# Tag Info

### How does crop factor affect perspective?

When I started photography, this one took me ages to figure out, because people tend to explain it with a lot of math, or in a way that makes sense once you already grasp the principle but not before. ...
• 23.4k

### Confused about T-stop number. Does it account for crop factor?

Crop factor has nothing to do with T-stop. T-stop is strictly about light transmission which affects exposure. If a lens could be 100% transmissive the T-stop and f-number of the lens would be the ...
• 176k

### How do I calculate the difference in lens reach between a superzoom compact and a DSLR zoom lens?

Assuming that the quoted 1365mm focal length is in 35mm full frame equivalent terms (because otherwise, it would be huge), then the actual focal length of the lens assembly is around 1365 / 5.6 ~= ...
• 5,158
Accepted

### Can I use a 127.5mm focal length on a crop camera to see what the view would be like using an 85mm full frame lens?

No. You should set your zoom to 85mm to see what an 85mm lens looks like on your camera. The focal length of a lens is a physical property that does not change no matter what size sensor you put ...
• 52.5k

### APS-C crop factor 1.5x or 1.53x

Nikon 1.5X APS-C sensors in their current lineup are actually 1.52-1.53X depending on the exact measurements of the various different sensors in different models. Some older, discontinued models in ...
• 176k
Accepted

### How do I calculate the difference in lens reach between a superzoom compact and a DSLR zoom lens?

In photography, what is interesting is mostly the angle of view (AOV). The AOV is the angle that a lens offers on a sensor - it can be specified horizontally, diagonally, or vertically. ...
• 6,478
Accepted

### Should I quote focal length using equivalent focal length in a photobook?

The "equivalent" focal length draws from history, namely how it relates to a 35mm film camera, and there should come a time (and I think it is past) when we move on. The focal length IS the focal ...
• 2,363

### How does crop factor affect perspective?

Not correct. Perspective (referring to the size and spacing of background objects relative to subject) is determined by only the distance of camera to subject. This is the geometry drawn from the ...
• 12.9k

### How do I calculate the difference in lens reach between a superzoom compact and a DSLR zoom lens?

Based on others' calculation that you would need approximately an 850mm lens - which is not going to really be in any normal person's budget, nor even really portable - see the humorous article The ...
• 23.4k
Accepted

### Using FF lens on APS-C changes lens aperture value?

Neither the focal length of the lens nor the aperture of the lens change if we change the size of the sensor. What does change is the angle of view and the depth of field, but not the exposure. (We ...
• 176k

### How to achieve a normal 50mm look with a Nikon APS-C camera?

Do I buy a DX 50 mm or get the FX 35mm? That's up to your preference. Will they have the same effect? No. A 35mm FX lens or a 35mm DX lens will have the same effect with your camera. A 50mm FX lens ...
• 176k

### Confused about T-stop number. Does it account for crop factor?

The f-stop is a simple ratio. It is the focal length divided by the working diameter. We use this value to compare the image brightness of one lens vs. another. The f-stop is often in error because it ...
• 39.4k

### APS-C crop factor 1.5x or 1.53x

It doesn't really matter, but two decimal digits is more precision than is practically useful. ... or is it standard practice to round to only the first place with crop factor? This is good ...
• 143k
Accepted

### What's the equivalent of a 85mm portrait lens on Sony A6500 (APS-C)?

Well, sort of. There's no such thing as absolute equivalence. In terms of angle of view a 55mm lens will give the same AoV with a 1.5X APS-C sensor as an 85mm lens on a 36x24mm FF camera. In terms ...
• 176k
Accepted

### Can a focal reducer be used with a teleconverter?

Theoretically, optically, it would work (for low-quality values of "work"). Yes, the focal reducer would give an extra stop of light. But because the 2x teleconverter is responsible for 2 stops of ...
• 33.1k

### Why don't my calculations based on a crop factor of 1.5 work for the Nikon P1000?

It is simply that the P1000 does not offer an APS-C sensor - as its manual and marketing site state it has a 1/2.3" sensor, which offers a crop factor of ...
• 6,478
Accepted

### Why don't my calculations based on a crop factor of 1.5 work for the Nikon P1000?

The P1000 unfortunately isn't an APS-C, it's far smaller at 1/2.3-inch, which gives it a crop factor of 5.6. Compared to a 35mm sensor it is tiny. From ApoTelyt.com - Nikon P1000 Comparison Review ...
• 23.4k
Accepted

### Why doesn't full frame have faster shutter speed than crop (all other things equal)?

A full frame sensor gathers more light for the total area, but that's because there is more total area. The light gathered for the same sized portion of the recording medium is the same for any ...
• 143k

### Does it make sense to buy a Sigma Art f1.4 for a crop sensor body?

However, if I understand correctly the aperture need to be multiplied as well, which results in an f2.1 and means I am losing at least an f-stop. In short: No. If you use a FF-lens with an APS-C ...
• 292
Accepted

### APS-C crop factor 1.5x or 1.53x

You are correct. Like most manufacturers, Nikon APS-C sensor sizes vary depending on the camera model. Nikon crop factor can be 1.52, 1.53, 1.55, or 1.56 A list of the most common crop factors for ...
• 12.3k
Accepted

### Does crop factor affect light meter readings?

No, the light meter reading (for example, ISO 100, f/11, 1/200 second) already applies to any camera, any sensor size, any crop factor. That''s the beauty of the "f/stop" numbering system. Crop ...
• 12.9k

### Does it make sense to buy a Sigma Art f1.4 for a crop sensor body?

You will never lose any transmission stops (low light ability) using a smaller sensor, unless something behind the camera mount severely constrains what reaches the sensor (unlikely with general ...
• 7,232
Accepted

### Is it beneficial to use a crop sensor camera with a full frame telezoom?

By using an APS-C camera with higher pixel density, you will get "more pixels on the subject" than with a FF camera with lower pixel density. Sometimes that can be a good thing. There are many ...
• 176k
Accepted

### Do medium format lenses have a crop factor?

Crop factor is a characteristic of the camera, not the lens. A 50mm lens is 50mm no matter what you attach it to. The bigger or smaller sensor is what leads to crop factor, which is the ratio of the ...
• 5,158
Accepted

### FOV on an APS-C and Full frame 'lens'

Field of view is the real-world angle captured on the image. It is determined by the quotient of the sensor size and the focal length. That's basic geometry. If you want to keep the angles when ...
• 1,294

### Is it like an 18-55 DX lens on a DX body effectively equivalent to 27-82?

The way I understand crop-factor is that a 12mm lens mounted on an FX body will provide the same field of view of an 18mm lens mounted on a DX body, provided the distance between camera and subject ...
• 52.5k
Accepted

### Canon APS-C: what is the maximum sensor size EF-S lenses are designed to support?

The diagonal of the 70D 22.5x15mm sensor is 27.04mm. The diagonal of the 700D 22.3x14.9mm sensor is 26.82mm. That's a difference of less than 1%. The smallest APS-C sensor Canon has released is 22....
• 176k

### Why don't lens manufacters just label their lenses in 35mm equivalent terms?

A mm unit does NOT describes the field of view. A mm unit on a lens is a focal leingth. It does not matter if you project it on a "full frame" camera, dx sensor or a sheet of paper. But ...
• 25.1k