[Planar_head]

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Right you are, I am referring to the 35mm film-camera equivalent of 50mm, or whatever the "standard" focal length is on any particular DSLR.
 
But the principle is the same, some things never change 

 
 
Ah.
 
Yeah, fast glass has always been expensive. 

And to dfkt, I do apologize for dragging the topic out again. I know you don't like the idea of turning this into a chatfest without pictures.
 
So here's my submission for today... I was experimenting with high ISO grain... don't think it worked very well.
 

 

[beerguy0]

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Quote:

A 50mm lens, perspective-wise, mimics the field of view, or perspective, of the human eye. A 35mm lens pushes the image further out by 30%, while maintaining a relatively "flat field", which keeps lens distortion minimal. Any wider and the perspective starts to curve and distort, which is not necessarily a bad thing, depending what you want to emphasize. A 100mmm lens will bring the image twice as close as a 50mm, while compressing the perspective.

 
Not on a crop sensor. The focal length of a lens is measured based on the classic 35mm equivalent focal length, but most of the cameras today have sensors smaller than a frame of 35mm film. This means that only a fraction of the 35mm frame is being seen by a crop sensor DSLR. It is as if you had a picture from a film camera (35mm frame) and then cropped it by cutting out portions of the image, effectively zooming in on a part of the image, in the case of the crop sensor, the center of the frame. Sort of like "digital zoom" except without the quality issues.
 
So, if someone wants to shoot 50mm focal length like back in the day, it's best to set the focal length based on the crop of the sensor, which varies from sensor to sensor. For example, the Pentax K7 has a 1.5x crop, which means you take the 35mm focal length (what's usually given) and multiply it by 1.5. So, in order to get exactly 50mm on a K7, it takes...
 
50mm(crop)/1.5=33.3(35mm equivalent)
 
So something like a 32mm 35mm equivalent focal length will net you 50mm on a crop sensor. The typical 18-55mm kit zoom covers this range so if you need to see it for yourself, set your kit zoom for 32mm and then 50mm and check the results.
 

My point precisely. On a 1.6x sensor, which Canon is, a 30mm lens is 48mm, and fills the role of the traditional 50mm on a FF body, which always makes me wonder why everyone buys a 50mm lens for their crop body. If you're happy with an 85mm on a FF body, then by all means, buy a 50 and enjoy it, but if you actually want a lens that will give you the same look as a the traditional 50mm, then buy a 28 or 30mm lens. Granted, the "nifty fifty" is about as cheap as it gets, lens wise, but is less useful, IMO. I have the Canon 28/1.8 and 85/1.8, and eventually will get a fast 50mm, probably the Sigma 50/1.4. I've used the Canon 50/1.4, and don't like it wide open. Also, the focusing is an older design and prone to failure.
 
Edit: One point of clarification: Focal length is a property of a lens, and is independent of format. A 90mm lens is a short telephoto on 35mm, but on a 4x5 it's a wide angle. If you look at a P&S camera, you'll see focal lengths like 6mm to 24mm, which on a tiny sensor might be 28-112mm equivalent. (Just making numbers up as an example). We equate FOV based on 35mm, because it's been the standard for so many years and it makes a handy baseline to compare to, but as time goes on it will probably become a less relevant comparison.
 
Obligatory image to stay on-topic:
 

 

 

[devwild]

Quote:

Why 50mm? People keep buying this lens for crop bodies, and I just don't get it. It's like buying an 85mm prime for a FF digital or film camera. If you want a 50mm equivalent for crop, look at the Canon 28/1.8 or Sigma 30/1.4.
 

Bypassing all the conversation - the simple answer to the question is 1) because the 50mm lenses are more prolific and cheaper (for example, most people get/recommend the 50mm 1.8 - it's $100, a no-brainer to start with), and 2) the effective length (80mm on Canon EOS) is still a very useful fixed length - good for close portraits and detail shots, as well as just being good for practicing composition and creativity as with pretty much any fixed lens.

 

[vpivinylspinner]

I do not think I have ever posted anything in here.


 


These are a few of my favorite from the weekend before last at Lime Rock Park race track.


 
While I brought lots of very heavy gear, I ended up using my lightest body, Canon 50d and zoom, 70-200 f4L for these as you could get so close to the track but had to do so much walking that the big stuff was overkill on several levels.




 





 





 

 

[gore.rubicon]

Trying my hand at this SLR stuff, I reckon I should pick up a film/slide/negative scanner, rather than using a desktop all-in-one printer scanner?
 
Canon EF, 35-105mm Macro FD, ISO200

 

[grokit]

The Canon EF is one of the best 35mm SLRs of all time, good job!

 

[BigSurSpoon]

Nice, I like the first one best.  A thought though, if you could get the front of the cars in focus, it might make them stand out a little more from the background.
 
Here's a pano from Arches National Park, UT
Canon 5d mk ii w/ 24-105 f/4
 
 

 

[Baines93]

Lovely pictures people... That panorama is stunning! Well done 

 
Yeah, I think the kit lens, and a 50mm prime will start me off well, with a 18 or 25mm soon after, and a something-200, and something-300 in the future (or just a very fast good 300?).
 
What lens do you guys think would be good for taking pictures of people at the wedding? Low light, and direct bright sunlight... I think I will need some zoom, as I don't want to be intimidating anyone to get the nice close shots of people chatting, laughing etc. at the reception... Kit lens? A bigger (than nifty fifty) prime for the best results? (bearing in mind the crop factor, around 85mm?)
 
Bearing in mind the 550d now, seems a great improvement over the 500d, but I could keep going up forever. On the other hand though, it may keep me from upgrading for a few years, whereas a D40/Pentax K-x sure wouldn't have done! Ahhh, price increase is no biggie, just the thought of a £650 camera! Need to find the equilibrium between good glass and good body I think... No point in going with a cheap body and super glass, or a super body and cheap glass... But my glass could be improved more easily I guess in the future, and it'd be easier to justify more expensive lenses if I already have a very good body.
 
Thanks alot for the help folks.
 
Sorry dfkt. You'll have plenty of pictures from me soon though... I do miss the Gear-Fi forum! Members lounge will have my thread on the third page in milliseconds 

 
Matt

 

[Planar_head]

 
Quote:

Sorry dfkt. You'll have plenty of pictures from me soon though... I do miss the Gear-Fi forum! Members lounge will have my thread on the third page in milliseconds 

 
Matt

You mean this? http://www.head-fi.org/forum/list/90
 
And my photo for today...
http://i41.tinypic.com/2eoy6n6.jpg (56k warning)

 

[Baines93]

Oh I couldn't find it when I last looked 

 
Thank you!
 
Keep an eye over there please folks, I will ask my questions in a thread over there from now on.

 

[kjpmkjp]

 

[Zodduska]

 

[danne]

Here is a picture from yesterday while out walking.
 

 

[beerguy0]

^^
 
Nice shot, good use of foreground and a perfect reflection. There is some haloing around the trees, maybe a bit too much sharpening?

 

[danne]

Quote:

^^
 
Nice shot, good use of foreground and a perfect reflection. There is some haloing around the trees, maybe a bit too much sharpening?

Yeah did some extra sharpening after the camera raw editing, might have gotten abit over my head there