The Katz Eye™ focusing screen for the Pentax *istDL is a laser matte with a horizontal split prism circle and a microprism collar, very similar to the one you’d find in many classic SLRs. The split prism with microprism ring is a great combination for focusing in a variety of situations. The screen will have NO effect on the functioning of the autofocus sensors of the camera and it is a direct replacement for the original. This Katz Eye™ focusing screen is only for use with the *istDL camera. For other models in the *istD series, please see our Pentax section.
Viewfinder Markings The standard Katz Eye™ screen for the Pentax *istDL does not have the focus area brackets marked like the original screen - we prefer the clean look on the screen. For those users that wish to have the focus area brackets marked, this is available as an option. If you want the AF area markings, please be sure to select the focus area bracket pattern when adding the screen to your cart. The original spot metering circle cannot be shown due to its coincidence with the prism, but corresponds roughly to the diameter of the split prism. All other viewfinder information is unaffected by the installation of the Katz Eye™ screen.
Metering Information The Katz Eye™ focusing screen for the Pentax *istDL shows only a minimal effect on metering. Based on an analysis of the histograms, centerweighted average metering mode can be expected to be within 1/3 f-stops (factory tolerance) when using any AF lens. In full frame evaluative mode, meter readings will also be within 1/3 stops. Spot metering mode will also be accurate when using lenses with a maximum aperture of f3.5 or faster. Slower lenses will show a shift toward increased exposure in spot metering mode. The shift only occurs with slower lenses and can be managed by either using a different metering mode (evaluative or centerweighted) or by setting exposure compensation based on the histogram of a test shot.
The “Plus” Prism The Katz Eye™ focusing screen for the Pentax *istDL is is available exclusively in the Katz Eye™ “Plus” version. The “Plus” version has a unique prism design which delays the prism ‘blackout’ phenomenon until well after f11. Ordinary split prisms will black out by about f5.6, rendering them difficult to use with slower zoom lenses, teleconverters, or in extreme macro photography... but not the Katz Eye™ “Plus”. More information about the Katz Eye™ “Plus” can be found here.
Installation
While the Pentax *istDL is not advertised as having interchangeable focusing screens, the screen can be changed by most users and the process is not very involved - no modifications or calibration are required and a tool for handling the screen will be included with your purchase. A detailed insruction guide with high resolution color images will be provided with your order.
If you don’t feel confident installing the Katz Eye™ screen, your local camera shop should be able do it for you. Since the Katz Eye™ screen is a direct replacement for the original, any competent shop should be able to handle the installation and the original screen can be reinstalled at any time, should you so desire. If you want us to install it at Katz Eye™ Optics, we can, though it’s not the normal procedure. Please see the Installation Service page to order installation with your focusing screen. Installation service at Katz Eye™ Optics costs $65, plus the cost of return shipping of your camera.
Brightness Enhancement
Like all screens made by Katz Eye™ Optics, the Pentax *istDL screen can be OptiBrite brightness enhanced for the ultimate appearance. The OptiBrite treatment showed no effect on the light metering of the *istDL in our testing. Click here for more information about the OptiBrite treatment.
Grid/Crop Lines
In addition to the AF area brackets, the Katz Eye™ focusing screen for the Pentax *istDL is available with grid patterns or crop lines. We have a variety of standard patterns available or we can provide a custom pattern to your design. Click here for more information about our grid/crop line patters. Please note, that if you choose the AF Area Brackets AND an additional gridline pattern, the two will be combined in an aesthetically pleasing way and will appear different than the drawings shown.
All Katz Eye™ focusing screens are custom made to order and are usually not available to ship the day the order is placed. As of 07/09/2008 production is backlogged due to very heavy order volume and most orders are being completed in approximately 2 weeks from the date the order is placed.
