focal length tags

[allypuk]

Hi all

I am new to DPS and after looking through alot of the photos espeically those in the weekly assignment sections. I have notice that the info attched to the photos contains the focal length when the photo was taken. My question is, I have bought a 4/3rds camera and believe that the focal lengths are double that of a 35mm, so are the focal lengths attached to the photos, for that camera or do they all relate to a 35mm camera, Or am I getting all mixed up ? Knowing this would help me am I am trying to work out my focal lengths when shooting and the effects they are having, but have been doing lots of reading and what to make sure when i practise something am i suppose to be doubling or 1/2 focal lengths. I hope you can understand what I mean here.

If someone could shed some light for me here i would be most grateful thanks

Ally

Don't worry about how your focal length relates to other cameras...just put the actual focal length that you used. If you want to add the crop factor, I don't think anyone would mind.

For instance, if I shot something at 50mm on my Canon T1i (1.6 crop factor), I say my focal length was 50mm, not 80mm.

[dcclark]

Agreed, just tag it with the number on the lens -- everyone has standardized on using the 35mm-equivalent lengths, not on the "converted for your crop factor" lengths.

I personally don't even tag my photos -- I mean, unless I'm using a prime, I have a whole continuum of lengths to use (and that info is encoded in the EXIF data anyhow), so it could get kinda confusing.

[RichardTaylor]

Canon cameras Exif info; the focal lengths are the real ones.

[allypuk]

yes dcclark it could get confusing easily, and thank you for your speedy replies,

When reading up on photography and they quote focal lengths I take it these are quoted 35mm cameras and as I own a 4/3rds camera I am to remeber the double rule for my camera type, Or do books etc tend to just qoute for the camera which took the shot and not to worry about it to much,

Another reason I ask for example is, if a weekly assignment was for say 50mm or as close as, do i need to apply my rule of double as I use a 4/3rds camera,

sorry if going on about it but newbie and just trying to keep all this new informatiobn straight in my head

thabk you all very much

Ally

[dcclark]

Yes, basically every book (and web site) I've seen will quote focal lengths in 35mm terms. It's the international standard for comparing lens focal lengths.

However, you do have to think about what the author means. If the intended field of view ever comes into question, then you need to convert to your 4/3 format. For example, if someone is asking you to take a photo with a "normal" lens (meaning, "same field of view as the human eye"), then you need something which has a field of view equivalent to a 50mm lens (in 35mm terms).

[allypuk]

Thank you very much dcclark, I was guessing in the right direction but its great to have it all cleared up in my head