Pentax Optio RS1500 Review

August 1, 2011 | Matt Grayson |

Image Quality

All of the sample images in this Review were taken using the 14 megapixel JPEG setting, which gives an average image size of around 2.5Mb.

Let's put this in context right away that the Pentax Optio RS1500 is priced at under £100 and generally the lower the quality of the camera, the lower the quality of the pictures. But at low ISO, the RS1500 doesn't push out bad results. In fact apart from a bit too much sharpening from the processor, the pictures are good. We did detect a bit of noise at ISO 100 which isn't good news at all but it's only in really dark areas. The Pentax seems to work well up to ISO 400 where the picture quality will start to visibly degrade.

Colours are recorded realistically on the Pentax Optio RS1500 and it's a shame that when using a high ISO that the noise discolours the images so much. At low ISO, primary colours are bright and saturated while more forest colours such as dark greens and browns are rich. The camera is sympathetic enough to more subtle hues and can also realistically record more difficult colours such as purple.


If it wasn't for the small amount of noise in the darker areas of photographs at low ISO settings, the RS1500 pictures are pretty good. Edge definition is sharp and there's loads of detail in finer areas. It seems that the RS1500 has an unusual noise reduction facility because we found that in our tests, coloured noise we saw in the ISO 100 pictures has disappeared in ISO 200 pictures. There's more salt & pepper noise in the black parts of a picture giving smooth textures a mottled effect but as the tones get lighter, the image quality improves.

The image quality only really visibly degrades at ISO 800 and boy does it ever. Shadows and dark colours have a purple cast over them as the noise to signal ratio gets closer and the processor boosts both. Edge definition is still clear but showing signs of failing and as the settings increase the problem exacerbates. In a bid for damage control, the camera drops the resolution of the picture to 5 megapixels at ISO 3200 and picture quality does get slightly better but at the final ISO 6400 setting, quality is really bad.

ISO 100 (100% Crop)

ISO 200 (100% Crop)


ISO 400 (100% Crop)

ISO 800 (100% Crop)


ISO 1600 (100% Crop)

ISO 3200 (100% Crop)


ISO 6400 (100% Crop)



The sharpness of the pictures from the Pentax Optio RS1500 is good enough for general viewing but we did find that adding some standard sharpening in an editing suite such as Adobe Photoshop CS4 helped.

Original (100% Crop)

Sharpened (100% Crop)

Chromatic Aberrations

We found only rare cases of chromatic aberration in the pictures we took with the RS1500. A lot of cases we found we suspected of being lens flare more than chroma but at the times we did find it, the camera handled it well.

Example 1 (100% Crop)


At this point, we normally cover how awesome the macro is and how – when a camera has super macro – it gets even better. Well, the Pentax Optio RS1500 gives a comparably deflating performance. The normal macro system has a close focus of around 15cm which is less than decent. Super macro sounds like the RS1500 will pull its shirt open and spin around in a phone box to provide much closer focusing. Some cameras provide point blank range or thereabouts but the RS1500 has a rather tepid 8cm.

However, the quality of the pictures in macro is good, the pictures are sharp and clear and although the lens loses definition towards the edges of the frame, it's not too bad and compares favourably with other cameras in this price range.


100% Crop


The Pentax Optio RS1500's built in flash does add a degree of vignetting to pictures at wide angle although this is only minor. The vignetting remains through to full telephoto although it's not as discernible. We couldn't find traces of red-eye with or without the red-eye reduction on the camera. It's enabled in the flash functions opened by pressing the left side of the navigational pad. Continuing to press this button scrolls through the options and there are four in total. It's also possible to force the flash on, force it off and set it to auto.

Flash Off - Wide Angle (

Flash On - Wide Angle (27.5mm)

ISO 64 ISO 64

Flash Off - Telephoto (110mm)

Flash On - Telephoto (110mm)

ISO 64 ISO 64

And here are some portrait shots. Neither the Flash On or the Red-eye-Reduction settings caused any red-eye.

Flash On

Flash On (100% Crop)

Red-eye Reduction

Red-eye Reduction (100% Crop)


The Pentax Optio RS1500 has a dedicated night shot mode and using this, the camera selects a high ISO which is unfortunate because in our test even though it was only dusk, the camera still chose ISO 800. It would be nice to have a night shot with tripod setting to use a low ISO but you won't find it on the RS1500.


Night (100% Crop)

Shadow Correction

The Pentax Optio RS1500's shadow correction feature attempts to preserve more detail in both the shadow and highlight areas of an image.