begging opinion

on photo quality..thank you in advance
dermot

Hi Dermot,

"photo quality" means a lot, but suppose you want to upload the image to Mindat, hmm...

Correct me if I got something wrong.

You use a 12 MP P&S camera made in 2010, which gives one an idea of what to expect in terms of sharpness, noise and colors. The camera can only do autofocus and produces jpeg images.

The photo looks as if the specimen was placed under normal light bulbs. The whitebalance is not quite right, it is still too yellow.
I guess it was a hand held shot, and because you do not want it "motion blurred" under the low light you have increased the ISO setting so much that the image gets noisy.
The original shot (in full resolution) must actually be very noisy, because even downscaled to the actual size it is still well visible.

The most disturbing part for me is the background, though. Not only is a background like the one in the photo not really visually pleasing and distracts from the specimen, it also interferes with the color of the mineral.


So if I got the "hand held shot" right, I'd suggest 2 things:
1. get a tripod, there are small ones (20 - 30 cm) that can be put on a table
2. use low ISO, but longer exposure (perhaps the camera will try to know better than you)
3. get a neutral background, white, gray, black and any dark color will hardly interfere with the color if the mineral
4. do a proper whitebalance (also easier with a white/gray background)

You've asked for it ;)



Edited 1 time(s). Last edit at 11/27/2011 09:57PM by Amir C. Akhavan.

I can actually tell you more:
ISO 800 (way too high for a camera like that)
Exposure Time 1/40, set automatically (doesn't matter on a tripod)
F 3.1 (might be too low, insufficient depth of field)
White Balance: Day White Fluorescent, set manually

I'd try ISO 100 or lower, higher F, different white balance

hi Amir thank you for your time and opinion..i am hoping too learn more
best wishes
dermot

I made this 24X17 inch box and used a drawer for the glass. I put the camera on a tripod and place the camera looking down on the mineral specimen. I dont put the camera level with the specimen becuase you can see the back edge of the glass. I do not use lights just the cameras flash. What I dislike about the glass is it gets scratched very easily. If you can use your flash on your camera the front of the specimen wouldn't be in the dark and the light would not be reflecting off the background.

may i ask if a mineral id..may be possible from either of these photos..?.
the colour is off..
thanks in advance

Pyrite encrusted fluorite?

thank you Reiner..best wishes

its great information...

I'll add some additional poor man's advice.

If you have limited control over the white balance on the camera, you can usually get the levels you need by using a DayGlo incandescent bulb which you can buy at the market or drug store. They aren't the ideal color temperature but they're better than ordinary incandescent bulbs.

If you can't get the exposure quite right, try placing the specimen on a neutral colored or two toned background (such as black and white). This forced the camera to choose a moderate value.

Photoshop. If it's more affordable to you than a better camera and set up, it's rather good at correcting for the short comings of cheap cameras and wrong color temperature lighting.