How big are Messier objects in pixels?

Now I am getting some more experience with some of the brighter Messier objects, I decided to have a look at the catalogue and see how bright and how large some of the objects are – basically what I can expect to see in my telescope. All the copies of the Messier catalogue floating aroundContinue reading “How big are Messier objects in pixels?”

Angle of view on various formats

I’ve probably discussed before the way that different size “sensors” (or pieces of film) need different focal length lenses to achieve the same angle of view. For instance, it is well known that a 50mm lens on an APS-C crop-sensor DSLR behaves a bit like a 75mm lens on a 35mm full-frame camera. I’ve extendedContinue reading “Angle of view on various formats”

Negative area

There’s a really useful diagram on Wikipedia that shows the relatives sizes of different digital camera sensors. But it doesn’t include medium format film – so I made my own version. Format Typical use Size Area Crop factor APS-C Most consumer DSLRs and APS film cameras ~22x15mm 330mm² 1.5-16× 35mm Professional full frame DSLRs andContinue reading “Negative area”

Focal lengths on different formats

Consumer photographic lenses are almost always sold by their focal length when used on a 35mm camera (or full-frame professional DSLR). It’s already confusing enough to work out what their effective focal length is when used on an APS-C sensor (most consumer DSLRs), but since I’ve been getting into medium-format photography it’s even more confusingContinue reading “Focal lengths on different formats”

How many megapixels do you get from film?

Well that’s a question. There’s no easy answer, but I’ll discuss it a little here. If you just want the figures, scroll down to the table! The number of film “pixels” (grains) does not equal to the resolution of the film – unlike pixels on a digital sensor. For now let’s ignore this fact andContinue reading “How many megapixels do you get from film?”