IR Lens Test – Sigma 18-35mm f/1.8 DC HSM Art Lens

I recently had the opportunity to test drive the Sigma 18-35 f1.8 Art lens.

It’s a great lens, but is it a great INFRARED lens?   

I’ve been told not bury the lead, so the answer to that question is a resounding YES!  During the short time I had this lens, I had the opportunity to test it on 3 different Canon camera bodies, 50D, SL1, and 7DMKII.  The results relating to Infrared were of zero concern.  No hot spots, no focusing issues.

I am not going to list off all the specifications and mechanical reasons why this lens is so amazing, if you want the specs, click here

Instead, I want to give you straight forward impressions and results.

When you take this lens out of the box, you immediately know this is Not a kit lens, and this is a serious piece of hardware.  It has a very solid, well constructed feel to it.  On the camera it has weight, but also has a balance to it.  I used this lens at one point on a Canon SL1, which is very small and light, yet it was not difficult to use.

Once you start using the lens you realize that if this were a car, you’d get lots of speeding tickets.  This lens is smooth and very fast.  The auto focus is quick and has no hesitation, and feels effortless.  There is one technical spec I have to mention; it gives you an f1.8 thru the full range of the lens,  this is the first of it’s kind according to Sigma.

 

So. let’s see what it can do.

First, I tried a flower in vase, simple white background, and used light coming thru a window.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

This was shot at 20mm  f3.5 for 1/5 sec  ISO 100.  Red and Blue color channels swapped.

The camera was white balanced prior to shooting, using the white background as a reference image, making certain there was direct light on the white background.  The image came out sharp.

 

Next, I decided to move out doors and see what I could do with that f1.8

Here’s a Tulip at 590nm, shot with a Canon SL1

 

 

 

 

 

 

 

 

 

 

 

This was made at 18mm f1.8 1/2500 sec ISO100.  The camera was white balanced prior to shooting using the grass in front of the image as a reference.  It was a little windy, but at 1/2500 sec you couldn’t tell.  I loved the softness of the background and visible texture in the petals.   Okay, I’m starting to get impressed.

Next, I decided to take the lens to photograph Butterflies.  If you’ve never tried to photograph butterflies, I highly recommend it.  The exercise will test your skills at shooting quickly.  I went to the Butterfly House at the St. Louis Zoo to see what this sports car of a lens can do.



Before walking in, I shot this landscape image.

 

 

 

 

 

 

 

 

 

 

 

Now I know this is not a terribly exciting image, but I took this check the lens for distortion at 18mm, and to check for hot spots at f22.  I am impressed, but now for the speed test.

After entering the Butterfly house, I selected a large leaf and used an image of it for my white balance reference.  I set the lens to f 1.8 and then adjusted the shutter speed on the fly.

 

 

 

 

 

 

 

 

 

 

 

 

 

This was shot at 590nm IR at 35mm f1.8 1/640sec ISO100.  The Red and Blue color channels were swapped.  The wings were moving as this was shot.

 

 

 

 

 

 

 

 

 

 

 

This is 590nm IR 35mm f1.8 1/640sec, ISO100.  The Red and Blue channels were swapped.  It is sharp.

 

Then as I was shooting, a butterfly decided to take a closer look at what I was doing and landed on my hand.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Remember how I said the lens had a good balanced feel to it?  This is why.  I moved the lens to it’s widest point then got my hand a far away as possible.  This is 590nmIR 35mm f1.8 1/400sec ISO 100.  This one I can prove I shot one handed.

 

So now I am impressed.  I have one last test image I want to try; a portrait.

For this image I utilized light coming thru a window and a white card reference image to set my white balance.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

This is 590nm IR 20mm f1.8 1/125sec ISO100  The results of this image to me were amazing.  This image required very little adjusting, and the sharpness of the image is impressive.  My only regret is the model had contacts in and they can be seen in the eyes.

 

So, The Sigma 18-35mm f1.8 is in my opinion an impressive lens that works well with Infrared photography. My thanks to Sigma for the loan.

If you are considering an art lens, this is the one that should get, . . . . but you should buy two.

I had to send the one they loaned me back, and my birthday is coming up.  Worth a shot.