DSLR
Camera lens filter is a thin piece of glass that fixed or screwed on to the front end of any camera lens. It acts as a filter to lights that going through the cameras’ lens. There are many different types of lens filters in the market. Most of them are invented way back in the film photography era. While they are probably one of the most important SLR’s elements when you are shooting films, most of them are less significant if used with digital SLRs. However, less significant doesn’t mean useless. There are still occasions or conditions when lens filters become handy. How about travel photography? Are lens filters important enough to become an essential item in travelers’ packing list?
I’m going to share my views here the importance of various lens filters in DSLR for travelers who shoot uncountable travel photos on their holiday. There are currently four (4) main types of photo filters available in the market, namely UV, Polariser, Neutral Density, and Colour filter. They exist since those old days when we shot only film. Let’s see how each one of them performs in today’s digital photography.
- UV Filter – This filter is important since old days as films are sensitive to UV lights which can cause a picture looks hazy and blurry. Hence, UV filters are invented to cut down the Ultra Violet light spectrum from going through the camera lens and then the film. However, image sensors of today’s digital cameras are less receptive to UV light. Together with special coating on the latest lenses that help reducing UV lights, UV filters have become a less than critical element in digital photography nowadays. Instead, they act as a lens protector more than a filter.
- Polarizer filter – They work by reducing the amount of reflected light that passes to your camera’s sensor. Similar to polarizing sunglasses, polarizers will make skies appear deeper blue, will reduce glare and reflections off of water and other surfaces, and will reduce the contrast between land and sky. Polarizers are filter to visible light reflection so they are still important in today’s digital photography. They make your photos more vibrant than the actual scene you see, so they are creative filters.
- Neutral Density (ND) filter – ND filters are simply a darkened piece of glass to reduce the amount of lights entering through your lens into image sensor. The degree of darkness normally indicated as code numbers, such as Hoya’s ND2 means reducing light by 1 f-stop and ND4 by 2 f-stop. It is useful to reduce strong natural sunlight hence reduce the shutter speed or increase the Aperture of your camera setting to achieve identical exposure. Situations where ND filter is handy when you need to capture smooth flow effect of waterfall or ocean movement, or when you shoot portraiture with reducing Depth-of-Field. Again, this is a creative filter for capture something which your eyes won’t see and your post editing software can’t achieve.
- Colour filter – It could be cooling, warming or specific colour filter. It basically changes the White Balance of an actual scene, to either correct or create an unrealistic color cast. It is useful for film but not digital photography. Any digital camera currently including phone camera has this White Balance feature. They act the same way. Better still, digital WB setting can be fine tuned to your liking and it doesn’t need an extra piece of glass obstacle in front of your lens. So forget about it if you are shooting digitally. Check out my post on how to adjust your digital camera’s White Balance setting.
>>*Some in-depth explanation on camera lens filter can be read on Cambridge in Colour.
Do we need any of these lens filters in travel photography? The only filter we need to bring along is the UV filter. Travel photography is all about capturing what you found interesting on travel. UV filter will marginally improve the colour contrast and saturation of a photo to match what you see in actual. More importantly, for digital photography, it provides protection to the front element of your more expensive lens. It should be attached to all your lenses at all time. But bear in mind that lens filter, though is thin, adds an extra layer to your lens. This could harmfully affect the quality of lights or reduce lights that enter into your DSLR image sensor, hence, affect your image quality. So make sure you get the best quality UV filters in the market. Hoya HMC UV filters are a good start.
(A good example of travel photo taken with only UV filter attached but still matched what I’ve seen in actual scene)
Other creative filters such as polarizers, ND or colour filters are not essential in travel photography. Unless you wish to create some artistic effect to your travel photos, these filters can be kept at home, with only one exception. The only time you will need them, especially polarizers or graduated ND filters, is when the best lighting or best time to photo cannot be planned or hoped for, or my LEICA 5-steps theory can’t be followed. Hence polarizers or graduated ND filters can be used to salvage some of the bad colour cast from bad weather or to enhance the vibrancy of colour found in a dull scene.
– Travel Feeder, your ultimate travel photo guide.
One of the most overlooked but critical issue of our DSLR is a dirty image sensor. We tend to neglect the effect of a dirty sensor or, like me, always thought that image sensor will not get dirty easily if I change lenses carefully and set my camera’s internal sensor cleaning function to work frequently. I thought a dirty sensor would definitely be the last problem to face since I didn’t get any problem with my old Nikon D60 after 2 years of shooting. I was wrong! I got a seriously dirty image sensor of my Nikon D7000 after just one month of shooting!
Look at this photo below that I shot towards sunlight with small f20 Aperture:
Can you see those tiny dark spots in the sky? This is the evidence of a dirty DSLR’s sensor. What is a dirty image sensor of a DSLR? Image sensor is a light sensitive panel device in all Digital cameras that acts like the retina tissue lining in our eye balls. It transforms analog light signal to digital data that will then be calculated and reproduced images. When any dust, pollens, or any object falls and sticks on the low pass IR filter in front of the image sensor ( a dirty sensor actually refers to a dirty Low Pass Filter in front of the sensor), tiny dark spots will appear in your photos, and you have just got a dirty image sensor! However, it is only apparent when you shoot photos with smaller Aperture, such as f20, as deeper Depth-Of-Field will reveal clearly any dirt on the sensor. The above photo show you how dirty is my D7000′s image sensor! Take a closer look at those tiny dark spots that spread all over the place!
I zoomed into the same photo to let you see more clearly on those dust or pollen accumulated on the sensor. I did not realize this until I shot some sunburst photos on top of Jungfrau mountain of Switzerland, when I stopped down my camera’s Aperture to f20. I really got a shock! Oh My God! What had happened to my D7000? Did my DSLR’s sensor expose too long to direct sunlight? Have sun beams just damaged my camera’s sensor? Are they dirt? How could my D7000′s sensor be so dirty after only few months of shooting while I did not have this problem with my old D60 after 2 years? Are they condensation under freezing temperature? Are they permanent? There were too many questions circulating in my mind.
Dirt accumulation does not depends on your camera’s age. It depends merely on how you handle your camera and how you change your lenses. Changing lense more frequent means higher chance of dust sneaking into your camera’s body. I normally changed lenses very carefully. I always face my camera downward when changing lenses and I’ve been doing this since my D60. There haven’t got any dust on my D60′s sensor, why my D7000 had more than a dozen of them? I think I know why.But sadly only after my Europe trip…
Ever since DSLR manufacturers incorporated Live View and video recording function into their latest DSLR, they have also deliberately introduced a second gateway for the dust! Whenever you shoot still photos or video in Live View mode, your DSLR will keep the mirror flipped and locked up to let lights go into image sensor for as long as you wish to. This process has also opened the gate of a camera’s body access for other unwanted objects, such as dust, dirt, pollen or hair to sneak into the heart of a camera, which is the image sensor device! It will get even worse when you shoot with a long zoom lens. When you pull your lens or zoom out, you have, at the same time, pumped external air into your camera! If you shoot in Live View, you are actually pumping air directly onto the image sensor! This was why my Nikon D7000′s sensor was so dirty after only a few months of shooting while my old Nikon D60 hadn’t got this issue even after more then 2 years of shooting!!
So now you know that having a dirty image sensor is very easy nowadays, especially when you use zoom lens and always shoot in Live View mode. The lucky thing is that we can still take photos with a dirty sensor, as long as we set the Aperture no smaller than f3.5, or keep shooting in wide open Aperture. However, the unlucky thing is that we would not know our sensor is dirty until we shoot in small Aperture, for me, for day and night landscape shots, or sunburst shots, and it would be too late to know by then! We can not do any thing about it on site or on travel, unless we wish to risk ourselves for damaging the delicate image sensor by cleaning it ourselves in dusty outdoor environment! REMEMBER: Nikon has put a disclaimer clause in most of their DSLR’s User Manual that cleaning of the image sensor should be done by Nikon Service Centre. In Malaysia, cleaning a DSLR’s image sensor by Nikon Service Centre is fast and relatively cheap. It can usually be done in 15 minutes for a cost of RM20.00 if your camera is still under warranty and RM60.00 if it is not. You should check your local Nikon Service Centre for actual cost and time needed.
Conclusion? Make sure you check your DSLR’s image sensor a couple of weeks before each photography travel for its cleanliness. You can do this by shooting bright sky or well lit plain colour wall with small f22 Aperture. Any dirt or particles stuck on the sensor could be revealed clearly in the photo. You will still have enough time to send in your camera for cleaning by specialists. The cost and time for cloning out those dark spots in your images in post processing is definitely much much more than that of cleaning the image sensor before each travel! I have it very well experienced recently with my D7000 on my Europe Travel MkII, which had even spoilt my photo taking mood!
– Travel Feeder, your ultimate photo travel blog
Happy 100th Anniversary of international Women’s Day! Today, the 8th of March, is a big day for all women. All ladies, girls, daughters, mother, sisters or who ever female in this world are celebrating on this day to recognize themselves as an important person playing an important role in various sectors in our social, economical [...]
I have recently posted a White Balance setting explained for DSLR write-up on my photography blog. For those who are still wondering what is White Balance and why it exists in digital cameras, check it out now before you find out that your travel photos are all lacking some eye-catching elements. Why setting White Balance [...]



















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