sharp semiwide-angle lens. The shift does not work well at all.

All other lenses work fine. The 35mm f-2.0 becomes a very sharp normal lens. It also works perfectly with my Pentax Stereo Photography attachment, doing stereo pairs without vignetting. The 55mm MicroNikkor an 82.5mm macro-capable all around lens. With the fast aperture of the 105mm f-1.8 now functioning as a 157mm lens, it is very easy to isolate a subject from both foreground and background. The 200mm f-2.8 becomes a fast 300mm lens.

I needed a super-telephoto a long time back to compress perspective, filling the whole frame with the signs of Las Vegas for a travel magazine. As luck would have it, Perkin Elmer had set out to create the ultimate 600mm telephoto, which the marketed through Vivitar as a Series I. (Perkin Elmer also built the Hubble Space Telescope.) It is a mirror lens that is almost solid glass, so can not go out of alignment.

I had rarely used it after the assignment, but have been having a blast with it on the D200, where it is now a 900mm in effect. Using the middle of the image circle, the images are amazingly sharp. Of course, a high shutter speed is needed - even off a monopod - and focus is critical.

Finally, I dug to the bottom of the box and came up with a neat lens I bought a very long time ago. It is a soft-focus lens from Spiratone - not sure if they are even still around. It is basically just a 100mm focal-length magnifying glass with every kind of aberration one could imagine, on a simple focusing mount. Works fine and I used it for some informal portraits over the weekend that came out quite nicely. I think it cost all of about $25US at the time I bought it.

So with the reservations above, the manual lenses that have been gathering dust for the past half dozen years are back in service. As top-notch primes, their performance is little short of stunning when it comes to sharpness and detail.

larry!
http://www.larry-bolch.com/
 
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