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New photography article online.
mgoodm3
Posts: 17,497 ✭✭✭
Same link as my sigline. I made a "lighting shootout".
coinimaging.com/my photography articles Check out the new macro lens testing section
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mgoodm3
Posts: 17,497 ✭✭✭
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Good information.
Thanks!
peacockcoins
But I think you are wasting valuable time. Don't you have some coins to image?
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etexmike
Twitter
Ken
In the article, you say:
At this point, I still haven’t figured out why I was getting inconsistent results with the white balance on both the fluorescent light and the Ott
light.
One reason for inconsistent results with fluroescent bulbes is that they are actually turning on and off (at 60 cycles/second, IIRC). With shutter speeds in this neighborhood or faster, you will get strange color shifts due to the flashing nature of fluroescent lighting. [edited to add you talk about this later in the article]
Another reason for this shift could be that fluroescent bulbs shift color spectrum according to how long they've been on (you seem to arrive at this conclusion too) -- this is a fact. This can usually be seen best for the first few seconds after you turn on a bulb, but happens for a longer period of time than you can easily see.
Take care...Mike
<< <i>Great article. Thanks for sharing.
In the article, you say:
At this point, I still haven’t figured out why I was getting inconsistent results with the white balance on both the fluorescent light and the Ott
light.
One reason for inconsistent results with fluroescent bulbes is that they are actually turning on and off (at 60 cycles/second, IIRC). With shutter speeds in this neighborhood or faster, you will get strange color shifts due to the flashing nature of fluroescent lighting.
Another reason for this shift could be that fluroescent bulbs shift color spectrum according to how long they've been on. This can usually be seen best for the first few seconds after you turn on a bulb, but happens for a longer period of time than you can easily see.
Take care...Mike >>
You must read on farther than you did, my friend. I make the same points later in the article.
<< <i>You must read on farther than you did, my friend. I make the same points later in the article.
I got so excited that I was going to let you in on something, I couldn't wait. I should've known.
Get as much light bulb wattage as you can, the faster shutter speeds will pay off in sharper pictures. This is mainly an issue at larger image
sizes.
Why do you say this?
IMHO, a good tripod, remote shutter release, and shutter delay will all make a much greater impact on the sharpness of a photo than amount of light / shutter speed. In fact, unless there is a shortcoming in your equipment, shutter speed will make no difference whatsoever...Mike
Again, excellent work Mark....Mike
<< <i>In the article you say:
Get as much light bulb wattage as you can, the faster shutter speeds will pay off in sharper pictures. This is mainly an issue at larger image
sizes.
Why do you say this?
IMHO, a good tripod, remote shutter release, and shutter delay will all make a much greater impact on the sharpness of a photo than amount of light / shutter speed. In fact, unless there is a shortcoming in your equipment, shutter speed will make no difference whatsoever...Mike >>
i was only talking lighting in the article. i go into that kinda stuff in my main article.
Even with the sturdy setup I have now, i can see small differences in sharpness with faster shutter. It's small, but a real factor.
Does it make a difference what lighting you use for gold coins? Do you have a reflector behind the bulbs or use the bulbs naked?
Thank you!
Rgrds
Tom
Coin's for sale/trade.
Tom Pilitowski
US Rare Coin Investments
800-624-1870
Dang this light thingy...... I started out with softwhite to reveall to Par30 flood to florescent to reveall, which I've been usuing as of late. I think I'll try the PAr 30's again.
So you like the "greycard"........my copystand base is grey, will that do for setting white balance??
Herb
Greg Hansen, Melbourne, FL Click here for any current EBAY auctions Multiple "Circle of Trust" transactions over 14 years on forum
Very nice work and thank you for the article.
Jonathan
I was thinking about getting an Ott light until I read your paper on lighting. Following your guide, simply by using a bright soft white bulb close to the camera my pictures have improved dramatically.
Still I would think that an Ott light would have several advantages. It's lots cooler, the light is more diffuse, and it's closer to "white" than an incandescent bulb.
White balance is off: paper background looks yellow. IrfanView doesn't fix WB, so I will either have to look for freeware that does, or figure out how to do it on the camera. It's possible, according to the user manual.
My camera has a macro setting, but 5" is about the closest the camera will still autofocus. At this distance a small cent occupies about 1/4 of the vertical height of the image. Can zoom in, but then have to compensate by backing up, so no net gain in pixels.
Have to be careful to hold the camera exactly parallel to the plane of the coin, or else one edge of the coin ends up slightly out of focus. A tripod or stand should help. Doesn't seem to be any motion blur though.
Blow-ups are still a bit jagged - I mean pixellated, not grainy. Brighter bulb does help - I guess it makes the shutter speed faster.
For a cheap 6.3 Mp point-and-shoot, the camera has a lot of flexibility. It can be completely automatic, or use shutter priority or aperture priority modes. Or manually set everything: aperture (f/2.8-f/4.7), shutter speed, exposure comp, ISO, WB, etc. Unfortunately I am a Compleat Idiot when it comes to photography so it will take me a long time to figure all this stuff out.
Some cameras have several fluorescent settings for wb. If it has a daylight fluorescent WB setting, you'll want to try that out.
This is great! In two quantum jumps, for zero cost, my pictures have improved more than I could have imagined. Thanks again.
But man that bulb really heats up fast. At 4 to 5 inches from a slab you definitely don't want to leave it on for long! I think I'll try an Ott twisty bulb.