Problems with my Sigma 150mm Macro

DaddyO

Purchased this lens used not too long ago and I am finding that more often than not
the images I am getting are soft / not sharp. Today I had time to mount it
on tripod and run around the house doing some test shots. I also
used a cable release.

I wonder if I got a bad issue of this lens? Frankly, I was expecting more.
:dunno

I"d be interested in hearing any thoughts you all might have.

My little test results showing the near original and then a crop from it.

#1 1/250, f13, ISO 800


#2 1/250, f13, ISO 800


#3 1/50, f13, ISO 800


#4 1/50, f13, ISO 800


#5 1/60, f10, ISO 1600


#6 1/60, f10, ISO 1600


#7 1/40, f10, ISO 1600


#8 1/40, f10, ISO 1600

courierman

yep they look soft,but now tell me what your setting are

this is a raw 1/320 f11 iso 100 canon 400D and the sigma 150 handheld like all my shots

DaddyO

courierman wrote:

yep they look soft,but now tell me what your setting are

this is a raw 1/320 f11 iso 100 canon 400D and the sigma 150 handheld like all my shots

Nice one.
Your image is exactly in the range of what I was expecting & to do it
hand held also.
Are you using flash / natural light?
Not sure how you got away with using ISO 100 @ f11.

EXIF data is saved in each image except the first. My firefox plugin isn't seeing it though. Thats nuts. Canon zoombrowser sees the info. Nuts again!

I will get the info together and post it by hand pretty soon. Michael

DaddyO

Camera settings now noted.
Have added camera settings for each photo for those of us who can't see the embedded exif data. Appreciate all the help. Thanks, Michael

Robinivich

I would expect sharper, the droplet on the leaf is particularly telling. Are you absolutely certain your subjects were all nice and still?

Before assuming it's a decentered or otherwise defective copy, try a shot with very high shutter speeds (1/2000+) at around an f/5.6 aperture (sunlight and ISO 200-400 should do it). Try a subject like newsprint. This should give a good maximum value for sharpness, and rule out technique, subject movement, and diffraction. If sharpness isn't awesome at these settings, then yeah, either return it or have it serviced.

DaddyO

Robinivich wrote:

I would expect sharper, the droplet on the leaf is particularly telling. Are you absolutely certain your subjects were all nice and still?

Before assuming it's a decentered or otherwise defective copy, try a shot with very high shutter speeds (1/2000+) at around an f/5.6 aperture (sunlight and ISO 200-400 should do it). Try a subject like newsprint. This should give a good maximum value for sharpness, and rule out technique, subject movement, and diffraction. If sharpness isn't awesome at these settings, then yeah, either return it or have it serviced.

Robinivich. Appreciate your note. Good points. I will put it to your test as
it will truly tell the story. Michael

courierman

ok your SS is to slow for the size of the lens ,try to keep it over 1/250, if your going to do macro you will need a flash all the macro shooters on here use a flash, at 1:1 with the hood off you can use the cameras flash

DaddyO

courierman wrote:

ok your SS is to slow for the size of the lens ,try to keep it over 1/250, if your going to do macro you will need a flash all the macro shooters on here use a flash, at 1:1 with the hood off you can use the cameras flash

Right. Flash needed. I have a 420EX. Will try it once I get into the manual
for macro efforts. Camera flash compensation on board camera is nice. 30D. Great flash for general shots.

You used flash for your spider picture? Your camera settings were interesting.
Low ISO and quick SS.
MIchael

courierman

yep i used a flash with this from Brian
http://www.flickr.com/groups/macroviewers/discuss/72157594312315664/

pieterprovoost

I'm a bit disappointed in my sigma 105mm as well, I'll try to make some test shots tonight, as Robinivich suggested...

pieterprovoost

pieterprovoost wrote:

I'm a bit disappointed in my sigma 105mm as well, I'll try to make some test shots tonight, as Robinivich suggested...

I have put the shots on http://www.pieterprovoost.nl/sigma Unfortunately, I had to use artificial lighting, so the exposure times are quite long. There are three images of printed text, and one of a dead mosquito. I have also uploaded two images of Trypetoptera, they are about the best result I get with this lens. In the html file you will find a few links to images which have the crispyness and texture that mine are lacking. Is it the lighting maybe? Or am I expecting too much of my lens?

FYI: I'm using a Canon 400D, a tripod and a remote control. No flash.

Thanks
Pieter

Lord Vetinari

pieterprovoost wrote:

I have put the shots on http://www.pieterprovoost.nl/sigma Unfortunately, I had to use artificial lighting, so the exposure times are quite long. There are three images of printed text, and one of a dead mosquito. I have also uploaded two images of Trypetoptera, they are about the best result I get with this lens. In the html file you will find a few links to images which have the crispyness and texture that mine are lacking. Is it the lighting maybe? Or am I expecting too much of my lens?

FYI: I'm using a Canon 400D, a tripod and a remote control. No flash.

Thanks
Pieter

Pieter , I suspect the lens is fine- certainly in the insect shots there are very sharp parts to the image.
I think you are shooting under difficult conditions with natural light giving wide apertures and therefore shallow DOF compared to some of the examples which I suspect are mainly flash shots.

You really need to try some shots in manual mode with flash 1/200th ISO100/200, F11 and manual focus.
Brian V.

pieterprovoost

Lord Vetinari wrote:

Pieter , I suspect the lens is fine- certainly in the insect shots there are very sharp parts to the image.
I think you are shooting under difficult conditions with natural light giving wide apertures and therefore shallow DOF compared to some of the examples which I suspect are mainly flash shots.

You really need to try some shots in manual mode with flash 1/200th ISO100/200, F11 and manual focus.
Brian V.

For the moment I don't have an external flash, and I have tried the internal one only once. That wasn't really a success because in Av mode apparently the exposure time does not change when switching on the flash (resulting in over-exposure). I will clear that out first, and then maybe make a few more test shots.

Although I'm not really happy with my images, I have to admit that - as you say - the details are there. I guess a ring flash would make the lighting a lot better, and the shooting easier...

By the way, your Osmia images are really amazing! I hope one day I'll be able to make shots like that.

Thank you
Pieter

Lord Vetinari

pieterprovoost wrote:

For the moment I don't have an external flash, and I have tried the internal one only once. That wasn't really a success because in Av mode apparently the exposure time does not change when switching on the flash (resulting in over-exposure). I will clear that out first, and then maybe make a few more test shots.

Pieter

Pieter- In Av or Tv modes you will only get fill flash - In manual mode you decide the shutter speed and aperture and the flash supplies the necessary light, so you get the flash as the primary light source.
Brian V.

TwistedJ

I returned my sigma and saved up for a Nikon. I have a Tamron lens giving me a fit now.