Is there such thing as a ir variable ndreddit

Neutral density filters(ND) are one of the staple components of virtually every serious landscape photographers gear bag(read some outdoor photography tips). The great thing ND filters allow us to do is shoot longer exposures in bright light without overexposure. A good analogy I always like to use is that ND filters are light sunglasses for your lens. Neutral density filters are a great way to remain flexible with your shooting even when conditions aren’t ideal.

Many of us have looked though the eyepiece of a department store microscope and seen a fuzzy looking “something” with the highest magnification objective lens. It’s not completely surprising that an inexpensive lens would give a blurry image. There are many optical aberrations that need to be corrected to manufacture the expensive lenses that are used on research grade microscopes.

I was also pleased to note that both the stock lens cap and lens hood still worked perfectly while the filter was attached.

We respectfully acknowledge the University of Arizona is on the land and territories of Indigenous peoples. Today, Arizona is home to 22 federally recognized tribes, with Tucson being home to the O’odham and the Yaqui. Committed to diversity and inclusion, the University strives to build sustainable relationships with sovereign Native Nations and Indigenous communities through education offerings, partnerships, and community service.

The “cost” of obtaining a higher NA is that the working distance (WD) of the lens becomes much shorter. Working distance is “… the distance between the objective front lens and the top of the cover glass when the specimen is in focus. In most instances, the working distance of an objective decreases as magnification increases.” (1) A smaller working distance can be a problem when you cannot see an object with a high magnification lens, even though you could see it with a low magnification lens. A 10x objective can have a WD of several millimeters (4-10mm, or 4000-10,000um). A well corrected, high NA 20x dry objective will have a WD of slightly less than 1mm (1000um). Most well corrected, high NA 40x and 60x oil objectives have working distances on the order of 0.1mm (100um).

Numerical Aperture (NA) is “… a critical value that indicates the light acceptance angle, which in turn determines the light gathering power, the resolving power, and depth of field of the objective.”(1) As light passes through a sample, the information describing the highest resolution information in the sample is diffracted at a very wide angle. Low magnification lenses typically have low NAs, meaning that they cannot capture the highest resolution information. To capture the widely diffracted information, high NA lenses move the front of the lens closer to the sample (increases the light acceptance angle). Dry lenses can only have NAs of up to 1.0. By using specially formulated oil and oil lenses, NAs of up to 1.4 can be achieved.

Reviewed & updated 06/16/2017. Creation of this web page was originally supported as part of the Southwest Environmental Health Sciences Center at the University of Arizona, NIEHS P30 ES006694.

The fitler itself is well made, looks great, and lends itself to relatively respectable performance for a filter costing around $20US. Beginners will love it for its quality to cost ratio and even experienced photogs could find a place for it in their kit. The K&F Concept 58mm ND Fader Variable Neutral Density Adjustable ND Filter is a low cost option for those looking for a variable ND filter with good performance in the 1-4 stop range of light reduction. The diminished performance at the far end of the filters capabilities are indicative of the cost of the product and expectations should be tempered with that information in mind!

Adam has also authored one of the most comprehensive guide books on using Adobe Lightroom Classic CC.  You can get your copy of Lightroom Mastery: A COMPLETE GUIDE TO WORKING IN LIGHTROOM CLASSIC CC HERE!

As I mentioned earlier, there is most often an unavoidable compromise between cost and quality(with a few exceptions) when it comes to camera gear. The K&F Concept variable ND is a budget ND filter currently retailing for around $20US from both Amazon and Kentfaith.com. The performance of the filter was a mix of great to, well, not so great. When used at it’s lowest optical darkening setting, the results were wonderful for a filter at this price point.

For a $20 ND filter, I was honestly surprised at how well the filter performed up till now. And from a real world point of view, the filtration offered between ND2 and ND400(1-8 ⅔ stops) was outstanding. This lends me to believe that he overall results from this filter are perfectly workable from approximately 1 to 3-4 stops of darkening. Here are three more images showing the progression of image quality across the range of filtration. It’s interesting to note that while the last image shows significant quality reduction, the massively apparent purple tinting observed in the previous example is virtually nonexistent. This is possibly due to the lengthy exposure of 25 seconds used for the image above. The white balance of my camera was set to ‘Auto’.

Moving a little darker to approximately 3 stops of light reduction, the results were still great and allowed me to shoot long exposures with no real color tinting or vignetting to speak of from a practical standpoint.

The world leader in infrared conversions, modifications & DIY IR conversion tutorials. Scratched sensor replacement, UV & Full spectrum conversions.

Neutral Density Filter

Given the low cost of this variable ND filter from K&F Concept, I have no problem with the limited performance results achieved from my tests.

The UArizona Microscopy Alliance is a volunteer and collaborative effort to bring information about shared microscopy facilities to the University of Arizona and the community.

Like most photographic equipment, you often get what you pay for…. That doesn’t mean that every piece of budget gear isn’t capable of yielding great results. The K&F Concept 58mm ND Fader Variable Neutral Density Adjustable ND Filter is quite a mouthful to say, but essentially it is a neutral density filter that is capable of shooting at various shades of darkening. This particular filter ranges from ND2-ND400. If we’re speaking in terms of f-stops, then it equates to 1-8 ⅔ stops of light reduction. The version I tested was the 58mm size and I used it with my trusty Canon EF 50mm F1.4.

Photo maker, author, and adventurer currently based in the western portion of his home state of Tennessee. You can usually find him on some distant trail making photographs or at his computer writing about all the elegant madness that is photography. Follow his sometimes controversial Blog on everything related to photography and then check out his cozy home on Instagram.

Now, moving onto the darkest setting of ND400, or approximately 8 ⅔ stops, we see some extreme problems arise in terms of color tinting and image degradation.

Copyright © 2024 Life Pixel Infrared - All rights reserved - LifePixel Infrared Photography IR Conversion, Modification & Scratched Sensor Repair

A volunteer and collaborative effort to bring information about shared microscopy facilities to the University of Arizona and the community.

The filter arrived well packaged and included a nice micro-fiber cloth along with a standard padded plastic filter case.

Overall, I was extremely impressed with the build of this ND filter from K&F. The material of the two elements is listed by the manufacturer as “optical quality glass” with the body of the filter likely being aluminum. Originally I had thought the housing was made from some type of resin but after a scratch test it turned out to indeed be metallic.

Neutral density filter laser

The filter itself functions by turning the outer ring to the desired darkening setting is reached. This ND filter functioned extremely smoothly with no binding or sticking points.

High magnification without high NA does not give the resolving power that most people expect from a research grade microscope.  Using a high NA objective lens means that you are most likely sacrificing working distance (how deep into the sample that you can focus) for higher optical resolution. In most instances this is a very acceptable trade off.

Filed Under: Gear Tagged With: Canon, filter, filters, K&F, landscape photography, Lifepixel, mountain photography, nd filter, neutral density, Photographer, photographers, Travel photography, Wildlife photographer

Light microscopes can, under the best conditions, resolve objects that are approximately equal to half the size of the wavelength used. In the real world this comes out to objects that are 250-300nm in size, if you are using a NA=1.4 objective lens (under optimal conditions). This means that you can make out two adjacent objects in this size range, assuming that you can see at least a 25% dip in intensity between them (Rayleigh criterion). Sample preparation is especially important when you want to resolve structures this small.