Improve Techniques Yield Improved Images (I Hope)

I don't see a place to post images to be evaluated for imaging techniques.
I'm not after opinions about the coin.
I'm after opinions about the quality of the images.






The coin is graded NGC AU-53.

 

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It shows really nice detail, but the color seems off judging by the color of the slab prongs. And nice coin, even though you don't want the opinion.

 

Ooooo, good observation.
Actually the coin's image color looks reasonably close to reality -- depending on what lighting I hold it under.
I'll have to try getting the holder insert close to white and see what the coin looks like then.

 

Nice job. I agree on the color, it seems a bit on the cold/blue side. Also I've found that using a very soft touch on sharpening the image helps. Here's a version I adjusted.

 

It might help in evaluation if you gave the technical data also.

 

Good point.

CAMERA: Nikon D90
LENS: AF-S Micro Nikkor 60mm 1:2.8G ED
LIGHT: OTT LITE 13w White
SETTINGS: Aperture Priority f5.6
SETTINGS: Manual Focus
BACKGROUND: Dark gray, non-reflective
FILE TYPE: JPEG Fine

One thing I haven't done is adjust the white balance.

 

Nice equipment and coin.

 

I just checked my White Balance and it's set to "A" (auto).
I'll probably let it stay that way unless I start getting unappealing results.

 

Very nice photo overall - I was going to say that the white balance looks like it may need a tweak, but you beat me to it.

I've had some "interesting" experiences with white balance in the past and found that I would always get the results I wanted with manual white balance, but that also depended on the camera. With a single reference for white balance and as consistent lighting as possible, you can take pictures weeks apart and have almost undetectable differences. I found that more difficult with auto white balance, but, again, it seems to vary somewhat with the camera make and model.

 

I agree with @Dave M on the color being a tad bit cold/blue. Not so terrible with a coin like this, but if the coin had some color it would make a larger difference.

I also can't tell if the image is slightly out of focus, or if that's just the resolution of the image. What are you using to stabilize the image, and are you using the infrared remote that Nikon sells for this camera (to eliminate any unnecessary camera shake?)

Does the coin in hand have underlying luster? I'm not so sure your lighting has fully captured it.

Personally, I would shoot in RAW if possible (and if you have the software to edit them that way.) This takes a bit more time and a lot more memory, but gives you a lot more options for adjusting your images.

Also would be interested to hear your shutter speed/ISO settings.

All this being said, I think your images are highly above average if you're selling the coin on eBay.

 

Since I'm using Aperture Priority the shutter speed is whatever the camera decides with the light source I'm using.

But ISO is a different story.
I just came back from a vacation in which I was often changing the ISO.
I have no idea what it is at the moment (checking).
ANSWER: 200 (and I believe that is very good under the current circumstances).

 

Aw rats!
New fly in the ointment.
The half dollar was easy to image because it's large and I can see it well through the viewer.
But now I tried a half dime and I have focusing problems.
I saw this before but wrote it off as carelessness but now I think it's my eyes (I'm 73 and wear trifocals).
I suspect a greater depth of field will solve the problem.
I'm shooting at f5.6; I think I'll up that to about f7.1.
That will result in a slower shutter speed so I'll go to ISO 400.

Testing! Testing! Testing!

 

If that doesn't do it, consider this:

http://www.amazon.com/Nikon-Eyepiece-Magnifier-Digital-Cameras/dp/B00009R8ST

nice diopter range for us visual-challenged scientists

 

Gee the Internet is fun
I'm trying to get a definitive statement about desertgem's link.
It appears I'll need the DK-22 adapter to fit the eyepiece magnifier to my D90.
Fortunately if I go ahead and get the adapter it won't cost much (~$5).
But it will be a pain if it's not the right item.

Getting an answer is a trip.
Nikon swapped me from Live Chat to e-mail (no answer yet).
Most other places want you to register.
All I want is an answer to one question; I don't want to join a site to get it.

 

Set aperture at f/8 and forget it. That will maximize the available depth of field, the lack of which at f/5.6 might be convincing you is a focus problem. Apertures narrower than f/8 will be diffraction-limited and cost you sharpness that way. Give autofocus a shot as well - I've no Nikon experience but I've had multiple Canon combinations using their 100mm Macro and not even slabs fooled its' autofocus.

Your D90 will provide professional results at least to ISO400 and likely ISO800. ISO is not the concern with digicams it was 10 years ago; noise-reduction routines in camera and postprocessing software are far more sophisticated these days. This will help exposure times. As long as you're not triggering the shutter manually, you can go as slow as 1/8 or even slower and still get a stable shot.

Which leads me to the solution to your visual challenge - tethering software so you can run the show from your keyboard/mouse and focus onscreen rather than in that tiny LCD (a problem for me and I'm 15 years younger than you ). Nikon does not offer the free tethering software which Canon does (did?), but there are a couple possibilities far cheaper than Nikon's $180 version, Camera Control Pro 2:

Camera RC: full-feature 30-day trial, $20 to own.

TetherPro from Oxford Eye, currently $24.99

ControlMyNikon (not completely compatible with the D90 unless they've updated)

I'm not linking because I don't know the convention around here; Googling the name of the software will bring it up.

After all that, there are yet more improvements to be had via shooting RAW, but that's an additional layer of learning which ought to be added onto the knowledge you gain from these questions; it's probably counterproductive to learn it simultaneously.

 

SuperDave, thanks for your comments and suggestions.

After shooting 4 half dimes at my current settings I'm confident that it's my manual focusing that's the problem.
The resulting images were quite varied with regard to focus.

I've had trouble in the past with autofocus; that's why I do manual now.
Autofocus often would image the scratches on the holder but the coin would be blurry.
I blame that on depth of field, especially when I was using f4.5 or wider.
For a while it was so bad, even with manual focus, that a coin's center was nicely done but the rim area was blurry.
That's when I figured out I was WAY too close to the slab; the geometry was the culprit.

I do one other thing that I haven't mentioned yet.
I restrict the point of the light meter reading to the center of the coin.
That affects the exposure time and I think makes the image close to real for the coin.
I don't want other lighting (such as from the whitish insert of an NGC slab) to affect the exposure.

As for RAW, I'll leave that for the REAL pros.
That format creates huge files and is best for further editing.

 

Keep in mind that the automatic metering on cameras is set to adjust the exposure assuming the image is an average of 17% gray. So with your technique, if the center of the coin is about 17% gray, then it may work. That may be fairly close for a silver coin, but for gold, bronze or copper, it will not be right.

 

Just for GP's, here''s the one half dime I managed to focus right:





It may not be perfect but it's close enough for me.

 

One trick you could try is manually-focusing the lens roughly where you want, and then clicking the focus switch to Auto and triggering the shot. It might give the lens a hint as to which plane you want it focusing on.

 

Does The D90 have 'live view' Kanga? I use LV to help focus my photos.