Lens question for you Canon 20D owners

[Doggiedog]

I'm itching to get back into photography with the 20D. I have a Canon T-90 and a Contax RTS2 but haven't used film in a long time.

When getting a lens for the 20D, what is the adjustment you have to make to get the correct size? A 50mm lens is not 50mm on a digicam right? What would be most versatile and appropriate lens to get with this camera? I'd like something fast but not outrageously expensive and if you know a good place to buy it besides B&H let me know.

Thanks.

 

[sohcrates]

this helps explain the 1.6x crop factor

http://forums.dpreview.com/for...1&message=11303192

due to size of sensor compared to 35 mm film

 

[Doggiedog]

Originally posted by: sohcrates
this helps explain the 1.6x crop factor

http://forums.dpreview.com/for...1&message=11303192

due to size of sensor compared to 35 mm film

So I take it that picture on the right is using a 35mm lens also?

 

[kami333]

Originally posted by: Doggiedog

Originally posted by: sohcrates
this helps explain the 1.6x crop factor

http://forums.dpreview.com/for...1&message=11303192

due to size of sensor compared to 35 mm film

So I take it that picture on the right is using a 35mm lens also?

All the same lens, it is showing what the 1.6x crop factor does when you print it out at full page, basically works like a 1.6x zoom.

 

[sohcrates]

Originally posted by: Doggiedog

Originally posted by: sohcrates
this helps explain the 1.6x crop factor

http://forums.dpreview.com/for...1&message=11303192

due to size of sensor compared to 35 mm film

So I take it that picture on the right is using a 35mm lens also?

no. left pic is 35mm. middle pic is what 1.6x captures

right picture is digicam print printed at same size as 35mm capture

effectively, you cannot capture as much of the scene at the same focal length as you can with 35 mm...BUT, because of the high resolution of digicams these days, you can get the same size output as far as printing quality

 

[Staples]

Well, I learned something new today. No wonder 30mm doesn't seem as wide on my digital camera. Can't help you on the lense though, I have a point and shoot digital camera.

 

[Wallydraigle]

Even on a 1.6x sensor it's hard to beat a 50mm lens. They're light, cheap, and fast, and even the cheapest ones take great pictures. You can get a 50mm f/1.8 for ~$70, new. You'll just have to back up a little more than you would with a full frame camera.

 

[Anubis]

the crop factor thing is confusing nd is still debated to death, read at DP review in either the nikon or canon forums, many many many threads, i own both a 50mm and 35mm prime lenses, w/ nikons 1.5x crop factor they become ~75mm and ~55mm

no you may think Oh ill just get a 35mm lens and itll be like a 50mm lens on film, well thats only 1/2 correct, while the effective FOV of the 35mm is about that of a 50mm lens the pictures still look like they were taken with a 35mm lens, they are pretty damn wide, even with the crop the wide aspect ration of a 35mm lens stays, the 50mm lens has a effective FOV of 75mm but still produces pictures that look like a 50mm lens not a 75mm lens,

 

[Doggiedog]

The more studying I've done, the more confusing this is getting.

So these new Canon lenses now have image stabilizing which reduces the f-stop by about 3? I was looking at the specs for the Canon 17-85MM f4-5.6 and at first glance it looks pretty mediocre but this IS is supposed to reduce improve it to better than f2.8?

Hmm.

 

[Anubis]

IS does not give you 3 full stops it gives you about 2/3 of a stop to a full stop at best

 

[Doggiedog]

Originally posted by: Anubis
IS does not give you 3 full stops it gives you about 2/3 of a stop to a full stop at best

Text

Says up to 3 in the article though.

So I guess its still better to get a faster lens than a slower one with IS?

 

[Anubis]

Originally posted by: Doggiedog

Originally posted by: Anubis
IS does not give you 3 full stops it gives you about 2/3 of a stop to a full stop at best

Text

Says up to 3 in the article though.

So I guess its still better to get a faster lens than a slower one with IS?

i dont see where it says IS gves you 3 stops. and if i just missed it, it is the fiorst time ive ever heard of it giveing you more then a stop

 

[Doggiedog]

Why put Image Stabilization into a wide angle to short telephoto zoom lens? For the same reason you put it into telephoto lenses - to reduce camera shake. Since the Canon EF-S 17-85mm f/4-5.6 IS USM Lens has third generation IS, it can be handheld up to 3 f-stops lower than a non-IS lens at the same focal length.

3 f stops sounds like a lot.

 

[Anubis]

Originally posted by: Doggiedog

Why put Image Stabilization into a wide angle to short telephoto zoom lens? For the same reason you put it into telephoto lenses - to reduce camera shake. Since the Canon EF-S 17-85mm f/4-5.6 IS USM Lens has third generation IS, it can be handheld up to 3 f-stops lower than a non-IS lens at the same focal length.

3 f stops sounds like a lot.

yea it is a lot, and the reason i didnt see it is cause opera was being stupid with that page and only showing part of the article

go ask on DPreview is IS gives you 3 stops, im pretty sure that they will agree that thats kinda BS

 

[ElFenix]

Originally posted by: Doggiedog

Why put Image Stabilization into a wide angle to short telephoto zoom lens? For the same reason you put it into telephoto lenses - to reduce camera shake. Since the Canon EF-S 17-85mm f/4-5.6 IS USM Lens has third generation IS, it can be handheld up to 3 f-stops lower than a non-IS lens at the same focal length.

3 f stops sounds like a lot.

why are they talking about f-stops when they should be talking about shutter timing? you can keep the shutter open longer, which means you have to narrow the aperature a bit to get the same exposure, or you can take pics in worse light than before (which i guess is a must when f/4 is as good as it gets)

 

[DBL]

Originally posted by: Anubis
IS does not give you 3 full stops it gives you about 2/3 of a stop to a full stop at best

There are different versions of Canons IS. The newer version is supposed to give 3 stops while the older gives 2 stops. It's definitely a lot better than 2/3 of a stop though.

It really comes down to how far you want to push the envelope. I can shoot w/ my 28-135IS at 1/50 of a second and get reasonably sharp photos, especially considering the effective 216mm AOV. However, I?d prefer to keep the Tv up over 1/100 if I can help it. It just provides for some more margin of error. I hear the IS in the 18-85 is a serious upgrade over the IS in the 28-135 though.

 

[DBL]

Originally posted by: Anubis
the crop factor thing is confusing nd is still debated to death, read at DP review in either the nikon or canon forums, many many many threads, i own both a 50mm and 35mm prime lenses, w/ nikons 1.5x crop factor they become ~75mm and ~55mm

no you may think Oh ill just get a 35mm lens and itll be like a 50mm lens on film, well thats only 1/2 correct, while the effective FOV of the 35mm is about that of a 50mm lens the pictures still look like they were taken with a 35mm lens, they are pretty damn wide, even with the crop the wide aspect ration of a 35mm lens stays, the 50mm lens has a effective FOV of 75mm but still produces pictures that look like a 50mm lens not a 75mm lens,

Sorry, but unless you are taking close-up pictures w/ a wide angle lens, where distortion plays a factor, you will not see a noticeable difference between a 50mm on 35mm format and an 80mm on a 1.6x crop DSLR. The pictures will look exactly the same. How can the FOV be the same but one picture look "pretty damn wide" compared to the other? That makes no sense.

 

[Doggiedog]

Originally posted by: DBL

Originally posted by: Anubis
IS does not give you 3 full stops it gives you about 2/3 of a stop to a full stop at best

There are different versions of Canons IS. The newer version is supposed to give 3 stops while the older gives 2 stops. It's definitely a lot better than 2/3 of a stop though.

It really comes down to how far you want to push the envelope. I can shoot w/ my 28-135IS at 1/50 of a second and get reasonably sharp photos, especially considering the effective 216mm AOV. However, I?d prefer to keep the Tv up over 1/100 if I can help it. It just provides for some more margin of error. I hear the IS in the 18-85 is a serious upgrade over the IS in the 28-135 though.

Nice post.

I may have to make this the lens.

 

[element]

I have IS on my cheapo digicam, it's called a tripod...


kidding!

 

[Anubis]

Originally posted by: DBL

Originally posted by: Anubis
the crop factor thing is confusing nd is still debated to death, read at DP review in either the nikon or canon forums, many many many threads, i own both a 50mm and 35mm prime lenses, w/ nikons 1.5x crop factor they become ~75mm and ~55mm

no you may think Oh ill just get a 35mm lens and itll be like a 50mm lens on film, well thats only 1/2 correct, while the effective FOV of the 35mm is about that of a 50mm lens the pictures still look like they were taken with a 35mm lens, they are pretty damn wide, even with the crop the wide aspect ration of a 35mm lens stays, the 50mm lens has a effective FOV of 75mm but still produces pictures that look like a 50mm lens not a 75mm lens,

Sorry, but unless you are taking close-up pictures w/ a wide angle lens, where distortion plays a factor, you will not see a noticeable difference between a 50mm on 35mm format and an 80mm on a 1.6x crop DSLR. The pictures will look exactly the same. How can the FOV be the same but one picture look "pretty damn wide" compared to the other? That makes no sense.

it makes perfect sence, a 50mm lens produces a pictured like a 50mm lens regarless if its on a film body ar a digi cam with a 1.6x crop factor, so a 35mm lens will not produce pictures that look like thoes taken witha 50mm lens on a film cam, they will look like 35mm pics on a film cam

 

[DBL]

Originally posted by: Doggiedog
Nice post.

I may have to make this the lens.

I would. I'll probably get around to selling my 28-135 at some point and pick this lens up. It's got a fantastic range and is perfect for times when you can only carry 1 lens. Sure, it's got its detractors but it's mostly people who examine pictures at the pixel level and are only satisfied w/ the absolute best lenses (L series) that Canon makes. However, the truth of the matter is that the absolute sharpness and quality of a lens has only a little to do with actually producing a good photograph. There is so much more to a good photograph than the quality of the lens used to capture it.

 

[DBL]

Originally posted by: Anubis
it makes perfect sence, a 50mm lens produces a pictured like a 50mm lens regarless if its on a film body ar a digi cam with a 1.6x crop factor, so a 35mm lens will not produce pictures that look like thoes taken witha 50mm lens on a film cam, they will look like 35mm pics on a film cam

If the Angle or Field of view is equivalent, then how would the picture look different? Saying that it looks like a 35mm lens regardless doesn't mean anything. The crop factor reduces the Angle of view. The resulting picture looks as if it was taken by a lens with a focal length 1.6x greater.