Sigma 10mm f2.8 lens - test images

Will do Dave.

Intermittent cloud this evening so stayed in my back garden.
Took a 30sec snap of the ISS poassing by the Moon and the Pleiades.
skydrive.live.com/redir?resid=FD21544143...key=!AA9x_ng7AXke7gc

I had a look at the camera settings this evening.
This is all I could find.

400d:
Colour Spacer: sRGB or Adobe RGB. I have it on sRGB
Custom WB: Looks for an image on the CF card

300d:
Parameters: Parameter 1; Parameter 2; Adobe RGB; Set 1; Set 2; Set 3; Set up.
Custom WB: Looks for an image on the CF card

HI Michael

Custom white balance on a canon camera, its a bit tricky and i don't think necessary here, but what it is: you take a picture of a white sheet of paper under the conditions of your intended photo. then tell the camera that the photo is white. Useful in shooting food and products ect.

Under that menu there should be a few others, if you dont have one called colour temp (K) then turn on Tungsten light this is approx 3200k.

on colour space, always use Adobe RGB, its a much larger palette of colours than sRGB. all Cameras should be preset to Adobe IMHO.

Are you shooting in RAW format? I would recommend it as you can play with all of the camera settings after the shot is taken on the PC. Did you get Digital Photo Pro with your camera? Its a canon program.

would also highly recommend Backyard EOS, i lost mine when i changed laptop, must get it back.

Dave, There are no other menus in the camera wrt to colour temperature.

However, I have the software Imagesplus on my PC.
This allows the conversion of RAW files and changing their colour temp.
Below is a link to one converted to jpg with Tungsten.
skydrive.live.com/redir?resid=FD21544143...key=!AAoTzu21ZVluFKU

It's a touch heavy on the blue, but it sure is effective at removing the red.
Nice suggestion.

ok maybe these models dont have Kelvin.

the blue can be toned down in photoshop elements.

use a colour saturation layer, use the dropper to pick out the most blue area and then turn down that colour.

id love one a 10mm 2.8 myself, but i think a 70-200 is first on the list

manic_dave wrote: ok maybe these models dont have Kelvin.

The 400d doesn't by default anyway.

But as you pointed out just shoot in raw. White balance is then only done post processing.
Same for the RGB. If you care enough to need to use Adobe then you probably should be shooting raw in the first place.

The approach to take will depend on whether this is for taking pretty pictures or whether you want to be able to do say photometry for meteors or light pollution.

I'd like that lens myself. I have a 70-200, but would need something will full frame to really appreciate the 10mm I think.

Speaking of the 400d for astro, check out code.google.com/p/400plus/ . It gives you extended bulb (up to 100 minutes), intervalometer, and kelvin colour balance (though I've never tried that).

Is that the Russian Firmware fix Albert?

i was going to use it on my old 1100d but i sold it and got the 60d.

the 10mm on the crop sensor is still 16mm, which is still very wide.

I have read a bit on the samyang 8mm for canon, for 250 euro you can get a 12.8 on the crop. not bad for full sky shots.

is the 70-200 any good for astro shots. im thinking of it and an astrotrac.