Have a Pentax K2, KX or KM? Want to know what focusing screens were available for it? How about an MX? or an LX?
I’ve put together the following information from various sales brochures and manuals. Hope you find this helpful.
K-Series (K2, KX, KM) Focusing Screens
In addition to the microprism and split-image focusing screens, the following three types are available:
Cross-Microprism
The cross-microprism type is to be used with a high-speed lens. When used with a relatively fast lens, f/1.2 to f/2.8, this type of focusing screen improves focusing accuracy. (It is not suited for use with f/4 or f/4.5 lenses.)
Matte
The matte screen has neither cross-microprism nor split-image focusing spot. It is suitable for lenses slower than f/5.6.
Photomicrographic
The photomicrographic type has a cross-microprism spot surrounded by a Fresnel lens on the ground glass. the cross-microprism area is used for normal focusing. But when the image is dark and the depth of field is relatively small, the spot surrounding the central microprism is used.
Pentax MX Focusing Screens
*MX Screens can also be used on the LX*
Split-Image/Microprism/Matte SC-1
This screen is standard on the MX. It features a center split-image spot surrounded by a microprism collar on a matte background.
Microprism/Matte (SA-1, SA-3)
This versatile yet simple screen provides a microprism grid on a matte background. Model SA-1 is for use with normal lenses. Model SA-3 features sharper microprism angles for easier focusing with fast lenses (f/2.8-f/1.2).
Split-Image/Matte (SB-1)
For general applications, it features a convenient split-screen spot on a matte background.
Matte with Central Cross Hair (SD-1)
Perfect for scientific applications or macrophotography where lighting is dim. Screen features central cross hairs on an all-matte field.
Clear Screen with Central Cross Hairs (SE)
This all-matte ground glass screen is well suited for super-telephoto photography or situations where no distractions to composition are wanted.
Etched Grid Crosslines (SG)
This screen is very useful for aligning perpendicular lines in architectural photography in conjunction with the SMC Pentax 28mm Shift lens.
Scale Matte (SI)
An engraved scale on a matte field allows the macro photographer to determine image magnification and subject size while viewing through the finder.
Pentax LX Focusing Screens
Split-Image/Microprism/Matte (SC-21, SC-26)
This screen is standard on the MX. It features a center split-image spot surrounded by a microprism collar on a matte background. Model SC-26 is extra-bright for use with telephoto lenses.
Microprism/Matte (SA-21, SA-23, SA-26)
This versatile yet simple screen provides a microprism grid on a matte background. Model SA-21 is for use with normal lenses. Model SA-23 features sharper microprism angles for easier focusing with fast lenses (f/2.8-f/1.2). Model SA-26 is for use with lenses 300mm and over.
Split-Image/Matte (SB-21)
For general applications, it features a convenient split-screen spot on a matte background.
Matte with Central Cross Hairs (SD-21)
Perfect for scientific applications or macrophotography where lighting is dim. Screen features central cross hairs on an all-matte field.
Clear Screen with Central Cross Hairs (SD-11)
Central cross hairs are superimposed on a clear glass screen. Ideal for astronomical studies, microscopy or other applications where maximum light transmission is required.
Matte (SE-20, SE-25)
This all-matte ground glass screen is well suited for super-telephoto photography or situations where no distractions to composition are wanted. Model SE-25 is especially for use with lenses 300mm and over.
Etched Grid (SG-20)
This screen is very useful for aligning perpendicular lines in architectural photography in conjunction with the SMC Pentax 28mm Shift lens.
Scale Matte (SI-20)
An engraved scale on a matte field allows the macro photographer to determine image magnification and subject size while viewing through the finder.
Vintage Camera Digest 