An optical 'zoom' or 'variable focal length' lens is one that has a range of focal lengths at which it can operate. "Digital zoom" is a technology which simulates optical zoom by cropping the image.
33
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11answers
2k views
Is digital zoom really useful?
I've always wondered what is the use of digital zoom, apart from viewing the subject clearly on the LCD display.
We can take a photo with the optical
zoom and crop the photo to the desired
region of ...
19
votes
3answers
1k views
When you zoom in with a lens on an SLR why does the lens go in then out?
I guess this is more a question of optics than photography but I just got an SLR with a basic 18-55 lens. I noticed that when going from 18 to 55 or 55 to 18 the lens physically comes back in and ...
19
votes
4answers
1k views
What is focal length and how does it affect my photos?
What is focal-length? Are focal-length and zoom synonymous? How does the focal length of a photo affect it?
18
votes
5answers
25k views
How do I convert lens mm to optical zoom times?
What is the rule to convert the 'mm' notation to the 'optical zoom' notation? I searched a bit and found this one:
optical zoom = maximum focal length / minimum focal length
For example a 18-55mm ...
16
votes
11answers
5k views
What is the best lens for taking photos of birds?
I was using a Panasonic Lumix, now I finally got a Canon EOS 60D, but I was used to that 18x zoom that my old camera has, because you can't get too close from the birds to take pictures, since they ...
16
votes
3answers
2k views
Fast prime vs. expensive zoom for indoor sports photograhy?
I plan to try shooting my kids' indoor activities (Tae Kwon Do and Figure Skating). I can get pretty close to the action for TKD, and I have access to ice/board level positions for shooting at the ...
15
votes
6answers
1k views
Which scenarios are better shot with a prime lens versus zoom lens or macro lens?
What scenarios are better shot with a prime lens? A zoom lens? A macro lens?
15
votes
8answers
684 views
Would a prime be redundant with a fast zoom?
Now that I am finally getting a fast zoom (Tamron 17-50mm 2.8) I've been considering a fast prime to go with it, specifically a Sigma 50mm 1.4. Despite its shortcomings, it still does really nice ...
14
votes
6answers
458 views
Overlapping vs. Complementary lenses
I'd like to know if anyone has any advice or experience they can share about using a pair of zoom lenses that have overlapping focal lengths; or a pair of zoom lenses that have adjacent focal lengths.
...
13
votes
5answers
1k views
Why choose an 80-200mm over an 18-200mm lens?
Being a beginner, I can't see why I must choose an 80-200 over an 18-200. Are there scenarios where an 80-200 would be preferable over an 18-200?
I will be buying a D7000 soon and am looking at ...
12
votes
4answers
3k views
How can a lens like a 18-55mm have more than one focal length?
How can a lens have a range of focal lengths? Shouldn't it be a single number?
Isn't focal length supposed to be fixed for a lens of a particular shape and geometry?
What am I missing?
How many ...
12
votes
5answers
777 views
Why do we talk about focal-length when frame sizes are different?
I keep seeing people talking about focal-length of lenses without saying how large the frame is. Is there a more sensible way to talk about how much a lens “zooms”?
(I have seen so many adverts ...
11
votes
4answers
4k views
What's the advantage of buying a fixed 50mm f/1.8 lens when my camera has an 18-55mm zoom lens?
I've got a Nikon D3100 with an 18-55mm zoom lens. I'm keen to experiment with some other lenses and a friend of mine recently reccommended I purchase a fixed 50mm f/1.8 lens as he said it's good for ...
11
votes
2answers
1k views
Why push/pull zoom is not widespread?
The Canon EF 100-400mm f/4.5-5.6 L IS USM has a push/pull zoom mechanism instead of a zoom ring. Other lenses, like the Nikon 80-200mm f/2.8 AF released in 1988 use this type of zoom too, but the ...
10
votes
4answers
857 views
Is it problematic to mount a Canon EF 100-400mm f/4.5-5.6L lens on Rebel XSi (450D) body?
I have a Canon Rebel XSi (450D) and I'm going on a two week trip to Argentina and Patagonia where I want to try some wildlife photography. I have the kit 55-250 f/4.5-5.6 lens which I like, but I ...
10
votes
3answers
2k views
How does changing focal length affect depth of field?
I'm curious about how my "area of acceptable focus" changes when the focal length of the lens I'm using changes as I zoom (or switch lenses). In particular, I'd like to know how the front & back ...
10
votes
2answers
287 views
Max aperture on zoom lenses - stepwise or linear?
When zooming with lenses without a fixed max aperture, the change in aperture* that the camera displays is stepwise, usually in steps of thirds. But, is the max aperture really the same all the way as ...
9
votes
2answers
843 views
What is the meaning of W and T on a camera's zoom buttons?
On every conventional digital camera (excluding the models with detachable lenses), there are buttons to zoom in and out with W side and T side.
When you press W, the lens zooms out. The lens zooms ...
9
votes
5answers
647 views
Why do fixed lens cameras have a motorized zoom while interchangeable lens cameras don't?
I would like to know why motorized zoom (controlled by a W/T lever) is always on fixed-lens cameras and never on interchangeable lens cameras.
9
votes
5answers
663 views
What are the pros and cons of non-extending zoom lenses?
Apart from the obvious benefit of not changing the center of gravity, what are the technical pros and cons of zoom lenses that do not change "physical length" when changing the focal length?
For ...
9
votes
4answers
334 views
Why are some zoom lenses “soft” at either end of the focal length range?
As one reads about zoom lenses, a relatively common comment that comes up in reviews of some lenses (especially lower-priced lenses) is that the lens is not as sharp ("soft") at one or both ends of ...
9
votes
2answers
1k views
Why do zoom lenses and compact cameras have varied maximum aperture across the zoom range?
Why does a camera's maximum (allowed) aperture get smaller when you increase its zoom?
9
votes
2answers
2k views
What differences between point and shoot zoom versus DSLR zoom cause the price disparity?
I'm just getting into the world of photography, stepping up from a point-and-shoot. I've just purchased a Nikon D3100 and it should be here in a couple of days.
I've done lots of research, but ...
9
votes
4answers
260 views
What are important considerations when purchasing a zoom lens?
What should I be aware of when buying a zoom lens (other than that it will fit my camera)? What specs should I pay close attention to?
8
votes
4answers
4k views
What does 'how much zoom' mean?
I have Canon 18-135 and 70-300 zoom lenses. People ask me how much zoom my camera supports.
What am I supposed to tell them?
"135 ÷ 18 = 7.5" and "300 ÷ 70 = 4.2"?
8
votes
4answers
2k views
What is the difference between a telephoto lens and a zoom lens?
Looking at the product page for Nikon lenses, I notice a distinction between telephoto lens and zoom lens.
What is the difference between the two? Why would I want one over the other? I wiki'd ...
8
votes
6answers
248 views
On smaller prints, will a high-quality zoom lens provide near equal image quality compared to primes?
Let's say I shoot with Canon EF 35mm f/1.4L, Canon EF 50mm f/1.4, and a Canon EF 85mm f/1.8. Can these 3 primes be replaced with a Canon EF 24-70mm f/2.8 for the convenience of not needing to change ...
7
votes
6answers
5k views
How do I get the best results for sports with a 70-200mm f/2.8?
Can anyone help? I am using a nikon d7000 for sports photography. My husband kindly bought me a sigma 70-200mm telephoto lens 2.8 as I shoot a lot of low light indoor sports. I have only just started ...
7
votes
4answers
949 views
How to take sharp photos while using maximum optical zoom?
When I shoot with high zoom (above 3X on my point-and-shoot camera), the sharpness of the picture seems to come down. Is it a feature of all cameras or is it due to higher sensitivity to camera shakes ...
7
votes
5answers
267 views
Digital zoom versus optical zoom for minimising camera shake
Here's the scenario: every so often our garden plays host to some small deer. Naturally, I try to take pictures of them. From inside the house, I can get a decent shot with full zoom on my camera. ...
7
votes
5answers
668 views
How much different are the Tamron 17-50mm f/2.8 stabilized (VC) and non-stabilized versions?
I have seen these 2 lenses being suggested by many people across the site as general purpose zooms and an upgrade to the typical 18-55mm kit lenses. The price difference seems to be around $200 (~INR ...
7
votes
1answer
859 views
Why does the maximum aperture change with focal length? [duplicate]
Possible Duplicate:
Why do zoom lenses and compact cameras have varied maximum aperture across the zoom range?
It is rather common with zooms that the maximum aperture changes (in fact, ...
7
votes
1answer
355 views
Why is the Canon MP-E 65mm F/2.8 Macro Lens not called a zoom?
The Canon MP-E 65mm works differently than my other macro lenses. Compare:
With a standard 35mm macro, I can frame first and then adjust focus which only changes framing very slightly with.
With the ...
6
votes
4answers
473 views
Is depth of field and bokeh influenced by distance to the subject?
I know that the aperture size has a direct effect on the depth of field.
However, what about distance to the subject? Let's say I took two pictures, one at 24mm and one at 70mm, using the same lens ...
6
votes
5answers
1k views
Why is my Nikon 18-200 lens not focusing at higher focal lengths?
My Nikon 18-200 lens on a D300 camera will not focus when it is zoomed between 135mm and 200mm. Is there any tips on how to solve this besides handing it in to a photo store?
6
votes
3answers
323 views
Would a fixed or zoom telephoto lens be better for learning?
My daughter has a Nikon D-90 camera body and two prime f1.4 lenses 50mm and 35mm. She is interested in learning more, and I am curious which of a zoom or fixed telephoto lens would help her best? Is ...
6
votes
7answers
2k views
Which lenses are best for macro and for birdwatching (both Canon and Nikon)?
Now I have old Sony A100 DSLR + Minolta AF 24-50/4, Minolta AF 50/1.6, Tokina ATX 80-400/4.5-5.6, ...
My camera is old.
In near future I am going to buy new DSLR.
I think it will be Canon or Nikon. I ...
6
votes
1answer
188 views
When focusing at max zoom, focus is lost after zooming out. Is that normal?
On my Canon kit lens, I could completely zoom in, focus on the object and then zoom out to take the picture with the object still in focus.
Now I have a Sigma 18-200mm (with a Canon 600D) and that ...
6
votes
3answers
6k views
Canon kit with standard EF-S 18-55mm IS or 18-135mm IS?
I'm going to order a new Canon 550d in a kit with a lens. I'm fairly new to SLR photography which means I have not much knowledge about the difference between lenses.
There is an offer for a Canon ...
6
votes
5answers
4k views
Would the Tamron 18- 270 mm F/3.5-6.3 Di II VC PZD make a good choice as my second lens?
I have a Canon 50/f1.8. I am looking for a zoom lens. After much research, I have zeroed in two lenses as my second lens: either Tamron 18-270 mm F/3.5-6.3 Di II VC PZD or Canon EF75-300mm f/4-5.6 III ...
6
votes
5answers
319 views
Alternative/third-party superzoom for Nikon?
I have a Nikon 18-200 VR which I think is great. I often use the 200mm part of it so I'm thinking of an even more extreme superzoom, but I'm not familiar with other lenses than Nikon, but I have been ...
6
votes
1answer
156 views
How many moving elements in a Canon A490?
I got mugged a few days ago, but got my camera back in the end. Bonus: I got some sand too. I now have the camera in pieces, cleaning them as I go along, and the lens barrel extends and retracts ...
5
votes
7answers
2k views
How can I visualize or simulate the effect of different focal lengths?
I have seen many camera review sites illustrate the effect of using different focal lengths on the same photograph using frames. There are also similar illustrations to compare different sensors (full ...
5
votes
4answers
2k views
Between Nikon 18-55mm II and 50mm f/1.8, which suits my needs better?
I am an absolute beginner in serious photography. I'm a position to get a Nikon D70 body for $100 or so.
I've been researching lenses and I'm debating if I should get the one that originally came ...
5
votes
3answers
213 views
What differentiates a Canon standard zoom from an ultra-wide angle zoom?
I was checking the Canon website and found that the EF-S 15-85mm f/3.5-5.6 IS USM lens is a "standard" zoom lens, whereas the EF 17-40mm f/4L USM is described as an "ultra-wide" Zoom.
Is there ...
5
votes
4answers
747 views
Should I get a kit or separate lens for my D7000?
I am set on getting a D7000 and am drooling already to get one. My only hurdle left is to determine whether the kit lens is good or if i should get the body only and put the 300$ difference between ...
5
votes
2answers
638 views
Can't auto-focus at full zoom
I have a Canon 1000d, and the standard lens EF-S 18-55mm. Recently I was out taking photos and I've noticed that if I zoom in fully, the lens can't auto focus. I can still take shots using manual ...
5
votes
2answers
731 views
Tethering to Control Zoom on Nikon DSLR
Most Nikon DSLR have a tethered capture option, however I haven't come across any of them that controls the zoom of the DSLR.
I guess the zoom is controlled manually by rotating the ring on the lens.
...
5
votes
1answer
386 views
Should my flash zoom match my lens focal length or its 35mm equivalent?
I have a camera with an APS-C sized sensor. Should my flash zoom match my lens's actual focal length or its 35mm equivalent?
I am hoping that someone can shed some scientific light to this matter.
5
votes
2answers
847 views
Is there a Tamron 70-200mm lens which is optically superior to the Canon 70-200 f2.8 IS?
In the June 2011's Popular Photography magazine (Canada, hard copy, pg. 90) in an article titled "Star Power", on a one page overview of the Canon 70-200mm f2.8L IS II USM, the author (Julia Silber) ...
