Scientific Experimentation!

I finally got a chance to experiment with my manual prime lenses on the Pentax istDL DSLR. It took a little doing but I think I’ve figured out how to make it work.

What you see here is a shot of Gandalf the Grey on top of my old truck taken with the 50mm, f1.7 lens set at f2.8 on the “istDL.” When a manual lens is mounted this camera it apparently sets itself up in aperture priority mode (unless you set it to manual mode) and in this case matched a 1/500 shutter speed @ ISO400 to my f2.8 aperture for the exposure.

There are apparently some other things you can do to affect and perhaps improve the outcome. In manual mode for instance, you can set everything yourself. Controlling the ISO setting (using a slower speed) would likely result in better quality photos too, and I am planning some more experimentation to flesh those things out but my first attempts weren’t too shabby. 

The biggest issue is focusing.  The istDL has a neat feature for use with a manual lens. It will allow you to push the shutter button half way (just as you do with a fully automatic lens) and as you slowly turn the focusing ring it will signal you when it thinks your picture is in focus.

This only works about half the time since the camera uses contrast-detection AF based on some kind of averaging algorithm. When I was shooting wide open (shallow depth of field) it seemed to invariably focus on the wrong spot. Of course this could just me my inexperience with the process too! It is not impossible to focus manually using the matte screen but not nearly as easy as with my SLR’s which have the split screen assist.

I have long said that I would be willing to switch to digital completely if I could ever find a DSLR that just worked like my 35mm SLR but with a full sized digital sensor instead of the film. Clearly we are not there yet but I am optimistic that we will get there eventually.