Newbie questions about T2i/T3i and focal length on lenses for film/video

[gibbo]

Hey guys,

I'm trying to learn more about focal lengths and such and I have a few newbie questions to ask that I hope you guys can help with.

First of all, why do so many people clamour to get a 35mm lense onto their cameras? They go to the ends of the earth to get 35mm adaptors for their handycams and what not. I originally thought that it was because a 35mm is what actual film is. But, then I thought that film size and lens length are different, a 35mm lens on a camera with 16mm film would have the same viewing 'angle' as one on a camera with other film types and even digital. Now, all I've succeeded in doing is confusing myself. Can someone help to clear with up for me? Is a 35mm lens optimal for some reason?

If so, one would think that the best lens to get for the t2i/t3i would be a 35mm like the Canon f2, for the budget conscience? But, I read that because of the sensor size you need to multiply the lenses by 1.6 to get the real focal length when used with a t3i or t2i, which actually makes the 35mm a 56mm. And this also actually makes the popular Nifty fifty (50mm f1.8 II) a 80mm lens. Is this true? If it is, in order to get a true 35mm focal length you would need to get a 21.875mm, or 22mm lens (35/1.6=21.875), or to make it as close as possible a 22mm lens. Is that right?

Following up from that query:

If take a zoom lens that covers the 22mm length, say like the kit lens 18 - 55mm and make a little mark on the lens with a white pen or something where the 22mm focal length would be, would this be equivalent to true 35mm lens? Likewise for other focal lengths:

Say I want to shoot at 25mm (for whatever reason), if I take the same kit lens (18 - 55mm) and find exactly where 25mm is, would I get the same view as from a fixed 25mm prime lens worth many thousands of dollars (don't even know if prime 25mm exist, I'm just speculating for arguments sake, and I know the quality would be very different but I'm talking about only the viewing angle of the lens here)

Thanks for helping me clear this up.

 

[gpforet]

Your calculations are correct. Here's some of the reasoning behind the lens choices.

22mm lens with the 1.6 crop gives you about 35mm. This is considered a middle wide angle lens.
35mm with 1.6 crop gives you about 56mm. 50mm is considered to be the same width as we see with our eyes.
50mm with 1.6 crop gives you about 80mm. 70-80mm is considered the optimal portrait lens, great for closeups.

The general issue regarding 35mm lens adapters is that this adapter gives access to the massive amounts of camera lens out there. Typically this gives you better optics, and more importantly, manual control of the iris, allowing complete control over depth of field. The downside to using a 35mm adapter on a video camera is that you'll lose an F-stop or two with the adapter. Add that to the weak low light capabilities of most video cameras and you'll now need far more lighting than without the adapter.

The solution for many filmmakers is to migrate to DSLRs. Low light capabilities of DSLRs blow video cameras away. Also, since there's no adapter, you don't lose that F-stop or two.

Hey guys,

I'm trying to learn more about focal lengths and such and I have a few newbie questions to ask that I hope you guys can help with.

First of all, why do so many people clamour to get a 35mm lense onto their cameras? They go to the ends of the earth to get 35mm adaptors for their handycams and what not. I originally thought that it was because a 35mm is what actual film is. But, then I thought that film size and lens length are different, a 35mm lens on a camera with 16mm film would have the same viewing 'angle' as one on a camera with other film types and even digital. Now, all I've succeeded in doing is confusing myself. Can someone help to clear with up for me? Is a 35mm lens optimal for some reason?

If so, one would think that the best lens to get for the t2i/t3i would be a 35mm like the Canon f2, for the budget conscience? But, I read that because of the sensor size you need to multiply the lenses by 1.6 to get the real focal length when used with a t3i or t2i, which actually makes the 35mm a 56mm. And this also actually makes the popular Nifty fifty (50mm f1.8 II) a 80mm lens. Is this true? If it is, in order to get a true 35mm focal length you would need to get a 21.875mm, or 22mm lens (35/1.6=21.875), or to make it as close as possible a 22mm lens. Is that right?

Following up from that query:

If take a zoom lens that covers the 22mm length, say like the kit lens 18 - 55mm and make a little mark on the lens with a white pen or something where the 22mm focal length would be, would this be equivalent to true 35mm lens? Likewise for other focal lengths:

Say I want to shoot at 25mm (for whatever reason), if I take the same kit lens (18 - 55mm) and find exactly where 25mm is, would I get the same view as from a fixed 25mm prime lens worth many thousands of dollars (don't even know if prime 25mm exist, I'm just speculating for arguments sake, and I know the quality would be very different but I'm talking about only the viewing angle of the lens here)

Thanks for helping me clear this up.

 

[SinEater]

You're confusing different things Gibbo. 35mm adaptors allow video cameras to use lenses designed for 35mm film cameras. These lenses can come in any focal length, including 35mm. Without an adaptor those video cameras are stuck with their built in fixed lens. DSLRs are already designed to use interchangeable lenses and therefore don't need an adaptor.

 

[gibbo]

Thanks for the replies guys.

Your calculations are correct. Here's some of the reasoning behind the lens choices.

22mm lens with the 1.6 crop gives you about 35mm. This is considered a middle wide angle lens.
35mm with 1.6 crop gives you about 56mm. 50mm is considered to be the same width as we see with our eyes.

Would it be safe to say that if I could only use one lens to make short films with I should go with something that's closest to what we see? Wouldn't that be more natural? (EDIT: hang on, I could just get a 50mm lense and stand a bit further back than I would with a 30 or 35mm lens to get the same viewing angle, right? So the actual focal length of the lens doesn't really matter too much, it's more about where I stand?)

I could get a 30mm lens which would be 48mm on a t2i or a 35mm lens that would be 56mm on a t2i.

50mm with 1.6 crop gives you about 80mm. 70-80mm is considered the optimal portrait lens, great for closeups.

Why is that? is it because it you don't need to get too close to the subject to get a good shot, and because it's not a wide lens there's none of that warping of the picture you get with wide angle lenses? I would imagine that length (a 50mm lens) is JUST over the line where that fish eye-ing/warping stops.

The general issue regarding 35mm lens adapters is that this adapter gives access to the massive amounts of camera lens out there. Typically this gives you better optics, and more importantly, manual control of the iris, allowing complete control over depth of field. The downside to using a 35mm adapter on a video camera is that you'll lose an F-stop or two with the adapter. Add that to the weak low light capabilities of most video cameras and you'll now need far more lighting than without the adapter.

The solution for many filmmakers is to migrate to DSLRs. Low light capabilities of DSLRs blow video cameras away. Also, since there's no adapter, you don't lose that F-stop or two.

Interesting... thanks heaps for your help!

You're confusing different things Gibbo. 35mm adaptors allow video cameras to use lenses designed for 35mm film cameras. These lenses can come in any focal length, including 35mm. Without an adaptor those video cameras are stuck with their built in fixed lens. DSLRs are already designed to use interchangeable lenses and therefore don't need an adaptor.

Ohhhhhhh... right... I was getting confused as I though a 35mm adapter was an adapter to use a 35mm lense. D'oh!

So, why 35mm camera lenses? Why not 16mm camera lenses or lenses from other cameras? Is it because 35mm, being the most popular, there are more lenses more readily available making them easier to get?

 

[SinEater]

So, why 35mm camera lenses? Why not 16mm camera lenses or lenses from other cameras? Is it because 35mm, being the most popular, there are more lenses more readily available making them easier to get?

16mm camera lenses wouldn't cover the sensor size of a DSLR, which is larger than 16mm film. 35mm lenses are large enough to cover the sensor.

 

[Cracker Funk]

What SinEater said.

Also, you don't need to worry about the crop-factor. It also confused the crap out of me, when I switched to DSLR (I came from a DV background).

The crop-factor really only matters to people who come from a 35mm photography background. Serious photographers have an image in their mind, when they discuss lens focal lengths. So, when these serious photographers switched from 35mm film still cameras to DSLR, they had to do mental-math to figure out what an image would look like, because of the crop-factor. People like you and me, however, coming from a DV background (or maybe you're just starting), we have no pre-existing image in our heads of what a particular focal-length "should" look like.

For you and me, on a T2i, or any other crop-factor, an 18mm will look like an 18mm, because that's all we know! A 50mm will look like a 50mm!

Phew! Confusion ended. I promise, there is absolutely no reason for you to worry about this. It's good for you to know that the issue exists, but that's really only because you might someday be working with someone with a photography background, and they need to do all this mental-math in their heads.

 

[gibbo]

Thanks guys for helping me clear up a few things!

16mm camera lenses wouldn't cover the sensor size of a DSLR, which is larger than 16mm film. 35mm lenses are large enough to cover the sensor.

Got it, thanks...

What SinEater said.

Also, you don't need to worry about the crop-factor. It also confused the crap out of me, when I switched to DSLR (I came from a DV background).

The crop-factor really only matters to people who come from a 35mm photography background. Serious photographers have an image in their mind, when they discuss lens focal lengths. So, when these serious photographers switched from 35mm film still cameras to DSLR, they had to do mental-math to figure out what an image would look like, because of the crop-factor. People like you and me, however, coming from a DV background (or maybe you're just starting), we have no pre-existing image in our heads of what a particular focal-length "should" look like.

For you and me, on a T2i, or any other crop-factor, an 18mm will look like an 18mm, because that's all we know! A 50mm will look like a 50mm!

Phew! Confusion ended. I promise, there is absolutely no reason for you to worry about this. It's good for you to know that the issue exists, but that's really only because you might someday be working with someone with a photography background, and they need to do all this mental-math in their heads.

Phew, thanks for that. Certainly cleared up a lot for me!

Just one questions remains plaguing me though, and forget about the crop factor part of it:

If take a zoom lens that covers the 22mm length, say like the kit lens 18 - 55mm and make a little mark on the lens with a white pen or something where the 22mm focal length would be, would this be equivalent to true 35mm lens? Likewise for other focal lengths:

Say I want to shoot at 25mm (for whatever reason), if I take the same kit lens (18 - 55mm) and find exactly where 25mm is, would I get the same view as from a fixed 25mm prime lens worth many thousands of dollars (don't even know if prime 25mm exist, I'm just speculating for arguments sake, and I know the quality would be very different but I'm talking about only the viewing angle of the lens here)

Thanks for helping me clear this up.

 

[chilipie]

Just one questions remains plaguing me though, and forget about the crop factor part of it:

The short answer is yes. The slightly longer answer is that you can, but unless you're using a proper cine or broadcast lens, the markings are not going to be completely accurate. If all you want to do is have roughly a 25mm lens then it doesn't matter, but if you need (for example) to match shots for VFX work, that difference can be crucial.

 

[gibbo]

The short answer is yes. The slightly longer answer is that you can, but unless you're using a proper cine or broadcast lens, the markings are not going to be completely accurate. If all you want to do is have roughly a 25mm lens then it doesn't matter, but if you need (for example) to match shots for VFX work, that difference can be crucial.

Thanks. With me it will be anything but accurately matching shots! As long as it's roughly the same then that's good.

Does this mean then, in your opinion, that it would be a good idea to invest in a good fast zoom lens that covers, say, 10mm - 60mm so you can have all the lengths in between too in one lens rather than carting around extra prime lenses?

Well, at least, for someone like me anyway, who is just wanting an all rounder type of lens.

 

[PaulGriffith]

A fast zoom lens still isn't as fast as primes are. When recommending lenses, big question is:

Are you doing run and gun or a narrative style shoot?

Run and Gun, ie: Live events, no set up time, etc.. A fast zoom is great. No time spent swapping lenses.

Narrative style shoot where you spend time tweaking lights and have the opportunity for multiple takes, primes are better. Primes take longer to swap focal lengths, but in the same price ranges primes are way faster and generally better build quality than an equally priced zoom.

You won't find a 10-60mm zoom though. Tokina has an 11-16 if you need really wide, then there's a 17-50mm 2.8 and then 24-70mm 2.8s. Many brands offer those two focal lengths, or something close to it.

 

[Gonzo_Entertainment]

I agree that zooms are for event shooters and documentarians. Trying to capture something in real time when there is not time for swapping lenses. For narrative film making primes are the way to go for a lot of reasons.

 

[gibbo]

Thanks for the replies guys, I want to wait until I actually got the camera before I continued with this thread. I just bought a 600D/T3i body not one week ago and I also purchased the 50mm f1.8 prime (nifty fifty) with it (no kit lenses).

No idea what I'm doing! Still trying to get used to it, I know the basics it's just a matter of practicing so I know which settings to use in a given situation rather than what I do now which is more like play around with them for a few minutes before I take the photo.

I was wondering how the settings and skills of still photography translate to film/cinematography? For example: Shot composition (rule of thirds, leading lines etc) and all the settings like the fstop, shutter speed etc? I'm hoping I can get good at taking still photos and just transfer those skills over to cinematography :S

A fast zoom lens still isn't as fast as primes are. When recommending lenses, big question is:

Are you doing run and gun or a narrative style shoot?

Run and Gun, ie: Live events, no set up time, etc.. A fast zoom is great. No time spent swapping lenses.

Narrative style shoot where you spend time tweaking lights and have the opportunity for multiple takes, primes are better. Primes take longer to swap focal lengths, but in the same price ranges primes are way faster and generally better build quality than an equally priced zoom.

You won't find a 10-60mm zoom though. Tokina has an 11-16 if you need really wide, then there's a 17-50mm 2.8 and then 24-70mm 2.8s. Many brands offer those two focal lengths, or something close to it.

Hmm... well, I'm still learning and completely new so I have no idea what I'll be doing. I'm just trying to get better at using the camera in general and get used to the settings. But, if I had to say what I will be doing in the not too distant future, on top of general still photography it would be the run and gun/guerilla filmmaking style first and foremost, situations like filming a scene on the sly when you're not really supposed to and sneaking into work after hours and using the office and toilets for a short etc.

So I guess decent zooms would be appropriate for that?

I agree that zooms are for event shooters and documentarians. Trying to capture something in real time when there is not time for swapping lenses. For narrative film making primes are the way to go for a lot of reasons.

yep, that makes perfect sense. Narrative is definitely the big goal (feature length film) but I'm hoping by the time I'm ready for that I will either have a proper cinematographer and hire propper equipment or at least be able to borrow it myself from someone.

 

[escher]

Might as well toss my 2 cents in here:

• You can get some amazing high-quality 35mm camera glass that blows the doors off of standard camcorder lenses. Better contrast and and color fidelity. You don't get nearly as much of that "video" look.
• Of course, these lenses cost a lot.
• My 85mm f1.2 lens cost over $2000.
• And it was worth every penny. By far the sharpest lens I have ever used.
• Crop factor cameras will have a different depth of field compared to the equivalent focal length on small and bigger sensors. For example, a 35mm lens on a 1.6 crop factor sensor will closely match the field of view of a 50mm on a full-frame sensor, but the DOF will be shallower on the full-frame camera. Some people prefer this look -- I love my 50mm f1.4 on my full-frame whereas a 35mm on a crop factor camera merely looks "okay".
• As mentioned in earlier posts, cinema-quality 35mm lenses have maually-adjustable apertures (irises) that are smooth (as opposed to only moving in 1/3rd or 1/2-stop increments). This is less of a big deal unless you need to alter your lights and aperture in tandem to keep the same exposure brightness but have your DOF change in real-time. This would look really cool but is beyond the abilities of most indie filmmakers.
• 35mm camera lenses are a better investment because when you upgrade to a better camera body you can re-use them instead of having to buy all new lenses. Camera bodies come and go but lenses are an investment.

For shooting video, you're going to want prime lenses (lenses that do not zoom in and out). Primes are sharper, have better contrast/color, and exhibit far less distortion around the edges of the frame (most noticeable at wider focal lengths). They also tend to let in a lot more light.

Manual focus is also important and this is an area where most DSLR lenses fall flat. The best manual focus rings I've found have been on Zeiss lenses (of which I only own an 18mm at the moment). The worst is, oddly enough, on my otherwise wonderful 85mm.

If you buy a 50mm lens, get the Canon 50mm f1.4. It is leaps and bounds better than the "nifty 50" 50mm f1.8, and even rivals the quality of the much more expensive L-series lenses. It will make an excellent "medium close-up" lens on your crop-factor body. The 35mm f2.0 makes for a decent normal-FOV lens. I don't know of any low-cost 18mm primes, but the 18-55 kit lens isn't actually too bad.

If you ever find yourself using a full-frame camera, the same basic three-lens setup that matches the above would be 24mm for wide angle, 50mm for normal, and 85mm for medium close-up.

Edit:

Here are two examples of why you should use primes. These are before/after noise-reduction-test video stills, and the only light in the scene is from candles. You'd have a hell of a time getting these kind of shots from a camcorder, or even on a DSLR using a zoomable lens due to the amount of light lost. The extra light helps me keep the ISO at a sane setting, making the noise-removal pass much easier.

• 85mm f1.2 (similar to a 50mm for 1.6x crop)
• 50mm f1.4 (similar to 35mm for 1.6x crop)

(The color's a bit flat because I'm using the Technicolor CineStyle color profile to get the most latitude I can to make color-correction easier when I get to that step.)

 

[Psychosis Media]

if you looking at lenses do not forget the vintage lenses out there...they are only a quarter of the price of current modern lenses and they have better built quality...the optics on some of the vintage lenses cant be beat.

I just picked up a 28mm Focal mc (a old kmart brand ..all metal casing and really sharp pics) for $14 with shipping and a Rikenon 28mm for about $18 with shipping. The Rikenon has a really good rep ..i tested it and its awsome!

A few months ago i picked up a 58mm Helios for about $23 with shipping..this is a legendary lens...really good glass
and a Asahi Takumat 55mm for about $27..these lenses are skyrocketing in price!!! most now are going for $40-$70 or more sometimes....real quality lens.

All these 25-40year old lenses are metal construction and heavy..so they feel good. I really hate the modern plastic lenses out there..they feel cheap and overpriced..do your reseach before you dive into vintage...there are several standards and also each brand name has good and bad productions!
and

 

[gibbo]

Thanks guys again for the relpies, you've all been a really big help. I've been playing around with my camera in differen situations before I come back and post, hoping to get a better handle on things. Something I've noticed, input would be appreciated:

I borrowed my friends Kit Lens (18-55mm f3.5 - 5.6) and indoors it's useless, maybe I'm doing something wrong but even with all the lights on it is horrible. Interestingly though, even @ 1.8 my 50mm prime sux indoors too, but outside in low light (like at dusk or even at night) it performs surprisingly well. EG: Inside my living room with all the lights on, 50mm 1.8 @1600 ISO 30 shutter speed is not great, but outside sitting in my car at the traffic lights filming cars infront of me is MUCH better, even quite impressive, but there's much more light indoors.

I've also seen videos on youtube of just lighting with one candle only which is no where near as bright as my living room lights! EG, even thought it's f1.4, this video is shot at ISO 100!
http://www.youtube.com/watch?v=NVwxLR6pAFM

Might as well toss my 2 cents in here:

• You can get some amazing high-quality 35mm camera glass that blows the doors off of standard camcorder lenses. Better contrast and and color fidelity. You don't get nearly as much of that "video" look.
• Of course, these lenses cost a lot.
• My 85mm f1.2 lens cost over $2000.
• And it was worth every penny. By far the sharpest lens I have ever used.
• Crop factor cameras will have a different depth of field compared to the equivalent focal length on small and bigger sensors. For example, a 35mm lens on a 1.6 crop factor sensor will closely match the field of view of a 50mm on a full-frame sensor, but the DOF will be shallower on the full-frame camera. Some people prefer this look -- I love my 50mm f1.4 on my full-frame whereas a 35mm on a crop factor camera merely looks "okay".
• As mentioned in earlier posts, cinema-quality 35mm lenses have maually-adjustable apertures (irises) that are smooth (as opposed to only moving in 1/3rd or 1/2-stop increments). This is less of a big deal unless you need to alter your lights and aperture in tandem to keep the same exposure brightness but have your DOF change in real-time. This would look really cool but is beyond the abilities of most indie filmmakers.
• 35mm camera lenses are a better investment because when you upgrade to a better camera body you can re-use them instead of having to buy all new lenses. Camera bodies come and go but lenses are an investment.

For shooting video, you're going to want prime lenses (lenses that do not zoom in and out). Primes are sharper, have better contrast/color, and exhibit far less distortion around the edges of the frame (most noticeable at wider focal lengths). They also tend to let in a lot more light.

Manual focus is also important and this is an area where most DSLR lenses fall flat. The best manual focus rings I've found have been on Zeiss lenses (of which I only own an 18mm at the moment). The worst is, oddly enough, on my otherwise wonderful 85mm.

If you buy a 50mm lens, get the Canon 50mm f1.4. It is leaps and bounds better than the "nifty 50" 50mm f1.8, and even rivals the quality of the much more expensive L-series lenses. It will make an excellent "medium close-up" lens on your crop-factor body. The 35mm f2.0 makes for a decent normal-FOV lens. I don't know of any low-cost 18mm primes, but the 18-55 kit lens isn't actually too bad.

If you ever find yourself using a full-frame camera, the same basic three-lens setup that matches the above would be 24mm for wide angle, 50mm for normal, and 85mm for medium close-up.

Edit:

Here are two examples of why you should use primes. These are before/after noise-reduction-test video stills, and the only light in the scene is from candles. You'd have a hell of a time getting these kind of shots from a camcorder, or even on a DSLR using a zoomable lens due to the amount of light lost. The extra light helps me keep the ISO at a sane setting, making the noise-removal pass much easier.

• 85mm f1.2 (similar to a 50mm for 1.6x crop)
• 50mm f1.4 (similar to 35mm for 1.6x crop)

(The color's a bit flat because I'm using the Technicolor CineStyle color profile to get the most latitude I can to make color-correction easier when I get to that step.)

Wow thanks for that post!

I actually really wanted to ask what the recommended lenses were for general, all round filmmaking. 24ish, 50mm and 85mm. Thanks great! I've got my 50mm which is equivalent to an 80mm, which is good enough, although I find this focal length and minimum zoom distance to be really awkward and wonder what kind of shots/situations to use it in?

The Canon 35mm f2 that you recommended: Would that loss of .2 fstop make a huge difference in low light? I want all I can get. Or should I just go straight for the decently priced Sigma 30mm f1.4? here: http://www.bhphotovideo.com/c/product/381615-REG/Sigma_300101_30mm_f_1_4_EX_DC.html

Or maybe there's another option out there?

if you looking at lenses do not forget the vintage lenses out there...they are only a quarter of the price of current modern lenses and they have better built quality...the optics on some of the vintage lenses cant be beat.

I just picked up a 28mm Focal mc (a old kmart brand ..all metal casing and really sharp pics) for $14 with shipping and a Rikenon 28mm for about $18 with shipping. The Rikenon has a really good rep ..i tested it and its awsome!

A few months ago i picked up a 58mm Helios for about $23 with shipping..this is a legendary lens...really good glass
and a Asahi Takumat 55mm for about $27..these lenses are skyrocketing in price!!! most now are going for $40-$70 or more sometimes....real quality lens.

All these 25-40year old lenses are metal construction and heavy..so they feel good. I really hate the modern plastic lenses out there..they feel cheap and overpriced..do your reseach before you dive into vintage...there are several standards and also each brand name has good and bad productions!
and

I asked some of my photography friends about Vintage lenses, they have Nikon cameras and said that all, or at least most modern Nikon cameras can fit their vitange lenses but Canons might need mounts. I did some research on this and it appears to be the case. If i'm not wrong I would need a different mount for each lens, unless it's an actual canon vintage lens? Even then I would lose a few stops of light using the mounts?


Now the ultimate question:

If you guys had to choose one lens, just one, to shoot short films on, which focal length would it be? Just a general all round Prime/fixed lens. I was sure I wanted around a 20mm (30 - 25mm on my camera), which i thought we be OK for pretty much everything, but now I'm not so sure.

Thanks very much guys and Merry Christmas!

 

[escher]

I borrowed my friends Kit Lens (18-55mm f3.5 - 5.6) and indoors it's useless, maybe I'm doing something wrong but even with all the lights on it is horrible.

f3.5 and up are really tricky to use in standart indoor lighting due to the low luminosity. You'll need to shoot at ISO 2500+ to get proper exposure and you'll start seeing a lot of grain at that point. f2.8 and lower should work much better, with f2.0 and f1.4 working out very well.

I actually really wanted to ask what the recommended lenses were for general, all round filmmaking. 24ish, 50mm and 85mm. Thanks great! I've got my 50mm which is equivalent to an 80mm, which is good enough, although I find this focal length and minimum zoom distance to be really awkward and wonder what kind of shots/situations to use it in?

The 50/80 lenses (crop/full) are good for medium closeups. You'll get a decent DOF and flattering angles that work well for headshots.

The Canon 35mm f2 that you recommended: Would that loss of .2 fstop make a huge difference in low light? I want all I can get.

f2 works pretty well indoors, although you always want to use the brightest lights you can get your hands on. Yes, f1.4 will let in more light, but the tradeoff is the DOF starts to get so shallow you can have trouble keeping your subject in focus. At f1.2 it can get very difficult. This is less of an issue at 35mm than it is at 50 and 80, but you should be aware of that all the same.

I've never used that Sigma so I can't really comment on it. Could you maybe rent one for a weekend to try it out?

If you guys had to choose one lens, just one, to shoot short films on, which focal length would it be? Just a general all round Prime/fixed lens. I was sure I wanted around a 20mm (30 - 25mm on my camera), which i thought we be OK for pretty much everything, but now I'm not so sure.

If you have only one lens... that's tricky. You can either pick a single focal length and change your style of cinematography to fit whatever you've picked -- 35mm would be a "normal" FOV, but a 24 or 18 might be stylistically prettier.

On the other hand (if you have the room and the light), you could shoot using a longer lens (50-80), like the movie "Ran".

Personally, if I only had a single lens to use, I would go with a versatile zoom lens and just deal with the barrel distortion at the wider lengths. The 18-135 and 18-200 look promising, although its minimum aperture of f3.5-5.6 means you'll need additional lights if you're shooting indoors.

If you can afford it, the 24-70mm f2.8 L is a beautiful lens that would give you wide-to-medium framing and works well in low light. I have this lens and it takes sharp, beautiful images. The downsides: it's a very heavy lens, and it does not have any image stabilization. The 24-105 f4 L has IS, but again won't do as well in low light.

 

[gibbo]

Thanks for the reply!

Thanks so much for helping me to understand all this! There's so much to learn and I'm currently looking for some cinematography books to buy.

Correct me if I'm wrong but it seems to look a touch more "cinematic" when you position the camera a bit lower, halfway down the frame in relation to the subject, rather than just at the camera operators eye level. Example:

If I'm shooting a full body shot of someone walking into a door, it looks better to me positioning the camera at their waste level or higher depending on the lens.

Anyway....

f3.5 and up are really tricky to use in standart indoor lighting due to the low luminosity. You'll need to shoot at ISO 2500+ to get proper exposure and you'll start seeing a lot of grain at that point. f2.8 and lower should work much better, with f2.0 and f1.4 working out very well.

The 50/80 lenses (crop/full) are good for medium closeups. You'll get a decent DOF and flattering angles that work well for headshots.

Right, got it. So something like this:

A 24mm-ish equiv. (around 15mm on my 600D) for wide shots like an establishing shot of two people standing in a forrest or field and other full body or 3/4 body length shots

A 50mm equiv. (around 30mm on my 600D) for all "normal" shots like POV shots, half body shots, tracking shots etc.

An 85mm equiv. (My 50mm) for medium shots and headshots such as dialogue scenes etc

f2 works pretty well indoors, although you always want to use the brightest lights you can get your hands on. Yes, f1.4 will let in more light, but the tradeoff is the DOF starts to get so shallow you can have trouble keeping your subject in focus. At f1.2 it can get very difficult. This is less of an issue at 35mm than it is at 50 and 80, but you should be aware of that all the same.

Didn't realise that about the DOF, it makes sense though. I guess that is an upside to not buying pricey f1.2 lenses!

What I was getting at was something like this:

The difference between f2 and f1.8 wouldn't be much, because 1.8 isn't a whole new stop. But, the difference between f2 and f1.4 would be because that's a whole new stop. So, f1.4 would let in twice as much light as f2, right?

I've never used that Sigma so I can't really comment on it. Could you maybe rent one for a weekend to try it out?

Not sure about that... I'll have to look into it.

If you have only one lens... that's tricky. You can either pick a single focal length and change your style of cinematography to fit whatever you've picked -- 35mm would be a "normal" FOV, but a 24 or 18 might be stylistically prettier.

When you say a 35mm would be "normal", do you mean 35mm on my crop sensor? Or do you mean 35mm on a full frame (35mm camera equivalent)? I thought 50mm was "normal"?

On the other hand (if you have the room and the light), you could shoot using a longer lens (50-80), like the movie "Ran".

Was this film shot at longer focal lengths? I haven't seen it yet, I think he did the same for Yojimbo? I recall somewhere saying that he used telephoto lenses.

Personally, if I only had a single lens to use, I would go with a versatile zoom lens and just deal with the barrel distortion at the wider lengths. The 18-135 and 18-200 look promising, although its minimum aperture of f3.5-5.6 means you'll need additional lights if you're shooting indoors.

If you can afford it, the 24-70mm f2.8 L is a beautiful lens that would give you wide-to-medium framing and works well in low light. I have this lens and it takes sharp, beautiful images. The downsides: it's a very heavy lens, and it does not have any image stabilization. The 24-105 f4 L has IS, but again won't do as well in low light.

eek, how much was that lense if you don't mind me asking?