testing out my new lens...

vonnagy · Apr 5, 2004

having a bit of fun with my new 15-30mm sigma lens:

i am going to take it back 2morrow.. see that red dot on the stairs? well its on all the time exposures. normal shots are fine. but i just tested it with a perfectly clean lens and its still there :cry: I've paid enough for it!

manda · Apr 5, 2004

i didnt evne notice the dot but Mark....

THESE ARE STUNNING!!!!!!!!!!!!!!!!!!
I think some of your best yet.
If thats the lens talking, bloody hell!

The colours are insane.

terri · Apr 5, 2004

Beautiful stuff, as usual Mark..... what's up with the red dot showing on time exposures...? :scratch: That is definitely NOT ok.... What kind of troubleshooting have you performed?

voodoocat · Apr 5, 2004

Beautiful shots Mark.
The first one is a bit dark, but the colors are amazing.

vonnagy · Apr 5, 2004

Beautiful stuff, as usual Mark..... what's up with the red dot showing on time exposures...? That is definitely NOT ok.... What kind of troubleshooting have you performed?

oi, its in the camera, i've just went and discovered it in my photos. because the quality of my tamron lens is not as sharp as as this one, i went back to some of my older photos and found it in the same cooridinates. ugh!!

After scrutinising several pictures from both my tamron and sigma lenses, i think I may have to have the camera's sensored cleaned :cry:

Oh thanks for your comments folks, this new lens is super crisp, fast and the renders colours and contrast bewtifully.

Tammy · Apr 5, 2004

Hate it when that happens :x

Sorry to hear about your camera, but if its any consulation, when you get it cleaned looks like you got great work ahead of you with this lens... these shots are fantastic... the colors are so rich - everything around here looks dead

- and yes, I'm officially jealous.

photobug · Apr 5, 2004

Great shots Mark. Looks like a hot pixel, not something on the sensor. Does the 10D have dark frame subtraction (noise reduction) for long exposures? If so, it might make it go away without having to mess with sending it back.

If not, one pixel isn't hard to fix in PS. A PITA, but not hard.

mrsid99 · Apr 5, 2004

Really like that second one Mark!

Harpper · Apr 5, 2004

photobug said:
Great shots Mark. Looks like a hot pixel, not something on the sensor. Does the 10D have dark frame subtraction (noise reduction) for long exposures? If so, it might make it go away without having to mess with sending it back.

I was thinking the same thing when I saw it. I remember reading something about this awhile back so I did a google search. This isn't the same article I read but it does explain hot pixels. It also has a picture of almost the same red hot pixel as von's.

Apparently they come in several colors and it's a problem in all digital cameras but only show themselves in long exposures(more than 1-2 seconds).

Besides using photoshop to get rid of it, what photobug said about dark frame substraction sounds like the other option I've read. I don't know exactly how it works but from what I've read apparently some cameras have the option to take "dark frame" pictures to correct the problem. What you do is after taking the shot you also take a shot with the lense cap on with the same exposure time. The hot pixels will show up in the dark shot letting the camera know which pixels to delete or something like that.

Anyway, von, these are great pictures dispite the problem. Your second picture is simply amazing. A wide angle lense is perfect for that shot. Good work, von.