JPEG/TIFF Image Size & Quality

The 995 offers two more resolution options (1280 x 960, 1600 x 1200) over what was already available on the 990. This means the 995 now provides 20 possible combinations of image size and quality (plus 512 x 384 in Multi-16 continuous mode and 320 x 240 in Ultra-HS continuous mode). The HI (TIFF) mode is only available at 2048 x 1536 or 2048 x 1360 (3:2).

Standard Test Scene

To give an impression of what some of the combinations of image size and quality produce the table below is a cross reference of some of them:

• 2048 x 1536 HI (TIFF)
• 2048 x 1536 FINE
• 2048 x 1536 NORMAL
• 2048 x 1536 BASIC
• 1600 x 1200 FINE
• 1280 x 960 FINE
• 1024 x 768 FINE
• 640 x 480 FINE

Images below are cropped 240 x 100 area of the image magnified 200% (nearest neighbour).

	2048 x 1536
HI TIFF	9,327 KB (Not available for download)
FINE JPEG	990 KB
NORM. JPEG	677 KB
BASIC JPEG	329 KB
	1600 x 1200
FINE JPEG	595 KB
	1280 x 960
FINE JPEG	460 KB
	1024 x 768
JPEG FINE	293 KB
	640 x 480
JPEG FINE	122 KB

As you can see there's very little to gain from shooting TIFF (and plenty of space to lose) but it's there for the purist shooters. Otherwise JPEG artifacts increase as we'd expect, 2048 x 1536 NORMAL is managable and doesn't really produce to many artifacts. The new 1600 x 1200 and 1280 x 960 sizes are very welcome and will be very useful for those shooting for the web / cd-rom publication / monitor slideshows only.

ISO (Sensitivity) Adjustment

ISO equivalence on a digital camera is the ability to increase the sensitivity of the CCD to allow for faster shutter speeds and/or better performance in low light. The way this works in a digital camera is by "turning up the volume" on the CCD's signal amplifiers, nothing is without its price however and doing so also amplifies any noise that may be present and often affects colour saturation.

The 995 features four selectable ISO sensitivities of 100, 200, 400 and 800 as well as the same Auto mode we saw on the 990 (which appears to vary sensitivity between ISO 100 and 200 depending on available light). The ISO 800 setting is new to the 995 and appears in red on the LCD monitor when selected to warn of the potential of excessive noise.

Good light (10 EV)	Low light (3 EV)
ISO 100, 1/58 sec, F3.1	ISO 100, 1.0 sec, F3.6
ISO 200, 1/91 sec, F3.6	ISO 200, 1/2 sec, F3.1
ISO 400, 1/151 sec, F4.0	ISO 400, 1/4 sec, F3.1
ISO 800, 1/198 sec, F5.1	ISO 800, 1/6 sec, F3.1

Noise levels seem noticeably lower than the 990, and this is an improvement over the original pre-production 995 we used. Noise levels at ISO 100 are very low, even ISO 200 is usable with only very slight chroma speckling. ISO 400 noise is relatively low and manageable, ISO 800 could be used in extreme circumstances (and assuming you'll be cleaning / downsampling the image).

Enabling Noise Reduction has no effect on ISO noise, it is designed to be used only for long exposures to remove "hot pixels".