Helicon Filter v4.50
Imaging - Imaging


Most are probably not aware of a RAW converter by Helicon though some may remember a pretty decent noise reduction toolkit from the company. Prior of this review I actually never tried the application and was quite surprised about the provided features rivaling and sometimes even exceeding those from the more well-known players. It is also by quite a margin the most affordable product within the scope of the reviews - the Pro version costs a mere 40US$ inc. free updates. There's also a free version with a (significantly) reduced feature set. Apart from a stand-alone version the Pro version can also blend into Photoshop as a plug-in.

Here's a how the development user interface looks like ... (click on the image for an enlargement):

Workflow Concept

Unlike most other RAW converters Helicon Filter doesn't really offer an image browser with organizational functionalities. You can either choose individual files for processing or select an (thumbnail-)image from a folder view. It takes quite a while for the application to generate thumbnails when opening a image folder for the first time. An image rating or marking is not provided. However, you can add images to a batch processing queue.

After selecting an image the application performs a RAW import in the true sense giving you a more or less unprocessed view to the image. From here on you can tune the image in 9 suggested processing steps though you're not enforced to take advantage of all of them. Each step has a dedicated purpose like noise reduction, brightness control, sharpening etc. The number of tuning option is pretty extensive - you can even limit the effect of e.g. noise reduction to a certain color range. The speed for the final file export is comparatively slow so if you want to process a number of images it is a good idea to add modified image to a working queue and run a batch job on this queue once you're finished with all your images (the application is blocked during a batch run).
The application remembers intermediate processing results so you can pick your work again whenever you want.

Processing Controls

Basic ExposureYes
Auto ExposureYes
Tone CurveYes
Lateral Chromatic Aberration (CA)No
Purple Fringing (PF)Yes
Auto Lens Flaw CorrectionNo
Distortions / Perspective Yes / Yes
Rotate / CropYes / Yes
Noise ReductionYes (good)
White BalancingYes
Color SaturationYes
Color VibrancyNo
Hot Pixel Detection/MaskingYes (via mask/map file, plus sensor dust mapping)
Photo OrganizationNo (only batch processing)
Import Formatsmost RAWs, many other formats
Export FormatsJPEG, TIFF, JPEG2000, PSD, PNG

Conversion Results

Helicon's sharpening is decent without being stellar. You can sharpen "fine details" as well as "edges". One problem of the algorithm is the rather pronounced generation of sharpening halos. There's a "suppress halo" check-box but you can either choose between some sharpening halos ... or more of them. Consequently Imatest found the result to be slightly over-sharpened even based on a soft approach.

Here's a 200% portion illustrating the halo effect of Helicon's sharpening (set to "moderate sharpening"):

You can easily go for more conservative sharpening settings with a lesser degree of halos than in the sample above though. As differentiator to other products you can limit the sharpening effect to a certain color range. Helicon refers to this as an "Equalizer" which also indicates that you can also define the weight of the effect per color.

As to be expected regarding its historical background the noise reduction works really well. If activated the default noise reduction seems quite aggressive loosing quite a bit of details but you can naturally choose more conservative settings. Similar to sharpening the Color Equalizer is also available here. For a typical landscape shot you could for instance apply a very aggressive for blues (e.g. sky) and marginal noise reduction for greens (e.g. trees). Additionally you can also fine tune the degree of noise reduction in highlights (typically little if any NR) and shadows (more NR). The principal noise reduction may be somewhat inferior to NoiseNinja (as used in Bibble) but if you take advantage of all the tuning possibilities you should be able to get some very good results from the product. Within the same workflow step it is also possible to mask out hot/dead pixels as well as sensor dust - you have to provide a mapping file (a mask).

Similar to SilkyPix it is also possible to correct lens distortions, perspective and vignetting via an all-manual but quite straight-forward process. A quite unique feature of the product is the correction of purple fringing (though they call it CA). Funnily they do NOT offer a lateral CA correction which is present in virtually all competing products (which usually do not offer PF correction). Well, you cannot have it all I guess.

The naming convention is also slightly different in the brightness processing step. The "Gamma" control is comparable to the usual exposure handling (Contrast is another control in case you wonder). "Exposure" either shifts the white point to the left or expands the histogram to the right - a bit weird actually and maybe a bug in the tested version. Anyway, combined with the build-in highlight and shadow control this works out pretty well. Following the general philosophy of the application it is possible to change the color characteristic either globally or selectively on a defined color range.


Helicon Filter is an interesting product which provides a zillion possibilities to tune your images. The most interesting approach is probably the Color Equalizer which is available for some of the processing steps. For most users the Equalizer is probably excessive but if you're really into fine tuning the tool is a wonderland for you. Another strength of the product is the quality of the noise reduction which is no surprise because that's where the company came from after all. On the downside the sharpening doesn't seem to be overly sophisticated (halos) and lateral CAs cannot be corrected (unlike purple fringing).

Disclosure: When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission. Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network and Google Adsense.