Using Pentax SLR lenses on a micro four thirds camera

Although we got rid of the majority of our Pentax gear over a year ago, I still have a few lenses.

Since these are just gathering dust, I thought I'd try to put them to use...

...so I bought a lens adapter!

DSLR optical path: where is that spec of dust?

After a recent trip to Hurst Castle we noticed dirt spots on the photos from 2 cameras.

While giving them a clean, it occurred to me that there are quite a few places where dust and dirt can be a problem.

Spots on my photos

Although a few spots on a photo can be fixed by running the image through your favourite photo editing software, the source of the problem should be investigated.

If you use a DSLR, black spots are most likely caused by dirt directly on the surface of the cameras sensor.

I've noticed this problem with photos taken on my Pentax K-30 during the last few months, but only just found the time to take a closer look.

Pentax K30 + Sigma 17-50mm F2.8 EX DC HSM

A few days ago I took possession of a new Sigma zoom lens.

It is essentially a replacement for the Pentax DA 18-55mm AL lens that people often buy bundled with a Pentax DSLR.

So here are a few comments on the Sigma with a simple comparison to the old Pentax.

Photography: #1 Exposure Explained

When you make the transition from "point and shoot" to SLR photography, there is one very important subject you really need to get to grips with:-

      ***   Exposure   ***

 

Using an SLR camera in "manual mode" puts you in total control, not only of composition and focus, but also exposure.

When you take a photo, you allow light into your camera. Assuming you are using a "digital" camera, the light reaches a "photo-sensitive sensor" which produces an electrical output, and ultimately this is processed into a picture. If this picture is correctly "exposed" it will not be too dark or too light.

"So what's the problem..." I hear you say,  "...if its too dark or light I can just use the Gimp or PaintShop Pro to adjust the brightness?"

The problem is that you will lose detail if your initial photo is too dark or too light. Adjusting the brightness will not recover that lost detail.